Gathering spectra from multiple optical heads

A polishing apparatus includes a platen to hold a polishing pad having a plurality of optical apertures, a carrier head to hold a substrate against the polishing pad, a motor to generate relative motion between the carrier head and the platen, and an optical monitoring system. The optical monitoring system includes at least one light source, a common detector, and an optical assembly configured to direct light from the at least one light source to each of a plurality of separated positions in the platen, to direct light from each position of the plurality of separated positions to the substrate as the substrate passes over said each position, to receive reflected light from the substrate as the substrate passes over said each position, and to direct the reflected light from each of the plurality of separated positions to the common detector.

Endpoint control of multiple substrates of varying thickness on the same platen in chemical mechanical polishing

A difference between a first expected required polish time for a first substrate and a second expected required polish time for a second substrate is determined using a first pre-polish thickness and a second pre-polish thickness measured at an in-line metrology station. A duration of an initial period is determined based on the difference between the first expected required polish time and the second expected required polish time. For the initial period at a beginning of a polishing operation, no pressure is applied to whichever of the first substrate and the second substrate has a lesser expected required polish time while simultaneously pressure is applied to whichever of the first substrate and the second substrate has a greater expected required polish time. After the initial period, pressure is applied to both the first substrate and the second substrate.

WAFER EDGE CHARACTERIZATION BY SUCCESSIVE RADIUS MEASUREMENTS USING A SENSOR

PURPOSE: A system for grinding and method are provided to measure the thickness of substrate by utilizing a sensor and to efficiently control the polishing of the polishing of a corresponding substrate or the subsequent substrates. CONSTITUTION: The polishing device comprises one or more polishing stations. The polishing station is operated by a plurality of polishing parameters. The in-line monitoring system comprises the substrate holder and the sensor(102). The sensor produces a signal based on the layer thickness of substrate. The sensor produces the signal about the measured value at the locations separated into more than 3 angularly. The controller controls at least one among a plurality of polishing parameters in response to signal. © KIPO 2009 ...

METHOD AND APPARATUS FOR CHEMICAL MECHANICAL POLISHING WITH AN EDDY CURRENT MONITORING SYSTEM

A polishing system (20) can have a rotatable platen (24), a polishing pad (30) secured to the platen, a carrier head (10) to hold a substrate against the polishing pad, and an eddy current monitoring system including a coil or ferromagnetic body that extends at least partially through the polishing pad. A polishing pad can have a polishing layer and a coil or ferromagnetic body secured to the polishing layer. Recesses can be formed in a transparent window in the polishing pad. © KIPO & WIPO 2007 ...

Spectrographic monitoring of a substrate during processing using index values

Methods, systems, and apparatus for spectrographic monitoring of a substrate during chemical mechanical polishing are described. In one aspect, a computer-implemented method includes storing a library having a plurality of reference spectra, each reference spectrum of the plurality of reference spectra having a stored associated index value, measuring a sequence of spectra in-situ during polishing to obtain measured spectra, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum to generate a sequence of best matching reference spectra, determining the associated index value for each best matching spectrum from the sequence of best matching reference spectra to generate a sequence of index values, fitting a linear function to the sequence of index values, and halting the polishing either when the linear function matches or exceeds a target index or when the associated index value from the determining step matches or exceeds the target index.

Friction sensor for polishing system

A system, method and apparatus to monitor a frictional coefficient of a substrate undergoing polishing is described. A polishing pad assembly includes a polishing layer including a polishing surface, and a substrate contacting member flexibly coupled to the polishing layer having a top surface to contact an exposed surface of a substrate. At least a portion of the top surface is substantially coplanar with the polishing surface. A sensor is provided to measure a lateral displacement of the substrate contacting member. Some embodiments may provide accurate endpoint detection during chemical mechanical polishing to indicate the exposure of an underlying layer.

Polishing system with in-line and in-situ metrology

A computer-implemented method for process control in chemical mechanical polishing in which an initial pre-polishing thickness of a substrate is measured at a metrology station, a parameter of an endpoint algorithm is determined from the initial thickness of the substrate, a substrates is polished at a polishing station, and polishing stops when an endpoint criterion is detected using the endpoint algorithm.

System for Endpoint Detection with Polishing Pad

A method of forming a polishing pad with a polishing layer having a polishing surface and a back surface. A plurality of grooves are formed on the polishing surface, and an indentation is formed in the back surface of the polishing layer. A region on the polishing surface corresponding to the indentation in the back surface is free of grooves or has shallower grooves.

DATA PROCESSING FOR MONITORING CHEMICAL MECHANICAL POLISHING

Methods and apparatus to implement techniques for monitoring polishing a substrate. Two or more data points are acquired, where each data point has a value affected by features inside a sensing region of a sensor and corresponds to a relative position of the substrate (10) and the sensor as the sensing region traverses through the substrate. A set of reference points is used to modify the acquired data points. The modification compensates for distortions in the acquired data points caused by the sensing region traversing through the substrate. Based on the modified data points, a local property of the substrate is evaluated to monitor polishing. © KIPO & WIPO 2007 ...

WAFER EDGE CHARACTERIZATION BY SUCCESSIVE RADIUS MEASUREMENTS

Systems and methods for performing one or more measurements of a substrate at one or more radii along the substrate are described. Thickness measurements taken at various radii along the substrate can be averaged together to obtain an average value that reflects an overall substrate thickness. A more accurate measurement of the overall substrate thickness can be obtained by performing multiple measurements and averaging the measurements together. Using the average value, polishing can be adjusted to ensure that the substrate achieves a desired planarized thickness profile.

Residue Detection with Spectrographic Sensor

Detecting residue of a filler material over a patterned underlying layer includes causing relative motion between a probe of an optical metrology system and a substrate, obtaining a plurality of measured spectra with the optical metrology system through the probe from a plurality of different measurement spots within an area on the substrate, comparing each of the plurality of measured spectra to a reference spectrum to generate a plurality of similarity values, the reference spectrum being a spectrum reflected from the filler material, combining the similarity values to generate a scalar value, and determining the presence of residue based on the scalar value. 1. A method of detecting residue of a filler material over a patterned underlying layer , comprising:causing relative motion between a probe of an optical metrology system and a substrate;obtaining a plurality of measured spectra with the optical metrology system through the probe from a plurality of different measurement spots within an area on the substrate;comparing each of the plurality of measured spectra to a reference spectrum to generate a plurality of similarity values, the reference spectrum being a spectrum reflected from the filler material;combining the similarity values to generate a scalar value; anddetermining the presence of residue based on the scalar value.2. The method of claim 1 , wherein the substrate comprises a plurality of dies claim 1 , and the area is substantially equal to an area of one of the dies.3. The method of claim 1 , wherein the plurality of different measurement spots comprises at least 100 measurement spots.4. The method of claim 1 , wherein the plurality of different measurement are distributed with substantially uniform density across the area.5. The method of claim 1 , wherein causing relative motion comprises holding the substrate in a fixed position in a carrier head and moving the probe.6. The method of claim 5 , wherein moving the probe comprises moving the probe ...

EDDY CURRENT SYSTEM FOR IN-SITU PROFILE MEASUREMENT

An eddy current monitoring system may include an elongated core. One or more coils may be coupled with the elongated core for producing an oscillating magnetic field that may couple with one or more conductive regions on a wafer. The core may be translated relative to the wafer to provide improved resolution while maintaining sufficient signal strength. An eddy current monitoring system may include a DC-coupled marginal oscillator for producing an oscillating magnetic field at a resonant frequency, where the resonant frequency may change as a result of changes to one or more conductive regions. Eddy current monitoring systems may be used to enable real-time profile control. © KIPO & WIPO 2007 ...

Eddy current system for in-situ profile measurement

An eddy current monitoring system may include an elongated core. One or more coils may be coupled with the elongated core for producing an oscillating magnetic field that may couple with one or more conductive regions on a wafer. The core may be translated relative to the wafer to provide improved resolution while maintaining sufficient signal strength. An eddy current monitoring system may include a DC-coupled marginal oscillator for producing an oscillating magnetic field at a resonant frequency, where the resonant frequency may change as a result of changes to one or more conductive regions. Eddy current monitoring systems may be used to enable real-time profile control.

Adjusting polishing rates by using spectrographic monitoring of a substrate during processing

A computer-implemented method includes receiving a sequence of current spectra of reflected light from a substrate; comparing each current spectrum from the sequence of current spectra to a plurality of reference spectra from a reference spectra library to generate a sequence of best-match reference spectra; determining a goodness of fit for the sequence of best-match reference spectra; and determining at least one of whether to adjust a polishing rate or an adjustment for the polishing rate, based on the goodness of fit.

INTEGRATED ENDPOINT DETECTION SYSTEM WITH OPTICAL AND EDDY CURRENT MONITORING

A chemical mechanical polishing apparatus (20) and method can use an eddy current monitoring system (40) and an optical monitoring system (140). Signals from the monitoring systems can be combined on an output line and extracted by a computer. A thickness of a polishing pad (30) can be calculated. The eddy current monitoring system (40) and optical monitoring system (140) can measure substantially the same location on the substrate. © KIPO & WIPO 2007 ...

In-situ substrate imaging

Methods and products, including computer program products, for endpoint determination. An image of a portion of a substrate is captured in-situ, where the image includes optical information that depends on a thickness of a substrate layer. The image is examined to find a location on the substrate, and a process endpoint is determined using a portion of the optical information that corresponds to the location.

Using Spectra to Determine Polishing Endpoints

Methods of determining a polishing endpoint are described using spectra obtained during a polishing sequence. In particular, techniques for using only desired spectra, faster searching methods and more robust rate determination methods are described.

In-situ monitoring system with monitoring of elongated region

A method of chemical mechanical polishing a substrate includes polishing a layer on the substrate at a polishing station, monitoring the layer during polishing at the polishing station with an in-situ monitoring system, the in-situ monitoring system monitoring an elongated region and generating a measured signal, computing an angle between a primary axis of the elongated region and a tangent to an edge of the substrate, modifying the measured signal based on the angle to generate a modified signal, and at least one of detecting a polishing endpoint or modifying a polishing parameter based on the modified signal.

HIGH SENSITIVITY EDDY CURRENT MONITORING SYSTEM

A method of chemical mechanical polishing a substrate includes polishing a metal layer on the substrate at a polishing station, monitoring thickness of the metal layer during polishing at the polishing station with an eddy current monitoring system, and controlling pressures applied by a carrier head to the substrate during polishing of the metal layer at the polishing station based on thickness measurements of the metal layer from the eddy current monitoring system to reduce differences between an expected thickness profile of the metal layer and a target profile, wherein the metal layer has a resistivity greater than 700 ohm Angstroms.

DETERMINATION OF WAFER ANGULAR POSITION FOR IN-SEQUENCE METROLOGY

A polishing apparatus includes a carrier head configured to hold a wafer in a first plane, the wafer having a perimeter and a fiducial, a drive shaft having an axis perpendicular to the first plane and configured to rotate the carrier head about the axis, a light source configured to direct light onto an outer face of the wafer at a position adjacent the perimeter of the wafer; a detector configured to detect the light collected from the wafer while the drive shaft rotates the carrier head and the wafer; and a controller configured to receive a first signal indicating an angular position of the drive shaft and receive a second signal from the detector, the controller configured to determine based on the first signal and the second signal an angular position of the fiducial with respect the carrier head. 1. A polishing apparatus , comprisinga carrier head configured to hold a wafer in a first plane with an inner face of the wafer abutting a support structure of the carrier head, the wafer having a perimeter and a fiducial defined by removal of a portion of the wafer or by having an optically distinct marking at a specific angular position;a drive shaft having an axis perpendicular to the first plane, the drive shaft being connected to the carrier head and configured to rotate the carrier head about the axis;a light source configured to direct light onto an outer face of the wafer at a position adjacent the perimeter of the wafer;a detector configured to detect the light collected from the wafer while the drive shaft rotates the carrier head and the wafer; anda controller configured to receive a first signal indicating an angular position of the drive shaft and receive a second signal from the detector, the controller configured to determine based on the first signal and the second signal an angular position of the fiducial with respect the carrier head.2. The polishing apparatus of claim 1 , wherein the detector is a spectrometer and the second signal comprises a ...

Combined eddy current sensing and optical monitoring for chemical mechanical polishing

A chemical mechanical polishing apparatus has a polishing pad, a carrier to hold a substrate against a first side of the polishing surface, and a motor coupled to at least one of the polishing pad and carrier head for generating relative motion therebetween. An eddy current monitoring system is positioned to generate an alternating magnetic field in proximity to the substrate, an optical monitoring system generates a light beam and detects reflections of the light beam from the substrate, and a controller receives signals from the eddy current monitoring system and the optical monitoring system.

Using spectra to determine polishing endpoints

Methods of determining a polishing endpoint are described using spectra obtained during a polishing sequence. In particular, techniques for using only desired spectra, faster searching methods and more robust rate determination methods are described.

Multi-platen multi-head polishing architecture

A polishing apparatus includes a plurality of stations supported on a platform, the plurality of stations including at least two polishing stations and a transfer station, each polishing station including a platen to support a polishing pad, a plurality of carrier heads suspended from and movable along a track such that each polishing station is selectively positionable at the stations, and a controller configured to control motion of the carrier heads along the track such that during polishing at each polishing station only a single carrier head is positioned in the polishing station.

POLISHING SYSTEM WITH IN-LINE AND IN-SITU METROLOGY

A computer-implemented method for process control in chemical mechanical polishing in which an initial pre-polishing thickness of a substrate is measured at a metrology station, a parameter of an endpoint algorithm is determined from the initial thickness of the substrate, a substrates is polished at a polishing station, and polishing stops when an endpoint criterion is detected using the endpoint algorithm.

ENDPOINT CONTROL OF MULTIPLE SUBSTRATES OF VARYING THICKNESS ON THE SAME PLATEN IN CHEMICAL MECHANICAL POLISHING

A difference between a first expected required polish time for a first substrate and a second expected required polish time for a second substrate is determined using a first pre-polish thickness and a second pre-polish thickness measured at an in-line metrology station. A duration of an initial period is determined based on the difference between the first expected required polish time and the second expected required polish time. For the initial period at a beginning of a polishing operation, no pressure is applied to whichever of the first substrate and the second substrate has a lesser expected required polish time while simultaneously pressure is applied to whichever of the first substrate and the second substrate has a greater expected required polish time. After the initial period, pressure is applied to both the first substrate and the second substrate.

INTEGRATED ENDPOINT DETECTION SYSTEM WITH OPTICAL AND EDDY CURRENT MONITORING

A chemical mechanical polishing apparatus (20) and method can use an eddy current monitoring system (40) and an optical monitoring system (140). Signals from the monitoring systems can be combined on an output line and extracted by a computer. A thickness of a polishing pad (30) can be calculated. The eddy current monitoring system (40) and optical monitoring system (140) can measure substantially the same location on the substrate. © KIPO & WIPO 2008 ...

Chemical mechanical polishing apparatus with non-conductive elements

Conductive elements of a chemical mechanical polishing system may generate undesired eddy currents under the influence of a time-dependent magnetic field used in an eddy current monitoring system. To improve the accuracy of an eddy current monitoring system, elements that may contribute an undesired signal to the sensed eddy current signal may be fabricated from a non-conductive material such as plastic or ceramic. In some implementations, elements may be fabricated from non-magnetic materials.

Polishing system with in-line and in-situ metrology

A computer-implemented method for process control in chemical mechanical polishing in which an initial pre-polishing thickness of a substrate is measured at a metrology station, a parameter of an endpoint algorithm is determined from the initial thickness of the substrate, a substrates is polished at a polishing station, and polishing stops when an endpoint criterion is detected using the endpoint algorithm.

Polishing pad for endpoint detection and related methods

A polishing pad has a polishing layer with a polishing surface and a back surface. A plurality of grooves are formed on the polishing surface, and an indentation is formed in the back surface of the polishing layer. A region on the polishing surface corresponding to the indentation in the back surface is free of grooves or has shallower grooves.

Spectra based endpointing for chemical mechanical polishing

Methods and apparatus for spectrum-based endpointing. An endpointing method includes selecting two or more reference spectra. Each reference spectrum is a spectrum of white light reflected from a film of interest on a first substrate and has a thickness greater than a target thickness. The reference spectra is selected for particular spectra-based endpoint determination logic so that the target thickness is achieved when endpoint is called by applying the particular spectra-based endpoint logic. The method includes obtaining two or more current spectra. Each current spectrum is a spectrum of white light reflected from a film of interest on a second substrate when the film of interest is being subjected to a polishing step and has a current thickness that is greater than the target thickness. The method includes determining, for the second substrate, when an endpoint of the polishing step has been achieved.

TECHNIQUES FOR MATCHING SPECTRA

A method of controlling processing of a substrate includes measuring a spectrum reflected from the substrate, for each partition of a plurality of partitions of the measured spectrum, computing a partition value based on the measured spectrum within the partition to generate a plurality of partition values, for each reference spectrum signature of a plurality of reference spectrum signatures, determining a membership function for each partition, for each partition, computing a membership value based on the membership function for the partition and the partition value for the partition to generate a plurality of groups of membership values with each group of the plurality of groups associated with a reference spectrum signature, selecting a best matching reference spectrum signature from the plurality of reference spectra signatures based on the plurality of groups of membership values, and determining a characterizing value associated with the best matching reference spectrum signature. 1. A method of controlling processing of a substrate , comprising:processing a substrate;measuring a spectrum reflected from the substrate with a spectrographic monitoring system to generate a measured spectrum;for each partition of a plurality of partitions of the measured spectrum, computing a partition value based on the measured spectrum within the partition to generate a plurality of partition values;for each reference spectrum signature of a plurality of reference spectrum signatures, determining a membership function for each partition;for each partition, computing a membership value based on the membership function for the partition and the partition value for the partition to generate a plurality of groups of membership values with each group of the plurality of groups associated with a reference spectrum signature;selecting a best matching reference spectrum signature from the plurality of reference spectra signatures based on the plurality of groups of membership values; ...

Substrate thickness measuring during polishing

A method for determining a polishing endpoint includes obtaining spectra from different zones on a substrate during different times in a polishing sequence, matching the spectra with indexes in a library and using the indexes to determining a polishing rate for each of the different zones from the indexes. An adjusted polishing rate can be determined for one of the zones, which causes the substrate to have a desired profile when the polishing end time is reached.

Integrated endpoint detection system with optical and eddy current monitoring

A chemical mechanical polishing apparatus and method can use an eddy current monitoring system and an optical monitoring system. Signals from the monitoring systems can be combined on an output line and extracted by a computer. A thickness of a polishing pad can be calculated. The eddy current monitoring system and optical monitoring system can measure substantially the same location on the substrate.

Polishing pads useful for endpoint detection in chemical mechanical polishing

A polishing system (20) can have a rotatable platen (24), a polishing pad (30) secured to the platen, a carrier head (10) to hold a substrate against the polishing pad, and an eddy current monitoring system including a coil or ferromagnetic body that extends at least partially through the polishing pad. A polishing pad can have a polishing layer and a coil or ferromagnetic body secured to the polishing layer. Recesses can be formed in a transparent window in the polishing pad.

Polishing pad for endpoint detection and related methods

METHOD AND APPARATUS FOR GENERATING LIBRARY OF SPECTRA AND HIGH-THROUGHPUT MEASUREMENT SYSTEM, CAPABLE OF GENERATING LIBRARY FROM REFERENCE SUBSTRATE TO PROCESS WAFER PRODUCT

PURPOSE: A method and an apparatus for generating a library of spectra and a high-throughput measurement system are provided to optically monitor substrates during a chemical and mechanical polishing process. CONSTITUTION: A method for generating a library of spectra comprises the following steps of: measuring features of a substrate in a plurality of well-defined points of a reference substrate; measuring spectra in plural measurement points of the reference substrate; associating the measures spectra with the features of the substrate; storing coordinates of the well-defined points; and coordinates of the measured points. The step of associating the measures spectra with the features of the substrate comprises the steps of determining a well-defined point in the vicinity of a specific measured point and associating the features of the substrate of the determined well-defined point with spectra of the specific measured point. © KIPO 2008 ...

Feedback control of polishing using optical detection of clearance

A method of controlling polishing includes polishing a first substrate having an overlying layer on an underlying layer or layer structure. During polishing, the substrate is monitored with an in-situ monitoring system to generate a sequence of measurements. The measurements are sorted into groups, each group associated with a different zone of a plurality of zones on the substrate. For each zone, a time at which the overlying layer is cleared is determined based on the measurements from the associated group. At least one second adjusted polishing pressure for at least zone is calculated based on a pressure applied in the at least one zone during polishing the substrate, the time for the at least one zone, and the time for another zone. A second substrate is polished using the at least one adjusted polishing pressure.

GROUPING SPECTRAL DATA FROM POLISHING SUBSTRATES

Among other things, a computer-based method is described. The method comprises receiving, by one or more computers, a plurality of measured spectra reflected from a substrate at a plurality of different positions on the substrate. The substrate comprises at least two regions having different structural features. The method also comprises performing, by the one or more computers, a clustering algorithm on the plurality of measured spectra to separate the plurality of measured spectra into a number of groups based on the spectral characteristics of the plurality of measured spectra; selecting one of the number of groups to provide a selected group having a subset of spectra from the plurality of measured spectra; and determining, in the one or more computers, at least one characterizing value for the substrate based on the subset of spectra of the selected group. COPYRIGHT KIPO 2015 (190) Controller ...

Method and apparatus of eddy current monitoring for chemical mechanical polishing

A polishing system can have a rotatable platen, a polishing pad secured to the platen, a carrier head to hold a substrate against the polishing pad, and an eddy current monitoring system including a coil or ferromagnetic body that extends at least partially through the polishing pad. A polishing pad can have a polishing layer and a coil or ferromagnetic body secured to the polishing layer. Recesses can be formed in a transparent window in the polishing pad.

Reducing polishing pad deformation

A chemical mechanical polishing pad is described. A chemical mechanical polishing pad has an outer layer that includes a polishing surface, a first thinned region defined by a recess on a bottom surface of the pad, a first thick region surrounding the first thinned region, a second thinned region surrounding the first thick region, and a second thick region surrounding the second thinned region. The first thick region is not vertically extendable. The second thinned region defines one or more flexure mechanisms configured to make the first thinned region and the first thick region movable relative to the second thick region in a direction parallel or substantially parallel to the polishing surface.

USING OPTICAL METROLOGY FOR WITHIN WAFER FEED FORWARD PROCESS CONTROL

A method of controlling the polishing of a substrate includes polishing a substrate on a first platen using a first set of parameters, obtaining first and second sequences of measured spectra from first and second regions of the substrate with an in-situ optical monitoring system, generating first and second sequences of values from the first and second sequences of measured spectra, fitting first and second linear functions to the first and second sequences of values, determining a difference between the first linear function and the second linear function, adjusting at least one parameter of a second set of parameters based on the difference, and polishing the substrate on a second platen using the adjusted parameter. 1. A method of controlling the chemical mechanical polishing of a substrate , comprising:polishing a substrate on a first platen using a first set of polishing parameters;obtaining a first sequence of measured spectra with an in-situ optical monitoring system, each measured spectrum from the first sequence of measured spectra being a spectrum of light reflected from a first region of the substrate;generating a first sequence of values from the first sequence of measured spectra;fitting a first function to the first sequence of values;obtaining a second sequence of measured spectra with the in-situ optical monitoring system, each measured spectrum from the second sequence of measured spectra being a spectrum of light reflected from a second region of the substrate;generating a second sequence of values from the second sequence of measured spectra;fitting a second function to the second sequence of values;determining an adjustment for at least one polishing parameter of a second set of polishing parameters based on a difference between the first function and the second function so as to reduce an expected difference between an expected first function for the first region and an expected second function for the second region in polishing of the ...

PATH FOR PROBE OF SPECTROGRAPHIC METROLOGY SYSTEM

A method of operating a polishing system includes polishing a substrate at a polishing station, the substrate held by a carrier head during polishing, transporting the substrate to an in-sequence optical metrology system positioned between the polishing station and another polishing station or a transfer station, measuring a plurality of spectra reflected from the substrate with a probe of the optical metrology system while moving the carrier head to cause the probe to traverse a path across the substrate and while the probe remains stationary, the path across the substrate comprising either a plurality of concentric circles or a plurality of substantially radially aligned arcuate segments, and adjusting a polishing endpoint or a polishing parameter of the polishing system based on one or more characterizing values generated based on at least some of the plurality of spectra. 1. A method of operating a polishing system , comprising:polishing a substrate at a polishing station, the substrate held by a carrier head during polishing;transporting the substrate to an in-sequence optical metrology system positioned between the polishing station and another polishing station or a transfer station;measuring a plurality of spectra reflected from the substrate with a probe of the optical metrology system while moving the carrier head to cause the probe to traverse a path across the substrate and while the probe remains stationary, the path across the substrate comprising either a plurality of concentric circles or a plurality of substantially radially aligned arcuate segments; andadjusting a polishing endpoint or a polishing parameter of the polishing system based on one or more characterizing values generated based on at least some of the plurality of spectra.2. The method of claim 1 , comprising polishing the substrate after measuring the plurality of spectra.3. The method of claim 1 , wherein the path comprises the plurality of concentric circles.4. The method of claim 1 , ...

REFLECTIVITY MEASUREMENTS DURING POLISHING USING A CAMERA

A substrate polishing system includes a platen to support a polishing surface, a carrier head configured to hold a substrate against the polishing surface during polishing, a light source configured to direct a light beam onto a surface of the substrate, a detector including an array of detection elements, and a controller. The detector is configured to detect reflections of the light beam from an area of the surface, and is configured to generate an image having pixels representing regions on the substrate having a length less than 0.1 mm. The controller is configured to receive the image and to detect clearance of a metal layer from an underlying layer on the substrate based on the image. 1. A substrate polishing system , comprising:a platen to support a polishing surface;a carrier head configured to hold a substrate against the polishing surface during polishing;a light source configured to direct a light beam onto a surface of the substrate;a detector including an array of detection elements, wherein the detector is configured to detect reflections of the light beam from an area of the surface, and wherein the detector is configured to generate an image having pixels representing regions on the substrate having a length less than 0.1 mm; anda controller configured to receive the image and to detect clearance of a metal layer from an underlying layer on the substrate based on the image.2. The polishing system of claim 1 , wherein the detector comprises a linescan camera.3. The polishing system of claim 2 , wherein the detector is configured such that the image has pixels representing regions on the substrate having a width less than 0.1 mm.4. The polishing system of claim 1 , wherein the area is between 5 and 25 mm long.5. The polishing system of claim 1 , wherein the detector comprises at least 1024 detection elements.6. The polishing system of claim 5 , wherein the detector is configured to operate at a frame rate at least 5 kHz.7. The polishing system of claim ...

Polishing system with in-line and in-situ metrology

A computer-implemented method for process control in chemical mechanical polishing in which an initial pre-polishing thickness of a substrate is measured at a metrology station, a parameter of an endpoint algorithm is determined from the initial thickness of the substrate, a substrates is polished at a polishing station, and polishing stops when an endpoint criterion is detected using the endpoint algorithm.

Endpoint control of multiple-wafer chemical mechanical polishing

A computer-implemented method includes polishing substrates simultaneously in a polishing apparatus. Each substrate has a polishing rate independently controllable by an independently variable polishing parameter. Measurement data that varies with the thickness of each of the substrates is acquired from each of the substrates during polishing with an in-situ monitoring system. A projected thickness that each substrate will have at a target time is determined based on the measurement data. The polishing parameter for at least one substrate is adjusted to adjust the polishing rate of the at least one substrate such that the substrates have closer to the same thickness at the target time than without the adjustment.

POLISHING PAD FOR ENDPOINT DETECTION AND RELATED METHODS

A polishing pad has a polishing layer (22) with a polishing surface (24) and a back surface. A plurality of grooves (28b) are formed on the polishing surface, and an indentation (52) is formed in the back surface of the polishing layer. A region on the polishing surface corresponding to the indentation in the back surface is free of grooves or has shallower grooves (28a). © KIPO & WIPO 2007 ...

Spectra Based Endpointing for Chemical Mechanical Polishing

A computer implemented method of monitoring a polishing process includes, for each sweep of a plurality of sweeps of an optical sensor across a substrate undergoing polishing, obtaining a plurality of current spectra, each current spectrum of the plurality of current spectra being a spectrum resulting from reflection of white light from the substrate, for each sweep of the plurality of sweeps, determining a difference between each current spectrum and each reference spectrum of a plurality of reference spectra to generate a plurality of differences, for each sweep of the plurality of sweeps, determining a smallest difference of the plurality of differences, thus generating a sequence of smallest difference, and determining a polishing endpoint based on the sequence of smallest differences. 117-. (canceled)18. A computer program product encoded a machine-readable storage device , the product comprising instructions operable to cause a processor to:for each sweep of a plurality of sweeps of an optical sensor across a substrate undergoing polishing, receive a plurality of current spectra, each current spectrum of the plurality of current spectra being a spectrum resulting from reflection of white light from the substrate;for each sweep of the plurality of sweeps, determine a difference between each current spectrum and each reference spectrum of a plurality of reference spectra to generate a plurality of differences;for each sweep of the plurality of sweeps, determine a smallest difference of the plurality of differences, thus generating a sequence of smallest difference; anddetermine a polishing endpoint based on the sequence of smallest differences.19. The computer program product of claim 18 , wherein the instructions to determine the polishing endpoint comprise instructions to detect that the sequence of smallest differences has reached a threshold value.20. The computer program product of claim 18 , wherein the instructions to determine the polishing endpoint ...

GST Film Thickness Monitoring

In polishing a substrate having a layer of GST disposed over an underlying layer, during polishing, a non-polarized light beam is directed onto the layer of GST. The non-polarized light beam reflects from the first substrate to generate a reflected light beam having an infra-red component. A sequence of measurements of intensity of the infra-red component of the reflected light beam are generated, and, in a processor, a time at which the sequence of measurements exhibits a predefined feature is determined.

Automatic Gain Control

Methods and apparatus for automatic gain control. A film on a substrate is polished by a chemical mechanical polisher that includes a polishing pad and an in-situ monitoring system. The polishing pad includes a first portion, and the in-situ monitoring system includes a light source and a light detector. The light source emits light, and light emitted from the light source is directed through the first portion and to a surface of the film being polished. Light reflecting from the surface of the film being polished and passing through the first portion is received at the light detector. An electronic signal is generated based on the light received at the light detector. When the electronic signal is evaluated not to satisfy one or more constraints, a gain for the light detector is adjusted so that the electronic signal would satisfy the one or more constraints. 1. A computer-program product , tangibly stored on non-transitory machine-readable medium , the product comprising instructions operable to cause a chemical mechanical polisher to:during a polishing step in which a film on a substrate is polished by a chemical mechanical polisher, cause an in-situ monitoring system to monitor the film being polished through a first portion of a polishing pad of the chemical mechanical polisher;during the polishing step, generate a first electronic signal from a detector in the in-situ monitoring system, the in-situ monitoring system having a gain, the detector sensitive to a characteristic of the film being polished;during a first period in the polishing step, amplify the first electronic signal with the gain set to a first value to generate an amplified first electronic signal;during the polishing step, evaluate whether an amplitude of the amplified first electronic signal is within a first target range;when the amplified first electronic signal is evaluated not to satisfy the one or more constraints, calculate a different second value for the gain such that amplifying the ...

Optical monitoring in a two-step chemical mechanical polishing process

An optical monitoring system for a two-step polishing process which generates a reflectance trace for each of plurality of radial zones. The CMP apparatus may switch from a high-selectivity slurry to a low-selectivity slurry when any of the reflectance traces indicate initial clearance of the metal layer, and polishing may halt when all of the reflectance traces indicate that oxide layer has been completely exposed.

Substrate monitoring during chemical mechanical polishing

Methods and apparatus for monitoring a substrate surface during chemical mechanical polishing are disclosed.

PEAK-BASED ENDPOINTING FOR CHEMICAL MECHANICAL POLISHING

A polishing system receives one or more target parameters for a selected peak in a spectrum of light, polishes a substrate, measures a current spectrum of light reflected from the substrate while the substrate is being polished, identifies the selected peak in the current spectrum, measures one or more current parameters of the selected peak in the current spectrum, compares the current parameters of the selected peak to the target parameters, and ceases to polish the substrate when the current parameters and the target parameters have a pre defined relationship. 1. A polishing endpoint detection system , comprising:a light source to direct a light to a substrate while the substrate is being polished;a spectrometer to measure a sequence of current spectra of light reflected from the substrate while the substrate is being polished; and store a predetermined criterion for detecting an endpoint using a selected peak or valley in a spectrum of light,', 'receive the sequence of current spectra from the spectrometer,', 'identify the selected peak or valley in each current spectrum in the sequence of current spectra, wherein the selected peak or valley persists with at least an evolving location or width through the sequence of current spectra,', 'measure one or more of a current location and a current width of the selected peak or valley in the current spectrum, and', 'generate a signal to halt polishing of the substrate when the current location or the current width, respectively, of the selected peak or valley satisfies the predetermined criterion., 'a controller configured to'}2. The system of claim 1 , wherein the controller is configured such that for each current spectrum in the sequence of current spectra claim 1 , a current width of the selected peak or valley in the current spectrum is measured.3. The system of claim 1 , wherein the controller is configured such that for each current spectrum in the sequence of current spectra claim 1 , wherein for each current ...

Determining Physical Property of Substrate

A method of determining a physical property of a substrate includes recording a first spectrum obtained from a substrate, the first spectrum being obtained during a polishing process that alters a physical property of the substrate. The method includes identifying, in a database, at least one of several previously recorded spectra that is similar to the recorded first spectrum. Each of the spectra in the database has a physical property value associated therewith. The method includes generating a signal indicating that a first value of the physical property is associated with the first spectrum, the first value being determined using the physical property value associated with the identified previously recorded spectrum in the database. A system for determining a physical property of a substrate includes a polishing machine, an endpoint determining module, and a database.

Polishing pad and system with window support

A polishing system includes a polishing pad having a solid light-transmissive window, an optical fiber having an end, and a spacer having a vertical aperture therethrough. A bottom surface of the spacer contacts the end of the optical fiber, a top surface of the spacer contacts the underside of the window, and the vertical aperture is aligned with the optical fiber.

Determining Physical Property of Substrate

A method of determining a physical property of a substrate includes recording a first spectrum obtained from a substrate, the first spectrum being obtained during a polishing process that alters a physical property of the substrate. The method includes identifying, in a database, at least one of several previously recorded spectra that is similar to the recorded first spectrum. Each of the spectra in the database has a physical property value associated therewith. The method includes generating a signal indicating that a first value of the physical property is associated with the first spectrum, the first value being determined using the physical property value associated with the identified previously recorded spectrum in the database. A system for determining a physical property of a substrate includes a polishing machine, an endpoint determining module, and a database.

POLISHING PAD WITH WINDOW HAVING MULTIPLE PORTIONS

A polishing pad has an opaque polishing layer with an aperture therethrough and a polishing surface, and a solid light-transmissive window in the aperture. The solid light-transmissive window includes an outer portion secured to the polishing layer and an inner portion secured to the outer portion. The outer portion has a upper surface recessed relative to the polishing surface, whereas the inner portion has an upper surface that is substantially co-planar with the polishing surface.

Selecting reference libraries for monitoring of multiple zones on a substrate

A method of configuring a polishing monitoring system includes receiving user input selecting a plurality of libraries, each library of the plurality of libraries comprising a plurality of reference spectra for use in matching to measured spectra during polishing, each reference spectrum of the plurality of reference spectra having an associated index value, for a first zone of a substrate, receiving user input selecting a first subset of the plurality of libraries, and for a second zone of the substrate, receiving user input selecting a second subset of the plurality of libraries.

Multi-platen multi-head polishing architecture

A polishing apparatus includes a plurality of stations supported on a platform, the plurality of stations including at least two polishing stations and a transfer station, each polishing station including a platen to support a polishing pad, a plurality of carrier heads suspended from and movable along a track such that each polishing station is selectively positionable at the stations, and a controller configured, to control motion of the carrier heads along the track such that during polishing at each polishing station only a single carrier head is positioned in the polishing station.

High sensitivity eddy current monitoring system

A method of chemical mechanical polishing a substrate includes polishing a metal layer on the substrate at a polishing station, monitoring thickness of the metal layer during polishing at the polishing station with an eddy current monitoring system, and controlling pressures applied by a carrier head to the substrate during polishing of the metal layer at the polishing station based on thickness measurements of the metal layer from the eddy current monitoring system to reduce differences between an expected thickness profile of the metal layer and a target profile, wherein the metal layer has a resistivity greater than 700 ohm Angstroms.

DETERMINING PHYSICAL PROPERTY OF SUBSTRATE

A method of determining a physical property of a substrate includes recording a first spectrum obtained from a substrate, the first spectrum being obtained during a polishing process that alters a physical property of the substrate. The method includes identifying, in a database, at least one of several previously recorded spectra that is similar to the recorded first spectrum. Each of the spectra in the database has a physical property value associated therewith. The method includes generating a signal indicating that a first value of the physical property is associated with the first spectrum, the first value being determined using the physical property value associated with the identified previously recorded spectrum in the database. A system for determining a physical property of a substrate includes a polishing machine, an endpoint determining module, and a database.

REDUCING NOISE IN SPECTRAL DATA FROM POLISHING SUBSTRATES

Among other things, a machine based method comprises representing a plurality of spectra reflected from one or more substrates at a plurality of different positions on the one or more substrates in the form of a first matrix; decomposing, by one or more computers, the first matrix into products of at least two component matrixes of a first set of component matrixes; reducing dimensions of each of the at least two component matrixes to produce a second set of component matrixes containing the at least two matrixes with reduced dimensions; and generating, by the one or more computers, a second matrix by taking a product of the matrixes of the second set of component matrixes. COPYRIGHT KIPO 2015 (190) Controller ...

Control Of Overpolishing Of Multiple Substrates On the Same Platen In Chemical Mechanical Polishing

A polishing method includes simultaneously polishing a first substrate and a second substrate on the same polishing pad, storing a default overpolishing time, determining first and second polishing endpoint times of the first and substrates with the in-situ monitoring system, determining a difference between the first and second polishing endpoint times, and determining whether the difference exceeds a threshold. If the difference is less than the threshold, then an overpolishing stop time is calculated and polishing of the first substrate and the second substrates is halted simultaneously at the overpolishing stop time. If the difference is greater than the threshold, then first and second overpolishing stop times that equal the first and second endpoint times plus the default overpolishing time are calculated, and polishing of the first and second substrates is halted at the first and second overpolishing stop times, respectively. 1. A polishing method , comprising:simultaneously polishing a first substrate and a second substrate on the same polishing pad;storing a default overpolishing time;monitoring the first substrate and the second substrate during polishing with an in-situ monitoring system;determining a first polishing endpoint time of the first substrate with the in-situ monitoring system;determining a second polishing endpoint time of the second substrate with the in-situ monitoring system;determining a difference between the first polishing endpoint time and the second endpoint time;determining whether the difference exceeds a threshold; and if the difference is less than the threshold then calculating an overpolishing stop time and halting polishing of the first substrate and the second substrates simultaneously at the overpolishing stop time, and', 'if the difference is greater than the threshold then calculating a first overpolishing stop time that equals the first endpoint time plus the default overpolishing time and calculating a second ...

USING SPECTRA TO DETERMINE POLISHING ENDPOINTS

Methods of determining a polishing endpoint are described using spectra obtained during a polishing sequence. In particular, techniques for using only desired spectra, faster searching methods and more robust rate determination methods are described. COPYRIGHT KIPO & WIPO 2010 ...

Feedback Control of Polishing Using Optical Detection of Clearance

A method of controlling polishing includes polishing a first substrate having an overlying layer on an underlying layer or layer structure. During polishing, the substrate is monitored with an in-situ monitoring system to generate a sequence of measurements. The measurements are sorted into groups, each group associated with a different zone of a plurality of zones on the substrate. For each zone, a time at which the overlying layer is cleared is determined based on the measurements from the associated group. At least one second adjusted polishing pressure for at least zone is calculated based on a pressure applied in the at least one zone during polishing the substrate, the time for the at least one zone, and the time for another zone. A second substrate is polished using the at least one adjusted polishing pressure.

EDDY CURRENT MONITORING OF METAL FEATURES

A method of chemical mechanical polishing a substrate includes polishing a plurality of discrete separated metal features of a layer on the substrate at a polishing station, using an eddy current monitoring system to monitor thickness of the metal features in the layer, and controlling pressures applied by a carrier head to the substrate during polishing of the layer at the polishing station based on thickness measurements of the metal features from the eddy current monitoring system to reduce differences between an expected thickness profile of the metal feature and a target profile. 1. A method of chemical mechanical polishing a substrate , comprising:polishing a plurality of discrete separated metal features of a layer on the substrate at a polishing station;using an eddy current monitoring system to monitor thickness of the metal features in the layer; andcontrolling pressures applied by a carrier head to the substrate during polishing of the layer at the polishing station based on thickness measurements of the metal features from the eddy current monitoring system to reduce differences between an expected thickness profile of the metal feature and a target profile.2. The method of claim 1 , furthering comprising halting polishing the layer when the eddy current monitoring system indicates that a predetermined thickness of the metal features remains on the substrate.3. The method of claim 1 , wherein the target profile is a planar profile and reducing differences improves thickness uniformity of the layer.4. The method of claim 1 , wherein the metal features are separated by a solid dielectric material that laterally surrounds the metal features.5. The method of claim 1 , wherein the metal features are metal-filled trenches in the layer.6. The method of claim 1 , wherein the metal features consist of copper.7. The method of claim 1 , wherein the metal features comprises conductive lines or vias.8. The method of claim 5 , further comprising clearing an overlying ...

IN-SITU ENDPOINT DETECTION AND PROCESS MONITORING METHOD AND APPARATUS FOR CHEMICAL MECHANICAL POLISHING

A chemical mechanical polishing apparatus has a polishing pad (30), a carrier (70) to hold a substrate (10) against a first side of the polishing surface, and a motor coupled to at least one of the polishing pad (30) and carrier head (70) for generating relative motion therebetween. An eddy current monitoring system (40) is positioned to generate an alternating magnetic field in proximity to the substrate (10), an optical monitoring system (140) generates a light beam and detects reflections of the light beam from the substrate (10), and a controller (90) receives signals from the eddy current monitoring system (40) and the optical monitoring system (140). © KIPO & WIPO 2007 ...

DETERMINING COPPER CONCENTRATION IN SPECTRA

Methods of subtracting the copper contribution to spectra obtained from a substrate during chemical mechanical polishing are described.

Polishing pad with window

Polishing pads with a window, systems containing such polishing pads, and processes that use such polishing pads are disclosed. In embodiments, a polishing pad includes a backing layer having an opening, a polishing layer having an opening aligned with the opening in the backing layer, a solid window of a first material in the opening of the polishing layer, a layer of a first adhesive material between the backing layer and the solid window, and a layer of a second adhesive material between the layer of the first adhesive material and the window.

Combined eddy current sensing and optical monitoring for chemical mechanical polishing

A chemical mechanical polishing apparatus has a polishing pad, a carrier to hold a substrate against a first side of the polishing surface, and a motor coupled to at least one of the polishing pad and carrier head for generating relative motion therebetween. An eddy current monitoring system is positioned to generate an alternating magnetic field in proximity to the substrate, an optical monitoring system generates a light beam and detects reflections of the light beam from the substrate, and a controller receives signals from the eddy current monitoring system and the optical monitoring system.

Endpointing detection for chemical mechanical polishing based on spectrometry

Methods and apparatus for spectrum-based endpointing. An endpointing method includes selecting a reference spectrum. The reference spectrum is a spectrum of white light reflected from a film of interest on a first substrate and has a thickness greater than a target thickness. The reference spectrum is empirically selected for particular spectrum-based endpoint determination logic so that the target thickness is achieved when endpoint is called by applying the particular spectrum-based endpoint logic. The method includes obtaining a current spectrum. The current spectrum is a spectrum of white light reflected from a film of interest on a second substrate when the film of interest is being subjected to a polishing step and has a current thickness that is greater than the target thickness. The method includes determining, for the second substrate, when an endpoint of the polishing step has been achieved. The determining is based on the reference and current spectra.

Eddy Current System for In-Situ Profile Measurement

An eddy current monitoring system may include an elongated core. One or more coils may be coupled with the elongated core for producing an oscillating magnetic field that may couple with one or more conductive regions on a wafer. The core may be translated relative to the wafer to provide improved resolution while maintaining sufficient signal strength. An eddy current monitoring system may include a DC-coupled marginal oscillator for producing an oscillating magnetic field at a resonant frequency, where the resonant frequency may change as a result of changes to one or more conductive regions. Eddy current monitoring systems may be used to enable real-time profile control.

Method for determining copper concentration in spectra

The present invention discloses a method for subtracting the contribution of non-dielectric (such as copper) to the substrate spectrum in the period of chemical mechanical polishing, and especially discloses a method for optically determining the amount of area comprising non-dielectric material and determining the concentration of metal (such as copper) which covers the surface of substrate through using a broadband reflection spectrum of surface when a substrate is polished. The invention relates to reliably determining an end point through a spectral interference pattern obtained from the reflection of dielectric area when the adjacent area is covered by metal, wherein, the metal intensively reflect the related full wavelength range and is inclined to shield the reflection spectrum from the adjacent dielectric area.

Data processing for monitoring chemical mechanical polishing

Methods and apparatus to implement techniques for monitoring polishing a substrate. Two or more data points are acquired, where each data point has a value affected by features inside a sensing region of a sensor and corresponds to a relative position of the substrate and the sensor as the sensing region traverses through the substrate. A set of reference points is used to modify the acquired data points. The modification compensates for distortions in the acquired data points caused by the sensing region traversing through the substrate. Based on the modified data points, a local property of the substrate is evaluated to monitor polishing.

Determining copper concentration in spectra

Methods of subtracting the copper contribution to spectra obtained from a substrate during chemical mechanical polishing are described.

Method and apparatus of eddy current monitoring for chemical mechanical polishing

A polishing system can have a rotatable platen, a polishing pad secured to the platen, a carrier head to hold a substrate against the polishing pad, and an eddy current monitoring system including a coil or ferromagnetic body that extends at least partially through the polishing pad. A polishing pad can have a polishing layer and a coil or ferromagnetic body secured to the polishing layer. Recesses can be formed in a transparent window in the polishing pad.

Determining physical property of substrate

A method of determining a physical property of a substrate includes recording a first spectrum obtained from a substrate, the first spectrum being obtained during a polishing process that alters a physical property of the substrate. The method includes identifying, in a database, at least one of several previously recorded spectra that is similar to the recorded first spectrum. Each of the spectra in the database has a physical property value associated therewith. The method includes generating a signal indicating that a first value of the physical property is associated with the first spectrum, the first value being determined using the physical property value associated with the identified previously recorded spectrum in the database. A system for determining a physical property of a substrate includes a polishing machine, an endpoint determining module, and a database.

Optical monitoring in a two-step chemical mechanical polishing process

An optical monitoring system for a two-step polishing process which generates a reflectance trace for each of plurality of radial zones. The CMP apparatus may switch from a high-selectivity slurry to a low-selectivity slurry when any of the reflectance traces indicate initial clearance of the metal layer, and polishing may halt when all of the reflectance traces indicate that oxide layer has been completely exposed. ...

Metrology for chemical mechanical polishing

Methods and apparatus for providing metrology for chemical mechanical polishing. A chemical mechanical polishing system includes a first polishing station, a second polishing station, a transport device, and a first measuring station. The transport device is configured to hold a workpiece during polishing at the first and second polishing stations and to move the workpiece from the first polishing station to the second polishing station. The first measuring station is situated to measure a characteristic of the workpiece when the transport device is holding the workpiece and when the workpiece is not in contact with a polishing pad of any of the first polishing station and the second polishing station.

Reflectivity measurements during polishing using a camera

A substrate polishing system includes a platen to support a polishing surface, a carrier head configured to hold a substrate against the polishing surface during polishing, a light source configured to direct a light beam onto a surface of the substrate, a detector including an array of detection elements, and a controller. The detector is configured to detect reflections of the light beam from an area of the surface, and is configured to generate an image having pixels representing regions on the substrate having a length less than 0.1 mm. The controller is configured to receive the image and to detect clearance of a metal layer from an underlying layer on the substrate based on the image.

CONTROL OF POLISHING OF MULTIPLE SUBSTRATES ON THE SAME PLATEN IN CHEMICAL MECHANICAL POLISHING

A polishing method includes positioning two substrates in contact with the same polishing pad. Prior to commencement of polishing and while the two substrates are in contact with the polishing pad, two starting values are generated from an in-situ monitoring system. Either a starting polishing time or a pressure applied to one of the substrates can be adjusted so that the two substrates have closer endpoint conditions. During polishing the two substrates are monitored with the in-situ monitoring system to generate a two sequences of values, and a polishing endpoint can be detected or an adjustment for a polishing parameter can be based on the two sequences of values. 1. A polishing method , comprising:positioning a first substrate and a second substrate in contact with the same polishing pad;prior to commencement of polishing and while the first substrate and second substrate are in contact with the polishing pad, generating from an in-situ monitoring system a first starting value and a second starting value from the first substrate and the second substrate, respectively;calculating an adjusted first pressure for the first substrate;polishing the first substrate on the polishing pad with the adjusted pressure and polishing the second substrate on the polishing pad with a second pressure;monitoring the first substrate and the second substrate during polishing with the in-situ monitoring system to generate a first sequence of values for the first substrate and a second sequence of values for the second substrate; andat least one of detecting a polishing endpoint for the first substrate and the second substrate or determining an adjustment for a polishing parameter based on the first sequence of values and the second sequence of values.2. The method of claim 1 , wherein calculating the adjusted first pressure comprises a default pressure multiplied by a ratio based on the first starting value and the second starting value.3. The method of claim 2 , wherein the default ...

Spectra based endpointing for chemical mechanical polishing

Methods and apparatus for spectrum-based endpointing. An endpointing method includes selecting two or more reference spectra. Each reference spectrum is a spectrum of white light reflected from a film of interest on a first substrate and has a thickness greater than a target thickness. The reference spectra is selected for particular spectra-based endpoint determination logic so that the target thickness is achieved when endpoint is called by applying the particular spectra-based endpoint logic. The method includes obtaining two or more current spectra. Each current spectrum is a spectrum of white light reflected from a film of interest on a second substrate when the film of interest is being subjected to a polishing step and has a current thickness that is greater than the target thickness. The method includes determining, for the second substrate, when an endpoint of the polishing step has been achieved.

Methods and apparatus for measuring substrate edge thickness during polishing

Systems, methods and apparatus are provided for determining a substrate polishing endpoint. The invention includes a light source adapted to transmit light to an edge of a substrate; one or more detectors adapted to detect an arrangement of light reflected from the substrate edge; and a controller adapted to determine a polishing endpoint for the substrate edge based on the arrangement of reflected light. Numerous other aspects are provided.

POLISHING ENDPOINT DETECTION SYSTEM AND METHOD USING FRICTION SENSOR

A system method and apparatus to monitor a frictional coefficient of a substrate undergoing polishing is described. A polishing pad assembly includes a polishing layer including a polishing surface, and a substrate contacting member flexibly coupled to the polishing layer having a top surface to contact an exposed surface of a substrate. At least a portion of the top surface is substantially coplanar with the polishing surface. A sensor is provided to measure a lateral displacement of the substrate contacting member. Some embodiments may provide accurate endpoint detection during chemical mechanical polishing to indicate the exposure of an underlying layer. © KIPO & WIPO 2007 ...

Polishing pad with transparent window

A polishing solution is dispensed onto a polishing pad that has a polishing surface, a substrate is brought into contact with the polishing surface, relative motion is created between the substrate and the polishing pad, a light beam is directed through a window in the polishing pad to impinge the substrate, and an intensity of a reflected light beam from the substrate is monitored. The polishing solution has a first refractive index, and the window has a second index of refraction that is approximately equal to the first index of refraction.

GOODNESS OF FIT IN SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING

A sequence of current spectra is obtained with an in-situ optical monitoring system, and each current spectrum is compared to a plurality of reference spectra from a plurality of reference spectra libraries. The library that provides a best fit to the sequence of current spectra is determined, and a polishing endpoint is determined based on the sequence of current spectra and the library that provides a best fit to the sequence of current spectra.

FRICTION SENSOR FOR POLISHING SYSTEM

A system, method and apparatus to monitor a frictional coefficient of a substrate undergoing polishing is described. A polishing pad assembly includes a polishing layer including a polishing surface, and a substrate contacting member flexibly coupled to the polishing layer having a top surface to contact an exposed surface of a substrate. At least a portion of the top surface is substantially coplanar with the polishing surface. A sensor is provided to measure a lateral displacement of the substrate contacting member. Some embodiments may provide accurate endpoint detection during chemical mechanical polishing to indicate the exposure of an underlying layer.

Polishing pad with window having multiple portions

A polishing pad has an opaque polishing layer with an aperture therethrough and a polishing surface, and a solid light-transmissive window in the aperture. The solid light-transmissive window includes an outer portion secured to the polishing layer and an inner portion secured to the outer portion. The outer portion has a upper surface recessed relative to the polishing surface, whereas the inner portion has an upper surface that is substantially co-planar with the polishing surface.

METHODS AND APPARATUS FOR MEASURING SUBSTRATE EDGE THICKNESS DURING POLISHING

Systems, methods and apparatus are provided for determining a substrate polishing endpoint. The invention includes a light source adapted to transmit light to an edge of a substrate; one or more detectors adapted to detect an arrangement of light reflected from the substrate edge; and a controller adapted to determine a polishing endpoint for the substrate edge based on the arrangement of reflected light. Numerous other aspects are provided.

Spectra Based Endpointing for Chemical Mechanical Polishing

A computer implemented method of monitoring a polishing process includes, for each sweep of a plurality of sweeps of an optical sensor across a substrate undergoing polishing, obtaining a plurality of current spectra, each current spectrum of the plurality of current spectra being a spectrum resulting from reflection of white light from the substrate, for each sweep of the plurality of sweeps, determining a difference between each current spectrum and each reference spectrum of a plurality of reference spectra to generate a plurality of differences, for each sweep of the plurality of sweeps, determining a smallest difference of the plurality of differences, thus generating a sequence of smallest difference, and determining a polishing endpoint based on the sequence of smallest differences.

Polishing endpoint detection system and method using friction sensor

A system, method and apparatus to monitor a frictional coefficient of a substrate undergoing polishing is described. A polishing pad assembly includes a polishing layer including a polishing surface, and a substrate contacting member flexibly coupled to the polishing layer having a top surface to contact an exposed surface of a substrate. At least a portion of the top surface is substantially coplanar with the polishing surface. A sensor is provided to measure a lateral displacement of the substrate contacting member. Some embodiments may provide accurate endpoint detection during chemical mechanical polishing to indicate the exposure of an underlying layer.

Endpointing with selective spectral monitoring

A method of controlling polishing includes polishing a substrate, monitoring the substrate during polishing with an in-situ spectrographic monitoring system to generate a sequence of measured spectra, selecting less than all of the measured spectra to generate a sequence of selected spectra, generating a sequence of values from the sequence of selected spectra, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the sequence of values.

High throughput measurement system

A substrate processing system includes a processing module to process a substrate, a factory interface module configured to accommodate at least one cassette for holding the substrate, a spectrographic monitoring system positioned in or adjoining the factory interface module, and a substrate handler to transfer the substrate between the at least one cassette, the spectrographic monitoring system and the processing module.

High Sensitivity Real Time Profile Control Eddy Current Monitoring System

A method of chemical mechanical polishing a metal layer on a substrate includes polishing the metal layer on the substrate at first and second polishing stations, monitoring thickness of the metal layer during polishing at the first and second polishing station with first and second eddy current monitoring systems having different resonant frequencies, and controlling pressures applied by a carrier head to the substrate during polishing at the first and second polishing stations to improve uniformity based on thickness measurements from the first and second eddy current monitoring systems.

Polishing endpoint detection system and method using friction sensor

A system, method and apparatus to monitor a frictional coefficient of a substrate undergoing polishing is described. A polishing pad assembly includes a polishing layer including a polishing surface, and a substrate contacting member flexibly coupled to the polishing layer having a top surface to contact an exposed surface of a substrate. At least a portion of the top surface is substantially coplanar with the polishing surface. A sensor is provided to measure a lateral displacement of the substrate contacting member. Some embodiments may provide accurate endpoint detection during chemical mechanical polishing to indicate the exposure of an underlying layer.

Signal improvement in eddy current sensing

Improved endpoint detection and/or thickness measurements may be obtained by correcting sensor data using calibration parameters and/or drift compensation parameters. Calibration parameters may include an offset and a slope, or other parameters. Drift compensation parameters may include off-wafer measurements.

Thin polishing pad with window and molding process

A polishing pad is described that has a polishing layer with a polishing surface, an adhesive layer on a side of the polishing layer opposite the polishing layer, and a solid light-transmitting window extending through and molded to the polishing layer. The window has a top surface coplanar with the polishing surface and a bottom surface coplanar with a lower surface of the adhesive layer. A method of making a polishing pad includes forming an aperture through a polishing layer and an adhesive layer, securing a backing piece to the adhesive layer on a side opposite a polishing surface of the polishing layer, dispensing a liquid polymer into the aperture, and curing the liquid polymer to form a window.

Integrated endpoint detection system with optical and eddy current monitoring

A chemical mechanical polishing apparatus and method can use an eddy current monitoring system and an optical monitoring system. Signals from the monitoring systems can be combined on an output line and extracted by a computer. A thickness of a polishing pad can be calculated. The eddy current monitoring system and optical monitoring system can measure substantially the same location on the substrate.

TREATMENT OF POLISHING PAD WINDOW

A window of solid light-transmissive polymer is formed in a polishing pad, and at least one surface of the window is treated to increase the smoothness of the at least one surface.

User-input functions for data sequences in polishing endpoint detection

A method of controlling polishing includes receiving user input through a graphical user interface selecting a function, the function including at least one parameter that can be varied, polishing a substrate, monitoring a substrate during polishing with an in-situ monitoring system, generating a sequence of values from measurements from the in-situ monitoring system, fitting the function to the sequence of values, the fitting including determining a value of the at least one parameter that provides a best fit of the function to the sequence of values, determining a projected time at which the function equals a target value, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the projected time.

Substrate thickness measuring during polishing

A computer program product that determines a polishing endpoint includes obtaining spectra from different zones on a substrate during different times in a polishing sequence, matches the spectra with indexes in a library and uses the indexes to determining a polishing rate for each of the different zones from the indexes. An adjusted polishing rate can be determined for one of the zones, which causes the substrate to have a desired profile when the polishing end time is reached.

Selecting Reference Libraries For Monitoring Of Multiple Zones On A Substrate

A method of configuring a polishing monitoring system includes receiving user input selecting a plurality of libraries, each library of the plurality of libraries comprising a plurality of reference spectra for use in matching to measured spectra during polishing, each reference spectrum of the plurality of reference spectra having an associated index value, for a first zone of a substrate, receiving user input selecting a first subset of the plurality of libraries, and for a second zone of the substrate, receiving user input selecting a second subset of the plurality of libraries. 1. A method of configuring a polishing monitoring system , comprising:receiving user input selecting a plurality of libraries, each library of the plurality of libraries comprising a plurality of reference spectra for use in matching to measured spectra during polishing, each reference spectrum of the plurality of reference spectra having an associated index value;for a first zone of a substrate, receiving user input selecting a first subset of the plurality of libraries; andfor a second zone of the substrate, receiving user input selecting a second subset of the plurality of libraries.2. The method of claim 1 , further comprising:polishing the substrate in a polishing apparatus;measuring a first sequence of spectra from the first zone of the substrate during polishing with an in-situ monitoring system;for each measured spectrum in the first sequence of spectra from the first zone, for each library from the first subset of the plurality of libraries, determining a best matching reference spectrum; andfor each library from the first subset of libraries for each best matching reference spectrum for the first zone of the substrate, determining a first index value to generate a first sequence of first index values for each library from the first subset of libraries.3. The method of claim 2 , further comprising:measuring a second sequence of spectra from the second zone of the substrate during ...

Gathering Spectra From Multiple Optical Heads

A polishing apparatus includes a platen to hold a polishing pad having a plurality of optical apertures, a carrier head to hold a substrate against the polishing pad, a motor to generate relative motion between the carrier head and the platen, and an optical monitoring system. The optical monitoring system includes at least one light source, a common detector, and an optical assembly configured to direct light from the at least one light source to each of a plurality of separated positions in the platen, to direct light from each position of the plurality of separated positions to the substrate as the substrate passes over said each position, to receive reflected light from the substrate as the substrate passes over said each position, and to direct the reflected light from each of the plurality of separated positions to the common detector. 1. A polishing apparatus , comprising:a platen to hold a polishing pad having a plurality of optical apertures;a carrier head to hold a substrate against the polishing pad;a motor to generate relative motion between the carrier head and the platen; and at least one light source,', 'a common detector, and', 'an optical assembly configured to direct light from the at least one light source to each of a plurality of separated positions in the platen, to direct light from each position of the plurality of separated positions to the substrate as the substrate passes over said each position, to receive reflected light from the substrate as the substrate passes over said each position, and to direct the reflected light from each of the plurality of separated positions to the common detector., 'an optical monitoring system, the optical monitoring system including'}2. The polishing apparatus of claim 1 , wherein the platen is rotatable about an axis of rotation.3. The polishing apparatus of claim 2 , wherein the plurality of separated positions are spaced equidistant from the axis of rotation.4. The polishing apparatus of claim 2 , ...

AUTOMATIC SELECTION OF REFERENCE SPECTRA LIBRARY

A computer-implemented method of generating reference spectra includes polishing a plurality of set-up substrates, the plurality of set-up substrates comprising at least three set-up substrates, measuring a sequence of spectra from each of the plurality of set-up substrates during polishing with an in-situ optical monitoring system to provide a plurality of sequences of spectra, generating a plurality of sequences of potential reference spectra from the plurality of sequences of spectra, determining which sequence of potential reference spectra of the plurality of sequences provides a best match to remaining sequences of the plurality of sequences, and storing the sequence of potential reference spectra determined to provide the best match as reference spectra, and selecting and storing the sequence of potential reference spectra. 1. A computer-implemented method of generating reference spectra , comprising:polishing a plurality of set-up substrates, the plurality of set-up substrates comprising at least three set-up substrates;measuring a sequence of spectra from each of the plurality of set-up substrates during polishing with an in-situ optical monitoring system to provide a plurality of sequences of spectra;generating a plurality of sequences of potential reference spectra from the plurality of sequences of spectra;determining which sequence of potential reference spectra of the plurality of sequences provides a best match to remaining sequences of the plurality of sequences; andselecting and storing the sequence of potential reference spectra determined to provide the best match as reference spectra.2. The method of claim 1 , wherein generating the plurality of sequences of potential reference spectra comprises generating a sequence of potential reference spectra from each sequence of spectra.3. The method of claim 2 , wherein measuring the sequence of spectra comprises claim 2 , at each time interval of a plurality of regular time intervals claim 2 , collecting ...

EDDY CURRENT MONITORING OF METAL RESIDUE OR METAL PILLARS

A method of chemical mechanical polishing a substrate includes polishing a metal layer on the substrate at a polishing station, monitoring thickness of the metal layer during polishing at the polishing station with an eddy current monitoring system, and halting polishing when the eddy current monitoring system indicates that residue of the metal layer is removed from an underlying layer and a top surface of the underlying layer is exposed. 1. A method of chemical mechanical polishing a substrate , comprising:polishing a metal layer on the substrate at a polishing station;monitoring thickness of the metal layer during polishing at the polishing station with an eddy current monitoring system; andhalting polishing when the eddy current monitoring system indicates that residue of the metal layer is removed from an underlying layer and a top surface of the underlying layer is exposed.2. The method of claim 1 , wherein the underlying layer is a barrier layer.3. The method of claim 1 , wherein the underlying layer is a dielectric layer.4. The method of claim 1 , wherein the eddy current monitoring system has a resonant frequency greater than 12 MHz.5. The method of claim 3 , wherein the eddy current monitoring system has a resonant frequency between about 14 and 16 MHz.6. The method of claim 1 , wherein metal of the metal layer has a resistivity less than 700 ohm-Angstroms.7. The method of claim 5 , wherein the metal is copper claim 5 , aluminum or tungsten.8. The method of claim 1 , further comprising monitoring polishing of the metal layer without an optical monitoring system.9. The method of claim 5 , further comprising determining that residue of the metal layer is removed by detecting a change in the rate of change in magnitude of a signal from the eddy current monitoring system.10. A method of chemical mechanical polishing a substrate claim 5 , comprising:polishing a plurality of metal pillars on the substrate, the pillars projecting upwardly from a generally planar ...

SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING USING INDEX VALUES

Methods, systems, and apparatus for spectrographic monitoring of a substrate during chemical mechanical polishing are described. In one aspect, a computer-implemented method includes storing a library having a plurality of reference spectra, each reference spectrum of the plurality of reference spectra having a stored associated index value, measuring a sequence of spectra in-situ during polishing to obtain measured spectra, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum to generate a sequence of best matching reference spectra, determining the associated index value for each best matching spectrum from the sequence of best matching reference spectra to generate a sequence of index values, fitting a linear function to the sequence of index values, and halting the polishing either when the linear function matches or exceeds a target index or when the associated index value from the determining step matches or exceeds the target index. 1. A method of controlling a chemical mechanical polishing operation , comprising:polishing a substrate;storing a library having a plurality of reference spectra, each reference spectrum of the plurality of reference spectra having a stored associated value, each stored associated value representing a time during a polishing operation at which the reference spectrum of the plurality of reference spectra with the associated value is expected to be observed, wherein each stored associated value was generated prior to polishing of the substrate;measuring a sequence of spectra in-situ during polishing to obtain measured spectra;for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum from the plurality of reference spectra to generate a sequence of best matching reference spectra;determining the stored associated value for each best matching spectrum from the sequence of best matching reference spectra to generate a sequence of values;fitting a ...

Semi-Quantitative Thickness Determination

While a substrate is polished, it is also irradiated with light from a light source. A current spectrum of the light reflected from the surface of the substrate is measured. A selected peak, having a first parameter value, is identified in the current spectrum. A value of a second parameter associated with the first parameter is determined from a lookup table using a processor. Depending on the value of the second parameter, the polishing of the substrate is changed. An initial spectrum of light reflected from the substrate before the polishing of the substrate can be measured and a wavelength corresponding to a selected peak of the initial spectrum can be determined. 1. A method of performing polishing , comprising:measuring an initial spectrum of light reflected from a substrate;identifying a selected extrema in the initial spectrum and determining an initial wavelength or an initial width of the selected extrema in the initial spectrum;polishing the substrate with a polishing pad; irradiating the substrate with light from a light source to generate light reflected from the substrate,', 'measuring, using a processor, a current spectrum of the light reflected from the substrate,', 'identifying, using the processor, the selected extrema in the current spectrum and determining a current wavelength or a current width of the selected extrema in the current spectrum,', 'determining, using the processor, a difference between the initial wavelength or initial width and the current wavelength or current width, respectively; and, 'while the substrate is being polished and after measuring the initial spectrum,'}changing, using a controller, the polishing of the substrate depending upon the difference.2. The method of claim 1 , wherein the selected extrema comprises a peak.3. The method of claim 1 , wherein the difference is a wavelength shift relative to the initial wavelength.4. The method of claim 1 , wherein the difference is a change of width relative to the initial ...

FRICTION SENSOR FOR POLISHING SYSTEM

A system method and apparatus to monitor a frictional coefficient of a substrate undergoing polishing is described. A polishing pad assembly includes a polishing layer including a polishing surface, and a substrate contacting member flexibly coupled to the polishing layer having a top surface to contact an exposed surface of a substrate. At least a portion of the top surface is substantially coplanar with the polishing surface. A sensor is provided to measure a lateral displacement of the substrate contacting member. Some embodiments may provide accurate endpoint detection during chemical mechanical polishing to indicate the exposure of an underlying layer. 1. An apparatus to monitor a frictional coefficient of a substrate undergoing polishing , comprising:a support to hold a polishing article with a polishing surface;a carrier to hold an outer surface of the substrate against the polishing surface;a member laterally movable relative to the support and having a top surface to contact the outer surface of the substrate as the substrate is held by the carrier with the exposed surface against the polishing surface;a first restorative material configured to apply a first force on the member in a direction parallel to the polishing surface to urge the member toward a neutral lateral position relative to the support;a first restorative material configured to apply a second force on the member in a direction perpendicular to the polishing surface to urge the member toward the outer surface; anda sensor to generate a signal based on a lateral displacement of the movable member.2. The apparatus of claim 1 , wherein and the first restorative material connects the second restorative material to the support the second restorative material connects the first restorative material to the member.3. The apparatus of claim 1 , wherein the first restorative material includes a first leaf spring and the second restorative material includes a second leaf spring.4. The apparatus of claim ...

Adjusting Polishing Rates by Using Spectrographic Monitoring of a Substrate During Processing

A computer-implemented method includes receiving a sequence of current spectra of reflected light from a substrate; comparing each current spectrum from the sequence of current spectra to a plurality of reference spectra from a reference spectra library to generate a sequence of best-match reference spectra; determining a goodness of fit for the sequence of best-match reference spectra; and determining at least one of whether to adjust a polishing rate or an adjustment for the polishing rate, based on the goodness of fit.

Feedback Control Using Detection Of Clearance And Adjustment For Uniform Topography

A method of controlling polishing includes storing a desired ratio representing a ratio for a clearance time of a first zone of a substrate to a clearance time of a second zone of the substrate. During polishing of a first substrate, an overlying layer is monitored, a sequence of measurements is generated, and the measurements are sorted a first group associated with the first zone of the substrate and a second group associated with the second zone on the substrate. A first time and a second time at which the overlying layer is cleared is determined based on the measurements from the first group and the second group, respectively. At least one adjusted polishing pressure is calculated for the first zone based on a first pressure applied in the first zone during polishing the first substrate, the first time, the second time, and the desired ratio. 1. A method of controlling polishing , comprising:storing a desired ratio, the desired ratio representing a ratio for a clearance time of a first zone of a substrate to a clearance time of a second zone of the substrate;polishing a first substrate having an overlying layer on an underlying layer or layer structure;during polishing, monitoring the overlying layer with an in-situ monitoring system and generating a sequence of measurements from the in-situ monitoring system;sorting the measurements into a first group associated with the first zone of the substrate and a second group associated with the second zone on the substrate;determining a first time at which the overlying layer is cleared based on the measurements from the first group;determining a second time at which the overlying layer is cleared from the second zone on the substrate based on the measurements from the second group;calculating at least one adjusted polishing pressure for the first zone based on a first pressure applied in the first zone during polishing the first substrate, the first time, the second time, and the desired ratio; andpolishing a second ...

POLISHING PAD WITH TWO-SECTION WINDOW HAVING RECESS

A method of forming a polishing pad with a polishing layer having a polishing surface and a back surface. A plurality of grooves are formed on the polishing surface, and an indentation is formed in the back surface of the polishing layer. A region on the polishing surface corresponding to the indentation in the back surface is free of grooves or has shallower grooves.

METHOD OF CONTROLLING POLISHING USING IN-SITU OPTICAL MONITORING AND FOURIER TRANSFORM

A method of controlling a polishing operation includes polishing a substrate, during polishing obtaining a sequence over time of measured spectra from the substrate with an in-situ optical monitoring system, for each measured spectrum from the sequence of measured spectra applying a Fourier transform to the measured spectrum to generate a transformed spectrum thus generating a sequence of transformed spectra, for each transformed spectrum identifying a peak of interest from a plurality of peaks in the transformed spectrum, for each transformed spectrum determining a position value for the peak of interest in the transformed spectrum thus generating a sequence of position values, and determining at least one of a polishing endpoint or an adjustment of a pressure to the substrate from the sequence of position values. 1. A method of controlling a polishing operation , comprising:polishing a substrate;during polishing, obtaining a sequence over time of measured spectra from the substrate with an in-situ optical monitoring system;for each measured spectrum from the sequence of measured spectra, applying a Fourier transform to the measured spectrum to generate a transformed spectrum thus generating a sequence of transformed spectra;for each transformed spectrum, selecting a peak of interest from a plurality of peaks in the transformed spectrum, wherein selecting the peak of interest includes identifying a highest peak and a second-highest peak within a range of position values, determining a height and a position for each of the highest peak and a second-highest peak, and determining whether the highest peak is has a lower position value than the second-highest peak;for each transformed spectrum, determining a position value for the peak of interest in the transformed spectrum thus generating a sequence of position values; anddetermining at least one of a polishing endpoint or an adjustment of a pressure to the substrate from the sequence of position values.2. The method ...

USER-INPUT FUNCTIONS FOR DATA SEQUENCES IN POLISHING ENDPOINT DETECTION

A method of controlling polishing includes receiving user input through a graphical user interface selecting a function, the function including at least one parameter that can be varied, polishing a substrate, monitoring a substrate during polishing with an in-situ monitoring system, generating a sequence of values from measurements from the in-situ monitoring system, fitting the function to the sequence of values, the fitting including determining a value of the at least one parameter that provides a best fit of the function to the sequence of values, determining a projected time at which the function equals a target value, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the projected time. 1. A method of controlling polishing , comprising:receiving user input through a graphical user interface selecting a function, the function including at least one parameter that can be varied;polishing a substrate;monitoring a substrate during polishing with an in-situ monitoring system;generating a sequence of values from measurements from the in-situ monitoring system;fitting the function to the sequence of values, the fitting including determining a value of the at least one parameter that provides a best fit of the function to the sequence of values;determining a projected time at which the function equals a target value; anddetermining at least one of a polishing endpoint or an adjustment for a polishing rate based on the projected time.2. The method of claim 1 , wherein receiving user input comprises receiving user input selecting at least one constant in the function.3. The method of claim 1 , comprising converting textual input to a mathematical function.4. The method of claim 1 , wherein receiving user input comprises receiving a user selection from a predetermined set of discrete mathematical functions.5. The method of claim 4 , wherein receiving user input comprises receiving a plurality of user selections from the ...

POLISHING PAD FOR ENDPOINT DETECTION AND RELATED METHODS

A polishing pad has a polishing layer with a polishing surface and a back surface. A plurality of grooves are formed on the polishing surface, and an indentation is formed in the back surface of the polishing layer. A region on the polishing surface corresponding to the indentation in the back surface is free of grooves or has shallower grooves. 139-. (canceled)40. A polishing pad , comprising:a polishing piece having a polishing surface, a bottom surface, and an aperture extending from the polishing surface to the bottom surface, the polishing piece including a polishing layer having the polishing surface, the polishing piece having a plurality of grooves formed in the polishing surface, the grooves extending partially but not entirely through the polishing layer; anda solid light-transmissive window situated in the aperture and secured to the polishing piece, the window having a lower surface and an upper surface, the upper surface substantially coplanar with the polishing surface and lacking grooves, the lower surface having an indentation that extends partially but not entirely through the window, wherein the indentation is empty, and wherein the window is configured such that the upper surface is substantially fixed relative to the polishing surface.41. The polishing pad of claim 40 , wherein the polishing piece includes a backing layer having the bottom surface.42. The polishing pad of claim 41 , wherein the backing layer is softer than the polishing layer.43. The polishing pad of claim 41 , wherein the backing layer is non-compressible.44. The polishing pad of claim 41 , wherein the aperture includes a first section through the polishing layer and a second section through the backing layer claim 41 , and wherein the first section is wider than the second section.45. The polishing pad of claim 45 , wherein a portion of the bottom surface at the periphery of the window rests on a portion of the backing layer surrounding the second section of the aperture.46. ...

THIN POLISHING PAD WITH WINDOW AND MOLDING PROCESS

A polishing pad is described that has a polishing layer with a polishing surface, an adhesive layer on a side of the polishing layer opposite the polishing layer, and a solid light-transmitting window extending through and molded to the polishing layer. The window has a top surface coplanar with the polishing surface and a bottom surface coplanar with a lower surface of the adhesive layer. A method of making a polishing pad includes forming an aperture through a polishing layer and an adhesive layer, securing a backing piece to the adhesive layer on a side opposite a polishing surface of the polishing layer, dispensing a liquid polymer into the aperture, and curing the liquid polymer to form a window. 120-. (canceled)21. A polishing pad , comprising:a polishing layer having a polishing surface, an aperture extending entirely through the polishing layer, and a plurality of grooves that intersect the aperture and that extend partially but not entirely through the polishing layer; anda solid light-transmitting window filling the aperture and molded to the polishing layer, the window having a top surface coplanar with the polishing surface, and wherein a portion of the window projects laterally past edges of the aperture into the grooves and is molded to the grooves.22. The polishing pad of claim 21 , wherein the polishing layer consists of a single layer.23. The polishing pad of claim 22 , wherein the grooves are about half the depth of the polishing pad.24. The polishing pad of claim 21 , wherein the polishing pad has a total thickness less than 1 mm.25. The polishing pad of claim 21 , wherein the grooves form a cross-hatched pattern.26. The polishing pad of claim 21 , wherein the grooves have sloped side walls.27. The polishing pad of claim 21 , wherein the window has a top surface coplanar with the polishing surface.28. The polishing pad of claim 21 , wherein the window comprises a plurality of projections that extend past an edge of the aperture into the grooves.29 ...

Endpointing detection for chemical mechanical polishing based on spectrometry

Methods and apparatus for spectrum-based endpointing. An endpointing method includes selecting a reference spectrum. The reference spectrum is a spectrum of white light reflected from a film of interest on a first substrate and has a thickness greater than a target thickness. The reference spectrum is empirically selected for particular spectrum-based endpoint determination logic so that the target thickness is achieved when endpoint is called by applying the particular spectrum-based endpoint logic. The method includes obtaining a current spectrum. The current spectrum is a spectrum of white light reflected from a film of interest on a second substrate when the film of interest is being subjected to a polishing step and has a current thickness that is greater than the target thickness. The method includes determining, for the second substrate, when an endpoint of the polishing step has been achieved. The determining is based on the reference and current spectra.

Gathering Spectra From Multiple Optical Heads

A polishing apparatus includes a platen to hold a polishing pad having a plurality of optical apertures, a carrier head to hold a substrate against the polishing pad, a motor to generate relative motion between the carrier head and the platen, and an optical monitoring system. The optical monitoring system includes at least one light source, a common detector, and an optical assembly configured to direct light from the at least one light source to each of a plurality of separated positions in the platen, to direct light from each position of the plurality of separated positions to the substrate as the substrate passes over said each position, to receive reflected light from the substrate as the substrate passes over said each position, and to direct the reflected light from each of the plurality of separated positions to the common detector. 1. A polishing apparatus , comprising:a platen to hold a polishing pad having a plurality of optical apertures;a carrier head to hold a substrate against the polishing pad;a motor to generate relative motion between the carrier head and the platen; and at least one light source,', 'a common detector, and', 'an optical assembly configured to direct light from the at least one light source to each of a plurality of separated positions in the platen, to direct light from each position of the plurality of separated positions to the substrate as the substrate passes over said each position, to receive reflected light from the substrate as the substrate passes over said each position, and to direct the reflected light from each of the plurality of separated positions to the common detector., 'an optical monitoring system, the optical monitoring system including'}2. The polishing apparatus of claim 1 , wherein the platen is rotatable about an axis of rotation.3. The polishing apparatus of claim 2 , wherein the plurality of separated positions are spaced equidistant from the axis of rotation.4. The polishing apparatus of claim 2 , ...

SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING USING INDEX VALUES

Methods, systems, and apparatus for spectrographic monitoring of a substrate during chemical mechanical polishing are described. In one aspect, a computer-implemented method includes storing a library having a plurality of reference spectra, each reference spectrum of the plurality of reference spectra having a stored associated index value, measuring a sequence of spectra in-situ during polishing to obtain measured spectra, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum to generate a sequence of best matching reference spectra, determining the associated index value for each best matching spectrum from the sequence of best matching reference spectra to generate a sequence of index values, fitting a linear function to the sequence of index values, and halting the polishing either when the linear function matches or exceeds a target index or when the associated index value from the determining step matches or exceeds the target index. 110-. (canceled)11. A method of controlling a chemical mechanical polishing operation , comprising:polishing a substrate, wherein polishing the substrate comprises rotating a platen;storing a library having a plurality of reference spectra, each reference spectrum of the plurality of reference spectra having a stored associated value, and wherein each stored associated value is a number of rotations of the platen at which the reference spectrum with the stored associated value is expected to be observed;measuring a sequence of spectra in-situ during polishing to obtain measured spectra;for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum from the plurality of reference spectra to generate a sequence of best matching reference spectra;determining the stored associated value for each best matching spectrum from the sequence of best matching reference spectra to generate a sequence of values;fitting a function to the sequence of values; andat ...

Using Spectra to Determine Polishing Endpoints

Methods of determining a polishing endpoint are described using spectra obtained during a polishing sequence. In particular, techniques for using only desired spectra, faster searching methods and more robust rate determination methods are described. 120-. (canceled)21. A method for determining outlier spectra , comprising:while polishing a substrate, obtaining at least three spectra from a surface of the substrate during a scan of an optical monitoring module across the substrate;determining a difference between each of the at least three spectra, wherein determining a difference comprises calculating for each spectrum of the at least three spectra a cumulative sum of differences between the each spectrum and all other spectra of the at least three spectra;selecting an outlier spectrum from the at least three spectra based on the difference; anddiscarding the outlier spectrum.22. The method of claim 21 , wherein calculating the cumulative sum for each spectrum of the at least three spectra comprises calculating a cumulative sum of squares difference between the each spectrum and other spectra of the at least three spectra.23. The method of claim 21 , wherein calculating a cumulative sum of differences for each spectrum of the at least three spectra generates a plurality of cumulative sums claim 21 , and determining the difference comprises selecting a lowest cumulative sum of the plurality of cumulative sums and dividing each cumulative sum by the lowest cumulative sum to obtain a normalized number for each spectrum.24. The method of claim 23 , wherein selecting the outlier spectrum comprises selecting the spectrum having a normalized number over a predetermined threshold.25. The method of claim 21 , wherein the scan of the optical monitoring module across the substrate corresponds to a single rotation of a platen supporting the optical monitoring module.26. A method of determining an endpoint claim 21 , comprising:while polishing a substrate, obtaining at least ...

POLISHING PAD WITH TWO-SECTION WINDOW HAVING RECESS

A method of forming a polishing pad with a polishing layer having a polishing surface and a back surface. A plurality of grooves are formed on the polishing surface, and an indentation is formed in the back surface of the polishing layer. A region on the polishing surface corresponding to the indentation in the back surface is free of grooves or has shallower grooves. 139-. (canceled)40. A polishing pad , comprising:a polishing article having a polishing surface and a bottom surface, an aperture formed through the polishing article from the polishing surface to the bottom surface, the aperture having a first portion adjacent the polishing surface with a first cross-sectional width and a second portion adjacent the bottom surface with a second cross-sectional width greater than the first cross-sectional width such that a projecting section of the polishing article extends over the second portion of the aperture; anda transparent body secured in the aperture, the transparent body including a first section positioned in the first portion of the aperture and a second section positioned in the second portion of the aperture, an upper surface of the second section adhesively secured to a lower surface of the projecting section, the transparent body including a recess formed in an underside of the second section, the recess having a cross-sectional width less than the first cross-sectional width of the first portion of the aperture, the recess extending upwardly from the underside of the second section past the upper surface of the second section and into the first section, an entirety of a region of the first section extending from the upper surface of the second section to a ceiling of the recess having straight vertical side walls.41. The polishing pad of claim 40 , wherein the top surface of the first section of the transparent body is substantially coplanar with the polishing surface.42. The polishing pad of claim 40 , wherein the second section of the transparent ...

In-Situ Acoustic Monitoring of Chemical Mechanical Polishing

A method of controlling chemical mechanical polishing includes polishing a substrate having a plurality of protrusions, monitoring the substrate during polishing with an in-situ monitoring system to generate a signal, the in-situ monitoring system including an acoustic sensor, a motor current sensor or a motor torque sensor, and detecting breakage of the protrusions based on the signal. 1. A method of controlling chemical mechanical polishing , comprising:polishing a substrate having a plurality of protrusions;during polishing, monitoring the substrate with an in-situ monitoring system to generate a signal, the in-situ monitoring system including an acoustic sensor, a motor current sensor or a motor torque sensor;detecting breakage of the protrusions based on the signal.2. The method of claim 1 , wherein detecting breakage comprises comparing a signal intensity to a threshold value.3. The method of claim 2 , comprising calculating the signal intensity from a root mean square of the signal4. The method of claim 2 , comprising performing a Fast Fourier Transform on the signal to generate a transformed signal claim 2 , and calculating the signal intensity based on an intensity of a frequency band of the transformed signal.5. The method of claim 2 , comprising performing a wavelet packet transform on the signal to generate a plurality of signal components claim 2 , and calculating the signal intensity based on an intensity of a signal component.6. The method of claim 1 , comprising halting polishing upon detecting breakage of the protrusions.7. The method of claim 1 , wherein detecting breakage of the protrusions triggers reducing a pressure and/or a relative speed of polishing for a subsequent substrate.8. The method of claim 1 , wherein the protrusions comprise stubs of through silicon vias in the substrate.9. A chemical mechanical polishing apparatus claim 1 , comprising:a platen to support a polishing pad;a carrier head to hold a substrate in contact with the ...

RESISTIVITY-BASED ADJUSTMENT OF THRESHOLDS FOR IN-SITU MONITORING

A first resistivity value and a correlation function relating thickness of a conductive layer having the first resistivity value to a signal from an in-situ monitoring system are stored. A second resistivity value for a conductive layer on a substrate is received. A sequence of signal values that depend on thickness of the conductive layer is received from an in-situ electromagnetic induction monitoring system that monitors the substrate during polishing. A sequence of thickness values is generated based on the sequence of signal values and the correlation function. For at least some thickness values of the sequence of thickness values adjusted thickness values are generated that compensate for variation between the first resistivity value and the second resistivity value to generate a sequence of adjusted thickness values. A polishing endpoint is detected or an adjustment for a polishing parameter is determined based on the sequence of adjusted thickness values. 1. A computer program product , tangibly encoded on a non-transitory computer readable media , comprising instructions to cause a computer system to:store a first resistivity value and a correlation function relating layer thickness of a conductive material having the first resistivity value at a temperature to a signal from an in-situ monitoring system, the first resistivity value generated from a textbook value or a measurement of a calibration substrate;receive a second resistivity value for a deposited conductive layer of the conductive material at the temperature generated by a measurement of the deposited conductive layer on a device substrate to be polished;receive a sequence of signal values that depend on thickness of the deposited conductive layer from an in-situ electromagnetic induction monitoring system that monitors the device substrate during polishing;generate a sequence of thickness values based on the sequence of signal values and the correlation function;calculate a threshold signal value ...

ENDPOINTING WITH SELECTIVE SPECTRAL MONITORING

A method of controlling polishing includes polishing a substrate, monitoring the substrate during polishing with an in-situ spectrographic monitoring system to generate a sequence of measured spectra, selecting less than all of the measured spectra to generate a sequence of selected spectra, generating a sequence of values from the sequence of selected spectra, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the sequence of values. 1. A method of controlling polishing , comprising:polishing a substrate;monitoring the substrate during polishing with an in-situ spectrographic monitoring system to generate a sequence of measured spectra;selecting less than all of the measured spectra to generate a sequence of selected spectra;generating a sequence of values from the sequence of selected spectra; anddetermining at least one of a polishing endpoint or an adjustment for a polishing rate based on the sequence of values.2. The method of claim 1 , wherein selecting less than all of the measured spectra comprises comparing each measured spectrum from the sequence of measured spectra to a baseline spectrum.3. The method of claim 2 , wherein the baseline spectrum is determined empirically claim 2 , calculated from an optical model claim 2 , or taken from literature.4. The method of claim 3 , wherein the baseline spectrum is determined empirically using a spectrographic metrology system that generates a measurements spot smaller than a measurement spot generated by the in-situ monitoring system.5. The method of claim 2 , wherein comparing includes calculating a sum-of-squares difference claim 2 , a sum of absolute differences claim 2 , or a cross-correlation between each measured spectrum and the baseline spectrum.6. The method of claim 1 , wherein selecting less than all of the measured spectra comprises determining the presence or absence of a feature in the measured spectrum.7. The method of claim 6 , wherein the feature ...

INDUCTIVE MONITORING OF CONDUCTIVE LOOPS

In fabrication of an integrated circuit having a layer with a plurality of conductive interconnects, a layer of a substrate is polished to provide the layer of the integrated circuit. The layer of the substrate includes conductive lines to provide the conductive interconnects. The layer of the substrate includes a closed conductive loop formed of a conductive material in a trench. A depth of the conductive material in the trench is monitored using an inductive monitoring system and a signal is generated. Monitoring includes generating a magnetic field that intermittently passes through the closed conductive loop. A sequence of values over time is extracted from the signal, the sequence of values representing the depth of the conductive material over time. 1. A method of chemical mechanical polishing a substrate , comprising:polishing a substrate to provide a layer of an integrated circuit with a plurality of conductive interconnects, wherein the layer includes conductive lines to provide the conductive interconnects and a plurality of closed conductive loops formed of a conductive material in trenches;during polishing, sweeping a sensor of an in-situ inductive monitoring system across the substrate to generate a signal, the sensor generating a magnetic field that at least intermittently impinges the substrate;for each sweep of the sensor, determining portions of the signal that correspond to the sensor aligning with and the magnetic field passing through at least some of the plurality of closed conductive loops; andat least one of halting polishing or adjusting at least one pressure applied by a carrier head to the substrate based on the portions of the signal.2. The method of claim 1 , generating a sequence of values representing a depth over time of the conductive material in the trenches based on the portions of the signal.3. The method of claim 2 , wherein generating the sequence of values includes identifying one or more peaks in the signal and determining a ...

IN-SITU MONITORING SYSTEM WITH MONITORING OF ELONGATED REGION

A method of chemical mechanical polishing a substrate includes polishing a layer on the substrate at a polishing station, monitoring the layer during polishing at the polishing station with an in-situ monitoring system, the in-situ monitoring system monitoring an elongated region and generating a measured signal, computing an angle between a primary axis of the elongated region and a tangent to an edge of the substrate, modifying the measured signal based on the angle to generate a modified signal, and at least one of detecting a polishing endpoint or modifying a polishing parameter based on the modified signal. 1. A method of chemical mechanical polishing a substrate , comprising:polishing a layer on the substrate at a polishing station;monitoring the layer during polishing at the polishing station with an in-situ monitoring system, the in-situ monitoring system monitoring an elongated region and generating a measured signal;computing an angle between a primary axis of the elongated region and a tangent to an edge of the substrate;modifying the measured signal based on the angle to generate a modified signal; andat least one of detecting a polishing endpoint or modifying a polishing parameter based on the modified signal.2. The method of claim 1 , wherein the angle comprises the angle at a time when the elongated region is adjacent the edge of the substrate.3. The method of claim 2 , comprising detecting edge portions of the signal.4. The method of claim 3 , wherein modifying the measured signal comprises compressing or decompressing the edge portions.5. The method of claim 4 , wherein a compression ratio from the compressing or decompressing is a function of the angle.6. The method of claim 5 , wherein the function of the angle is such that the compression ratio increases as the angle increases.7. The method of claim 2 , wherein modifying the measured signal comprises multiplying the signal by a gain factor.8. The method of claim 7 , wherein the gain factor is a ...

ENDPOINT DETECTION FOR CHEMICAL MECHANICAL POLISHING BASED ON SPECTROMETRY

A method of detecting a polishing endpoint includes storing a plurality of library spectra, measuring a sequence of spectra from the substrate in-situ during polishing, and for each measured spectrum of the sequence of spectra, finding a best matching library spectrum from the plurality of library spectra to generate a sequence of best matching library spectra. Each library spectrum has a stored associated value representing a degree of progress through a polishing process, and the stored associated value for the best matching library spectrum is determined for each best matching library spectrum to generate a sequence of values representing a progression of polishing of the substrate. The sequence of values is compared to a target value, and a polishing endpoint is triggered when the sequence of values reaches the target value. 120-. (canceled)21. A method of controlling a chemical mechanical polishing operation , comprising:storing a plurality of library spectra, each library spectrum of the plurality of library spectra having a stored associated value representing a degree of progress through a polishing process;polishing a substrate;measuring a sequence of spectra from the substrate in-situ during polishing;for each measured spectrum of the sequence of spectra, finding a best matching library spectrum from the plurality of library spectra to generate a sequence of best matching library spectra;for each best matching library spectrum from the sequence of best matching library spectra, determining the stored associated value for the best matching library spectrum to generate a sequence of values representing a progression of polishing of the substrate;comparing the sequence of values to a target value; andtriggering a polishing endpoint when the sequence of values reaches the target value.22. The method of claim 21 , wherein each library spectrum of the plurality of library spectra has a unique associated value.23. The method of claim 21 , further comprising ...

Multi-Platen Multi-Head Polishing Architecture

A polishing apparatus includes a plurality of stations supported on a platform, the plurality of stations including at least two polishing stations and a transfer station, each polishing station including a platen to support a polishing pad, a plurality of carrier heads suspended from and movable along a track such that each polishing station is selectively positionable at the stations, and a controller configured to control motion of the carrier heads along the track such that during polishing at each polishing station only a single carrier head is positioned in the polishing station.

Polishing System with In-Sequence Sensor

A polishing apparatus includes a plurality of stations supported on a platform, the plurality of stations including at least two polishing stations and a transfer station, each polishing station including a platen to support a polishing pad, a plurality of carrier heads suspended from and movable along a track such that each polishing station is selectively positionable at the stations, and a controller configured to control motion of the carrier heads along the track such that during polishing at each polishing station only a single carrier head is positioned in the polishing station. 1. A polishing apparatus comprising:five stations supported on a platform and positioned at substantially equal angular intervals around a center of the platform, the five stations including three polishing stations, a transfer station and a metrology station, each polishing station including a platen to support a polishing pad;a plurality of carrier heads suspended from and movable along a track such that each polishing station is selectively positionable at the stations; andan in-sequence metrology system having a probe located in the metrology station.2. The polishing apparatus of claim 1 , wherein the metrology station includes a single probe from the in-sequence metrology system.3. The polishing apparatus of claim 1 , wherein the metrology station includes a plurality of probes from a plurality of in-sequence metrology systems.4. The polishing apparatus of claim 1 , wherein the metrology station is positioned between two of the three polishing stations.5. The polishing apparatus of claim 1 , wherein the metrology station is positioned between the transfer station and a polishing station of the three polishing stations.6. The polishing apparatus of claim 1 , wherein the track is circular.7. A polishing apparatus comprising:a plurality of polishing stations, each polishing station including a platen to support a polishing pad;a plurality of carrier heads held by a support structure ...

APPLYING DIMENSIONAL REDUCTION TO SPECTRAL DATA FROM POLISHING SUBSTRATES

A plurality of spectra reflected from one or more substrates at a plurality of different positions on the one or more substrates are represented in the form of a first matrix, and the first matrix is decomposed into products of at least two component matrixes of a first set of component matrixes. The dimensions of each of the at least two component matrixes is reduced to produce a second set of component matrixes containing the at least two matrixes with reduced dimensions. 119-. (canceled)20. A method of polishing comprising:polishing a substrate with a rotating polishing pad in a polishing system;measuring a plurality of spectra of light reflected from the substrate during polishing with an in-situ spectrographic monitoring system, the plurality of spectra represented in the form of a first matrix,decomposing the first matrix into products of at least two component matrixes of a first set of component matrixes, a first component matrix of the at least two component matrixes providing eigenvectors for the first matrix;reducing dimensions of each of the at least two component matrixes to produce a second set of component matrixes containing the at least two matrixes with reduced dimensions, the at least two matrixes including the first component matrix with reduced dimensions;generating a product of the first component matrix with reduced dimensions and a matrix representing one or more spectra; andcontrolling the polishing system based on the product.21. The method of claim 20 , wherein decomposing the first matrix comprises applying singular value decomposition claim 20 , applying CUR matrix approximation claim 20 , or applying principal component analysis.22. The method of claim 20 , comprising generating a characterizing value based on the product claim 20 , the characterizing value being associated with a property of the substrate claim 20 , and controlling the polishing operation based on the characterizing value.23. The method of claim 22 , comprising ...

PEAK-BASED ENDPOINTING FOR CHEMICAL MECHANICAL POLISHING

A method of polishing includes storing a predetermined location and a predetermined number as criteria for detecting an end point, polishing a substrate, measuring a sequence of current spectra of light reflected from the substrate while the substrate is being polished, identifying a plurality of peaks or valleys that persist with an evolving location through at least some of the sequence of current spectra, counting a number of peaks or valleys that were identified that pass the predetermined location as polishing progresses, and ceasing to polish the substrate when the number counted reaches the predetermined number. 113-. (canceled)14. A method comprising:storing a predetermined location and a predetermined number as criteria for detecting an end point;polishing a substrate;measuring a sequence of current spectra of light reflected from the substrate while the substrate is being polished;identifying a plurality of peaks or valleys in the sequence of current spectra, wherein the peaks or valleys persist with an evolving location through at least some of the sequence of current spectra;counting a number of peaks or valleys that were identified that pass the predetermined location as polishing progresses; andceasing to polish the substrate when the number counted reaches the predetermined number.15. The method of claim 14 , wherein counting the number of peaks or valleys comprises measuring a first location of a peak or valley in a first current spectrum of the sequence of current spectra claim 14 , and measuring a second location of the peak or valley in a second current spectrum of the sequence of current spectra.16. The method of claim 15 , wherein counting the number of peaks or valleys comprises determining whether the first location is on one side of the predetermined location and the second location is on an opposite side of the predetermined location.17. The method of claim 16 , wherein the first current spectrum is measured during a first rotation of a ...

Multi-Platen Multi-Head Polishing Architecture

A polishing apparatus includes a plurality of stations supported on a platform, the plurality of stations including at least two polishing stations and a transfer station, each polishing station including a platen to support a polishing pad, a plurality of carrier heads suspended from and movable along a track such that each polishing station is selectively positionable at the stations, and a controller configured to control motion of the carrier heads along the track such that during polishing at each polishing station only a single carrier head is positioned in the polishing station. 117-. (canceled)18. A method of operating a polishing apparatus , comprising:transporting a first substrate from a transfer station past a first polishing station to a second polishing station without polishing the first substrate at the first polishing station;transporting a second substrate from the transfer station to the first polishing station;polishing the first substrate at the second polishing station and simultaneously polishing the second substrate at the first polishing station;transporting the first substrate from the second polishing station past a third polishing station to a fourth polishing station without polishing the first substrate at the third polishing station;transporting the second substrate from the first polishing station past the second polishing station to the third polishing station without polishing the second at the second polishing station; andpolishing the first substrate at the fourth polishing station and simultaneously polishing the second substrate at the third polishing station.19. The method of claim 18 , further comprising transporting the first substrate from the fourth polishing station to the transfer station claim 18 , and transporting the second substrate from the third polishing station past the fourth polishing station to the transfer station without polishing the second substrate at the fourth polishing station.20. The method of claim 18 ...

Machine vision as input to a cmp process control algorithm

During chemical mechanical polishing of a substrate, a signal value that depends on a thickness of a layer in a measurement spot on a substrate undergoing polishing is determined by a first in-situ monitoring system. An image of at least the measurement spot of the substrate is generated by a second in-situ imaging system. Machine vision processing, e.g., a convolutional neural network, is used to determine a characterizing value for the measurement spot based on the image. Then a measurement value is calculated based on both the characterizing value and the signal value.

DETERMINATION OF GAIN FOR EDDY CURRENT SENSOR

In one aspect, a method of controlling polishing includes receiving a measurement of an initial thickness of a conductive film on a first substrate prior to polishing the first substrate from an in-line or stand-alone monitoring system, polishing one or more substrates in a polishing system, the one or more substrates including the first substrate, during polishing of the one or more substrates, monitoring the one or more substrates with an eddy current monitoring system to generate a first signal, determining a starting value of the first signal for a start of polishing of the first substrate, determining a gain based on the starting value and the measurement of the initial thickness, for at least a portion of the first signal collected during polishing of at least one substrate of the one or more substrates, and calculating a second signal based on the first signal and the gain. 1. A method of controlling polishing , comprising:receiving a measurement of an initial thickness of a conductive film on a first substrate prior to polishing the first substrate from an in-line or stand-alone monitoring system;polishing one or more substrates in a polishing system, the one or more substrates including the first substrate;during polishing of the one or more substrates, monitoring the one or more substrates with an eddy current monitoring system to generate a first signal;determining a starting value of the first signal for a start of polishing of the first substrate;determining a gain based on the starting value and the measurement of the initial thickness;for at least a portion of the first signal collected during polishing of at least one substrate of the one or more substrates, calculating a second signal based on the first signal and the gain; anddetermining at least one of a polishing endpoint or an adjustment to a polishing parameter for the at least one of the substrate based on the second signal.2. The method of claim 1 , wherein calculating the second signal ...

Determination of gain for eddy current sensor

A method of controlling polishing includes polishing a substrate at a first polishing station, monitoring the substrate with a first eddy current monitoring system to generate a first signal, determining an ending value of the first signal for an end of polishing of the substrate at the first polishing station, determining a first temperature at the first polishing station, polishing the substrate at a second polishing station, monitoring the substrate with a second eddy current monitoring system to generate a second signal, determining a starting value of the second signal for a start of polishing of the substrate at the second polishing station, determining a gain for the second polishing station based on the ending value, the starting value and the first temperature, and calculating a third signal based on the second signal and the gain.

CORE CONFIGURATION FOR IN-SITU ELECTROMAGNETIC INDUCTION MONITORING SYSTEM

An apparatus for chemical mechanical polishing includes a support for a polishing pad having a polishing surface, and an electromagnetic induction monitoring system to generate a magnetic field to monitor a substrate being polished by the polishing pad. The electromagnetic induction monitoring system includes a core and a coil wound around a portion of the core. The core includes a back portion, a center post extending from the back portion in a first direction normal to the polishing surface, and an annular rim extending from the back portion in parallel with the center post and surrounding and spaced apart from the center post by a gap. A width of the gap is less than a width of the center post, and a surface area of a top surface of the annular rim is at least two times greater than a surface area of a top surface of the center post. 1. An apparatus for chemical mechanical polishing , comprising:a support for a polishing pad having a polishing surface; and a back portion,', 'a center post extending from the back portion in a first direction normal to the polishing surface, the center post having a first width in a second direction parallel to the polishing surface, and', 'an annular rim extending from the back portion in parallel with the center post and surrounding and spaced apart from the center post by a gap, the annular rim having a second width in the second direction and the gap having a third width in the second direction,, 'an electromagnetic induction monitoring system to generate a magnetic field to monitor a substrate being polished by the polishing pad, the electromagnetic induction monitoring system comprising a core and a coil wound around a portion of the core, the core including'}wherein the third width is less than the first width, and a surface area of a top surface of the annular rim is at least two times greater than a surface area of a top surface of the center post.2. The apparatus of claim 1 , wherein the second width is greater than the ...

GROUPING SPECTRAL DATA FROM POLISHING SUBSTRATES

Among other things, a computer-based method is described. The method comprises receiving, by one or more computers, a plurality of measured spectra reflected from a substrate at a plurality of different positions on the substrate. The substrate comprises at least two regions having different structural features. The method also comprises performing, by the one or more computers, a clustering algorithm on the plurality of measured spectra to separate the plurality of measured spectra into a number of groups based on the spectral characteristics of the plurality of measured spectra; selecting one of the number of groups to provide a selected group having a subset of spectra from the plurality of measured spectra; and determining, in the one or more computers, at least one characterizing value for the substrate based on the subset of spectra of the selected group. 1. A computer-based method comprising:receiving, by one or more computers, a plurality of measured spectra reflected from a substrate at a plurality of different positions on the substrate, the substrate comprising at least two regions having different structural features;performing, by the one or more computers, a clustering algorithm on the plurality of measured spectra to separate the plurality of measured spectra into a number of groups based on the spectral characteristics of the plurality of measured spectra;selecting one of the number of groups to provide a selected group having a subset of spectra from the plurality of measured spectra; anddetermining, in the one or more computers, at least one characterizing value for the substrate based on the subset of spectra of the selected group.2. The method of claim 1 , wherein the characterizing value is a thickness of an outermost layer of the substrate.3. The method of claim 1 , wherein the clustering algorithm comprises a k-means clustering algorithm.412-. (canceled)13. The method of claim 1 , wherein the number of groups is chosen to be larger than the ...

REDUCING NOISE IN SPECTRAL DATA FROM POLISHING SUBSTRATES

Among other things, a machine based method comprises representing a plurality of spectra reflected from one or more substrates at a plurality of different positions on the one or more substrates in the form of a first matrix; decomposing, by one or more computers, the first matrix into products of at least two component matrixes of a first set of component matrixes; reducing dimensions of each of the at least two component matrixes to produce a second set of component matrixes containing the at least two matrixes with reduced dimensions; and generating, by the one or more computers, a second matrix by taking a product of the matrixes of the second set of component matrixes. 1. A machine-based method comprising:representing a plurality of spectra reflected from one or more substrates at a plurality of different positions on the one or more substrates in the form of a first matrix, each spectrum being represented by a dataset arranged in a single row or a single column of the first matrix, and the spectra being reflected when an outer layer of the one or more substrates has substantially the same thickness at the plurality of positions;decomposing, by one or more computers, the first matrix into products of at least two component matrixes of a first set of component matrixes;reducing dimensions of each of the at least two component matrixes to produce a second set of component matrixes containing the at least two matrixes with reduced dimensions; andgenerating, by the one or more computers, a second matrix by taking a product of the matrixes of the second set of component matrixes, the second matrix having the same dimensions as the first matrix, and each single row or each single column of the second matrix comprising a modified dataset representing a modified spectrum corresponding to the spectrum represented by a respective single row or single column of the first matrix.2. The method of claim 1 , comprising generating claim 1 , by the one or more computers claim 1 ...

APPLYING DIMENSIONAL REDUCTION TO SPECTRAL DATA FROM POLISHING SUBSTRATES

A plurality of spectra reflected from one or more substrates at a plurality of different positions on the one or more substrates are represented in the form of a first matrix, and the first matrix is decomposed into products of at least two component matrixes of a first set of component matrixes. The dimensions of each of the at least two component matrixes is reduced to produce a second set of component matrixes containing the at least two matrixes with reduced dimensions. 119-. (canceled)20. A method of polishing comprising:polishing a substrate with a rotating polishing pad in a polishing system;measuring a multiplicity of spectra of light reflected from the substrate with an in-situ spectrographic monitoring system, the multiplicity of spectra including a plurality of spectra collected during a single rotation of the polishing pad from at a plurality of different positions on the substrate, the plurality of spectra represented in the form of a first matrix, each spectrum of the plurality of spectra being represented by a dataset arranged in a single row or a single column of the first matrix;decomposing the first matrix into products of at least two component matrixes of a first set of component matrixes;reducing dimensions of each of the at least two component matrixes to produce a second set of component matrixes containing the at least two matrixes with reduced dimensions;generating a second matrix by taking a product of the matrixes of the second set of component matrixes, the second matrix having the same dimensions as the first matrix, and each single row or each single column of the second matrix comprising a modified dataset representing a modified spectrum corresponding to the spectrum represented by a respective single row or single column of the first matrix; andcontrolling the polishing system based on the second matrix.21. The method of claim 20 , comprising generating a characterizing value based on the second matrix claim 20 , the characterizing ...

Display of Spectra Contour Plots Versus Time For Semiconductor Processing System Control

A method to assist in identifying a spectral feature and a characteristic of the selected spectral feature to monitor during polishing includes polishing a test substrate and measuring a sequence of spectra of light reflected from a substrate while the substrate is being polished, where at least some of the spectra of the sequence differ due to material being removed during the polishing. The sequence of spectra are visually displayed as a contour plot. 122-. (canceled)23. A method to assist in identifying a spectral feature and a characteristic of the selected spectral feature to monitor during polishing , comprising:polishing a test substrate;measuring a sequence of spectra of light reflected from the substrate while the substrate is being polished with an in-situ monitoring system, at least some of the spectra of the sequence differing due to material being removed during the polishing;receiving the measurements of sequence of spectra from the in-situ monitoring system in a computer; andvisually displaying the sequence of spectra as a contour plot on a computer monitor by the computer.24. The method of claim 23 , wherein the contour plot comprises color coding of intensity values.25. The method of claim 23 , wherein the contour plot comprises a 3-D plot of intensity values.26. The method of claim 24 , wherein color coding comprises assigning red to higher intensity values in the spectra claim 24 , blue to lower intensity values in the spectrum claim 24 , and intermediate colors to intermediate intensity values in the spectra.27. The method of claim 23 , wherein the contour plot comprises a greyscale coding of intensity values.28. The method of claim 23 , comprising claim 23 , while the contour plot is visually displayed on the computer monitor claim 23 , receiving a selection of a feature of a spectrum and a characteristic of the feature to track during polishing of a device substrate.29. The method of claim 28 , further comprising:polishing the device substrate; ...

CORE CONFIGURATION WITH ALTERNATING POSTS FOR IN-SITU ELECTROMAGNETIC INDUCTION MONITORING SYSTEM

An apparatus for chemical mechanical polishing includes a platen having a surface to support a polishing pad and an electromagnetic induction monitoring system to generate a magnetic field to monitor a substrate being polished by the polishing pad. The electromagnetic induction monitoring system includes a core positioned at least partially in the platen and a coil wound around a portion of the core. The core includes a back portion and a multiplicity of posts extending from the back portion in a first direction normal to the surface of the platen. The core and coil are configured such that the multiplicity of posts include a first plurality of posts to provide a first magnetic polarity and a second plurality of posts to provide an opposite second magnetic polarity, and the first plurality of posts and the second plurality of posts are arranged in an alternating pattern. 1. An apparatus for chemical mechanical polishing , comprising:a platen having a surface to support a polishing pad; and a back portion, and', 'a multiplicity of posts extending from the back portion in a first direction normal to the surface of the platen,, 'an electromagnetic induction monitoring system to generate a magnetic field to monitor a substrate being polished by the polishing pad, the electromagnetic induction monitoring system comprising a core positioned at least partially in the platen and a coil wound around a portion of the core, the core including'}wherein the core and coil are configured such that the multiplicity of posts comprise a first plurality of posts to provide a first magnetic polarity and a second plurality of posts to provide an opposite second magnetic polarity, the first plurality of posts and the second plurality of posts arranged in an alternating pattern.2. The apparatus of claim 1 , wherein the multiplicity of posts is evenly divided between the first plurality of posts and the second plurality of posts.3. The apparatus of claim 2 , wherein the multiplicity of ...

Endpointing detection for chemical mechanical polishing based on spectrometry

A method of detecting a polishing endpoint includes storing a plurality of library spectra, measuring a sequence of spectra from the substrate in-situ during polishing, and for each measured spectrum of the sequence of spectra, finding a best matching library spectrum from the plurality of library spectra to generate a sequence of best matching library spectra. Each library spectrum has a stored associated value representing a degree of progress through a polishing process, and the stored associated value for the best matching library spectrum is determined for each best matching library spectrum to generate a sequence of values representing a progression of polishing of the substrate. The sequence of values is compared to a target value, and a polishing endpoint is triggered when the sequence of values reaches the target value.

IMAGING FOR MONITORING THICKNESS IN A SUBSTRATE CLEANING SYSTEM

A substrate cleaning system includes a cleaner module to clean a substrate after polishing of the substrate, a drier module to dry the substrate after cleaning by the cleaner module, a substrate support movable along a first axis from a first position in the drier module to a second position outside the drier module, and an in-line metrology station including a line-scan camera positioned to scan the substrate as the substrate is held by the substrate support and the substrate support is between the first position to the second position. The first axis is substantially parallel to a face of the substrate as held in by the substrate support. 1. A substrate cleaning system , comprising:a cleaner module to clean a substrate after polishing of the substrate;a drier module to dry the substrate after cleaning by the cleaner module;a substrate support movable along a first axis that is substantially parallel to a face of the substrate as held in by the substrate support from a first position in the drier module to a second position outside the drier module; andan in-line metrology station including a line-scan camera positioned configured to scan the substrate as the substrate is held by the substrate support and the substrate support is moving between the first position to the second position.2. The substrate cleaning system of claim 1 , comprising a housing to separate the cleaner module and drier module from other modules of a polishing apparatus claim 1 , and a window in the housing claim 1 , and wherein the line-scan camera is positioned outside the housing to scan the substrate through the window.3. The substrate cleaning system of claim 2 , comprising a first mirror positioned inside the housing and configured to reflect light from the substrate to the window.4. The substrate cleaning system of claim 3 , comprising a second mirror positioned outside the housing and configured to reflect the light from the first mirror into the line-scan camera.5. The substrate ...

PASSIVE ACOUSTIC MONITORING AND ACOUSTIC SENSORS FOR CHEMICAL MECHANICAL POLISHING

A chemical mechanical polishing apparatus includes a platen to support a polishing pad, a carrier head to a surface of a substrate against the polishing pad, a motor to generate relative motion between the platen and the carrier head so as to polish an overlying layer on the substrate, an in-situ acoustic monitoring system, and a controller. The controller is configured to detect exposure of an underlying layer due to the polishing of the substrate based on measurements from the in-situ acoustic monitoring system. The in-situ acoustic monitoring system may detect exposure of an underlying layer based on comparison of the signal to prior measurements of acoustic signals generated by stress energy of test substrates. 1. A chemical mechanical polishing apparatus , comprising:a platen to support a polishing pad;a carrier head to hold a surface of a substrate against the polishing pad;a motor to generate relative motion between the platen and the carrier head so as to polish an overlying layer on the substrate;an in-situ acoustic monitoring system including an acoustic signal sensor that receives acoustic signals generated by stress energy the substrate; anda controller configured to detect exposure of an underlying layer due to the polishing of the substrate based on measurements from the in-situ acoustic monitoring system based on comparison of the signal to prior measurements of acoustic signals generated by stress energy of test substrates.2. The apparatus of claim 1 , wherein the acoustic signal generator is configured to monitor acoustic energy at a frequency to 200 KHz to 1 MHz.3. The apparatus of claim 1 , wherein the acoustic signal generator is configured to monitor acoustic energy at a frequency to 200 KHz to 400 kHz.4. The apparatus of claim 1 , wherein the controller is configured to:perform frequency domain analysis to determine changes in relative power of spectral frequencies.5. The apparatus of claim 4 , wherein the controller is configured to determine ...

ACTIVE ACOUSTIC MONITORING FOR CHEMICAL MECHANICAL POLISHING

A chemical mechanical polishing apparatus includes a platen to support a polishing pad, a carrier head to a surface of a substrate against the polishing pad, a motor to generate relative motion between the platen and the carrier head so as to polish an overlying layer on the substrate, an in-situ acoustic monitoring system, and a controller. The in-situ acoustic monitoring system includes an acoustic signal generator to emit acoustic signals and an acoustic signal sensor that receives acoustic signals reflected from the surface of the substrate. The controller is configured to detect exposure of an underlying layer due to the polishing of the substrate based on measurements from the in-situ acoustic monitoring system. 1. A chemical mechanical polishing apparatus , comprising:a platen to support a polishing pad;a carrier head to hold a surface of a substrate against the polishing pad;a motor to generate relative motion between the platen and the carrier head so as to polish an overlying layer on the substrate;an in-situ acoustic monitoring system including an acoustic signal generator to emit acoustic signals and an acoustic signal sensor that receives acoustic signals reflected from the surface of the substrate; anda controller configured to detect exposure of an underlying layer due to the polishing of the substrate based on measurements from the in-situ acoustic monitoring system.2. The apparatus of claim 1 , wherein the in-situ acoustic monitoring system includes a waveguide positioned to couple the acoustic signal sensor to slurry in a groove in the polishing pad.3. The apparatus of claim 2 , wherein the polishing pad has a polishing layer and a plurality of slurry-transport grooves in a polishing surface of the polishing layer claim 2 , and wherein the waveguide extends through the polishing pad and into the groove.4. The apparatus of claim 1 , wherein the acoustic signal sensor comprises a piezoelectric acoustic sensor.5. The apparatus of claim 1 , wherein the ...

DETERMINATION OF GAIN FOR EDDY CURRENT SENSOR

A method of controlling polishing includes polishing a substrate at a first polishing station, monitoring the substrate with a first eddy current monitoring system to generate a first signal, determining an ending value of the first signal for an end of polishing of the substrate at the first polishing station, determining a first temperature at the first polishing station, polishing the substrate at a second polishing station, monitoring the substrate with a second eddy current monitoring system to generate a second signal, determining a starting value of the second signal for a start of polishing of the substrate at the second polishing station, determining a gain for the second polishing station based on the ending value, the starting value and the first temperature, and calculating a third signal based on the second signal and the gain. 1. A method of controlling polishing , comprising:polishing a substrate at a first polishing station;during polishing of the substrate at the first polishing station, monitoring the substrate with a first eddy current monitoring system to generate a first signal;determining an ending value of the first signal for an end of polishing of the substrate at the first polishing station;determining a first temperature at the first polishing station;after polishing the substrate at the first polishing station, polishing the substrate at a second polishing station;during polishing of the substrate at the second polishing station, monitoring the substrate with a second eddy current monitoring system to generate a second signal;determining a starting value of the second signal for a start of polishing of the substrate at the second polishing station;determining a gain for the second polishing station based on the ending value, the starting value and the first temperature;for at least a portion of the second signal collected during polishing of at least one substrate at the second polishing station, calculating a third signal based on the ...

Endpoint control of multiple substrates of varying thickness on the same platen in chemical mechanical polishing

A difference between a first expected required polish time for a first substrate and a second expected required polish time for a second substrate is determined using a first pre-polish thickness and a second pre-polish thickness measured at an in-line metrology station. A duration of an initial period is determined based on the difference between the first expected required polish time and the second expected required polish time. For the initial period at a beginning of a polishing operation, no pressure is applied to whichever of the first substrate and the second substrate has a lesser expected required polish time while simultaneously pressure is applied to whichever of the first substrate and the second substrate has a greater expected required polish time. After the initial period, pressure is applied to both the first substrate and the second substrate.

COLOR IMAGING FOR CMP MONITORING

A polishing system includes a polishing station including a platen to support a polishing pad, a support to hold a substrate, an in-line metrology station to measure the substrate before or after polishing of a surface of the substrate in the polishing station, and a controller. The in-line metrology station includes a color line-scan camera, a white light source, a frame supporting the light source and the camera, and a motor to cause relative motion between the camera and the support along a second axis perpendicular to the first axis to cause the light source and the camera to scan across the substrate. The controller is configured to receive a color data from the camera, to generate a 2-dimensional color image from the color data, and to control polishing at the polishing station based on the color image. 1. A polishing system , comprising:a polishing station including a platen to support a polishing pad;a support to hold a substrate; a color line-scan camera having detector elements arranged along a first axis that is parallel to the surface of the substrate during scanning of the substrate,', 'an elongated white light source having a longitudinal axis parallel to the first axis and configured to direct light toward the substrate at a non-zero incidence angle during scanning of the substrate,', 'a frame supporting the light source and the camera, and', 'a motor to cause relative motion between the frame and the support along a second axis perpendicular to the first axis to cause the light source and the camera to scan across the substrate; and, 'an in-line metrology station to measure the substrate before or after polishing of a surface of the substrate in the polishing station, the in-line metrology station including'}a controller configured to receive a color data from the camera, to generate a 2-dimensional color image from the color data, and to control polishing at the polishing station based on the color image.2. The system of claim 1 , comprising a ...

ENDPOINT CONTROL OF MULTIPLE SUBSTRATE ZONES OF VARYING THICKNESS IN CHEMICAL MECHANICAL POLISHING

A difference between a first expected required polish time for a first substrate and a second expected required polish time for a second substrate is determined using a first pre-polish thickness and a second pre-polish thickness measured at an in-line metrology station. A duration of an initial period is determined based on the difference between the first expected required polish time and the second expected required polish time. For the initial period at a beginning of a polishing operation, no pressure is applied to whichever of the first substrate and the second substrate has a lesser expected required polish time while simultaneously pressure is applied to whichever of the first substrate and the second substrate has a greater expected required polish time. After the initial period, pressure is applied to both the first substrate and the second substrate. 120-. (canceled)21. A computer-implemented method of polishing , comprising:measuring a plurality of thicknesses in a plurality of zones on one or more substrates;polishing the one or more substrates with a polishing pad, wherein pressures applied to the plurality of zones are independently controllable;determining a difference between a plurality of expected required polish times for the plurality of zones on the one or more substrates based on the plurality of thicknesses;determining a pressure ratio to apply between the plurality of zones on the one or more substrates using the difference such that the plurality of zones have closer to the same thickness at an intermediate time before a projected endpoint time than without such a pressure difference; andat least until the intermediate time, applying pressures to the plurality of zones on the one or more substrates at the pressure ratio.22. The method of claim 21 , wherein the pressure ratio equals a ratio between the plurality of expected required polish times.23. The method of claim 21 , further comprising storing a plurality of target thickness for the ...

ENDPOINT METHOD USING PEAK LOCATION OF SPECTRA CONTOUR PLOTS VERSUS TIME

In one aspect, a method of polishing includes polishing a substrate, and receiving an identification of a selected spectral feature and a characteristic of the selected spectral feature to monitor during polishing. The method includes measuring a sequence of spectra of light reflected from the substrate while the substrate is being polished, where at least some of the spectra of the sequence differ due to material being removed during the polishing. The method of polishing includes determining a value of a characteristic of the selected spectral feature for each of the spectra in the sequence of spectra to generate a sequence of values for the characteristic, fitting a function to the sequence of values, and determining either a polishing endpoint or an adjustment for a polishing rate based on the function. 122-. (canceled)23. A method to assist in identifying a spectral feature and a characteristic of the selected spectral feature to monitor during polishing , comprising:polishing a test substrate;measuring a sequence of spectra of light reflected from a substrate while the substrate is being polished, at least some of the spectra of the sequence differing due to material being removed during the polishing;visually displaying the sequence of spectra as a contour plot.24. The method of claim 23 , wherein the contour plot comprises color coding of intensity values.25. The method of claim 23 , wherein the contour plot comprises a 3-D plot of intensity values.26. A computer program product claim 23 , tangibly embodied on a computer readable medium claim 23 , comprising instructions to:receive an identification of a selected spectral feature, a characteristic of the selected spectral feature to monitor during polishing, an expected initial value for the characteristic and a target difference for the characteristic;receiving measurements of a sequence of spectra of light reflected from a substrate while the substrate is being polished, at least some of the spectra of the ...

DETERMINATION OF GAIN FOR EDDY CURRENT SENSOR

A method of controlling polishing includes polishing a substrate at a first polishing station, monitoring the substrate with a first eddy current monitoring system to generate a first signal, determining an ending value of the first signal for an end of polishing of the substrate at the first polishing station, determining a first temperature at the first polishing station, polishing the substrate at a second polishing station, monitoring the substrate with a second eddy current monitoring system to generate a second signal, determining a starting value of the second signal for a start of polishing of the substrate at the second polishing station, determining a gain for the second polishing station based on the ending value, the starting value and the first temperature, and calculating a third signal based on the second signal and the gain. 118-. (canceled)19. A polishing system , comprising:a first polishing station including a first platen to support a first polishing pad, a first in-situ eddy current monitoring system including a first sensor to generate a first signal depending on a thickness of a conductive layer on a substrate, and a first temperature sensor;a second polishing station including a second platen to support a second polishing pad and a second in-situ eddy current monitoring system including a second sensor to generate a second signal depending on the thickness of the conductive layer on the substrate;a carrier head to hold the substrate; and receive a second signal from a second eddy current monitoring system during polishing of the substrate at the second polishing station;', 'determine a starting value of the second signal for a start of polishing of the substrate at the second polishing station;', 'determine a gain for the second polishing station based on the ending value, the starting value and a first temperature measured by the first temperature sensor;', 'for at least a portion of the second signal collected during polishing of at least ...

WEIGHTED REGRESSION OF THICKNESS MAPS FROM SPECTRAL DATA

A method of controlling a polishing operation includes measuring a plurality of spectra at a plurality of different positions on a substrate to provide a plurality of measured spectra. For each measured spectrum of the plurality of measured spectra, a characterizing value is generated based on the measured spectrum. For each characterizing value, a goodness of fit of the measured spectrum to another spectrum used in generating the characterizing value is determined. A wafer-level characterizing value map is generated by applying a regression to the plurality of characterizing values with the plurality of goodnesses of fit used as weighting factors in the regression. A polishing endpoint or a polishing parameter of the polishing apparatus is adjusted based on the wafer-level characterizing map, and the substrate or a subsequent substrate is polished in the polishing apparatus with the adjusted polishing endpoint or polishing parameter. 1. A method of controlling a polishing operation , comprising:measuring a plurality of spectra reflected from a substrate at a plurality of different positions on the substrate with an in-sequence or in-situ monitoring system to provide a plurality of measured spectra;for each measured spectrum of the plurality of measured spectra, generating a characterizing value based on the measured spectrum;for each characterizing value, determining a goodness of fit of the measured spectrum to another spectrum used in generating the characterizing value to provide a plurality of goodnesses of fit;generating a wafer-level characterizing value map by applying a regression to the plurality of characterizing values with the plurality of goodnesses of fit used as weighting factors in the regression;adjusting a polishing endpoint or a polishing parameter of the polishing apparatus based on the wafer-level characterizing map; andpolishing the substrate or a subsequent substrate in the polishing apparatus with the adjusted polishing endpoint or polishing ...

FEED FORWARD PARAMETER VALUES FOR USE IN THEORETICALLY GENERATING SPECTRA

A method of controlling a polishing operation is described. A controller stores an optical model for a layer stack having a plurality of layers and a plurality of input parameters including a first parameter and a second parameter. The controller stores data defining a plurality of default values for the first parameter and measures an optical property of a substrate and generates a second value. Using the optical model and the second value and iterating over the first values, a number of reference spectra are calculated. A spectrum is measured and the measured spectrum is matched to the reference spectra and the best matched reference spectrum is determined. The first value of the best matched reference spectrum is determined and is used to adjust a polishing endpoint or a polishing parameter of a polishing apparatus. 1. A method of controlling a polishing operation , comprising:storing an optical model for a layer stack having a plurality of layers, the optical model having a plurality of input parameters including a first parameter and a second parameter;storing data defining a plurality of default first values for the first parameter;measuring an optical property of a substrate at a stand-alone or in-sequence metrology station to generate a second value for the second parameter;for each first value from the plurality of first values, calculating a reference spectrum using the optical model based on the first value and the second value, to generate a plurality of reference spectra;transporting the substrate from the stand-alone or in-sequence metrology station to an in-sequence or in-situ monitoring system of a chemical mechanical polishing apparatus;measuring a spectrum with the in-sequence or in-situ monitoring system to provide a measured spectrum;determining a best matching reference spectrum from the plurality of reference spectra that provides a best match to the measured spectrum;determining the first value associated with the best matching reference ...

COLOR IMAGING FOR CMP MONITORING

A metrology technique for analyzing a substrate includes storing data indicating a boundary of an area in a 2-dimensional color space having a pair of color channels including a first color channel and a second color channel as axes of the color space, receiving color data of a substrate from a camera, generating a color image of the substrate from the color data, performing a comparison of a pair of color values for the pair of color channels for the pixel to the boundary of the area in the 2-dimensional color space for each pixel of a plurality of pixels of the color image to determine whether the pair of color values meet thresholds provided by the boundary, and generating a signal to an operator based on results of the comparison for the plurality of pixels. 1. A computer program product , comprising a non-transitory computer readable medium encoded with instructions to cause one or more processors to:store data indicating a boundary of an area in a 2-dimensional color space, the 2-dimensional color space having a pair of color channels including a first color channel and a second color channel as axes of the color space;receive color data of a substrate from a camera;generate a color image of the substrate from the color data;for each pixel of a plurality of pixels of the color image, perform a comparison of a pair of color values for the pair of color channels for the pixel to the boundary of the area in the 2-dimensional color space to determine whether the pair of color values meet thresholds provided by the boundary; andgenerate a signal to an operator based on results of the comparison for the plurality of pixels.2. The computer program product of claim 1 , comprising instructions to count a number of pixels in the color image that fail to meet the thresholds and to compare the number of pixels to a second threshold.3. The computer program product of claim 2 , comprising instructions to store an image mask identifying one or regions on the substrate claim ...

Substrate features for inductive monitoring of conductive trench depth

A substrate for use in fabrication of an integrated circuit has a layer with a plurality of conductive interconnects. The substrate includes a semiconductor body, a dielectric layer disposed over the semiconductor body, a plurality of conductive lines of a conductive material disposed in first trenches in the dielectric layer to provide the conductive interconnects, and a closed conductive loop structure of the conductive material disposed in second trenches in the dielectric layer. The closed conductive loop is not electrically connected to any of the conductive lines.

X-RAY METROLOGY FOR CONTROL OF POLISHING

A method of controlling a polishing operation includes receiving a first measurement of a first amount of metal on a substrate made by a first x-ray monitoring system after a first metal layer is deposited on the substrate and before a second metal layer is deposited on the substrate, transferring the substrate to a carrier head of a chemical mechanical polishing apparatus the substrate after the second metal layer is deposited on the substrate, making a second measurement of a second amount of metal on the substrate with a second x-ray monitoring system in the chemical mechanical polishing apparatus, comparing the first measurement to the second measurement to determine a difference, and adjusting a polishing endpoint or a polishing parameter of the polishing apparatus based on the difference. 1. A method of controlling a polishing operation , comprising:receiving a first measurement of a first amount of metal on a substrate made by a first x-ray monitoring system after a first metal layer is deposited on the substrate and before a second metal layer is deposited on the substrate;transferring the substrate to a carrier head of a chemical mechanical polishing apparatus the substrate after the second metal layer is deposited on the substrate;making a second measurement of a second amount of metal on the substrate with a second x-ray monitoring system in the chemical mechanical polishing apparatus;comparing the first measurement to the second measurement to determine a difference; andadjusting a polishing endpoint or a polishing parameter of the polishing apparatus based on the difference.2. The method of claim 1 , comprising polishing the second metal layer of the substrate in a first polishing operation until a surface of the underlying material is exposed and metal features remain in recesses in the underlying material.3. The method of claim 2 , comprising polishing the metal features and the underlying material in a second polishing operation.4. The method of ...

POLISHING APPARATUS USING NEURAL NETWORK FOR MONITORING

A method of polishing a layer on the substrate at a polishing station includes the actions of monitoring the layer during polishing at the polishing station with an in-situ monitoring system to generate a plurality of measured signals for a plurality of different locations on the layer; generating, for each location of the plurality of different locations, an estimated measure of thickness of the location, the generating including processing the plurality of measured signals through a neural network; and at least one of detecting a polishing endpoint or modifying a polishing parameter based on each estimated measure of thickness. 1. A method of polishing a substrate , comprising:polishing a layer on the substrate at a polishing station;monitoring the layer during polishing at the polishing station with an in-situ monitoring system to generate a plurality of initial values for a plurality of different locations on the layer;inputting a first multiplicity of initial values from the plurality of initial values into a first plurality of corresponding input nodes of a neural network, the first multiplicity of initial values corresponding to a first multiplicity of locations from the plurality of different locations that are within a first region on the substrate, and wherein initial values from the plurality of initial values that are not input into input nodes of the neural network include a second multiplicity of initial values corresponding to a second multiplicity of locations from the plurality of different locations that are within a different second region on the substrate;receiving a first multiplicity of modified values from a plurality of corresponding output nodes of the neural network; andat least one of detecting a polishing endpoint or modifying a polishing parameter based on the first multiplicity of modified values and the second multiplicity of initial values.2. The method of claim 1 , wherein a number of input nodes of the neural network equals a number ...

RESISTIVITY-BASED ADJUSTMENT OF MEASUREMENTS FROM IN-SITU MONITORING

A first resistivity value and a correlation function relating thickness of a conductive layer having the first resistivity value to a signal from an in-situ monitoring system are stored. A second resistivity value for a conductive layer on a substrate is received. A sequence of signal values that depend on thickness of the conductive layer is received from an in-situ electromagnetic induction monitoring system that monitors the substrate during polishing. A sequence of thickness values is generated based on the sequence of signal values and the correlation function. For at least some thickness values of the sequence of thickness values adjusted thickness values are generated that compensate for variation between the first resistivity value and the second resistivity value to generate a sequence of adjusted thickness values. A polishing endpoint is detected or an adjustment for a polishing parameter is determined based on the sequence of adjusted thickness values. 1. A computer program product , tangibly encoded on a non-transitory computer readable media , comprising instructions to cause a computer system to:store a first resistivity value and a correlation function relating thickness of a conductive layer having the first resistivity value to a signal from an in-situ monitoring system;receive a second resistivity value for a conductive layer on a substrate;receive a sequence of signal values that depend on thickness of the conductive layer from an in-situ electromagnetic induction monitoring system that monitors the substrate during polishing;generate a sequence of thickness values based on the sequence of signal values and the correlation function;for at least some thickness values of the sequence of thickness values, generate adjusted thickness values that compensates for variation between the first resistivity value and the second resistivity value to generate a sequence of adjusted thickness values; andat least one of detecting a polishing endpoint or ...

RESISTIVITY-BASED CALIBRATION OF IN-SITU ELECTROMAGNETIC INDUCTIVE MONITORING

A first resistivity value and a correlation function relating thickness of a conductive layer having the first resistivity value to a signal from an in-situ monitoring system are stored. A second resistivity value for a conductive layer on a substrate is received. A sequence of signal values that depend on thickness of the conductive layer is received from an in-situ electromagnetic induction monitoring system that monitors the substrate during polishing. A sequence of thickness values is generated based on the sequence of signal values and the correlation function. For at least some thickness values of the sequence of thickness values adjusted thickness values are generated that compensate for variation between the first resistivity value and the second resistivity value to generate a sequence of adjusted thickness values. A polishing endpoint is detected or an adjustment for a polishing parameter is determined based on the sequence of adjusted thickness values. 1. A method of calibrating an in-situ electromagnetic induction monitoring system , comprising:storing a first resistivity value and a correlation function relating thickness of a conductive layer having the first resistivity value to a signal from the in-situ electromagnetic induction monitoring system;receiving a second resistivity value and a sheet resistance value for a first conductive layer on a calibration substrate;making a first signal value measurement of the first conductive layer on the calibration substrate using the in-situ electromagnetic induction monitoring system;making a second signal value measurement without the first conductive layer using the in-situ electromagnetic induction monitoring system; andcalculating an offset and a gain to apply to signals from the in-situ electromagnetic induction monitoring system to compensate for variation in the in-situ electromagnetic induction monitoring system and to compensate for variation between the first resistivity value and the second ...

Adjusting eddy current measurements

Among other things, a method of controlling polishing during a polishing process is described. The method includes receiving a measurement of a thickness, thick(t), of a conductive layer of a substrate undergoing polishing from an in-situ monitoring system at a time t; receiving a measured temperature, T(t), associated with the conductive layer at the time t; calculating resistivity ρ T of the conductive layer at the measured temperature T(t); adjusting the measurement of the thickness using the calculated resistivity ρ T to generate an adjusted measured thickness; and detecting a polishing endpoint or an adjustment for a polishing parameter based on the adjusted measured thickness.

THICKNESS MEASUREMENT OF SUBSTRATE USING COLOR METROLOGY

A system for obtaining a measurement representative of a thickness of a layer on a substrate includes a support to hold a substrate, an optical assembly to capture two color images with light impinging the substrate at different angles of incidence, and a controller. The controller is configured to store a function that provides a value representative of a thickness as a function of position along a predetermined path in a coordinate space of at least four dimensions. For a pixel in the two color images, the controller determines a coordinate in the coordinate space from the color data, determines a position of a point on the predetermined path that is closest to the coordinate, and calculates a value representative of a thickness from the function and the position of the point on the predetermined path. 1. A system for obtaining a measurement representative of a thickness of a layer on a substrate , comprising:a support to hold a substrate for integrated circuit fabrication;an optical assembly to capture a first color image of at least a portion of the substrate held by the support with light impinging the substrate at a first angle of incidence and a second color image of the at least a portion of the substrate held by the support with light impinging the substrate at a different second angle of incidence; and receive the first color image and the second color image from the optical assembly,', 'store a function that provides a value representative of a thickness as a function of position along a predetermined path in a coordinate space of at least four dimensions including a first color channel and a second color channel from the first color image and a third color channel and a fourth color channel from the second color image,', 'for a pixel of the first color image and a corresponding pixel in the second color image, determine a coordinate in the coordinate space from color data in the first color image for the pixel and the color data in the second color image ...

ENDPOINTING DETECTION FOR CHEMICAL MECHANICAL POLISHING BASED ON SPECTROMETRY

A method of detecting a polishing endpoint includes storing a plurality of library spectra, measuring a sequence of spectra from the substrate in-situ during polishing, and for each measured spectrum of the sequence of spectra, finding a best matching library spectrum from the plurality of library spectra to generate a sequence of best matching library spectra. Each library spectrum has a stored associated value representing a degree of progress through a polishing process, and the stored associated value for the best matching library spectrum is determined for each best matching library spectrum to generate a sequence of values representing a progression of polishing of the substrate. The sequence of values is compared to a target value, and a polishing endpoint is triggered when the sequence of values reaches the target value. 120-. (canceled)21. A method of controlling a chemical mechanical polishing operation , comprising:storing a plurality of library spectra, each library spectrum of the plurality of library spectra having a stored associated value representing a degree of progress through a polishing process;polishing a substrate;measuring a sequence of spectra from the substrate in-situ during polishing;for each measured spectrum of the sequence of spectra, finding a best matching library spectrum from the plurality of library spectra to generate a sequence of best matching library spectra;for each best matching library spectrum from the sequence of best matching library spectra, determining the stored associated value for the best matching library spectrum to generate a sequence of values representing a progression of polishing of the substrate;comparing the sequence of values to a target value; andtriggering a polishing endpoint when the sequence of values reaches the target value.22. The method of claim 21 , wherein each library spectrum of the plurality of library spectra has a unique associated value.23. The method of claim 21 , further comprising ...

Thickness Measurement of Substrate Using Color Metrology

A layer thickness measurement system includes a support to hold a substrate, an optical sensor to capture a color image of at least a portion of the substrate, and a controller. The controller is configured to receive the color image from the optical sensor, store a function that provides a value representative of a thickness as a function of position along a predetermined path in a coordinate space of at least two dimensions including a first color channel and a second color channel, for a pixel of the color image determine a coordinate of the pixel in the coordinate space from color data in the color image, determine a position of a point on the predetermined path that is closest to the coordinate, and calculate a value representative of a thickness from the function and the position of the point on the predetermined path. 1. A system for obtaining a measurement representative of a thickness of a layer on a substrate , comprising:a support to hold a substrate for integrated circuit fabrication;an optical sensor to capture a color image of at least a portion of the substrate held by the support; and receive the color image from the optical sensor,', 'perform a color correction on the color image to generate an adjusted color image having increased color contrast;', 'store a function that provides a value representative of a thickness as a function of position along a predetermined path in a coordinate space of at least two dimensions including a first color channel and a second color channel,', 'for a pixel of the adjusted color image, determine a coordinate of the pixel in the coordinate space from color data in the adjusted color image for the pixel,', 'determine a position of a point on the predetermined path that is closest to the coordinate of the pixel, and', 'calculate a value representative of a thickness from the function and the position of the point on the predetermined path., 'a controller configured to'}2. The system of claim 1 , wherein the controller ...

Monitoring of Vibrations During Chemical Mechanical Polishing

A chemical mechanical polishing apparatus includes a platen to support a polishing pad, the platen having a recess, a flexible membrane in the recess, and an in-situ vibration monitoring system to generate a signal. The in-situ acoustic monitoring system includes a vibration sensor supported by the flexible membrane and positioned to couple to an underside of the polishing pad. 1. A chemical mechanical polishing apparatus , comprising:a platen to support a polishing pad, the platen having a recess;a flexible membrane in the recess; andan in-situ vibration monitoring system to generate a signal, the in-situ vibration monitoring system including a vibration sensor supported by the flexible membrane and positioned to couple to an underside of the polishing pad.2. The apparatus of claim 1 , comprising the polishing pad claim 1 , the polishing pad having a polishing layer and a backing layer.3. The apparatus of claim 2 , comprising an aperture in the backing layer claim 2 , and wherein the vibration sensor directly contacts an underside of the polishing layer.4. The apparatus of claim 2 , wherein the polishing pad comprises a pad portion coupled to a remainder of the polishing pad by a material that is softer than the pad portion.5. The apparatus of claim 4 , wherein the material completely laterally surrounds the pad portion.6. The apparatus of claim 4 , the pad portion of the polishing pad and the remainder of the polishing pad the same material composition.7. The apparatus of claim 4 , wherein the polishing layer has grooves claim 4 , and the material is positioned at the bottom of the grooves.8. The apparatus of claim 1 , wherein a volume below the flexible membrane is pressurizable.9. The apparatus of claim 8 , wherein the flexible membrane provides an inflatable balloon.10. The apparatus of claim 8 , wherein the flexible membrane extends across the recess to seal the volume below the flexible membrane.11. The apparatus of claim 8 , comprising a pump to pressurize ...

POLISHING APPARATUS USING NEURAL NETWORK FOR MONITORING

A method of polishing a layer on the substrate at a polishing station includes the actions of monitoring the layer during polishing at the polishing station with an in-situ monitoring system to generate a plurality of measured signals for a plurality of different locations on the layer; generating, for each location of the plurality of different locations, an estimated measure of thickness of the location, the generating including processing the plurality of measured signals through a neural network; and at least one of detecting a polishing endpoint or modifying a polishing parameter based on each estimated measure of thickness. 1. A method of polishing a substrate , comprising:polishing a layer on the substrate at a polishing station;monitoring the layer during polishing at the polishing station with an in-situ monitoring system to generate a plurality of measured signals for a plurality of different locations on the layer;generating, for each location of the plurality of different locations, an estimated measure of thickness of the location, the generating including processing the plurality of measured signals through a neural network; andat least one of detecting a polishing endpoint or modifying a polishing parameter based on each estimated measure of thickness.2. The method of claim 1 , further comprising:obtaining a second plurality of measured signals for a second plurality of different locations on the layer; andgenerating, for each location of the second plurality of different locations, an estimated measure of thickness of the location based on the measured signal for the location, the generating including using a static formula relating multiple values of the measured signals to multiple values of estimated measure of thickness.3. The method of claim 1 , further comprising:obtaining a third plurality of measured signals for a layer on a second substrate, each of the third plurality of measured signals corresponding to a location of a third plurality of ...

Grouping Spectral Data From Polishing Substrates

Among other things, a computer-based method is described. The method comprises receiving, by one or more computers, a plurality of measured spectra reflected from a substrate at a plurality of different positions on the substrate. The substrate comprises at least two regions having different structural features. The method also comprises performing, by the one or more computers, a clustering algorithm on the plurality of measured spectra to separate the plurality of measured spectra into a number of groups based on the spectral characteristics of the plurality of measured spectra; selecting one of the number of groups to provide a selected group having a subset of spectra from the plurality of measured spectra; and determining, in the one or more computers, at least one characterizing value for the substrate based on the subset of spectra of the selected group. 1. A method of operating a polishing system , comprising:receiving, by one or more computers, a plurality of measured spectra reflected from a substrate at a plurality of different positions on the substrate, the substrate comprising at least two regions having different structural features;performing, by the one or more computers, a clustering algorithm on the plurality of measured spectra to separate the plurality of measured spectra into a number of groups based on the spectral characteristics of the plurality of measured spectra, wherein performing the clustering algorithm includes initializing a plurality of centroids by selecting at least a pair of spectra from the plurality of measured spectra with the pair of spectra meeting a distance metric criterion, and setting the plurality of centroid to have the spectral characteristics of the selected spectra;selecting one of the number of groups to provide a selected group having a subset of spectra from the plurality of measured spectra;determining, in the one or more computers, at least one characterizing value for the substrate based on the subset of ...

ENDPOINTING DETECTION FOR CHEMICAL MECHANICAL POLISHING BASED ON SPECTROMETRY

Methods and apparatus for spectrum-based endpointing. An endpointing method includes selecting a reference spectrum. The reference spectrum is a spectrum of white light reflected from a film of interest on a first substrate and has a thickness greater than a target thickness. The reference spectrum is empirically selected for particular spectrum-based endpoint determination logic so that the target thickness is achieved when endpoint is called by applying the particular spectrum-based endpoint logic. The method includes obtaining a current spectrum. The current spectrum is a spectrum of white light reflected from a film of interest on a second substrate when the film of interest is being subjected to a polishing step and has a current thickness that is greater than the target thickness. The method includes determining, for the second substrate, when an endpoint of the polishing step has been achieved. The determining is based on the reference and current spectra. 114-. (canceled)15. A computer implemented polishing method comprising:storing at least one normalized predetermined spectrum;polishing a substrate;measuring a sequence of current spectra from the substrate undergoing polishing with an in-situ optical monitoring system;normalizing each current spectrum in the sequence to generate a sequence of normalized current spectra, wherein normalizing includes determining a highest value and a lowest value within a range in the current spectrum and causing each normalized current spectrum of the sequence of normalized current spectra to have a peak-to-trough value equal to a peak-to-trough amplitude of the at least one normalized predetermined spectrum; anddetermining a polishing endpoint using the at least one normalized predetermined spectrum and the sequence of normalized current spectra.16. (canceled)17. A computer implemented polishing method comprising:polishing a substrate;measuring a sequence of current spectra from a substrate undergoing polishing with an in- ...

Substrate features for inductive monitoring of conductive trench depth

A substrate for use in fabrication of an integrated circuit has a layer with a plurality of conductive interconnects. The substrate includes a semiconductor body, a dielectric layer disposed over the semiconductor body, a plurality of conductive lines of a conductive material disposed in first trenches in the dielectric layer to provide the conductive interconnects, and a closed conductive loop structure of the conductive material disposed in second trenches in the dielectric layer. The closed conductive loop is not electrically connected to any of the conductive lines.

INDUCTIVE MONITORING OF CONDUCTIVE TRENCH DEPTH

In fabrication of an integrated circuit having a layer with a plurality of conductive interconnects, a layer of a substrate is polished to provide the layer of the integrated circuit. The layer of the substrate includes conductive lines to provide the conductive interconnects. The layer of the substrate includes a closed conductive loop formed of a conductive material in a trench. A depth of the conductive material in the trench is monitored using an inductive monitoring system and a signal is generated. Monitoring includes generating a magnetic field that intermittently passes through the closed conductive loop. A sequence of values over time is extracted from the signal, the sequence of values representing the depth of the conductive material over time. 1. A method of chemical mechanical polishing a substrate , comprising:in fabrication of an integrated circuit having a layer with a plurality of conductive interconnects, polishing a layer of a substrate to provide the layer of the integrated circuit, wherein the layer of the substrate includes conductive lines to provide the conductive interconnects, and wherein the layer of the substrate includes a closed conductive loop formed of a conductive material in a trench;monitoring a depth of the conductive material in the trench using an inductive monitoring system and generating a signal, wherein monitoring includes generating a magnetic field that intermittently passes through the closed conductive loop; andextracting from the signal a sequence of values over time, the sequence of values representing the depth of the conductive material over time; and detecting a polishing endpoint by determining from the sequence of values that a depth of the conductive material has reached a target depth, or', 'adjusting at least one pressure applied by a carrier head to the substrate during polishing of the layer based on the sequence of values such that different zones on the substrate have closer to the same endpoint time than ...

INDUCTIVE MONITORING OF CONDUCTIVE TRENCH DEPTH

In fabrication of an integrated circuit having a layer with a plurality of conductive interconnects, a layer of a substrate is polished to provide the layer of the integrated circuit. The layer of the substrate includes conductive lines to provide the conductive interconnects. The layer of the substrate includes a closed conductive loop formed of a conductive material in a trench. A depth of the conductive material in the trench is monitored using an inductive monitoring system and a signal is generated. Monitoring includes generating a magnetic field that intermittently passes through the closed conductive loop. A sequence of values over time is extracted from the signal, the sequence of values representing the depth of the conductive material over time. 120-. (canceled)21. A method of chemical mechanical polishing a substrate , comprising:placing the substrate in contact with a polishing surface and generating relative motion between the substrate and polishing surface;during polishing, sweeping a sensor of an in-situ inductive monitoring system across the substrate to generate a signal, the sensor generating a magnetic field that at least intermittently impinges the substrate; determining a base signal strength for a time period when the magnetic field impinges the substrate,', 'identifying one or more peaks in the signal for the time period and determining a signal strength for each peak, and', 'calculating a value from the sequence of values based on the signal strength of a peak; and, 'extracting from the signal a sequence of values over time, the sequence of values representing the depth of the conductive material over time, the extracting including'} detecting a polishing endpoint by determining from the sequence of values that a depth of the conductive material has reached a target depth, or', 'adjusting at least one pressure applied by a carrier head to the substrate during polishing of the layer based on the sequence of values such that different zones on ...

CORE CONFIGURATION FOR IN-SITU ELECTROMAGNETIC INDUCTION MONITORING SYSTEM

An apparatus for chemical mechanical polishing includes a support for a polishing pad having a polishing surface, and an electromagnetic induction monitoring system to generate a magnetic field to monitor a substrate being polished by the polishing pad. The electromagnetic induction monitoring system includes a core and a coil wound around a portion of the core. The core includes a back portion, a center post extending from the back portion in a first direction normal to the polishing surface, and an annular rim extending from the back portion in parallel with the center post and surrounding and spaced apart from the center post by a gap. A width of the gap is less than a width of the center post, and a surface area of a top surface of the annular rim is at least two times greater than a surface area of a top surface of the center post. 1. An apparatus for chemical mechanical polishing , comprising:a support for a polishing pad having a polishing surface; and a back portion,', 'a center post extending from the back portion in a first direction normal to the polishing surface, and', 'an annular rim extending from the back portion in parallel with the center post and surrounding and spaced apart from the center post by a gap, wherein a surface area of a top surface of the annular rim is three to six times greater than a surface area of a top surface of the center post., 'an electromagnetic induction monitoring system to generate a magnetic field to monitor a substrate being polished by the polishing pad, the electromagnetic induction monitoring system comprising a core and a coil wound around a portion of the core, the core including'}2. The apparatus of claim 1 , wherein the center post has a first width in a second direction parallel to the polishing surface claim 1 , the annular rim has a second width in the second direction claim 1 , and the gap has a third width in the second direction claim 1 , and wherein the third width is less than the first width.3. The ...

GST film thickness monitoring

In polishing a substrate having a layer of GST disposed over an underlying layer, during polishing, a non-polarized light beam is directed onto the layer of GST. The non-polarized light beam reflects from the first substrate to generate a reflected light beam having an infra-red component. A sequence of measurements of intensity of the infra-red component of the reflected light beam are generated, and, in a processor, a time at which the sequence of measurements exhibits a predefined feature is determined.

Feedback of layer thickness timing and clearance timing for polishing control

During polishing of a first substrate at a first polishing station, a sequence of measurements by a first in-situ monitoring system is monitored to determining a first time at which the first sequence exhibits a first predefined feature indicating a predetermined thickness of an overlying layer, and during polishing of the first substrate at a second polishing station, a sequence of measurements by a second in-situ monitoring system is monitored to determine a second time indicating clearance of the overlying layer and exposure of the underlying layer. The first time is used to calculate a first adjusted polishing pressure for a second substrate at the first polishing station, and the second time is used to calculate a second adjusted polishing pressure for the second substrate at the second polishing station.

Friction sensor for polishing system

Polishing pad with window

Polishing pads with a window, systems containing such polishing pads, and processes that use such polishing pads are disclosed. For example, a light beam (34) having a wavelength between about 300 and 500 nm may be directed through a transparent portion (44) of a polishing surface of a polishing pad (18) during polishing in one of a shallow trench isolation (STI) fabrication process, a spin-on glass fabrication process and a silicon-on-insulator (SOI) fabrication process. As another example, the polishing pad may include a backing layer (116), a polishing layer (120), a solid window (140), and layers of first and second different adhesive materials (150, 160) between the backing layer and the solid window.

In-Line Wafer Thickness Sensing

A method of forming bare silicon substrates is described. A bare silicon substrate is measured, wherein measuring is performed by a non-contact capacitance measurement device to obtain a signal at a point on the substrate. The signal or a thickness indicated by the signal is communicated to a controller. An adjusted polishing parameter according to the signal or thickness indicated by the signal is determined. After determining an adjusted polishing parameter, the bare silicon substrate is polished on a polisher using the adjusted polishing parameter.

System and method for in-line metal profile measurement

A system includes a measuring station for positioning an eddy current probe proximate to a substrate in a substrate holder. The probe can produce a time-varying magnetic field, in order to induce eddy currents in one or more conductive regions of a substrate either prior to or subsequent to polishing. The eddy current signals are detected, and may be used to update one or more polishing parameters for a chemical mechanical polishing system. The substrate holder may be located in a number places; for example, in a substrate transfer system, a factory interface module, a cleaner, or in a portion of the chemical mechanical polishing system away from the polishing stations. Additional probes may be used.

Polishing system with in-line and in-situ metrology

A computer-implemented method for process control in chemical mechanical polishing in which an initial pre-polishing thickness of a substrate is measured at a metrology station, a parameter of an endpoint algorithm is determined from the initial thickness of the substrate, a substrates is polished at a polishing station, and polishing stops when an endpoint criterion is detected using the endpoint algorithm.

Polishing pad with partially recessed window

A polishing pad has an opaque polishing layer with an aperture therethrough and a polishing surface, and a solid light-transmissive window in the aperture. The solid light-transmissive window includes an outer portion secured to the polishing layer and an inner portion secured to the outer portion. The outer portion has a upper surface recessed relative to the polishing surface, whereas the inner portion has an upper surface that is substantially co-planar with the polishing surface.

Eddy current sensor with enhanced edge resolution

An apparatus for monitoring the thickness of a conductive layer on a substrate includes a support to hold a substrate having a conductive layer, an eddy current monitoring system including a first plurality of core portions, and a motor to cause relative motion between the support and the eddy current monitoring system such that the substrate moves across the first plurality of core portions in a direction that defines a first axis. At least one core portion is positioned further from a second axis than at least two other core portions. The second axis is orthogonal to the first axis.

Polishing system with in-line and in-situ metrology

A computer-implemented method for process control in chemical mechanical polishing in which an initial pre-polishing thickness of a substrate is measured at a metrology station, a parameter of an endpoint algorithm is determined from the initial thickness of the substrate, a substrates is polished at a polishing station, and polishing stops when an endpoint criterion is detected using the endpoint algorithm.

Using spectra to determine polishing endpoints

Methods of determining a polishing endpoint are described using spectra obtained during a polishing sequence. In particular, techniques for using only desired spectra, faster searching methods and more robust rate determination methods are described.

Spectrographic monitoring of a substrate during processing using index values

Methods, systems, and apparatus for spectrographic monitoring of a substrate during chemical mechanical polishing are described. In one aspect, a computer-implemented method includes storing a library having a plurality of reference spectra, each reference spectrum of the plurality of reference spectra having a stored associated index value, measuring a sequence of spectra in-situ during polishing to obtain measured spectra, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum to generate a sequence of best matching reference spectra, determining the associated index value for each best matching spectrum from the sequence of best matching reference spectra to generate a sequence of index values, fitting a linear function to the sequence of index values, and halting the polishing either when the linear function matches or exceeds a target index or when the associated index value from the determining step matches or exceeds the target index.

Substrate features for inductive monitoring of conductive trench depth

A substrate for use in fabrication of an integrated circuit has a layer with a plurality of conductive interconnects. The substrate includes a semiconductor body, a dielectric layer disposed over the semiconductor body, a plurality of conductive lines of a conductive material disposed in first trenches in the dielectric layer to provide the conductive interconnects, and a closed conductive loop structure of the conductive material disposed in second trenches in the dielectric layer. The closed conductive loop is not electrically connected to any of the conductive lines.

Determining physical property of substrate

Endpointing detection for chemical mechanical polishing based on spectrometry

A method of detecting a polishing endpoint includes storing a plurality of library spectra, measuring a sequence of spectra from the substrate in-situ during polishing, and for each measured spectrum of the sequence of spectra, finding a best matching library spectrum from the plurality of library spectra to generate a sequence of best matching library spectra. Each library spectrum has a stored associated value representing a degree of progress through a polishing process, and the stored associated value for the best matching library spectrum is determined for each best matching library spectrum to generate a sequence of values representing a progression of polishing of the substrate. The sequence of values is compared to a target value, and a polishing endpoint is triggered when the sequence of values reaches the target value.