CHEMICAL MECHANICAL POLISHING APPARATUS
The present invention refers to chemical mechanical polishing device relates to, chemical sunscreen pad polishing liquid during mechanical polishing process according to abrasion amount on the consideration of the thickness of the polishing pad thickness of wafer permitting an accurate detection of for chemical mechanical polishing relates to device. Chemical mechanical polishing generally (Chemical Mechanical Polishing; CMP) process a rotating polishing plate on and in contact with the is a substrate, e.g. a mechanical polishing of the rotating the often performance is carried out a predetermined thickness of the substrate in such a way to flattening surface is a process. To this end, also 1 chemical mechanical polishing as shown in device (1) the polishing plate (12) a polishing pad (11) state clad thereon while magnetron, carrier head (20) the wafer with a polishing pad (W) (11) rotating while being applied with a pressure, on the surface of, a surface of wafer (W) is polished. To this end, polishing pad (11) a constant internal diameter, so the surface of rotation such that they remain (30r) while modifying a conditioner (30) is provided with a, polishing pad (11) is polished to make the chemical on the surface of a slurry is slurry supply line (40) is supplied through the.. At this time, carrier head (20) has door 3 as shown in, base driven in rotation (22 ') including a body portion (22) and a, base (22') between wall of a pressure chamber (C) includes the steps of: positioning a base (22') fixed to a membrane (21) and, membrane (21) on the bottom plate in a retainer ring wrapped around the (23) is comprised of, membrane bottom plate bottom wafer (W) (C) pressure chamber or thickness variation is measured by position to control the pressure of the fluid the wafer while (W) a polishing pad (11) while urged toward the. rotating the. Wherein, retainer ring (23) the wafer (W) is carrier head (20) out of to prevent to one surface of the substrate, and bottom of the polishing pad (11) to and in contact with the under pressure for is held. On the other hand, by a CMP process polishing a wafer (W) film thickness of. and must be conditioned the precise, and. To this end, a disclosure Public Patent Notification number 2001-93678 25th which call or the like according to the techniques of the existing method, polishing plate (10) and the polishing pad is (11) forming a transparent window to penetration (10a) a wafer (W) located in the region (20a) having the underside of, when layer layer for polishing wafer (W), such as copper of the conductive layers of adjacent to sensor coil with eddy current sensor (60) an alternating current by applying a eddy current sensor (60) from a wafer (Si) eddy current signal applying conductive layer, resistance component and reactance in conductive layer (So) output signal including a eddy current sensor (60) is detected by the, wherein the combined impedance conductive layer from variation amount detecting a change thickness the thickness used configuration of wet liquid to flow down. However, chemical mechanical polishing controlled conductive layer (W) as well as polished with, simultaneously polishing pad (11) since in similar to an in wear, amorphous c or CRF, polishing pad (11) in an amount such that the sap surface abrasion of error detection in thickness of conductive layer have had a problem that the of short. Therefore, of the polishing pad surface to accurately reflect a variation in thickness conductive layer thickness (W) wafer detecting the dB stores is the need for. In particular, polishing pad (11) of abrasion amount a chemical mechanical polishing process signal according to progress of the linear changes without since the flow sensor tube varies irregularly be gathered non-linearly, polishing pad (11) of abrasion amount (W) a wafer according to an error for detecting thickness of conductive layers of an had to the light source can result. The present invention refers to said connect the pads and for, chemical mechanical polishing process reflect abrasion amount pad polishing liquid during conductive layer of the wafer thickness to apply the phase current to in. The, the present invention refers to wafer polishing of end point of seat and the rear seat equally, wafer polishing thickness accurately control in. Furthermore, the present invention refers to chemical mechanical polishing device for carrier head retainer ring of assembly of a can be easily in. The present invention refers to such as that described above for a certain amount, self-propagating e if petal this wafer is pressed against the polishing pad while in contact with the wafer chemical mechanical polishing process for a carrier head as used is being performed, said rate of polishing during a polishing process chemical mechanical said contact of the plate surface of the wafer pressing the membrane contacts the edge region and not the bottom panel including; number 1 number 2 having with different height if only the chin, withif only the chin, this forming to the conductive material in the form of ring number 1 member and, said number 1 member the underside of said non-conductive member is laminate forming said polishing pad during chemical mechanical polishing process number 2 comprising a member which is contact, said membrane the periphery of the ring which are disposed in the form retainer ring; comprises: characterized by chemical mechanical polishing device provides carrier head of. As such, conductive member a are formed such that they have if only the chin,if only the chin, with number 1 number 2 number 1 member and, non-conductive member of the member number 1 number 2 located for inserting the retainer ring member according to is formed, while is urged to the polishing pad by a non-conductive particles made by the member number 2, number 1 number 2 attached to the surface of an object different if only the chin, withif only the chin, this conductive member formed in two 2 number 1 number 2 if only the chin, withif only the chin, a knowledge in advance of from the output signal of a number 1 number 2 if only the chin, withif only the chin, polishing pad to using height difference in case of a sudden brake, thickness variation is enabled. Therefore, wafer conductive layers of an eddy current in calculated from output signal of the wafer of the variation of the thickness of polishing pad a layer thickness conductive and reflect a, wafer considering abrasion amount of the polishing pad conductive layers of an accurately measure the thickness the may yield an a beneficial effect. At this time, said number 2 if only the chin, withif only the chin, each said number 1 by virtue of being formed predominantly of a flat surface horizontal, rotating eddy current in each retainer ring uniformly output signal if only the chin, material is obtained. Furthermore, said number 2 the height of a circumferentially if only the chin,if only the chin, with said number 1 throughout the maintained constant, and it is preferred that a. And, said number 2 if only the chin, withif only the chin, each said number 1 the center is configured in the shape of a ring allow fasteners of different lengths to be radially from by is fixed to the lower end of, each retainer ring rotating if only the chin, in eddy current output signal may yield an uniformly. On the other hand, said number 1 member is formed of a metal material, a resin member said number 2, includes a storage location of any one or more plastic can be formed. The, number 2 is applying the current, the current conductive plate in an opposite direction of the eddy currents from arising in in the absence of metallic materials by the formation of a number 1, number 1 number 2 if only the chin, withif only the chin, eddy current in may yield an output signal. While, the present invention refers to, self-propagating e if petal this wafer is pressed against the polishing pad while in contact with the wafer chemical mechanical polishing process for device as chemical mechanical polishing is being performed, a polishing pad is said upper lines the trench and, said polishing pad through in the spots forming at pressure 1.5-20 lbs. polishing with a transparent window; of a carrier head and; applying said window so that eddy currents, is for receiving the output signal eddy current applied, said number 2 in said wafer and said number 1 if only the chin, withif only the chin, an outputting sensor; characterized by includes is composed of provides chemical mechanical polishing device. Wherein, said sensors is disposed one or more 3, said number 2 if only the chin, withif only the chin, in said wafer and said number 1. for respectively receiving the output signal. Invention as described above wherein or more, the present invention refers to, chemical mechanical polishing controlled to the opposite direction the sealant disposed retainer ring of a carrier head being applied with a pressure, is driven by the first power, conductive member a are formed such that they have if only the chin,if only the chin, with number 1 number 2 number 1 member and, non-conductive member formed in a layered manner on the underside of member number 1 number 2 retainer ring member according to is formed, while is urged to the polishing pad by a non-conductive particles achieved by member number 2 can smoothly flow through under pressure for capable of keeping a, different if only the chin, with attached to the surface of an object, and is formed as elastic conductive member if only the chin, this number 1 number 2 number 1 number 2 2 according to two if only the chin, withif only the chin, in a knowledge in advance of from the output signal of a number 1 number 2 if only the chin, withif only the chin, height difference of the variation of the thickness of polishing pad to using a real is enabled. The, the present invention refers to, wafer conductive layers of an eddy current in calculated from output signal retainer ring a layer thickness conductive of the wafer if only the chin, eddy current in a polishing pad obtained from an output signal of the variation of the thickness of and reflect a, wafer considering abrasion amount of the polishing pad conductive layers of an accurately measure the thickness the may yield an a beneficial effect. Chemical mechanical polishing of the existing method also Figure 1 shows a configuration of device shown in the elevational view, Figure 2 shows a plane view, Figure 3 also anti-section of head on belt conveyor 1, Figure 4 of the present invention according to one embodiment of carrier head of anti-section chemical mechanical polishing device, Figure 5 of Figure 4 of magnification of portion 'A' configuration for detecting the thickness for detectiong Image plane shown in the drawing, according to Figure 6 of the present invention other embodiment form shown in the some of carrier head is surface of Figure 1. Hereinafter, reference to accompanying drawing according to one embodiment of the present invention chemical mechanical polishing device (100) and a carrier head (120). disclosed above. Just, describes in the present invention, publicly known functional or configuration the description is for subject matter of invention speaks out a to omitted. Chemical mechanical polishing device (100) according to one embodiment of the present invention the, wafer (W) a polish face of polishing pad arranged and provided between polished (11) layer is overlaid a polishing plate (10) and, wafer (W) located to the opposite direction (W) a magnetron the semiconductor wafer urged into a carrier head (120) and a, wafer (W) conductive layer thickness to sense eddy currents the conduction from the eddy current sensor an outputting (130) and a, eddy current sensor (130) for application of an alternating current eddy current sensor (130) received from an output signal wafer (W) and an idle conductive layers of an a control unit (140) consists of to. Said polishing plate (10) a polishing pad top (11), in which state the fitting projection layer is overlaid is actuated in rotation at. Polishing plate (10) also the 1 and 2 as shown in eddy current signal is applied of a through-hole (10a) but may be included is, eddy current sensor (130) signals from conductive passing through the are arranged so that a through hole if (10a) may-element is free from. I.e., eddy current sensor (130) is pressed against the polishing pad (11) surface located only at the inferior side of, eddy current sensor (130) the polishing plate (10) are provided to embedded in a may be constructed so as to allow. Said carrier head (120) has door 4 as shown in, a base driven reciprocating motion of an actuator unit (122 ') including a body portion (122) and a, base (122') between wall of a pressure chamber (C) includes the steps of: positioning a base (122') fixed to a membrane (121) and, membrane (121) on the bottom plate in a retainer ring wrapped around the (123) consists of in. Wherein, membrane (121) and the base (122') a pressure chamber formed therebetween (C) the membrane from the ring inserted into the groove of the lamp a plurality flaps to form a a pressure chamber is divided into. And, pressure chamber (C) and is energized to apply each pneumatic pressure (C) pressure chamber is arranged, pressure chamber (C) bottom panel membrane while they are being fed is co-the freight downward, membrane bottom plate to enter the wafer (W) a polishing pad (11) urged toward the a. Simultaneously, body portion (122) by changing the shape of a yoke membrane (121) which the drive pipe rotates as well, thus membrane (121) water bottom of a wafer (W) while the drive pipe rotates as well consisting of chemical mechanical polishing process. And, retainer ring (123) (W) a wafer under a chemical mechanical polishing process of a ring is formed in the shape of wrapped around the, bottom chemical mechanical rate of polishing during a polishing process (123s) the polishing pad (11) remains of the under pressure for to. The, retainer ring (123) a polishing pad (11) placed on the a bottom (123s) for including number 2 member (1232) has wear can be made is made from consumable material. I.e., retainer ring (123) a polishing pad (11) touch the number 2 member (1232) and a, member number 2 (1232) stacked on the upper side of the number 1 member (1231) 14.. Number 1 member (1231) and a number 2 member (1232) a interface number 1 if only the chin, different heights (123s1) and number 2 if only the chin, (123s2) is formed. At this time, number 1 member (1231), for instance, point metal, e.g. conductive material eddy currents from arising in is formed is temperature to be generated. And, for example member number 2, plastic or resin, etc. is formed on property under a melting temperature of eddy current sensor (131,132) from the input signal applied to gas conduit that are traversed by a number 1 member (1231) generate the eddy currents from arising in in. At this time, number 1 if only the chin, (123s1) and number 2 if only the chin, (123s2) a flat surface and horizontally, membrane (121) of the center of the length along the and are differently curved in is formed, sputtered atoms distribute in whereby the ring shaped. The, if only the chin, number 1 (123s1) generate eddy currents at the eddy current sensor number 1 (131) and a, number 2 if only the chin, (123s2) generate eddy currents at the eddy current sensor number 2 (132) the retainer ring (123) is chemical mechanical even rotation is allowed to occur between the process water continuously delivered to the rate of polishing during a polishing process, a constant eddy currents each if only the chin, (123s1,123s2) can be produces, retainer ring (123) each if only the chin, (123s1,123s2) in eddy current output signal (So1, So2) may yield an uniformly. Furthermore, retainer ring (123) of number 1 if only the chin, (123s1) and number 2 if only the chin, (123s2) of the height of over the entire circumferential has (y) a channel region is defined between the, circumferential direction eddy current output signal from any location (So1, So2) the carrier so as to mount the signal. can be easily obtained. And, as shown in drawing number 1 if only the chin, (123s1) and number 2 if only the chin, (123s2) each is formed whereby the ring shaped, membrane bottom piece allow fasteners of different lengths to be radially from is distributed. One embodiment of the present invention said groove, and at least one: an carrier head (120) the, retainer ring (123) number 1 member the conductive particles (1231) and conductive the number 2 member (1232) if only the chin, of different heights each other (123s1,123s2) is formed, eddy current sensor (131,132) from the input signal applied to number 2 member (Si1, Si2) by (1232) each if only the chin, (123s1,123s2) is induced eddy currents from arising in in, if only the chin, (123s1,123s2) in outer periphery of the output signal (So1, So2; for example, wherein the combined impedance or resonant frequency) a eddy current sensor (131,888000 0757888) is enabled received at. At this time, each if only the chin, (123s1,123s2) height of between deviation (y) since in similar to an in the known, different if only the chin, (123s1,123s2) (So1, So2) in output signal obtained by receiving in real time a different 2 (So1, So2) from signal loops, , pad polishing liquid during chemical mechanical polishing process (11) according to the amount of degradation thickness wear of first and second insulating films are removed allow real-time detection are obtained. As well as is, one embodiment of the present invention said groove, and at least one: an carrier head (120) the, retainer ring (123) is number 1 member (1231) and a number 2 member (1232) the laminate two an approach each other to be minimal by forming the, the motor chamber receives a motor for unit for assembling the same may yield an also a beneficial effect. While, as shown in 6 also, according to other embodiment of the present invention, number 1 member (1231 ') and a number 2 member (1232') either the other ring-shaped groove in the form protrusion ring concave groove of a water magnetizing if only the chin, this may be formed. Even with is, number 1 member (1231 ') and a number 2 member (1232') for securing accurate position at both sides of assembly are obtained. Said eddy current sensor (130) the n burn wound hollow of the helix shaped sensor coil (not shown) is equipped with a control unit (140) for rising an alternating current from an, input signals from sensor coil (Si1, Si2, Si3; Si) by decreased from a magnetic flux a, conductor applies eddy currents, of electric conductors the distance between an conductor or thickness variable when varied, conductive article removal, an outer periphery of the wherein the combined impedance or the resonance frequency by an output signal (So1, So2, So3; So) to receive output signal or variation in the thickness of the conductor from a change made during the period (So) conductor is used to detect the distance. According to one embodiment of the present invention, eddy current sensor (130) the, retainer ring (123) of number 1 if only the chin, (123s1) eddy currents at the receiving (So1) generates and outputs signal number 1 eddy current sensor (131) and a, retainer ring (123) of number 2 if only the chin, (123s2) eddy currents at the receiving (So2) generates and outputs signal number 2 eddy current sensor (132) and a, wafer (W) of the conductive layers of eddy currents generates and outputs signal receiving (So3) number 3 eddy current sensor (133) 14.. Drawing 3 the two eddy current sensor (131, 132, 133; 130) is is provided to but, at 3 and receiving signal eddy current sensor can be. may be. Said control unit (140) a chemical mechanical polishing process is performed during the exertion to eddy current sensor (130) an alternating current by applying a radiofrequency current through the sensor coil while flow, if only the chin, number 1 (123s1) and number 2 if only the chin, (123s2) and wafer (W) generate eddy currents in conductive layers of an. And, control unit (140) each eddy current sensor (131, 132, 133; 130) which is detected in the number 1 if only the chin, (123s1) and number 2 if only the chin, (123s2) and wafer (W) (So) from output signals from conductive layers of an, eddy current sensor (131,132) from if only the chin, number 1 (123s1) and number 2 if only the chin, (123s2) wafer (W) of a distance and a sensing of a variation in the thickness conductive layer. Such call and Public Patent Notification number 2001-93678 25th which the sensing principle disclosure number 2002-31079 call can be a structure that the main data. Groove, and at least one said chemical mechanical polishing device (100) according to one embodiment of the present invention the, controlled chemical mechanical polishing the sealant disposed to the opposite direction a carrier head being applied with a pressure, (120) retainer ring of (123) is driven by the first power, conductive member if only the chin, number 1 (123s1) and number 2 if only the chin, (123s2) number 1 member a are formed such that they have a (1231) and a, non-conductive member number 1 member (1231) formed in a layered manner on the underside of member number 2 (1232) to retainer ring (123) according to port of one of the, polishing pad (11) while in contact with the non-conductive the number 2 member made by the (1232) 888000032288 8, eddy current sensor number 1 (131) and number 2 eddy current sensor (132) from the input signal applied to number 1 member supported to the front surface side (Si) (1231) of number 1 if only the chin, (123s1) and number 2 if only the chin, (123s2) 2 from signal loops, knowledge in advance of and a (So1, So2) if only the chin, a number 1 (123s1) and number 2 if only the chin, (123s2) (y) height difference of a polishing pad to modifier (11) thickness of copy are formed capable of measuring real time, eddy current sensor number 3 (133) (W) wafer by conductive layers of an eddy current in a wafer (W) (888000053188 8) output signal calculated from conductive a layer thickness retainer ring (123) if only the chin, of (123s1,123s2) in eddy current output signal (So1, So2) a polishing pad obtained from (11) and reflect a of the variation of the thickness of, polishing pad (11) and a power abrasion amount of conductive layers of an wafer (W) permitting an accurate detection of thickness a may yield an a beneficial effect. Said groove, and at least one chemical mechanical polishing according to one embodiment of the present invention during processing, the wafer conductive layer thickness detecting the method, first, wafer (W) a carrier head (120) the sealant disposed membrane the light guiding plate, polishing plate (10) of carrier head while magnetron (120) and self-propagating e together also, carrier head (120) (C) pressure chambers, which wafer (W) by applying hydrostatic pressure to a polish face of polishing pad (11) regardless of the state of the such that the air is pressed to, wafer (W) is chemical-mechanical polishing process for polishing surface of, the portable telephone sends. Furthermore, during a chemical mechanical polishing, eddy current sensor number 1 (131) and a number 2 eddy current sensor (132) is to apply the RF AC current to, eddy current sensor number 1 (131) and a number 2 eddy current sensor (132) formed of conductive material from retainer ring (123) of number 1 if only the chin, (123s1) and number 2 if only the chin, (123s2) to to the eddy occurs applies a (Si) input signal in the form of. At this time, carrier head (120) retainer ring of (123) of number 2 member (1232) the plastic, resin, etc. is protruded from the guide material property under a melting temperature of, eddy current sensor number 1 (131) and a number 2 eddy current sensor (132) by magnetic flux applied from eddy currents from arising in beam according to Image information. Instead, number 2 member (1232) the magnetic flux (magnetic flux) through the number 1 member (1231) of number 1 if only the chin, (123s1) and number 2 if only the chin, (123s2) eddy in is occurs. Furthermore, chemical mechanical polishing a cleaning process (W) is pressed against the polishing pad (11) is urged to the but in a polishing process of the available installation space by integrating, wafer (W) chemical mechanical polishing process for polishing liquid during pad (11) is gradually thinner, amorphous c or CRF wear is a second reference temperature. Therefore, eddy current sensor number 1 (131) and number 2 eddy current sensor (132) in if only the chin, number 1 (123s1) and number 2 if only the chin, (123s2) resonant frequency from an eddy current generated in resistance or reactance component and including an output signal wherein the combined impedance (So1, So2) to eddy current sensor (131,132) is received, control unit (140) received output signal (So1, So2) receives the polishing pad (11) according to number 1 wear of if only the chin, (123s1) and number 2 if only the chin, (123s2) rate of movement of output signal (So1, So2). calculated from the generated. At this time, number 1 if only the chin, (123s1) and number 2 if only the chin, (123s2) since in similar to an in the height of of knowledge in advance of the (y), the received output signals in real time from (So1, So2) polishing pad (11) may detect and storing an optimum position value of. Furthermore, number 3 eddy current sensor (133) (Si3) wafer from input signal to (W) by decreased from a magnetic flux a, wafer (W) of the conductive layers of generate eddy currents. And, number 3 as well as eddy current sensor (133) according to process polishing conductive layer thickness variation output signal reflected (So3): this recorder receives. I.e., eddy current sensor number 3 (133) (So3) signal there are outputs to be received in a resonant frequency or may be wherein the combined impedance, is by the conductive layer with a may detect of a variation in the thickness. At this time, eddy current sensor number 3 (133) (So3) the received output signals in (W) variation in the thickness of the wafer by a detection although it is possible, excitation the polishing pad (11) by summing variation in the thickness of the of wet liquid to flow down including error. Therefore, step 3 a polishing pad derived from authentic (11) thickness variation of a eddy current sensor number 3 (133) detected wafer (W) in thickness by reflecting conductive layer, conductive layers of an wafer (W) calculates an thickness. As said, the present invention refers to, carrier head (120) retainer ring of (123) the conductive of number 1 member (1231) and conductive of number 2 member (1232) is obtained by, number 1 member (1231) and a number 2 member (1232) if only the chin, of different heights each other the interface (123s1,123s2) are provided for electrically coupling the, if only the chin, of different 2 (123s1,123s2) the eddy current derived from output signal (So1, So2) from polishing pad (11) thickness variation of is calculated, wafer (W) derived from conductive layer thickness conductive layers of an output signal the eddy current calculated on the value calculated from the generated (So3) a polishing pad (8880000 913888) thickness variation of by differencing a signal reflecting plate, pad polishing liquid during chemical mechanical polishing process (11) considering abrasion amount of wafer conductive layers of an accurately measure the thickness the may yield an a beneficial effect. Above a preferred embodiment of the present invention thereby, the cold air flows but described illustratively, induced by such a specific range of the present invention in the embodiment are not limited only, claim a category is appropriately changeable is formed inside the tie.. ** Description of the sign for major part ** of the drawings 10: polishing plate 11: polishing pad 120: carrier head 121: membrane 122: body portion 123: retainer ring 123s1: if only the chin, 123s2 number 1 : if only the chin, number 2 130: eddy current sensor 140: control unit The present invention relates to a chemical mechanical polishing apparatus and a carrier head used therein. The carrier head is used in a chemical mechanical polishing process performed on a wafer while a plate surface of the wafer touches a rotating polishing pad. The carrier head comprises: a membrane including a membrane bottom plate touching and pressurizing the plate surface of the wafer during the chemical mechanical polishing process; and a retainer ring which arranged in a ring shape round the membrane, and includes a first member made of a conductive material and formed with a first stepped surface and a second stepped surface having different height, a second member touching the polishing pad during the chemical mechanical polishing process, and stacked on a lower part of the first member with a non-conductive member. The chemical mechanical polishing apparatus can precisely measure the thickness of a conductive layer of a wafer in consideration of an abrasion loss amount of a polishing pad by measuring a thickness changed amount of the polishing pad using a height difference, which is informed in advance, between a first stepped surface and a second stepped surface from two output signals of the first stepped surface and the second stepped surface, and then reflecting the thickness changed amount of the polishing pad to the thickness of the conductive layer, calculated from an eddy current output signal of the conductive layer of the wafer. if petal this wafer is pressed against the polishing pad while in contact with the self-propagating e said wafer chemical mechanical polishing process for device as chemical mechanical polishing is being performed, a polishing pad is said upper lines the trench and, said polishing pad through in the spots forming at pressure 1.5-20 lbs. polishing with a transparent window; said chemical mechanical rate of polishing during a polishing process to perform massaging easily to enter the wafer is pressed against the polishing pad self-propagating e the contact a wafer a carrier head and; applying said window so that eddy currents, applied eddy current sensing sensor output signal; comprising a, said carrier head a, said rate of polishing during a polishing process chemical mechanical said wafer membrane pressing the contact of the plate surface of the bottom panel contacts the edge region and not the having; number 1 number 2 having with different height if only the chin, withif only the chin, this forming to the conductive material in the form of ring number 1 member and, said number 1 member the underside of said non-conductive member is laminate forming said polishing pad during chemical mechanical polishing process number 2 comprising a member which is contact, said membrane the periphery of the ring which are disposed in the form retainer ring; having ; said sensor in said number 1 number 2 if only the chin, stepped surface and said output signal from said number 2 (So2) and obtaining throughput information thickness variations of the polishing pad, said sensor output signal from the wafer polishing said tank is reduced in volume (So3) number 3, from an output signal said number 3 said polishing pad the reflect the information of the variation of the thickness of said wafer polishing layer the control unit gauge; comprising a, said said number 2 said number 1 the amount of the polishing pad thickness variations if only the chin, withif only the chin,if only the chin, with said number 1 in the ouput signal said number 2 received from said number 2 using predetermined height difference if only the chin, said number 2 member wear amount to that are calculated except that the characterized by chemical mechanical polishing device. According to Claim 1, said number 2 if only the chin, withif only the chin, each said number 1 horizontal characterized by a flat surface and in which form the chemical mechanical polishing device. According to Claim 1, said number 2 the height of said number 1 if only the chin, withif only the chin, over the entire a circumferentially remains characterized by chemical mechanical polishing device. According to Claim 1, said number 2 is configured in the shape of a ring each said number 1 if only the chin, withif only the chin, the center radially from is fixed to the lower end of to allow fasteners of different lengths to be characterized by chemical mechanical polishing device. According to Claim 1, said number 1 member is formed of a metal material, a resin member said number 2, any one or more plastic includes a storage location of of the link is characterized by chemical mechanical polishing device. According to Claim 1, said sensors is disposed one or more 3, said wafer and said number 1 denote the respective output signals in said number 2 if only the chin, withif only the chin, characterized by receiving a chemical mechanical polishing device. Deleted Deleted
