Wire welding tech. for copper metallized integrated circuit
Technical Field The invention relates generally to the field of semiconductor device and, more specifically relates to welded to copper-metallized integrated circuits (bond) wire bonding process. Background Art For over forty years, in the integrated circuit (IC) technology, pure or doped aluminum has become metallized selected interconnection and the weld. The major advantage of the aluminum to facilitate deposition and to form a pattern. Furthermore, the gold, copper or aluminum wire is welded to the aluminum weld zone has been developed to a high degree of automation technology, the level of miniaturization and reliability. # 5,455,195 the authorized 3 October 1995, (Ramsey and others, "used in the integrated circuit conductive welding in method of metallurgical stability"); # 5,244,140 authorized 14 September 1993, (Ramsey and others, "more than 125kHz the ultrasonic welding process of the"); # 5,201,454 authorized 13 April 1993, (Alfaro, and others, "IC interconnect enhanced metallization growth process"); # 5,023,597 authorized and 11 June 1991, (Tsumura, " has the semiconductor device of the copper wire ball bonding) can be found in U.S. patents high technical standards examples of aluminum wire bonding. The continuous trend of miniaturization in the IC, the interconnection between active circuit elements increasingly dominates the time constant RC achievable IC speed-power product. As a result, relatively high resistivity of the interconnecting aluminum now look since the low resistivity such as copper, and the like of the metal is poor. Furthermore, aluminum to electromigration is becoming a prominent of the sensitivity of a serious obstacle. As a result, according to the relatively high conductivity of copper electromigration of the low sensitivity, now in the semiconductor industry, there is a the copper is used as a better interconnect material of strong. However, from the mature aluminum interconnection technology point of view, to the copper this change is one of the major technical challenges. The copper must be protected, in order to prevent the IC proliferates into of the silicon substrate material, in order to protect the circuit against the copper atoms of the silicon lattice of the carriers in the service life of the impact of the destructive characteristics. The pads made of copper, must be prevented during the manufacturing process flow of forming a thin copper (I) film, this is because these film seriously hamper the reliable welding of welding wire, especially for conventional gold wire ball bonding. Metal with the alumina film of aluminum on the contrary, through hot pressing, and in the course of welding together with ultrasonic energy, is covered on the metal copper on the copper oxide film is not easy to be broken. As further difficulty, bare copper weld zone is easy to be corroded. In order to overcome these problems, has disclosed the copper pads on the clean a layer of aluminum on the process, therefore, should be reconstructed by the conventional gold ball bonding, weld on the traditional situation of the aluminum pads. # 5,785,236 the authorized 28 July 1998 in the United States Patent (Cheung and others, "with existing IC wire bonding technology compatible advanced copper interconnect system") describes a suitable welding process. However, the scheme has several shortcomings. First of all, the manufacturing cost of the aluminum-high than expected, this is because the process needs to deposit metal, to form a pattern, an additional step of etching and cleaning. Secondly, such a cover must be sufficiently thick, in order to prevent the copper through the cover metal and the diffuser and pollution IC transistor. 3rd, cover the used aluminum is soft, so that it will be subject to the electrical test probe contacts in a plurality of traces of serious damage (marking). Furthermore, the size of the damage has been on the weld zone becomes particularly obvious in the hour, so that the subsequent ball bonding welding is no longer reliably. # 60/183 the submitted 18 February 2000, 405, has been disclosed in U.S. Patent application for covering the copper metallization of copper pads of IC the low-cost structure and method. Related to the application of this invention. An urgent need to provide a kind of a wire welded to the covered reliable method of the pads, the method of the manufacturing cost and the greatest extent that might impede the subsequent wire bonding to the metal of the combined control phase diffusion. This welding method should be flexible enough, to be suitable for different IC products clan's and a wide range of the design and process variations. Preferably the shortening the production cycle time and increase the yield of these innovative at the same time, without the need for expensive additional manufacturing equipment. Content of the invention One aspect of the present invention can be applied to reduce the area of the bonding area of the chip IC is reduced then support. As a result, the invention help to alleviate such as cellular communication, pager, hard disk drive, a laptop computer and medical instruments the application of the shrinking the space constraint. Another aspect of the present invention is by means of electroless deposition to be self-limiting process for manufacturing the bonding area (self-defining) metal cover, thus avoiding high-cost lithographic and alignment process. A further aspect of the invention is the guidance of the diffusion coefficient by the metal, selection of appropriate metal to and adjustment of the layer thickness (coordinate), the welding temperature rises to the upper diffuser and of subsequently prevent welding to minimize chemical reaction. Another aspect of the invention is that through the elimination of probe marks difficult problem of welding (mark) and subsequently to advance the wafer level multi-probe detection process and reliability. Another of the present invention aims to provide a flexible design and technological concept, thus they can be applied in many semiconductor product group, and these design and technological concept is universal, thus can be applied to the product of several generations. The invention also has a purpose is to only use the IC device manufacturing the most frequently used and accepted design and process, thus avoiding the use of the new capital investment and the manufacturing equipment has been installed. The present invention discloses a firm, reliable and low cost of the metal structure and process, the metal structure and process enabling integrated circuit (IC) interconnect copper metallization is electrically connected to the metal wire. The structure includes a deposit on the surface of the copper oxide-free to prevent copper diffusion barrier (barrier) a layer of metal, the thickness thereof so that it can be deposited onto the 250 under [...] with the diffusion of copper compared with no barrier metal layer is less than 80%. The structure also includes in the 250 [...] diffusion of the barrier metal layer under the weld metal does not exist when the reduction can be compared with more than 80% of the most outer layer. And located in the structure also includes states the nonoxidation copper between with the barrier metal layer is a thin seed metal layer; wherein the seed metal is palladium or tin. Finally, a metal wire is welded to the outermost layer for metallurgical connection. From nickel, cobalt, chromium, molybdenum, titanium, tungsten and their alloy selected from the group consisting of this kind of barrier metal layer. From the gold, platinum and silver selected from the group consisting of the outermost metal layer. The present invention relates to a of the copper interconnect metallization of high-density high-speed IC, in particular to have a large number of metallized input/output or of those IC "bonding area". The such as processor, digital and analog device, logic device, high frequency and high power devices and the like and many device ethnic groups on a large area and small area obtained in chip class these circuit. And another aspect of the present invention is disclosed for the metal wire and is located in the with copper interconnect metallization between the pads on the integrated circuit to form a metallurgical connection method, comprises the following steps: in the welding area of the copper metallization is deposited on the surface of the seed metal layer, wherein the seed metal is palladium or tin; plates spreads through electroless deposition of a layer of barrier metal layer, the barrier metal layer has a sufficient thickness, so that the layer with the non-existent compared with the barrier metal layer, in the 250 to reduce the diffusion of copper under [...] more than 80% ; plating by electroless deposition of a layer of metal can be welded, the welding metal layer has a sufficient thickness, so that the layer and does not exist when the weld metal when compared, in the 250 under [...] the diffusion of the barrier metal layer is less than 80% ; and one of the metal wires welded to the outermost layer of metal. The by the present invention is suitable for the mass production of the selection criteria for the description of the process flow and these purposes have been achieved. The welding zone to be manufactured of copper is introduced into the surface of the seed crystal (seed) such as arrowhead of metal such as such as nickel and covered with a layer of barrier metal layer. The thickness of the barrier metal layer must be so, thus can prevent the excessive high temperature of the welding operation, the upper diffuser of copper. arrowhead or gold , such as the outermost layer of metal can be welded. The thickness of the layer must be so, so that it can prevent the diffusion of the nickel to the surface, the nickel on the surface to oxidize and hinder the welding. In the mass production, electroless plating to deposit the various metal layer, so as to avoid expensive the needs of the photoresist defining steps. Description of drawings From the following a preferred embodiment of this invention a detailed description of the attached drawing and the attached and in the right of the new features, the technical progress of this invention and its various aspects become apparent. Figure 1A and 1B shown a preferred embodiment of this invention a schematic profile diagram. Figure 1A shown located in an integrated circuit having copper metallization on the pads of the stacked layers of the cover can be welded. Figure 1B plan of the metal wire shown comprises a ball bonding 1A of the solder pads. Figure 2 is schematic sectional drawing of a preferred embodiment of the present invention more detailed. Figure 3 is schematic sectional drawing of a preferred embodiment of the present invention more detailed. Figure 4 according to the present invention is shown of producing a welded hiding diagram of the process flow. Annex: the table lists the spread on the lower-layer metal of the barrier metal layer does not exist is reduced compared with more than 80% of the required calculation thickness of the barrier metal. Mode of execution Figure 1A shown a preferred embodiment of this invention a schematic sectional diagram, the its entire expressed as 100. Integrated circuit (IC) having a copper interconnect metallization, and the penetration of the moisture protection of the outer coating 101 of the covering. In addition the coating is usually 0.5 to 1.0 the thick m is made of silicon nitride. A window in the outer coating 102, in order to expose the copper metallization 103 part of the. In Figure 1A not shown is buried in the copper and to prevent their diffusion into the lower layer of the various parts of the IC (usually by the tantalum nitride, tantalum silicon nitride, tungsten nitride, tungsten-silicon nitride, titanium, titanium nitride or titanium-tungsten; see Figure 3). In Figure 1A in, shown generally only part of the IC of the medium 104. The electrical insulating portion can include not only traditional such as silicon dioxide, plasma enhanced chemical vapor deposition of the medium, also includes such as siliceous hydrogen silicontime of half oxane (hydrogen silsesquioxane), organic polyimide, aerogel and poly-P-xylene with a quite low dielectric constant of the relatively new dielectric material or includes a plasma generating or ozone tetraethyl orthosilicate of the dielectric layer of the oxide of the stack. Because of these material no previous standard insulator so dense and relatively weak mechanically, so usually the copper the following medium to carry out reinforcement. # 60/085 the submitted 18 May 1998, 876, (Saran and others, "is used for reinforcing the semiconductor bonding area in the fine pitch system and method") submitted and 14 July 1998 # 60/092, 961, (Saran, "used for an active integrated circuit welding system and method") can be found in U.S. Patent application for the example. Because the copper susceptible to corrosion, even thin, copper (I) film is also difficult to weld, the present invention provides as shown in Figure 1, 2 and 3 shown in the cover exposed copper is formed on the structure and technique. According to the invention, the cover is composed of a stack of layer of metal, its thickness is adjusted to make the stacked satisfy three requirements: * Play on the copper cover to the cap against the surface of the spread (the water at this, copper might impede the subsequent wire bonding operation) the role of the barrier layer. In particular, the adjusting of the cover of the selection and thickness of the metal, so as to cover the 250 the lower copper [...] diffusion and does not exist on the barrier metal layer is reduced compared to more than 80%. * In order to avoid expensive lithography steps of the technology to manufacture the cover. In particular, the use of non-electrical the skill comes depositing the cover metal layer. * The cover has the most outer layer of the metal surface. Specifically, the wedge bonding using the conventional ball bonding ( bonding wedge) and in order to metallurgically a wire and other coupling member is connected to the weld zone. As shown in Figure 1B and 2 shown, the wire ball bonding is to use coupling component to produce a better method for electrical connection. Another method is to utilize the wedge-shaped soldering apparatus (bonder) the belt welds (ribbon bonding). Compared with the wedge bonding, ball bonding performed at a high temperature, is the need to coordinate the material of the present invention and process. A process for wire bonding of the bonding area by the IC chip and the chip will be welded to the object is arranged in a heating base and their temperature up to 170 and 300 the only between [...]. Through the heating capillary tube (where the temperature normally in 200 and 500 the within the range of between [...]) lay wire (string) 110 (Figure 1B in), the wire 110 is usually gold, gold-beryllium alloy, other gold alloy, copper, aluminum or its alloy, the diameter of the from the usually 18 to 33 the within the range of m. The tip of the wire, the use of flame or spark to the free air ( air free) ball. The diameter of the ball usually from about 1.2 to 1.6 the diameter of the wires. To the chip bonding area of the capillaries (Figure 1A of in 102) mobile, the ball is pressed on the pads metallization layer of the cover (Figure 1A and 1B layer 106) on. The combination of the compressive force with the ultrasonic energy generated is formed through a metal inter-diffusion of the firm metallurgical welding. During welding, the temperature range is usually from 150 to the 270 [...]. In Figure 1B in, the form of the representation 111 in the wire ball bonding as the "ball" of the examples of the final shape. To this invention, important is the recent technological development for wire bonding has been allowed to form a small and reliable spherical contact and wire loop can be strictly control the shape ( loop wire). Light can be realized 75 and 40 the distance between the ball between the m. For example, in the United States the Kulicke Grove Pa cantonal Willow & Soffa of computerized welder 8020 or Texas in the United States the Dallas, Texas SA ABACUS Instruments found in of these advances. Through the air in a predetermined way mobile computer control of the capillary tube is defined by the shape of the loop. Finally, capillary tube reaches its predetermined destination and the contact of the contacts the object in the weld zone. The trace through the capillary tube, forming a metallurgically of welding needle foot type (stitch bond), and the metal wire is burnt and release the capillary. Small and reliable contact needle foot type , the transverse dimension of the pin mark is about wire diameter (the exact shape and the capillary tube the shape of the relevant, such as the capillary pipe wall thickness of capillary engram (footprint) and) of 1.5 to 3 times. One advantage of this invention is to provide a hard enough to make the welding electrical multi-probe detection used in the fine tip of the needle does not produce the probe traces the surface of the metal cover. When the weld zone area small to such an extent-that at the same time trend-bonding area of the impression of the needle can be used to disrupt the majority of the welding region, by the needle impression tatters soft metal surface on the special difficult to weld. According to the invention by a two layer to provide the copper 103 with the metal cover on the: Layer 105 is a copper 203 is, sometimes metal layer deposited on the seed crystal (seed) (see Figure 2 and 3) the upper. Layer 105 example is nickel, cobalt, chromium, molybdenum, titanium, tungsten and alloys thereof. These metal nonferrous metal, and can be through an electroless plating to deposit the; however, their poor ability can be welded. In these metals, in the 250 under [...] , is smaller than the diffusion coefficient of copper 1 × 10E-23cm2/s. As a result, these metal into a good copper diffusion barrier layer. Calculate and obtain by diffusion of the diffusion of copper compared to the reduced presence of these layer is more than 80% of the required layer thickness. As an example, the annex listed in the table when the copper in the 250 [...] or 160 the temperature of [...] lower diffuser (diffusion time (min) as parameter) when the layer thickness of the nickel. Generally speaking, from 0.5 to 1.5 the thickness of the barrier layer to m can be safely meet the copper reduction criterion. Layer 106 is located in layer 105 as the outermost layer of the cover; it can be welded, so that it can accept the wire bond 111. Layer 106 examples are gold, platinum, palladium and silver. Furthermore, in the 250 under [...] , these metal with respect to the barrier layer 105 of the metal used in the diffusion coefficient (such as nickel) less than 1 × 10E-14cm2/s. As a result, these metal is layer 105 a good diffusion barrier layer material. Furthermore, the calculated and obtained from the diffusion layer 105 of the proliferation of the metal in the layer does not exist on the 106 compared with the reduction of more than 80% of the required layer thickness. As an example, the annex listed in the table when the nickel in the 250 [...] or 160 the when gold[...] spread on the layer thickness of the, , in order to spread the time (min) as parameter. Generally speaking, the 1.5 or m the most the thickness of the outer layer can be safely meet the layer 105 the reduction of the diffusion of the metal, standard. As another example, the annex listed in the table when the nickel in the 250 [...] or 160 the when arrowhead[...] spread on the layer thickness of the (µm), with diffusion time (min) as parameter. In general, about 0.4 to 1.5 the outermost m 106 will meet the thickness of the layer 105 the reduction of the diffusion of the metal, standard. Combining Figure 4 to describe the electroless plating process. Usually, the plated layer would be in line with the opening of the bonding area (Figure 1A of in 102) size. However, with the protection of reduced thickness for the purposes of bonding area of the outer coating, one or more of the plating layer may non-electrically growth beyond the periphery of an opening. Fig. 2 the schematic shows one example of the layer growth. Protective outer coating 201 have a reduced thickness 201a (for example, 0.5 the m and is not ordinarily of the 1.0 m). Directly plated on the copper metallization 203 from oxidation of surface 203a of the metal on the seed layer 208 easily within the openings in the outer coating, the barrier layer 205 and a weldable layer 206 over the periphery of the opening. In Figure 2 with 205a and 206a indicating this a cover area; the wire 211 "ball" has no effect on the metallurgical welding, but may affect the minimum distance between adjacent pads. Figure 3 the summarized in more detail a preferred embodiment of the invention; the majority of the size range in the picture sign row 1a and 1B, in fig. 4 discussed in electroless plating and other manufacturing process steps. Grade outer coating 301 limits the size of the bonding area of the opening, and the thickness of the cover sufficient to meet IC copper metallization pads 303 of all stack layer. copper pathline 303 embedded refractory metal shield 302 in (for example, tantalum nitride), the metal shield 302 is medium 304 and metal reinforced part 304a surrounded by; its method as mentioned above. To directly face the surface of the clean nonoxidation copper 303a of the 1st layer of the cover, that is, a thin seed metal layer 308 (for example, palladium, about 5 to 10 nm thick; another selected as the tin). Directly on the seed metal layer is on the diffusion of copper as a barrier metal layer 305 (for example, nickel). In this barrier layer as a barrier on the top of the diffusion on the barrier metal layer (such as nickel) and, at the same time as the welding of the metallurgy can be the outermost layer of the cover of the metal layer 306 (for example, gold or palladium). In Figure 4 used for making detailed in the fig. 3 process for the welding of the currentless hiding. In the protection of the weld zone in the outer coating is in the welding region is exposed after the copper IC metallization, the deposition process of the cover 401 is started; a process sequence is as follows: · Step 402: the use of spin-coating technique to the silicon IC is the backside of the wafer. This coating will prevent accidents on the back side of the wafer by the metal deposition. · Step 403: typically in the 110 to resist [...] confrontation time period is about 30 to 60 minutes of baking. · Step 404: the use of plasma ashing polishing (ashing) process on the exposed copper surface bonding area of about 2 minutes of cleaning. · Step 405: through the copper exposed bonding area of the wafer immersed in the sulfuric acid, nitric acid or any other acid in a solution of about 50 to 60 seconds to carry out cleaning. · Step 406. : In the overflow rinser for about 100 to 180 seconds. · Step 407: the wafers are immersed in the catalytic metal chloride (such as palladium chloride) solution of about 40 to 80 seconds, in order to "activate" the copper surface, a thin metal layer (such as arrowhead) the crystal deposited on the surface of the clean nonoxidation copper. · Step 408 : (dump) in the dump rinser for about 100 to 180 seconds. · Step 409: electroless plating against copper up-diffusion of the barrier metal layer. If selecting nickel-, is 150 to 180 seconds will deposit of plating between about 0.4 to 0.6 the m thick nickel. · Step 410 : in the dump rinser for about 100 to 180 seconds. · Step 411: electroless plating the outermost layer, the outermost layer can be welded and at the same time also provides preparedness on the barrier metal layer below the diffusion barrier layer. If gold or palladium, is 150 to 180 seconds will deposit the plated between about 0.4 to 0.6 the m thick gold or palladium. Better process the first to use a self-limiting surface metal replacement of the immersion step. If the gold, the 400 to 450 seconds between the deposition of plating is approximately 30 nm thick gold. As the 2nd step thicker metal layer (0.5 to 1.5 the m thick), the immersion step is automatic catalytic process steps. · Step 412 : in the dump rinser for about 100 to 180 seconds. · Step 413 : in about 8 to 12 minutes of the protection resist peeling off the back side of the wafer. · Step 414: rotating wash and drying for about 6 to 8 minutes. The manufacturing technique for the lid bonding area 415 stop. The above described process through the ball bonding or wedge bonding to metallurgy manner subsequently to connect the wires or strips. Because the barrier metal layer and the hardness of the outer layer is of a more rigid metal as the material of the metal cover, is soft aluminum material and, therefore, of the prior art compared with aluminum metal cover, in the welding step of the present invention with the probe before the electrical measurement states when the outermost layer of the bonding area, will leave substantially no trace of the probe. Although the to this invention the illustration made on the description of the embodiment, however, this description is not a limitation on the analysis. After the reference this specification, illustration embodiment of other embodiments of this invention and various modifications and combinations of the technical personnel in this field have become apparent. As an example, the invention can be applied to difficult or impossible to through a conventional ball bonding or wedge bonding apart from the welding technology of bonding area beyond copper IC metallization, such as high-melting metal and a noble metal alloy. As another example, the invention can be extended to batch processing, further reducing the manufacturing cost. As another example, the invention can be used for wire/with welding and solder interconnect hybrid technology. Therefore, the intention in the attached claims will cover any such modifications or embodiments. table The following metal of the upper diffuser to reduce more than 80% of the thickness of the barrier metal layer (micron) A robust, reliable and low-cost metal structure and process enabling electrical wire/ribbon connections to the interconnecting copper metallization of integrated circuits. The structure comprises a layer of barrier metal that resists copper diffusion, deposited on the non-oxidized copper surface in a thickness such that the barrier layer reduces the diffusion of copper at 250 DEG C by more than 80 % compared with the absence of the barrier metal. The structure further comprises an outermost bondable layer which reduces the diffusion of the barrier metal at 250 DEG C by more than 80 % compared with the absence of the bondable metal. Finally, a metal wire is bonded to the outermost layer for metallurgical connection. The barrier metal is selected from a group consisting of nickel, cobalt, chromium, molybdenum, titanium, tungsten, and alloys thereof. The outermost bondable metal layer is selected from a group consisting of gold, platinum, and silver. <IMAGE> 1. One kind is used for the metal wire and is located in the with copper interconnect metallization between the pads on the integrated circuit a metallurgical connection structure, comprising: The surface of the copper oxide-free bonding area; A layer of barrier metal layer, the barrier metal layer prevents the deposited on the copper surface of a copper-diffusion; Welding the outer layer of a metal; Welded to the most outer layer can be the welding metal of one of the metal wires, characterized in that So adjusting the barrier metal and its thickness, thus the layer and compared with the presence of the barrier metal, in the 250 to reduce the diffusion of copper under [...] more than 80%; While such that the thickness of the weld metal, so that the most outer layer and does not exist when the compared with metal can be welded, in the 250 under [...] the barrier to reduce the diffusion of the metal more than 80% ; and said structure further comprises: Located between states the nonoxidation copper with the barrier metal layer is a thin seed metal layer; Wherein the seed metal is palladium or tin. 2. Structure according to Claim 1, characterized in that from nickel, cobalt, chromium, molybdenum, titanium, tungsten and its alloy selected from the group consisting of the barrier metal layer. 3. Structure according to Claim 1, characterized in that the from gold , platinum, palladium and silver selected from the group consisting of the metal layer can be welded. 4. Structure according to Claim 1, characterized in that the from gold , copper, aluminum and its alloy selected from the group consisting of the metal wire. 5. One kind is used for the metal wire and is located in the with copper interconnect metallization between the pads on the integrated circuit to form a metallurgical connection method, comprises the following steps: In the welding area of the copper metallization is deposited on the surface of the seed metal layer, wherein the seed metal is palladium or tin; plates spreads through electroless deposition of a layer of barrier metal layer, the barrier metal layer has a sufficient thickness, so that the layer with the non-existent compared with the barrier metal layer, in the 250 to reduce the diffusion of copper under [...] more than 80%; Plating by electroless deposition of a layer of metal can be welded, the welding metal layer has a sufficient thickness, so that the layer and does not exist when the weld metal when compared, in the 250 under [...] the diffusion of the barrier metal layer is less than 80% ; and The one of the metal wires welded to the outermost layer of metal. 6. Method according to Claim 5, characterized in that comprises the steps of ball bonding or wedge bonding wire bonding. 7. Method according to Claim 5 or 6, characterized in that through the welding area formed by the following process, comprising: On said integrated circuit deposited on the surface of the protective outer coating, the outer coating comprises the surface portions having copper metallization; and By photoetching technique selected in the outer coating in the area of the opening, thereby exposing the copper metallized surface. 8. Method according to Claim 7, characterized by also including after the step in the opening, through the exposed copper surface immersed in the sulfuric acid, nitric acid or any other acid in solution of the cleaning step. 9. Method according to Claim 5, characterized in that said deposition seed crystal metal comprises the steps of immersing the bonding area in a catalytic metal chloride solution. 10. Method according to Claim 9, characterized in that the stated metal chloride is palladium chloride. 11. Method according to Claim 5, characterized in that the, electrolyze electroplating of the metal layer can be welded is dip coating. 12. Method according to Claim 11, characterized in that said electroless plating of the metal layer can be welded is dip coating, followed by auto-catalytic plating. 13. Method according to Claim 5, characterized in that before the welding step also comprises a probe for the outermost layer of the bonding area the electrical measurement states so as not to leave the step of the probe marks. Time (hours) platinum in copper 3 60 1440 4320 nickel of the copper 3 60 1440 4320 of palladium in the copper 3 60 1440 4320 of the nickel in gold 3 60 1440 4320 of the nickel in the palladium 3 60 1440 4320 250 (degrees) 4.68E -07 2.09E -06 1.03E -05 1.78E -05 5.39E -07 2.41E -06 1.18E -05 2.04E -05 1.30E -01 5.60E -01 2.75E + 00 4.76E + 00 9.10E -01 4.06E + 00 1.99E + 01 3.45E + 01 2.70E -02 1.22E -01 5.98E -01 1.04E + 00 160 (degrees) 1.79E -09 8.01E -0 3.93E -08 6.80E -08 2.16E -09 9.66E -09 4.73E -0 8.19E -0 9.00E -02 4.10E -01 2.00E + 00 3.46E + 00 1.10E -01 5.10E -01 2.51E + 00 4.35E + 00 8.00E -03 3.80E -02 1.85E -01 3.20E -01