Electrostatic chuck with mesa

Abstract

An electrostatic chuck (ESC) for a plasma processing chamber and a method of manufacturing the ESC are described. In an example, a substrate support assembly includes a ceramic top plate having a top surface with a processing region. One or more electrodes are in the ceramic top plate. A plurality of mesas are in the processing region and on the top surface of the ceramic plate or vertically above an edge of one of the one or more electrodes.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims the benefit of U.S. Patent Application No. 17 / 686,324, filed Mar. 3, 2022, which in turn claims the benefit of U.S. Provisional Patent Application No. 63 / 175,218, filed Apr. 15, 2021, the entire contents of which are incorporated herein by reference.

[0002] Embodiments of the present disclosure relate to the field of reactors or plasma processing chambers, and more particularly to electrostatic chucks with mesas.

Background Art

[0003] Processing systems, such as reactors or plasma reactors, are used to form devices on substrates such as semiconductor wafers or transparent substrates. Often, the substrate is held by a support for processing. The substrate can be held by the support by vacuum, gravity, electrostatic force, or other suitable techniques. During processing, a precursor gas or gas mixture in the chamber is energized (e.g., excited) into a plasma by applying power, such as radio - frequency (RF) power, from one or more power supplies coupled to the electrodes to the electrodes in the chamber. The excited gas or gas mixture reacts to form a layer of material on the surface of the substrate. The layer can be, for example, a passivation layer, a gate insulator, a buffer layer, and / or an etch - stop layer.

[0004] In the semiconductor and other industries, an electrostatic chuck (ESC) is used to hold a workpiece, such as a substrate, on a support during processing of the substrate. A typical ESC may include a base, an electrically insulating layer disposed on the base, and one or more electrodes embedded in the electrically insulating layer. The ESC may be provided with an embedded electrical heater and may be fluidly coupled to a source of heat transfer gas for controlling the substrate temperature during processing. In use, the ESC is fixed to a support in a process chamber. The electrodes in the ESC are electrically biased by an electrical voltage source with respect to a substrate disposed on the ESC. Opposite electrostatic charges accumulate in the electrodes of the ESC and on the surface of the substrate, and the insulating layer prevents the flow of charge therebetween. The electrostatic force resulting from the accumulation of the electrostatic charge holds the substrate to the ESC during processing of the substrate.

SUMMARY OF THE INVENTION

[0005] Embodiments of the present disclosure include an electrostatic chuck (ESC) for a plasma processing chamber and a method of manufacturing the ESC.

[0006] In an embodiment, a substrate support assembly includes a ceramic top plate having an upper surface with a processing region. One or more electrodes are within the ceramic top plate. A plurality of mesas are within the processing region, on the upper surface of the ceramic plate, or vertically above an edge of one of the one or more electrodes.

[0007] In an embodiment, a substrate support assembly includes a ceramic top plate having an upper surface with a processing region. The upper surface has one or more high topography regions. A plurality of mesas are within the processing region and on the upper surface of the ceramic plate. None of the plurality of mesas are on one or more high topography regions of the upper surface of the processing region.

[0008] In an embodiment, the substrate support assembly includes a ceramic top plate having an upper surface with a processing region. The upper surface has one or more high stress regions. A plurality of mesas are within the processing region and on the upper surface of the ceramic plate. None of the plurality of mesas are on one or more of the high stress regions of the upper surface of the processing region.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2A

Figure 2B

Figure 2C

Figure 3

Figure 4

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Figure 6

Modes for Carrying Out the Invention

[0010] An electrostatic chuck (ESC) for a plasma processing chamber and a method of manufacturing the ESC are described. In the following description, numerous specific details are set forth, such as electrostatic chuck components and material conditions, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that embodiments of the present disclosure may be practiced without these specific details. In other instances, well-known aspects, such as plasma enhanced chemical vapor deposition (PECVD) or plasma enhanced atomic layer deposition (PEALD) processes, are not described in detail so as not to obscure embodiments of the present disclosure unnecessarily. Moreover, it should be understood that the various embodiments shown in the figures are illustrative representations and are not necessarily drawn to scale.

[0011] One or more embodiments are directed to reducing surface stress in an electrostatic chuck (ESC) by mesa engineering, profiling, and ESC material design. Embodiments can include ESC mesa engineering and upper material structure design.

[0012] To provide context, mesas on the surface of an ESC can be used to support a workpiece when it is slightly lifted from the global top surface of the upper plate of the ESC. In an exemplary embodiment, the mesa coverage can be approximately 65% of the total surface area of the process surface, although it can be larger or smaller. The mesa can be approximately 15 microns in height, although it can be higher or lower. The mesa can be approximately 1 mm in diameter, although it can be larger or smaller. In past and current implementation forms, mesas are typically placed in many locations, including locations based on high stress regions on the surface of the ESC. Placement in such high stress areas can be accompanied by cracking on the top surface of the ESC due to thermal stress in the high stress and / or defect areas.

[0013] According to one or more embodiments of the present disclosure, mesa engineering and profile configuration of the top ESC material and design are implemented for surface stress reduction. The advantages of implementing one or more embodiments described herein can include a mesa-targeted location and an improved profile of the top surface of the ESC. The embodiments described herein can be implemented to enable the use of an ESC that has no cracking due to thermal shock to the top surface at temperatures higher than 500 degrees. The embodiments described herein can be implemented to remove or mitigate ESC thermal shock stress cracking.

[0014] The ESC surface can have a mesa manufactured on the top surface, for example, either by grinding or by bead blasting. Such a mesa can be described as continuous with the top surface of the ceramic top plate. The mesa can be formed within the ceramic surface or can be particles, such as diamond particles, added to the ceramic surface. FIG. 1 illustrates a plan view of the top surface of an electrostatic chuck (ESC) and a corresponding enlarged view 150.

[0015] Referring to FIG. 1, the top surface 102 of the ESC 100 includes an outer region 104 surrounding an inner region 106. The top surface 102 can be a ceramic surface, such as an aluminum nitride or aluminum oxide surface. The inner region 106 can include a processing region 107 having electrode wiring 108 therein, such as slightly below the surface of the ceramic. The electrode wiring 108 can be, for example, for the electrostatic electrodes of the ESC 100. The processing region 107 can also include a DC brazing joint location 110, such as slightly below the surface of the ceramic. A plurality of mesas 112 are manufactured on the surface of the processing region 107.

[0016] Referring again to FIG. 1, and in particular to the enlarged view 150, the plurality of mesa 112 includes not only mesas at a number of locations within the benign regions, but also mesa 112A in the region above the region of the DC brazing joint location 110. Mesa 112A in the region above the region of the DC brazing joint location 110 has been determined to be capable of placing mesa 112A in a high stress area.

[0017] FIG. 2A illustrates a cross-sectional view of an electrostatic chuck (ESC) including mesas at various locations, according to an embodiment of the present disclosure.

[0018] Referring to FIG. 2A, the ESC 200 includes a central zone 202, a main zone 204, a DC rod 206, and an ESC mesh 208. The DC rod 206 can be in a central location 210, as depicted. The ESC 200 also includes mesas, such as mesa 212A, 212B, 212C, and 212D. Mesa 212A is above the high voltage connection area 210, such as above the DC rod 206. Mesa 212B is above the electrode edge. Mesa 212C is in an area without an electrode. Mesa 212D is entirely above the electrode. Mesas 212A, 212B, 212C, and 212D are at a relatively shallow distance above the ESC mesh 208.

[0019] Referring again to FIG. 2A, the ESC surface can include a stress distribution including high stress regions and low stress regions on the top surface, based on its manufacturing features. Some high stress regions are created by the presence of high voltage electrodes approximately 1 mm below the top surface. For example, high stress can exist at (A) the boundary of the electrode edge of positive or negative polarity, (B) above the brazing connection, and / or at the edge of the ESC. According to embodiments of the present disclosure, the mesa structure is included above the low stress area, but not above the high stress area. For example, mesas 212A and 212B are in high stress locations, while mesas 212C and 212D are in low stress regions. In an embodiment, the mesa is included in location 212C and / or 212D, but not in location 212A or 212B.

[0020] In another aspect, the current ESC surface can have a profile after machining and / or polishing the upper surface. The profile can have bumps at the center of the ESC. The size of such a bump at the center can be about 10 - 20 microns, and a 15 - micron mesa follows the contour as illustrated in FIG. 2B described below. When the wafer is placed on the ESC, the wafer can have various contact points. The central bump can prevent the wafer from contacting the mesa in the immediate vicinity of the center. According to one or more embodiments of the present disclosure, the specification of the vertical amplitude (topographical feature) of the surface with respect to the horizontal distance for a given mesa height is determined. Heat transfer between the wafer and the ESC, and heat transfer from the plasma through the gas coupled to the ESC to the wafer can control the wafer temperature in the area. When only the central bump is polished, the wafer can result in a concave contact area where all mesas and heat transfer are uniform. In one embodiment, before the mesa is created, the flatness profile is measured on the surface of the ESC, and the mesa is not formed at locations where the vertical tilt (e.g., 15 microns / 10 mm) is not met.

[0021] FIG. 2B illustrates a cross - sectional view of another electrostatic chuck (ESC) including mesas at various locations, according to another embodiment of the present disclosure.

[0022] Referring to FIG. 2B, the support surface topography 250 can include a mesa profile 254 above the ceramic top surface profile 252. The ceramic top surface profile 252 can have a central high point 252A as well as edge locations 252B. The mesa profile 254 can exhibit grind locations 256A and 256B and has a high central point. The mesa 262 is on the ceramic top surface profile 252. In an embodiment, after determining that the central point is a high point, the mesa 262A is not formed at the central location. As a result, the wafer profile (dotted line 258) is not formed on the high point of the mesa profile 254 that would otherwise include the mesa 262A.

[0023] In an embodiment, the topmost layer above the high-voltage electrode is made thicker than 1 mm and less than 3 mm to strengthen the top surface and reduce the surface stress of the AlN ESC. In an embodiment, the brazed high-voltage connection is 2 - 4 mm from the top surface to reduce stress. In an embodiment, the topmost layer above the electrode consists of a high resistivity and high thermal shock resistance. In an embodiment, the microstructure design provides a thermal shock resistance of 400 degrees or more.

[0024] Referring again to FIGS. 1, 2A, and 2B, according to an embodiment of the present disclosure, the substrate support assembly includes a ceramic upper plate having an upper surface with a processing region. One or more DC brazed connections are within 1 - 2 mm from the surface of the ceramic upper plate. A plurality of mesas are within the processing region and on the upper surface of the ceramic plate. None of the plurality of mesas is vertically above one or more DC brazed connections.

[0025] Referring again to FIGS. 1, 2A and 2B, according to another embodiment of the present disclosure, the substrate support assembly includes a ceramic upper plate having an upper surface with a processing region. The upper surface has one or more high topography regions. A plurality of mesas are within the processing region and on the upper surface of the ceramic plate. None of the plurality of mesas are on one or more high topography regions of the upper surface of the processing region or above the high voltage electrode edge.

[0026] Referring again to FIGS. 1, 2A and 2B, according to another embodiment of the present disclosure, the substrate support assembly includes a ceramic upper plate having an upper surface with a processing region. The upper surface has one or more high stress regions. A plurality of mesas are within the processing region and on the upper surface of the ceramic plate. None of the plurality of mesas are on one or more high stress regions of the upper surface of the processing region.

[0027] FIG. 2C illustrates a cross-sectional view of an electrostatic chuck (ESC) including mesas in various locations, according to another embodiment of the present disclosure.

[0028] Referring to FIG. 2C, the ESC 270 includes a central zone 272, a main zone 274, a DC rod 276, and an ESC mesh 278. The DC rod 276 can be in a central location 280 as depicted. The ESC 270 also includes mesas such as mesas 282A, 282B, 282C, and 282D. Mesa 282A is above the high voltage connection area 280, such as above the DC rod 276. Mesa 282B is above the electrode edge. Mesa 282C is in an area without an electrode. Mesa 282D is entirely above the electrode. Mesas 282A, 282B, 282C, and 282D are located a relatively shallow distance above the ESC mesh 278. In contrast to FIG. 2A, in an embodiment, the ESC 270 of FIG. 2C includes a molybdenum high voltage electrode mesh 278 connected by a metal paste 290 via a via 292 of approximately 0.5 mm in a nickel rod 276 brazed within a few millimeters (e.g., 1 - 4 mm) inside the ceramic. In one such embodiment, the arrangement reduces stress on the top while maintaining electrical connection from the nickel rod to the molybdenum mesh through fine layers of paste in the horizontal mesh plane and in the vertical direction. In one embodiment, mesa 282D is in a location with relatively lower stress than mesa 212D of FIG. 2A.

[0029] More generally shown, as an exemplary fabricated ESC, FIG. 3 illustrates a cross - sectional view of an electrostatic chuck (ESC) according to an embodiment of the present disclosure.

[0030] Referring to FIG. 3, the ESC 300 includes a ceramic bottom plate 302 having a heater coil 304 therein. The heater coil 304 can be coupled to a heater connection 305 (in another embodiment, it should be understood that heater electrodes are screen printed in the case of tape cast AlN or AlN plate materials used for ESC manufacturing). A shaft 306 is coupled to the bottom surface of the ceramic bottom plate 302. The ESC 300 also includes a ceramic top plate 308. The ceramic top plate 308 has ESC (clamping) electrodes 310 or an electrode assembly therein. A layer 312, such as a metal layer or a diffusion bonding layer, can be used to couple the ceramic top plate 308 to the top surface of the ceramic bottom plate 302. A thermocouple 314 extends through openings 315 in the ceramic bottom plate 302 and in the metal layer 312. High voltage insulation 316 extends through the openings 315 in the ceramic bottom plate 302 and in the metal layer 312 and houses the ESC high voltage connection 318. The mesa covered surface 399 can be a mesa surface manufactured according to the embodiments described above.

[0031] Referring again to FIG. 3, according to an embodiment of the present disclosure, the substrate support assembly 300 includes a ceramic bottom plate 302 having a heater element 304 therein. The substrate support assembly 300 also includes a ceramic top plate 308 having electrodes 310 therein. A metal layer 312 is between the ceramic top plate 308 and the ceramic bottom plate 302. The ceramic top plate 308 is in direct contact with the metal layer 312, and the metal layer 312 is in direct contact with the ceramic bottom plate 302.

[0032] The standard way to make an ESC is a hot press by connecting the plates together and then diffusion bonding those plates to the shaft. In embodiments without diffusion bonding, the metal layer 312 provides the incorporation of a metal bond instead of a ceramic for ceramic diffusion bonding that could otherwise change the resistivity of the upper ceramic during the formation of the diffusion bond. In one embodiment, the metal layer 312 is a metal foil, such as an aluminum foil. In one such embodiment, the metal layer 312 is an aluminum foil impregnated with about 2% to 20% Si (e.g., as atomic % of the total foil composition), with the balance being aluminum or essentially all aluminum (in other words, the aluminum foil contains silicon having an atomic concentration within the range of 2% to 20% of the aluminum foil). In embodiments, the metal layer 312 is pre-patterned to include openings 315 and / or additional openings for accommodating, for example, lift pins. In one embodiment, the metal layer 312 is an aluminum foil having a thickness in the range of 50 to 500 microns and can be about 250 microns. In embodiments, the metal layer 312 is an aluminum foil and is cleaned prior to encapsulation in the ESC manufacturing process, for example, to remove a passivation layer prior to bonding. In embodiments, the metal layer 312 is an aluminum foil and can withstand corrosive processes, such as chlorine-based processes, without etching or degradation of the metal layer 312 while the ESC is in use. However, when used for non-chlorine-based processes, the metal layer 312 can be composed of a silver-copper alloy, for example, with or without the addition of titanium. In embodiments, the metal layer 312 is bonded to the upper plate 308 and the bottom plate 302 at a temperature below 600 degrees Celsius, more particularly below 300 degrees Celsius. It should be understood that higher ESC use temperatures, such as 650 degrees Celsius, can be used when metal bonding is performed using high-temperature metal bonding, such as silver-copper or gold-nickel temperatures, which are much lower than 1400 degrees Celsius but well above the 650 degrees Celsius use temperature.

[0033] Regarding the ceramic upper plate 308 having an ESC (clamping) electrode 310 therein, in an embodiment, the body of the upper plate can be formed by sintering a ceramic material such as aluminum nitride (AlN) or aluminum oxide powder or other suitable materials. An RF mesh can be embedded in the body. The RF mesh can have an electrical connection extending through the bottom surface of the body. The RF mesh can include a mesh of molybdenum or another suitable metallic material. In one embodiment, the mesh is a mesh with a diameter of about 125 microns. The materials can be sintered to form a monolithic structure. In one embodiment, the electrode 310 can be manufactured from a metallic material having a coefficient of thermal expansion similar to that of the body, such as molybdenum. In an embodiment, the ceramic upper plate 308 is targeted to withstand temperatures below 350 degrees Celsius, for example, between 150 and 300 degrees Celsius, and can include dopants to optimize operation within such a targeted temperature range.

[0034] The clamping electrode 310 can include at least a first electrode and a second electrode. During operation, a negative charge can be applied to the first electrode and a positive charge can be applied to the second electrode, or vice versa, to generate an electrostatic force. During chucking, the electrostatic force generated from the electrodes holds the substrate disposed thereon in a fixed position. When the power supplied from the power source is turned off, the charges present in the interface between the electrodes can be maintained over a long time period. To release the substrate held on the electrostatic chuck, a short pulse of power of opposite polarity can be provided to the electrodes to remove the charges present in the interface.

[0035] The electrode assembly can be formed by a metal bar, sheet, stick, foil and can be pre-formed, pre-cast, pre-manufactured and disposed on the surface of the insulating base during the manufacture of the electrostatic chuck. Alternatively, a metal deposition process can be implemented to deposit and form the electrode assembly directly on the upper surface of the insulating base. Suitable deposition processes can include PVD, CVD, plating, inkjet printing, rubber stamping, screen printing or aerosol printing processes. Additionally, a metal paste / metal line can be formed on the upper surface of the insulating base. The metal paste / metal line can initially be a liquid, paste or metal gel that is patterned on the surface of the object in a pattern for forming electrode fingers with different configurations or dimensions on the upper surface of the insulating base.

[0036] The ceramic top plate 308 or the ceramic bottom plate 302 can include, without limitation, aluminum nitride, glass, silicon carbide, aluminum oxide, yttrium-containing materials, yttrium oxide (Y2O3), yttrium aluminum garnet (YAG), titanium oxide (TiO), or titanium nitride (TiN). With respect to the ceramic bottom plate 302, in an embodiment, the ceramic bottom plate 308 is targeted to withstand a temperature of up to 650 degrees Celsius and can include dopants to optimize operation within such a targeted temperature range. In one embodiment, the ceramic bottom plate 302 has an aluminum nitride composition different from that of the aluminum nitride composition of the ceramic top plate 308. The heating element 304 included in the ceramic bottom plate 302 can use any suitable heating technique, such as resistive heating or inductive heating. The heating element 304 can be composed of a resistive metal, a resistive metal alloy, or a combination of the two. Suitable materials for the heating element can include those with high thermal resistance, such as tungsten, molybdenum, titanium, etc. In one embodiment, the heating element 304 is composed of a molybdenum wire. The heating element 304 may be manufactured using a material having thermal properties, such as a coefficient of thermal expansion, that substantially match at least one or both of the aluminum nitride bodies to reduce stress caused by mismatched thermal expansion.

[0037] In an embodiment, the ceramic top plate 308 is manufactured and then bonded to the ceramic bottom plate by a metal layer 312 (which may already include one or more openings patterned therein). In an embodiment, the metal layer 312 is bonded to the ceramic top plate 308 at the same time as the metal layer 312 is bonded to the ceramic bottom plate 302. In another embodiment, first, the metal layer 312 is bonded to the ceramic top plate 308, and then the ceramic top plate / metal layer 312 pairing is bonded to the ceramic bottom plate 302. In another embodiment, first, the metal layer 312 is bonded to the ceramic bottom plate 302, and then the ceramic bottom plate / metal layer 312 pairing is bonded to the ceramic top plate 308. In any case, in one particular embodiment, the ceramic top plate is formed from sintered aluminum nitride (AlN) or aluminum oxide (Al2O3) powder and a metal mesh.

[0038] In an embodiment, bonding the ceramic top plate 308 to the ceramic bottom plate 302 using the metal layer 312 includes heating the ceramic bottom plate 302, the metal layer 312, and the ceramic top plate 308 to a temperature below 600 degrees Celsius. In an embodiment, the metal layer 312 is an aluminum foil, and the method includes cleaning the surface of the aluminum foil to remove the passivation layer of the aluminum foil before bonding the ceramic top plate 308 to the ceramic bottom plate 302 using the metal layer 312.

[0039] In another aspect, FIG. 4 is a schematic cross-sectional view of a process chamber 400 including a substrate support assembly 428, according to an embodiment of the present disclosure. In the example of FIG. 4, the process chamber 400 is a plasma enhanced chemical vapor deposition (PECVD) chamber. As shown in FIG. 4, the process chamber 400 includes one or more sidewalls 402, a bottom 404, a gas distribution plate 410, and a cover plate 412. The sidewalls 402, the bottom 404, and the cover plate 412 together define a processing volume 406. The gas distribution plate 410 and the substrate support assembly 428 are disposed within the processing volume 406. The processing volume 406 is accessed through a sealable slit valve opening 408 formed through the sidewall 402, whereby a substrate 405 can be transferred into and out of the process chamber 400. A vacuum pump 409 is coupled to the chamber 400 to control the pressure within the processing volume 406.

[0040] The gas distribution plate 410 is coupled to the cover plate 412 at the outer periphery of the gas distribution plate 410. A gas source 420 is coupled to the cover plate 412 to provide one or more gases through the cover plate 412 into a plurality of gas passages 411 formed in the cover plate 412. The gases flow through the gas passages 411 into the processing volume 406 toward the substrate receiving surface 432.

[0041] The RF power source 422 is coupled to the cover plate 412 by the RF power supply 424 and / or directly to the gas distribution plate 410 to provide RF power to the gas distribution plate 410. Various RF frequencies can be used. For example, the frequency can be between about 0.3 MHz and about 200 MHz, such as about 13.56 MHz. The RF return path 425 couples the substrate support assembly 428 to the RF power source 422 through the sidewall 402. The RF power source 422 generates an electric field between the gas distribution plate 410 and the substrate support assembly 428. The electric field forms a plasma from the gas present between the gas distribution plate 410 and the substrate support assembly 428. The RF return path 425 completes the electrical circuit for the RF energy to prevent the floating plasma from causing RF arcing due to the voltage difference between the substrate support assembly 428 and the sidewall 402. Thereby, the RF return path 425 mitigates arcing that causes process drift, particle contamination, and damage to chamber components.

[0042] The substrate support assembly 428 includes a substrate support 430 and a stem 434. The stem 434 is coupled to a lift system 436 adapted to raise and lower the substrate support assembly 428. The substrate support 430 includes a substrate receiving surface 432 for supporting the substrate 405 during processing. Lift pins 438 are movably disposed through the substrate support 430 to facilitate movement of the substrate 405 onto and from the substrate receiving surface 432. An actuator 414 is utilized to extend and retract the lift pins 438. A ring assembly 433 can be disposed across the outer periphery of the substrate 405 during processing. The ring assembly 433 is configured to prevent or reduce unwanted deposition on the surface of the substrate support 430 that is not covered by the substrate 405 during processing.

[0043] The substrate support 430 may also include heating and / or cooling elements 439 for maintaining the substrate support 430 and the substrate 405 positioned thereon at a desired temperature. In one embodiment, the heating and / or cooling elements 439 may be utilized to maintain the temperature of the substrate support 430 and the substrate 405 disposed thereon below or at less than about 800 degrees Celsius during processing. In one embodiment, the heating and / or cooling elements 439 may be used to control the substrate temperature to less than 650 degrees Celsius, such as between 300 degrees Celsius and about 400 degrees Celsius. In embodiments, the substrate support 430 / substrate support assembly 428 is as described above.

[0044] In another aspect, FIG. 5 is a partial schematic cross-sectional view of a processing chamber 500 including a substrate support assembly 300, according to an embodiment of the present disclosure. The processing chamber 500 has a body 501. The body has sidewalls 502, a bottom 504, and a showerhead 512. The sidewalls 502, bottom 504, and showerhead 512 define an internal volume 506. In embodiments, a substrate support assembly 300, such as those described above, is disposed within the internal volume 506. An RF generator 580 may be coupled to an electrode 582 in the showerhead 512. The RF generator 580 may have an associated RF return path 588 for completing the RF circuit when plasma is present. Advantageously, an RF ground path for maintaining the plasma can be maintained, providing a long life to the substrate support assembly 300.

[0045] In embodiments, the semiconductor wafer or substrate supported by the substrate support assembly 300 is composed of a material suitable for withstanding the manufacturing process and on which a semiconductor processing layer can be properly disposed. For example, in one embodiment, the semiconductor wafer or substrate is composed of a Group-IV based material such as, but not limited to, crystalline silicon, germanium, or silicon / germanium. In certain embodiments, the semiconductor wafer is a single crystal silicon substrate. In certain embodiments, the single crystal silicon substrate is doped with impurity atoms. In another embodiment, the semiconductor wafer or substrate is composed of a III-V material.

[0046] Embodiments of the present disclosure may be provided as a computer program product or software that includes a machine-readable medium storing instructions, which may be used to program a computer system (or other electronic device) to perform a process according to embodiments of the present disclosure. In one embodiment, the computer system is coupled with the process chamber 400 and the substrate support assembly 428 described above in connection with FIG. 4, or the processing chamber 500 and the substrate support assembly 300 described in connection with FIG. 5. The machine-readable medium includes any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computer). For example, the machine-readable (e.g., computer-readable) medium includes a machine (e.g., computer) readable storage medium (e.g., read-only memory ("ROM"), random access memory ("RAM"), magnetic disk storage media, optical storage media, flash memory devices, etc.), a machine (e.g., computer) readable transmission medium (electrical, optical, acoustic, or other forms of propagated signals (e.g., infrared signals, digital signals, etc.)), and the like.

[0047] FIG. 6 illustrates a diagrammatic representation of a machine in an exemplary form of a computer system 600 within which a set of instructions can be executed to cause the machine to perform any one or more of the methodologies described herein. In alternative embodiments, the machine can be connected (e.g., networked) to other machines in a local area network (LAN), intranet, extranet, or the Internet. The machine can operate as a server or a client machine in a client-server network environment, or as a peer machine in a peer-to-peer (or distributed) network environment. The machine can be a personal computer (PC), tablet PC, set-top box (STB), personal digital assistant (PDA), cellular phone, web appliance, server, network router, switch or bridge, or any machine capable of executing a set (sequential or otherwise) of instructions that specify actions to be taken by that machine. Further, although only a single machine is illustrated, the term "machine" shall also be construed to include any collection of machines (e.g., computers) that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies described herein.

[0048] The exemplary computer system 600 includes a processor 602, main memory 604 (e.g., dynamic random access memory (DRAM) such as read only memory (ROM), flash memory, synchronous DRAM (SDRAM), or Rambus DRAM (RDRAM)), static memory 606 (e.g., flash memory, static random access memory (SRAM), etc.), and secondary memory 618 (e.g., a data storage device) that communicate with each other via bus 630.

[0049] Processor 602 represents one or more general-purpose processing devices, such as a microprocessor, a central processing unit, etc. More specifically, processor 602 can be a complex instruction set computing (CISC) microprocessor, a reduced instruction set computing (RISC) microprocessor, a very long instruction word (VLIW) microprocessor, a processor implementing other instruction sets, or a processor implementing a combination of instruction sets. Processor 602 can also be one or more dedicated processing devices, such as an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), a digital signal processor (DSP), a network processor, etc. Processor 602 is configured to execute processing logic 626 for performing the operations described herein.

[0050] Computer system 600 may further include a network interface device 608. Computer system 600 may also include a video display unit 610 (e.g., a liquid crystal display (LCD), a light emitting diode display (LED), or a cathode ray tube (CRT)), an alphanumeric input device 612 (e.g., a keyboard), a cursor control device 614 (e.g., a mouse), and a signal generation device 616 (e.g., a speaker).

[0051] Secondary memory 618 may include a machine-accessible storage medium (or more specifically, a computer-readable storage medium) 632 in which one or more sets of instructions (e.g., software 622) embodying any one or more of the methodologies or functions described herein are stored. Software 622 may also reside, in whole or at least in part, within main memory 604 and / or within processor 602 during execution of software 622 by computer system 600, and main memory 604 and processor 602 also constitute a machine-readable storage medium. Software 622 may further be transmitted or received over network 620 via network interface device 608.

[0052] The machine-accessible storage medium 632 is shown in an exemplary embodiment as a single medium, but the term "machine-readable storage medium" should be interpreted to include a single medium or a plurality of media (e.g., a centralized or distributed database, and / or associated cache and server) that store one or more sets of instructions. The term "machine-readable storage medium" should also be interpreted to include any medium that is capable of storing or encoding a set of instructions for machine execution and that causes a machine to perform any one or more of the methodologies of the present disclosure. The term "machine-readable storage medium" should, therefore, be interpreted to include, without limitation, solid state memory, as well as optical and magnetic media.

[0053] As described above, an electrostatic chuck (ESC) for a plasma processing chamber, and a method of manufacturing the ESC have been disclosed.

Claims

1. A ceramic upper plate having an upper surface with a processing area, One or more DC brazing connections within the ceramic upper plate, One or more electrodes within the ceramic upper plate, A plurality of mesas within the processing area and on the upper surface of the ceramic upper plate And a substrate support assembly, wherein none of the plurality of mesas is vertically above the one or more DC brazing connections, and some of the plurality of mesas are entirely above a corresponding one of the one or more electrodes.

2. The substrate support assembly according to claim 1, wherein the plurality of mesas are continuous with the upper surface of the ceramic upper plate.

3. The substrate support assembly according to claim 1, wherein the ceramic upper plate contains aluminum nitride.

4. The substrate support assembly according to claim 1, wherein the ceramic upper plate contains aluminum oxide.

5. The substrate support assembly according to claim 1, wherein the one or more electrodes contain molybdenum.

6. A ceramic upper plate having an upper surface with a processing area, A molybdenum mesh within the ceramic upper plate, A nickel rod in the ceramic upper plate, the nickel rod being coupled to the molybdenum mesh by a metal paste and being at a distance greater than 1 mm from the upper surface of the ceramic upper plate, A plurality of mesas within the processing area and on the upper surface of the ceramic upper plate, some of the plurality of mesas being entirely above the molybdenum mesh And a substrate support assembly comprising.

7. The substrate support assembly according to claim 6, wherein the metal paste contains tungsten or molybdenum.

8. The substrate support assembly according to claim 6, wherein the nickel rod is at a distance of 2 mm from the upper surface of the ceramic upper plate.

9. The substrate support assembly according to claim 6, wherein the ceramic upper plate contains aluminum nitride.

10. The substrate support assembly according to claim 6, wherein the ceramic upper plate contains aluminum oxide.

11. A ceramic upper plate having an upper surface with a processing region, wherein the upper surface has one or more high topography regions and one or more electrodes within the ceramic upper plate, the ceramic upper plate a plurality of mesas within the processing region and on the upper surface of the ceramic upper plate comprising, none of the plurality of mesas being on the one or more high topography regions of the upper surface of the processing region, some of the plurality of mesas being entirely above a corresponding one of the one or more electrodes, a substrate support assembly.

12. The substrate support assembly according to claim 11, wherein the plurality of mesas are continuous with the upper surface of the ceramic upper plate.

13. The substrate support assembly according to claim 11, wherein the ceramic upper plate contains aluminum nitride.

14. The substrate support assembly according to claim 11, wherein the ceramic upper plate contains aluminum oxide.

15. The substrate support assembly according to claim 11, further comprising one or more electrodes containing molybdenum.

16. A ceramic upper plate having an upper surface with a processing region, wherein the upper surface has one or more stress regions, the ceramic upper plate one or more electrodes within the ceramic upper plate, a plurality of mesas within the processing region and on the upper surface of the ceramic upper plate comprising, none of the plurality of mesas being on the one or more stress regions of the upper surface of the processing region, some of the plurality of mesas being entirely above a corresponding one of the one or more electrodes, a substrate support assembly.

17. The substrate support assembly according to claim 16, wherein the plurality of mesas are continuous with the upper surface of the ceramic upper plate.

18. The substrate support assembly according to claim 16, wherein the ceramic upper plate contains aluminum nitride.

19. The substrate support assembly according to claim 16, wherein the ceramic upper plate contains aluminum oxide.

20. The substrate support assembly according to claim 16, further comprising one or more electrodes containing molybdenum.

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