Electrostatic chuck assembly for low temperature applications

Abstract

FIELD OF THE DISCLOSURE Embodiments of the present disclosure generally relate to an electrostatic chuck assembly suitable for use in low temperature applications. In one or more embodiments, an electrostatic chuck assembly is provided that includes an electrostatic chuck having a substrate support surface opposite a bottom surface, a cooling plate having a top surface, the cooling plate including an aluminum alloy having a CTE of less than 22 ppm, and an adhesive layer securing the bottom surface of the electrostatic chuck and the top surface of the cooling plate, the adhesive layer including a silicone material.

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE Embodiments of the present disclosure relate generally to apparatus and processes for microelectronics manufacturing, and more particularly to a substrate support assembly having an electrostatic chuck assembly for use in low temperature applications. [Background technology]

[0002] Reliably producing nanometer and smaller features is one of the major technological challenges for the next generation of very large scale integration (VLSI) and ultra large scale integration (ULSI) semiconductor devices. However, as the limits of circuit technology are pushed, the shrinking dimensions of VLSI and ULSI interconnect technology are placing additional demands on processing power. Reliable formation of gate structures on substrates is critical to the success of VLSI and ULSI, as well as to the continuing effort to increase circuit density and quality of individual substrates and dies.

[0003] To lower manufacturing costs, integrated chip (IC) manufacturing demands higher throughput and better device yield and performance for every silicon substrate processed. Some manufacturing techniques currently being explored for next generation devices under development require processing at temperatures above 300° C. and high bias power during processing of films on the substrate. High bias power enhances the roughness and morphology of the films on the substrate. However, high bias power also provides thermal energy when the power is on.

[0004] Some of these high temperature and high power manufacturing techniques are performed in a processing chamber that utilizes an electrostatic chuck to ensure that the substrate is processed in the chamber. A conventional electrostatic chuck is part of a substrate support assembly that includes a cooling plate. The cooling plate is bonded to the electrostatic chuck. The materials utilized for the bond between the cooling plate and the electrostatic chuck are sensitive to high temperatures, thermal expansion, and high energy fields. Conventional electrostatic chucks can experience problems with the bonding material due to a combination of the aforementioned factors. For example, the bonding material can delaminate and fail completely, causing a loss of vacuum or movement in the substrate support. The processing chamber must be taken off-line to replace an electrostatic chuck that has a problem with the bonding material, thus unnecessarily increasing costs while decreasing processing yields.

[0005] In low temperature applications, the cooling plate is exposed to a cryogenic fluid to remove heat from the substrate. The cooling plate can be cooled to temperatures below 0° C., such as from about −10° C. to about −100° C. or lower. At such low temperatures, the electrostatic chuck and the cooling plate often separate due to delamination of the adhesive between their body interfaces. Delamination is caused by thermal stresses in the bodies resulting from differences in the thermal expansion coefficients of the various materials in the bodies. Standard adhesives typically cannot maintain adhesion at sub-freezing temperatures.

[0006] Therefore, there is a need for an improved substrate support assembly suitable for use in low temperature applications. Summary of the Invention

[0007] The embodiments of the present disclosure generally relate to electrostatic chuck (ESC) assemblies suitable for use in low temperature applications. The design of the ESC assembly utilizes management of stresses created by various factors. Cooling the ESC assembly to temperatures used in low temperature applications causes a change in thermal expansion coefficient with temperature. The ESC assemblies disclosed and discussed herein are able to handle the temperatures used in low temperature applications without cracking or delamination due to the specific materials with similar CTE values ​​used within the components of the ESC assembly.

[0008] In one or more embodiments, an electrostatic chuck assembly is provided that includes an electrostatic chuck having a substrate support surface opposite a bottom surface, a cooling plate having a top surface, the cooling plate comprising an aluminum alloy having a CTE less than 22 ppm, and an adhesion layer securing the bottom surface of the electrostatic chuck and the top surface of the cooling plate, the adhesion layer comprising a silicone material.

[0009] In some embodiments, an electrostatic chuck assembly is provided that includes an electrostatic chuck having a substrate support surface opposite a bottom surface, a cooling plate comprising an aluminum alloy having aluminum and silicon and having a CTE less than 22 ppm, and an adhesion layer comprising a silicone material and disposed between the electrostatic chuck and the cooling plate.

[0010] In another embodiment, an electrostatic chuck assembly is provided that includes an electrostatic chuck having a substrate support surface opposite a bottom surface, a cooling plate containing an aluminum alloy including aluminum and silicon and having a CTE less than 22 ppm, and an adhesion layer disposed between the electrostatic chuck and the cooling plate, the adhesion layer including a silicone layer, an indium-containing layer, and a secondary metal layer disposed between the silicone material and the indium-containing layer, the secondary metal layer including molybdenum, tungsten, chromium, and alloys thereof.

[0011] Thus, so that the above-mentioned features of the present disclosure can be understood in detail, a more particular description of the present disclosure briefly summarized above can be made by reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings depict merely exemplary embodiments and are therefore not to be considered as limiting the scope thereof, as other equally effective embodiments may be recognized. [Brief description of the drawings]

[0012] [Figure 1] 1 is a cross-sectional schematic side view of a processing chamber containing a substrate support assembly having an electrostatic chuck assembly in accordance with one or more embodiments described and discussed herein. [Diagram 2] FIG. 1 is a cross-sectional schematic side view of an electrostatic chuck assembly in accordance with one or more embodiments described and discussed herein. [Diagram 3] FIG. 1 is a cross-sectional schematic side view of another electrostatic chuck assembly in accordance with one or more embodiments described and discussed herein. [Figure 4] 1 is a cross-sectional schematic perspective view of a cooling plate according to one or more embodiments described and discussed herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] For ease of understanding, wherever possible, the same reference numbers have been used to designate identical elements common to the figures. It is contemplated that elements and features of one or more embodiments may be beneficially incorporated in other embodiments.

[0014] The embodiments of the present disclosure generally relate to an electrostatic chuck assembly suitable for use in low temperature applications. In one or more embodiments, the electrostatic chuck assembly is used at low temperature processing temperatures below 0° C. and below −10° C., such as about −50° C., about −80° C., or about −100° C. to about −110° C., about −120° C., about −135° C., or about −150° C. For example, the electrostatic chuck assembly is used at low temperature processing temperatures of about −50° C. to about −150° C.

[0015] 1 is a cross-sectional schematic diagram of an exemplary plasma processing chamber 100 shown configured as an etch chamber having a substrate support assembly 126. The substrate support assembly 126 may be utilized in other types of processing plasma chambers, such as plasma processing chambers, annealing chambers, physical vapor deposition (PVD) chambers, chemical vapor deposition (CVD) chambers, and ion implantation chambers, among others, as well as other systems in which the ability to control processing uniformity over a surface or substrate, such as a substrate, is desirable. Control of a dielectric property tangent (δ), such as dielectric loss, or ρ, such as volume resistivity, over an elevated temperature range for the substrate support assembly 126 advantageously enables azimuthal processing control, such as processing uniformity, for a substrate 124 disposed on the substrate support assembly 126.

[0016] The plasma processing chamber 100 includes a chamber body 102 having sidewalls 104, a bottom, and a lid 108 that surround an interior processing region 110. An injection device 112 is coupled to the sidewalls 104 and / or the lid 108 of the chamber body 102. A gas panel 114 is coupled to the injection device 112 to provide process gases into the processing region 110. The injection device 112 may be one or more nozzles or inlets, or alternatively, a showerhead. The process gases, as well as any process by-products, are removed from the processing region 110 through an exhaust port 128 formed in the sidewalls 104 or bottom 106 of the chamber body 102. The exhaust port 128 is coupled to a pumping system 132 that includes a throttle valve and a pump that are utilized to control the vacuum level in the processing region 110.

[0017] The process gas may be energized to form a plasma in the process region 110. The process gas may be energized by capacitively or inductively coupling RF power to the process gas. In the embodiment shown in Figure 1, a number of coils 116 are disposed on the lid 108 of the plasma processing chamber 100 and are coupled to an RF power source 120 via a matching network 118.

[0018] The substrate support assembly 126 is disposed within the processing region 110 below the ejection device 112. The substrate support assembly 126 includes an electrostatic chuck (ESC) 174 and a cooling plate 130. The cooling plate 130 is supported by a base plate 176. The base plate 176 is supported by one of the sidewalls 104 or the bottom 106 of the processing chamber. The substrate support assembly 126 may additionally include a heater assembly (not shown). In addition, the substrate support assembly 126 may include a fixture plate 145 and / or an insulator plate (not shown) disposed between the cooling plate 130 and the base plate 176 to facilitate electrical, cooling, and gas connections to the substrate support assembly 126.

[0019] The cooling plate 130 is formed of or otherwise contains one or more metallic materials. In one or more examples, the cooling plate 130 contains one or more aluminum alloys, one or more aluminum silicon alloys, one or more aluminum molybdenum alloys, one or more aluminum molybdenum silicon alloys, and other alloys and / or composite materials as further described and discussed herein. The cooling plate 130 includes a plurality of cooling channels 138 formed therein. The cooling channels 138 are connected to a heat transfer fluid source 122. The heat transfer fluid source 122 provides a heat transfer fluid, such as a liquid, gas, or combination thereof, that circulates through one or more cooling channels 138 disposed within the cooling plate 130. Fluid flowing through adjacent cooling channels 138 may be isolated to allow for localized control of heat transfer between the ESCs 180 and different regions of the cooling plate 130, which aids in controlling the lateral temperature profile of the substrate 124. In one or more embodiments, the heat transfer fluid circulating through the cooling channels 138 of the cooling plate 130 maintains the cooling plate 130 at a temperature below 0°C, such as from about -40°C to about -100°C.

[0020] The ESC 180 includes one or more chucking electrodes 186 disposed within a dielectric body 182. The dielectric body 182 of the ESC 180 has a substrate support surface 137 and a bottom surface 133 opposite the substrate support surface 137. The dielectric body 182 of the ESC 180 is fabricated from a ceramic material, such as alumina (Al2O3), aluminum nitride (AlN), or other suitable material. Alternatively, the dielectric body 182 may be fabricated from a polymer, such as polyimide, polyetheretherketone, polyaryletherketone, etc.

[0021] The dielectric body 182 optionally includes one or more embedded resistive heaters. The resistive heaters 188 are utilized to raise the temperature of the substrate support assembly 126 to a temperature suitable for processing the substrate 124 disposed on the substrate support surface 137 of the substrate support assembly 126. The resistive heaters 188 are coupled to a heater power supply 189 via the fixture plate 145. The heater power supply 189 may provide 900 watts or more of power to the resistive heaters 188. A controller (not shown) is utilized to control the operation of the heater power supply 189, which is typically set to heat the substrate 124 to a predefined temperature. In one or more embodiments, the resistive heaters 188 include multiple laterally separated heating zones that allow the controller to preferentially heat at least one zone of the resistive heaters 188 relative to resistive heaters 188 located in one or more of the other zones. For example, the resistive heaters 188 may be arranged concentrically within the multiple separated heating zones. The resistive heater 188 may maintain the substrate 124 at a temperature suitable for processing, such as between about 180°C and about 500°C, such as above about 250°C, such as between about 250°C and about 300°C.

[0022] In one or more embodiments, the dielectric body 182 of the ESC 180 has multiple heaters that create a microzone effect. As used herein, a microzone refers to a discrete temperature controllable area of ​​the ESC 180, and there may be from 10, about 50, about 80, or about 100 microzones, to about 120, about 150, about 200, or more microzones on the ESC 180. High temperature is intended to refer to a temperature above about 150° C., for example, above 300° C. An example of an ESC assembly described and discussed herein includes a cooling plate and an electrostatic chuck separated by an adhesive layer having thermal interface properties. The arrangement of the thermal interface between the ESC 180, the adhesive layer, and the cooling plate 130 reduces temperature loss and thermal smearing between the microzones in the ESC 180.

[0023] The ESC 180 generally includes a chucking electrode 186 embedded within a dielectric body 182. The chucking electrode 186 may be configured as a monopolar or bipolar electrode, or other suitable arrangement. The chucking electrode 186 is coupled through an RF filter to a chucking power supply 187, which provides DC power to the substrate support surface 137 of the ESC 180 to electrostatically secure the substrate 124. The RF filter prevents the RF power utilized to form a plasma (not shown) in the plasma processing chamber 100 from damaging electrical equipment or presenting electrical hazards outside the chamber.

[0024] The substrate support surface 137 of the ESC 180 includes gas passages (not shown) for providing a backside heat transfer gas to an interstitial space defined between the substrate 124 and the substrate support surface 137 of the ESC 180. The ESC 180 also includes lift pin holes for accommodating lift pins (not shown) for raising the substrate 124 above the substrate support surface 137 of the ESC 180 to facilitate robotic transfer in and out of the plasma processing chamber 100.

[0025] An adhesive layer 170 is disposed beneath the ESCs 180 and secures the ESCs 180 to the cooling plate 130. In other embodiments, the adhesive layer 170 is disposed between the ESCs 180 and a bottom plate disposed between the ESCs 180 and the cooling plate 130, as described further below. The adhesive layer 170 may have a thermal conductivity between about 0.1 W / mK and about 5 W / mK. The adhesive layer 170 may be formed of several layers that compensate for the different thermal expansions between the ESCs 180 and the underlying portion of the substrate support assembly 126, such as the cooling plate 130. The layers that comprise the adhesive layer 170 may be formed of different materials and will be discussed with reference to subsequent figures showing different embodiments.

[0026] In one or more embodiments, the ESC 180 includes a material having a coefficient of thermal expansion (CTE) of less than 15 parts per million (ppm), such as about 5 ppm to about 10 ppm. For example, the ESC 180, such as the body 182, can include alumina, aluminum nitride, or dopants thereof. In one or more examples, the ESC 180 includes about 50 to about 200 heaters disposed therein. Each heater can be capable of independently controlling the temperature within a respective zone.

[0027] 2 illustrates a cross-sectional schematic side view of an electrostatic chuck (ESC) assembly 200 according to one or more embodiments described and discussed herein. In one or more embodiments, the ESC assembly 200 includes an ESC 180 having a workpiece support surface opposite a bottom surface, a cooling plate 130 having a top surface, and an adhesive layer 170 securing the bottom surface of the ESC 180 and the top surface of the cooling plate 130. The adhesive layer 170 contains or includes one or more silicone materials. The cooling plate 130 contains an aluminum alloy having a CTE of less than 24 ppm, less than 32 ppm, or less than 20 ppm.

[0028] In one or more embodiments, the aluminum alloy contains aluminum, silicon, and one or more metals other than aluminum. For example, the other metals can be or include molybdenum, tungsten, chromium, iron, nickel, titanium, zirconium, iron-nickel-cobalt alloys, alloys thereof, and / or any combination thereof.

[0029] In some embodiments, the aluminum alloy contains from about 25 atomic percent (at%), about 30 at%, about 40 at%, about 50 at%, or about 55 at%, to about 60 at%, about 70 at%, about 80 at%, about 85 at%, about 90 at%, about 95 at%, or about 99 at% aluminum. In some examples, the aluminum alloy contains from about 80 at%, about 82 at%, about 85 at%, about 88 at%, or about 90 at%, to about 92 at%, about 94 at%, about 95 at%, about 96 at%, about 97 at%, about 98 at%, or about 99 at% aluminum.

[0030] The aluminum alloy may contain from about 0.1 at%, about 0.2 at%, about 0.5 at%, about 1 at%, about 2 at%, about 3 at%, about 5 at%, about 6 at%, or about 8 at% silicon to about 10 at%, about 12 at%, about 15 at%, about 20 at%, about 25 at%, about 30 at%, about 35 at%, or about 40 at% silicon. The aluminum alloy may contain from about 25 at%, about 30 at%, about 35 at%, or about 40 at% silicon to about 45 at%, or about at50% silicon of one or more other metals (e.g., molybdenum, tungsten, chromium, iron, nickel, titanium, zirconium).

[0031] In one or more examples, the aluminum alloy contains aluminum, silicon, and at least one metal selected from molybdenum, tungsten, chromium, or alloys thereof. For example, the aluminum alloy contains about 30 at% to about 60 at% aluminum, about 30 at% to about 60 at% molybdenum, and about 5 at% to about 30 at% silicon. In another example, the aluminum alloy (e.g., 4032Al) contains about 80 at% to about 90 at% aluminum, and about 5 at% to about 20 at% silicon. In a further example, the aluminum alloy (e.g., 6061Al) includes at least 95 at% aluminum, about 0.5 at% to about 2 at% magnesium, and about 0.2 at% to about 1.5 at% silicon.

[0032] The aluminum alloy has a CTE of less than 24 ppm, such as less than 22 ppm, less than 20 ppm, and / or less than 18 ppm. In some embodiments, the aluminum alloy has a CTE of about 3 ppm, about 4 ppm, about 5 ppm, about 6 ppm, about 7 ppm, about 8 ppm, or about 9 ppm to about 10 ppm, about 12 ppm, about 14 ppm, about 15 ppm, about 16 ppm, about 18 ppm, about 19 ppm, about 20 ppm, about 21 ppm, about 22 ppm, about 23 ppm, or about 24 ppm. In one or more examples, the aluminum alloy has a CTE of about 4 ppm to about 16 ppm. In other examples, the aluminum alloy has a CTE of about 5 ppm to about 15 ppm. In some examples, the aluminum alloy has a CTE of about 7 ppm to about 12 ppm.

[0033] The cooling plate 130 can have a thickness of about 0.1 inches, about 0.2 inches, about 0.25 inches, about 0.4 inches, or about 0.5 inches to about 0.6 inches, about 0.8 inches, about 1 inch, about 1.2 inches, about 1.5 inches, about 1.8 inches, about 2 inches, or more. In one or more examples, the cooling plate 130 can have a thickness of about 0.1 inches to about 2 inches, such as about 0.5 inches to about 1.5 inches, or about 0.25 inches to about 1 inch.

[0034] In one or more embodiments, adhesive layer 170 can be or contain one, two, or more types of silicone materials. In some examples, the silicone material of adhesive layer 170 can be or include one or more alkylphenyl silicones. Exemplary alkylphenyl silicones can be or include methylphenyl silicone, ethylphenyl silicone, propylphenyl silicone, butylphenyl silicone, polymers thereof, elastomers thereof, or any combination thereof.

[0035] The silicone material typically has a CTE of less than 150 ppm. For example, the silicone material can have a CTE of about 30 ppm, about 50 ppm, or about 80 ppm to about 100 ppm, about 120 ppm, or about 145 ppm. The silicone material can have a glass transition of less than -60°C. For example, the silicone material can have a glass transition of about -100°C to about -150°C. The silicone material can have a Young's modulus of about 0.5 MPa to about 5 MPa. In some examples, the silicone material has a Young's modulus of less than 1 MPa, such as about 0.5 MPa, about 0.6 MPa, or about 0.7 MPa to about 0.8 MPa, about 0.9 MPa, or about 0.95 MPa.

[0036] Adhesive layer 170 can have a thickness of from about 0.1 mm to about 1.2 mm, such as from about 0.3 mm to about 0.9 mm, from about 0.4 mm to about 0.8 mm, or from about 0.5 mm to about 0.7 mm.

[0037] In some examples, adhesive layer 170 contains one or more silicone materials under the trade name NuSil® available from Avantor, Inc. Exemplary NuSil® silicones can be or include one or more of NuSil® R3-2160 two-part adhesive / sealant containing a silicone elastomer and useful for application at temperatures from about 0° C. to about −140° C., NuSil® R-2655 and NuSil® R2560 two-part silicones useful for application at temperatures from about 0° C. to about −115° C., NuSil® R-2949 thermally conductive two-part adhesive useful for application at temperatures from about 0° C. to about −115° C., and NuSil® R-2634 conductive silicone adhesive useful for application at temperatures from about 0° C. to about −140° C.

[0038] 3 illustrates a cross-sectional schematic side view of another electrostatic chuck (ESC) assembly 300 according to one or more embodiments described and discussed herein. In one or more embodiments, the ESC assembly 300 includes an ESC 180, a cooling plate 130 containing an aluminum alloy, the aluminum alloy containing aluminum and silicon and having a CTE of less than 22 ppm. An adhesive film 302 is disposed between the ESC 180 and the cooling plate 130. The adhesive film 302 can include an adhesive layer 170 containing one or more silicone materials.

[0039] In some embodiments, the adhesive film 302 further includes a secondary metal layer 160 disposed between the adhesive layer 170 and the cooling plate 130. The secondary metal layer 160 includes a metal selected from molybdenum, tungsten, chromium, iron, nickel, titanium, zirconium, iron-nickel-cobalt alloys, alloys thereof, and any combination thereof. In one or more examples, an exemplary iron-nickel-cobalt alloy can be KOVAR® alloy and can have about 53.4 wt% iron, about 29 wt% nickel, about 17 wt% cobalt, about 0.2% silicon, about 0.3% manganese, and less than about 0.01% carbon.

[0040] The secondary metal layer 160 contains molybdenum metal, a molybdenum alloy, tungsten metal, a tungsten alloy, chromium metal, or a chromium alloy. The secondary metal layer 160 can have a thickness of about 3 mm to about 12 mm, such as about 5 mm to about 10 mm. The secondary metal layer 160 can have a CTE of less than 12 ppm, such as about 3 ppm to about 8 ppm.

[0041] In one or more embodiments, the adhesive film 302 further includes an indium-containing layer 150 disposed between the secondary metal layer 160 and the cooling plate 130. The indium-containing layer 150 includes metallic indium or an indium alloy. The indium-containing layer has a thickness of about 100 μm to about 1,000 μm, such as about 200 μm to about 500 μm, about 250 μm to about 450 μm, or about 300 μm to about 400 μm.

[0042] In some embodiments, the ESC assembly 300 includes an ESC 180, a cooling plate 130 containing an aluminum alloy, where the aluminum alloy contains aluminum and silicon and has a CTE less than 22 ppm, and an adhesive film 302 disposed between the ESC 180 and the cooling plate 130. In one or more examples, the adhesive film 302 contains an adhesive layer 170 containing one or more silicone materials, an indium-containing layer 150, and a secondary metal layer 160 disposed between the adhesive layer 170 and the indium-containing layer 150. The secondary metal layer 160 can be or include molybdenum, tungsten, chromium, and alloys thereof.

[0043] FIG. 4 illustrates a cross-sectional schematic perspective view of a cooling plate 400 according to one or more embodiments described and discussed herein. In one or more embodiments, the cooling plate 130 illustrated in FIGS. 1-3 can be used as a replacement or substitute for the cooling plate 400 described and discussed herein. In some embodiments, the cooling plate 400 has a body 410 that contains one, two, or more internal channels 402, one, two, or more channels 404, and one, two, or more passages 406. Although the cooling plate 400 illustrated in FIG. 4 illustrates one channel 402, two channels 404, and four passages 406, the cooling plate 400 may contain different amounts of channels 402, channels 404, and passages 406. For example, although not shown, the cooling plate 400 may have 1-3 channels 402, 1-4 channels 404, and / or 1-100 passages 406. In one or more configurations, each of the internal channels 402 is coupled and fluidly connected to a cooling or heat transfer fluid, each of the channels 404 is coupled and fluidly connected to a process gas (e.g., helium, argon, neon, dinitrogen, or combinations thereof), and the passages 406 are coupled and fluidly connected to each of the channels 404.

[0044] The cooling plate 400 has a body 410 containing a stack of intermediate sheets or layers including at least a first layer 412 and a second layer 414, each of which independently contains a different metal from the other, each metal having a different CTE. In one or more embodiments, the first layer 412 can be or can include one or more metals selected from copper, indium, magnesium, alloys thereof, and any combination thereof, and the second layer 414 can be or can include one or more metals selected from molybdenum, tungsten, chromium, iron, nickel, titanium, zirconium, one or more iron-nickel-cobalt alloys (KOVAR® alloy, described and discussed above), alloys thereof, and any combination thereof.

[0045] In other embodiments, the cooling plate 400 includes a stack of alternating layers including a first layer 412 and a second layer 414, where the first layer 412 includes an aluminum alloy and the second layer 414 includes molybdenum. In one or more examples, the aluminum alloy includes from about 5 at% to about 40 at%, from about 8 at% to about 20 at%, or from about 10 at% to about 18 at% silicon.

[0046] 4 shows the cooling plate 400 with five first layers 412 and five second layers 414, the cooling plate 400 can have a variety of different amounts of first layers 412 and second layers 414, respectively. The cooling plate 400 can have from 1, 2, 3, 4, 5, 8, 10, 15, 18, 19, or 20 to 22, about 25, about 30, about 50, about 80, or about 100 layers, respectively, of the first layers 412 and second layers 414. For example, the cooling plate 400 can have a stack (of first layers 412 and second layers 414) containing from about 5 first layers 412 to about 50 first layers 412 and from about 5 second layers 414 to about 50 second layers 414. In other examples, the stack contains from about 12 first layers 412 to about 30 first layers 412 and from about 12 second layers 414 to about 30 second layers 414 .

[0047] The first layer 412 can have a thickness of about 0.1 mm to about 1 mm, such as about 0.2 mm to about 0.5 mm. The second layer 414 can have a thickness of about 0.5 mm to about 2.5 mm, such as about 0.8 mm to about 1.2 mm. The stack (of the first layer 412 and the second layer 414) and / or the cooling plate 400 can have a thickness of about 8 mm to about 35 mm, such as about 15 mm to about 25 mm. In some examples, the first layer 412 and the second layer 414 are bonded or otherwise adhered together using heat in a furnace or by application of heat and pressure to hermetically bond or adhere them tightly at the interface.

[0048] Embodiments of the present disclosure further relate, by way of example and not by way of limitation, to any one or more of Examples 1-46 below.

[0049] Example 1. An electrostatic chuck assembly comprising: an electrostatic chuck having a workpiece support surface opposite a bottom surface; a cooling plate having a top surface, the cooling plate comprising an aluminum alloy having a coefficient of thermal expansion (CTE) of less than 22 parts per million (ppm); and an adhesive layer securing the bottom surface of the electrostatic chuck and the top surface of the cooling plate, the adhesive layer comprising a silicone material.

[0050] Example 2. An electrostatic chuck assembly comprising: an electrostatic chuck having a workpiece support surface opposite a bottom surface; a cooling plate comprising an aluminum alloy, the aluminum alloy comprising aluminum and silicon and having a CTE of less than 22 ppm; and an adhesive film disposed between the electrostatic chuck and the cooling plate, the adhesive film comprising an adhesive layer comprising a silicone material.

[0051] Example 3. An electrostatic chuck assembly comprising: an electrostatic chuck having a workpiece support surface opposite a bottom surface; a cooling plate comprising an aluminum alloy, the aluminum alloy comprising aluminum and silicon and having a CTE of less than 22 ppm; and an adhesive film disposed between the electrostatic chuck and the cooling plate, the adhesive film comprising an adhesion layer comprising a silicone material, an indium-containing layer, and a secondary metal layer disposed between the adhesion layer and the indium-containing layer, the secondary metal layer comprising molybdenum, tungsten, chromium, and alloys thereof.

[0052] Example 4. The electrostatic chuck assembly of any one of Examples 1-3, wherein the aluminum alloy comprises from about 80 atomic percent (at%) to about 90 at% aluminum and from about 5 at% to about 20 at% silicon.

[0053] Example 5. The electrostatic chuck assembly of any one of Examples 1-4, wherein the aluminum alloy comprises aluminum, silicon, and at least one metal selected from the group consisting of molybdenum, tungsten, chromium, and alloys thereof.

[0054] Example 6. The electrostatic chuck assembly of any one of Examples 1-5, wherein the aluminum alloy comprises from about 30 at% to about 60 at% aluminum, from about 30 at% to about 60 at% molybdenum, and from about 5 at% to about 30 at% silicon.

[0055] Example 7. The electrostatic chuck assembly of any one of Examples 1-6, wherein the aluminum alloy has a coefficient of thermal expansion less than 20 ppm.

[0056] Example 8. The electrostatic chuck assembly of any one of Examples 1-7, wherein the aluminum alloy has a CTE of less than 18 ppm.

[0057] Example 9. The electrostatic chuck assembly of any one of Examples 1-8, wherein the aluminum alloy has a CTE of from about 4 ppm to about 16 ppm.

[0058] Example 10. The electrostatic chuck assembly of any one of Examples 1-9, wherein the cooling plate has a thickness of from about 0.1 inches to about 2 inches.

[0059] Example 11. The electrostatic chuck assembly of any one of Examples 1-10, wherein the cooling plate has a thickness of about 0.25 inches to about 1 inch.

[0060] Example 12. The electrostatic chuck assembly of any one of Examples 1-11, wherein the cooling plate comprises an intermediate sheet or stack of layers comprising at least a first layer and a second layer, each of the first layer and the second layer independently comprising a different metal from the other, each metal having a different CTE.

[0061] Example 13. The electrostatic chuck assembly of any one of Examples 1-12, wherein the first layer comprises one or more metals selected from the group consisting of copper, indium, magnesium, alloys thereof, and any combination thereof, and the second layer comprises one or more metals selected from the group consisting of molybdenum, tungsten, chromium, iron, nickel, titanium, zirconium, iron-nickel-cobalt alloys, alloys thereof, and any combination thereof.

[0062] Example 14. The electrostatic chuck assembly of any one of Examples 1-13, wherein the cooling plate comprises a stack of alternating layers comprising a first layer and a second layer, the first layer comprising an aluminum alloy and the second layer comprising molybdenum.

[0063] Example 15. The electrostatic chuck assembly of any one of Examples 1-14, wherein the aluminum alloy comprises from about 5 at% to about 40 at% silicon.

[0064] Example 16. The electrostatic chuck assembly of any one of Examples 1-15, wherein the aluminum alloy comprises from about 8 at% to about 20 at% silicon.

[0065] Example 17. The electrostatic chuck assembly of any one of Examples 1-16, wherein the stack comprises from about 5 first layers to about 50 first layers and from about 5 second layers to about 50 second layers.

[0066] Example 18. The electrostatic chuck assembly of any one of Examples 1-17, wherein the stack comprises from about 12 first layers to about 30 first layers and from about 12 second layers to about 30 second layers.

[0067] Example 19. The electrostatic chuck assembly of any one of Examples 1-18, wherein the first layer has a thickness of from about 0.1 mm to about 1 mm.

[0068] Example 20. The electrostatic chuck assembly of any one of Examples 1-19, wherein the first layer has a thickness of about 0.2 mm to about 0.5 mm.

[0069] Example 21. The electrostatic chuck assembly of any one of Examples 1-20, wherein the second layer has a thickness of from about 0.5 mm to about 2.5 mm.

[0070] Example 22. The electrostatic chuck assembly of any one of Examples 1-21, wherein the second layer has a thickness of from about 0.8 mm to about 1.2 mm.

[0071] Example 23. The electrostatic chuck assembly of any one of Examples 1-22, wherein the stack has a thickness of from about 8 mm to about 35 mm.

[0072] Example 24. The electrostatic chuck assembly of any one of Examples 1-23, wherein the cooling plate comprises a plurality of channels formed therein.

[0073] Example 25. The electrostatic chuck assembly of any one of Examples 1-24, wherein the adhesive layer has a thickness of about 0.1 mm to about 1.2 mm.

[0074] Example 26. The electrostatic chuck assembly of any one of Examples 1-25, wherein the adhesive layer has a thickness of about 0.3 mm to about 0.9 mm.

[0075] Example 27. The electrostatic chuck assembly of any one of Examples 1-26, wherein the silicone material of the adhesion layer comprises an alkylphenyl silicone.

[0076] Example 28. The electrostatic chuck assembly of any one of Examples 1-27, wherein the silicone material has a CTE of less than 150 ppm.

[0077] Example 29. The electrostatic chuck assembly of any one of Examples 1-28, wherein the silicone material has a glass transition of less than -60°C.

[0078] Example 30. The electrostatic chuck assembly of any one of Examples 1-29, wherein the silicone material has a glass transition from about -100°C to about -150°C.

[0079] Example 31. The electrostatic chuck assembly of any one of Examples 1-30, wherein the silicone material has a Young's modulus of about 0.5 MPa to about 5 MPa.

[0080] Example 32. The electrostatic chuck assembly of any one of Examples 1-31, wherein the silicone material has a Young's modulus of less than 1 MPa.

[0081] Example 33. The electrostatic chuck assembly of any one of Examples 1-32, wherein the electrostatic chuck comprises alumina, aluminum nitride, or a dopant thereof.

[0082] Example 34. The electrostatic chuck assembly of any one of Examples 1-33, wherein the electrostatic chuck comprises a material having a CTE of less than 15 ppm.

[0083] Example 35. The electrostatic chuck assembly of any one of Examples 1-34, wherein the electrostatic chuck comprises a material having a CTE of from about 5 ppm to about 10 ppm.

[0084] Example 36. An electrostatic chuck assembly as described in any one of Examples 1 to 35, wherein the electrostatic chuck includes about 50 heaters to about 200 heaters disposed therein, and each heater can be capable of independently controlling the temperature within a respective zone.

[0085] Example 37. The electrostatic chuck assembly of any one of Examples 1-36, wherein the adhesive film further comprises a secondary metal layer disposed between the adhesive film and the cooling plate, the secondary metal layer comprising a metal selected from the group consisting of molybdenum, tungsten, chromium, iron, nickel, titanium, zirconium, iron-nickel-cobalt alloys, alloys thereof, and any combination thereof.

[0086] Example 38. The electrostatic chuck assembly of any one of Examples 1-37, wherein the secondary metal layer comprises molybdenum metal, a molybdenum alloy, tungsten metal, a tungsten alloy, chromium metal, or a chromium alloy.

[0087] Example 39. The electrostatic chuck assembly of any one of Examples 1-38, wherein the secondary metal layer has a thickness of from about 3 mm to about 12 mm.

[0088] Example 40. The electrostatic chuck assembly of any one of Examples 1-39, wherein the secondary metal layer has a thickness of from about 5 mm to about 10 mm.

[0089] Example 41. The electrostatic chuck assembly of any one of Examples 1-40, wherein the secondary metal layer has a CTE of less than 12 ppm.

[0090] Example 42. The electrostatic chuck assembly of any one of Examples 1-41, wherein the secondary metal layer has a CTE of from about 3 ppm to about 8 ppm.

[0091] Example 43. The electrostatic chuck assembly of any one of Examples 1-42, wherein the adhesive film further comprises an indium-containing layer disposed between the secondary metal layer and the cooling plate.

[0092] Example 44. The electrostatic chuck assembly of any one of Examples 1-43, wherein the indium-containing layer comprises metallic indium or an indium alloy.

[0093] Example 45. The electrostatic chuck assembly of any one of Examples 1-44, wherein the indium-containing layer has a thickness of from about 100 μm to about 1,000 μm.

[0094] Example 46. The electrostatic chuck assembly of any one of Examples 1-45, wherein the indium-containing layer has a thickness of from about 200 μm to about 500 μm.

[0095] The foregoing is directed to embodiments of the present disclosure, but other and further embodiments may be devised without departing from the basic scope thereof, the scope of which is determined by the following claims. All documents described herein, including any priority documents and / or testing procedures to the extent not inconsistent herein, are incorporated herein by reference. As is apparent from the summary and specific embodiments set forth above, while forms of the disclosure have been illustrated and described, various modifications can be made without departing from the spirit and scope of the disclosure. Thus, the disclosure is not intended to be limited by those forms. Similarly, the term "comprising" is considered synonymous with the term "including" for purposes of U.S. law. Similarly, whenever a composition, element, or group of elements precedes the transitional phrase "comprising," it will be understood that the same composition, or group of elements, with the transitional phrase "consisting essentially of," "consisting of," "selected from the group consisting of," or "is," preceding the description of the composition, element, or multiple elements, or vice versa, is contemplated. As used herein, the term "about" refers to a + / - 10% variation from the nominal value. It is understood that such a variation may be included in any value provided herein.

[0096] Certain embodiments and features have been described using a set of upper numerical limits and a set of lower numerical limits. It is to be understood that ranges including any two value combinations are contemplated, for example, any lower limit with any upper limit, any two lower limits, and / or any two upper limits, unless otherwise stated. Particular lower limits, upper limits, and ranges are set forth within one or more claims below.

Claims

1. an electrostatic chuck having a workpiece support surface opposite a bottom surface; a cooling plate having a top surface, the cooling plate comprising an aluminum alloy having a coefficient of thermal expansion (CTE) of less than 22 parts per million (ppm), and comprising a stack of alternating layers comprising a first layer and a second layer, the first layer comprising the aluminum alloy and the second layer comprising molybdenum; an adhesion layer securing the bottom surface of the electrostatic chuck and the top surface of the cooling plate, the adhesion layer comprising a silicone material; An electrostatic chuck assembly comprising:

2. 2. The electrostatic chuck assembly of claim 1, wherein the aluminum alloy comprises from 80 atomic percent (at%) to 90 at% aluminum and from 5 at% to 20 at% silicon.

3. 2. The electrostatic chuck assembly of claim 1, wherein the aluminum alloy comprises aluminum, silicon, and at least one metal selected from the group consisting of molybdenum, tungsten, chromium, and alloys thereof.

4. 10. The electrostatic chuck assembly of claim 1, wherein the aluminum alloy comprises 30 at% to 60 at% aluminum, 30 at% to 60 at% molybdenum, and 5 at% to 30 at% silicon.

5. 10. The electrostatic chuck assembly of claim 1, wherein the aluminum alloy has a coefficient of thermal expansion of less than 20 ppm.

6. 2. The electrostatic chuck assembly of claim 1, wherein the cooling plate comprises an intermediate sheet or stack of layers comprising at least a first layer and a second layer, each of the first layer and the second layer independently comprising a different metal from the other, each metal having a different CTE.

7. 7. The electrostatic chuck assembly of claim 6, wherein the first layer comprises one or more metals selected from the group consisting of copper, indium, magnesium, alloys thereof, and any combination thereof, and the second layer comprises one or more metals selected from the group consisting of molybdenum, tungsten, chromium, iron, nickel, titanium, zirconium, iron-nickel-cobalt alloys, alloys thereof, and any combination thereof.

8. An electrostatic chuck assembly as described in claim 1, wherein the stack of alternating layers comprises two or more first layers and two or more second layers.

9. 10. The electrostatic chuck assembly of claim 1, wherein the aluminum alloy comprises from 5 at% to 40 at% silicon.

10. 2. The electrostatic chuck assembly of claim 1, wherein the stack comprises between 5 first layers and 5 second layers and between 5 second layers and 50 second layers, the first layers having a thickness between 0.1 mm and 1 mm, and the second layers having a thickness between 0.5 mm and 2.5 mm.

11. 10. The electrostatic chuck assembly of claim 1, wherein the silicone material of the adhesion layer comprises an alkylphenyl silicone.

12. 2. The electrostatic chuck assembly of claim 1, wherein the silicone material has a CTE of less than 150 ppm, a glass transition of less than -60° C., and a Young's modulus of less than 1 MPa.

13. 10. The electrostatic chuck assembly of claim 1, wherein the electrostatic chuck comprises between 50 and 200 heaters disposed therein, each heater capable of independently controlling a temperature within a respective zone.

14. an electrostatic chuck having a workpiece support surface opposite a bottom surface; a cooling plate comprising an aluminum alloy, the aluminum alloy comprising aluminum and silicon and having a coefficient of thermal expansion (CTE) of less than 22 parts per million (ppm); an adhesive film disposed between the electrostatic chuck and the cooling plate, the adhesive film comprising an adhesive layer comprising a silicone material, and further comprising a secondary metal layer disposed between the adhesive film and the cooling plate, the secondary metal layer comprising a metal selected from the group consisting of molybdenum, tungsten, chromium, iron, nickel, titanium, zirconium, iron-nickel-cobalt alloys, alloys thereof, and any combination thereof; An electrostatic chuck assembly comprising:

15. An electrostatic chuck assembly as described in claim 14, wherein the secondary metal layer comprises a metal selected from the group consisting of molybdenum, tungsten, chromium, alloys thereof, and any combination thereof.

16. 15. The electrostatic chuck assembly of claim 14, wherein the secondary metal layer comprises molybdenum metal, a molybdenum alloy, tungsten metal, a tungsten alloy, chromium metal, or a chromium alloy.

17. 15. The electrostatic chuck assembly of claim 14, wherein the secondary metal layer has a thickness of from 3 mm to 12 mm and a CTE of less than 12 ppm.

18. 15. The electrostatic chuck assembly of claim 14, wherein the adhesive film further comprises an indium-containing layer disposed between the secondary metal layer and the cooling plate.

19. 20. The electrostatic chuck assembly of claim 18, wherein the indium-containing layer comprises metallic indium or an indium alloy and has a thickness of from 100 μm to 1,000 μm.

20. an electrostatic chuck having a workpiece support surface opposite a bottom surface; a cooling plate comprising an aluminum alloy, the aluminum alloy comprising aluminum and silicon and having a coefficient of thermal expansion (CTE) of less than 22 parts per million (ppm); an adhesive film disposed between the electrostatic chuck and the cooling plate; The adhesive film comprises: an adhesive layer comprising a silicone material; an indium-containing layer; and a secondary metal layer disposed between the adhesion layer and the indium-containing layer, the secondary metal layer comprising molybdenum, tungsten, chromium, and alloys thereof; An electrostatic chuck assembly comprising:

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