Thermal interface component for a plasma processing tool

Abstract

Examples disclosed herein relate to a thermal interface component for a plasma processing tool and a plasma processing tool having a thermal interface component. In an example, a plasma processing tool includes an outer electrode surrounding an inner electrode and a gas distribution plate. The plasma processing tool further includes a thermal interface component located between the gas distribution plate and one or more of the inner electrode and the outer electrode. The thermal interface component includes a non-silicone polymer elastomer as a continuous phase and thermally conductive particles as a dispersed phase.

Description

Background Technology

[0001] Thermal interface components can be used to transfer heat between components of a processing tool. For example, thermal interface components can serve as interfaces between electrodes and gas distribution plates, between electrostatic chucks and thermal control elements, and / or between electrostatic chucks and the conductive base plate of the processing chamber. Thermal interface components in these locations help prevent temperature drift during substrate processing and thus contribute to achieving proper uniformity during substrate processing. Summary of the Invention

[0002] This invention is provided to introduce the chosen concepts in a simplified form, which will be further described in the following detailed implementations. This invention is not intended to identify key or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that address any or all of the shortcomings mentioned in any part of this disclosure.

[0003] The examples disclosed herein relate to a thermal interface component for a plasma processing tool and a plasma processing tool having the thermal interface component. In one example, the plasma processing tool includes an outer electrode surrounding an inner electrode and a gas distribution plate. The plasma processing tool also includes a thermal interface component located between the gas distribution plate and one or more of the inner and outer electrodes. The thermal interface component includes a non-silicone polymer elastomer as a continuous phase and thermally conductive particles as a dispersed phase.

[0004] In some such examples, the gas distribution plate includes multiple gas distribution openings, and the thermal interface component includes multiple holes positioned to match the gas distribution openings.

[0005] Additionally or alternatively, in some such examples, the plasma processing tool includes an edge ring and also includes a second thermal interface component located between the edge ring and the substrate support.

[0006] Additionally or alternatively, in some such examples, the non-silicone polymer elastomer comprises one or more of an epoxy-based matrix or a fluorocarbon-based matrix.

[0007] Additionally or alternatively, in some such examples, the thickness of the thermal interface component is >0.4 mm.

[0008] Additionally or alternatively, in some such examples, the AC breakdown voltage of the thermal interface component is >4.0 kV.

[0009] Additionally or alternatively, in some such examples, the thermal conductivity of the thermal interface component is in the range of 2.0 W / mK to 40 W / mK.

[0010] Additionally or alternatively, in some such examples, the relative permittivity of the thermal interface component is in the range of 2–4.

[0011] Additionally or alternatively, in some such examples, the thermal interface component includes a core layer sandwiched between a first thermal interface component layer and a second thermal interface component layer.

[0012] Additionally or alternatively, in some such examples, the thermally conductive particles are electrically insulating.

[0013] Additionally or alternatively, in some such examples, the thermally conductive particles contain boron nitrides.

[0014] Additionally or alternatively, in some such examples, the thermally conductive particles are electrically conductive.

[0015] Additionally or alternatively, in some such examples, the thermally conductive particles contain carbon fibers.

[0016] In another embodiment, a thermal interface component for an electrode assembly of a plasma processing tool is provided. This thermal interface component comprises a non-silicone polymer elastomer as a continuous phase and thermally conductive particles as a dispersed phase.

[0017] In some such examples, the non-silicone polymer elastomer contains one or more of an epoxy-based matrix or a fluorocarbon-based matrix.

[0018] Additionally or alternatively, in some such examples, the thermally conductive particles comprise one or more of boron nitride, carbon fiber, graphite, aluminum oxide, or aluminum nitride.

[0019] Additionally or alternatively, in some such examples, the thermally conductive particles are electrically insulating.

[0020] Additionally or alternatively, in some such examples, the thermally conductive particles are electrically conductive.

[0021] Additionally or alternatively, in some such examples, the thermal interface component is configured to be located between the gas distribution plate and one or more of the inner and outer electrodes of the electrode assembly, wherein the gas distribution plate includes a plurality of gas distribution openings, and one or more of the thermal interface components include a plurality of holes positioned to match the gas distribution openings.

[0022] Additionally or alternatively, in some such examples, the thermal interface component includes a core layer sandwiched between a first thermal interface component layer and a second thermal interface component layer. Attached Figure Description

[0023] Figure 1 A schematic diagram showing an exemplary processing tool that includes a thermal interface component.

[0024] Figure 2 Show fit and Figure 1 A top view of an example of a thermal interface component used with processing tools.

[0025] Figure 3 show Figure 2 A cross-sectional view of the thermal interface component. Detailed Implementation

[0026] The term "additive" generally refers to a second material added to the continuous phase of a composite material during the manufacturing process. Additives can alter one or more properties of the continuous phase, such as viscosity, flexibility, electrical conductivity, or thermal conductivity.

[0027] The term "breakdown voltage" usually refers to the minimum voltage required for an insulating material to undergo electrical breakdown and become conductive.

[0028] The term "continuous phase" typically refers to the phase of a composite material in which solid or fluid particles of the dispersed phase (e.g., additives or fillers) are dispersed.

[0029] The term "dispersed phase" usually refers to a solid suspended within a continuous phase of a composite material.

[0030] The term “edge ring” typically refers to a component of a processing tool that is configured to surround a substrate positioned on a substrate support.

[0031] The term "elastomer" generally refers to a material that recovers its original shape after being stretched or compressed.

[0032] The term "electric conductor" and its variants generally refer to a material in which an electric current can flow without applying a voltage exceeding the material's band gap.

[0033] The terms "electrically insulator" and "electrically insulating" generally refer to materials with resistivity higher than that of semiconductors. The resistivity of electrically insulators can reach 10⁻⁶. 8 Ohms-centimeters or higher.

[0034] The term "electrode" generally refers to an electrical conductor located at a terminal of a conductive medium and used to make contact with the non-metallic part of a circuit.

[0035] The term "epoxy matrix" generally refers to a polymer matrix containing epoxy resin. Epoxy matrices may contain fibers and / or particles of one or more dispersed phase materials.

[0036] The term "fluorocarbon matrix" generally refers to a polymer matrix containing one or more compounds with carbon-fluorine bonds. Fluorocarbon matrix can contain fibers or particles and / or particles of one or more dispersed phase materials.

[0037] The term "gas distribution plate" typically refers to a component of an electrode assembly that receives a flow of process gas from a process gas inlet and distributes the process gas through one or more gas distribution openings.

[0038] The term "gasket" typically refers to a shaped material used to seal the interface between two or more components of a device.

[0039] The term "ligand" usually refers to the chemical component that binds to particles to functionalize the particle surface.

[0040] The term "plasma processing tool" generally refers to a machine that includes a processing chamber and other hardware configured to perform plasma processing within the processing chamber.

[0041] The term "relative permittivity" usually refers to the ratio of the dielectric constant of a material to the dielectric constant of vacuum.

[0042] The term "silicone polymer" typically refers to polymers whose main chain contains silicon-oxygen bonds. The term "non-silicone polymer" typically refers to polymers whose main chain does not contain silicon-oxygen bonds.

[0043] The term “substrate” generally refers to any object on which a thin film can be deposited.

[0044] The term “substrate support” generally refers to any structure configured to support a substrate in a processing chamber.

[0045] The term "thermal conductor" typically refers to a material that allows heat to pass through it at a rate of at least 1 W / (mK).

[0046] The term "thermally conductive particles" generally refers to particles of the dispersed phase in a composite material whose thermal conductivity is higher than that of the continuous phase of the composite material. "Thermally conductive particles" include or are made of "thermal conductors".

[0047] The term "thermal interface material" generally refers to a material used to conduct heat between two or more other components. The term "thermal interface component" generally refers to a gasket or other component that is at least partially made of thermal interface material.

[0048] As described above, a thermal interface material (TIM) is a thermally conductive component that can be placed between various parts of a processing tool to facilitate heat transfer between them. For example, in an etching or deposition tool, a thermal interface component can be placed between an electrode and a gas distribution plate. The gas distribution plate can be thermally coupled to other components to conduct heat away from the electrode. For instance, the thermal interface component between the gas distribution plate and the electrode can be selected to conduct heat at a sufficiently high rate to avoid inappropriate levels of thermal drift at the electrode during substrate processing. This thermal interface component can be electrically insulating, which facilitates segmented control of impedance on the electrode. This helps to achieve tunability of the plasma density on the substrate as a function of the electrode center-to-edge distance.

[0049] Some processing tools use silicone-based composite materials in their thermal interface components. Silicone-based composite materials comprise a silicone polymer (“silicone”) as the continuous phase and thermally conductive particles as the dispersed phase. The silicone polymer is an elastomer, and therefore, when placed between these components (e.g., gas distribution plates and electrodes), it can deform to conform to the surfaces of these components. This helps ensure good thermal contact between these components and the thermal interface component. Silicone is a durable material with a glass transition temperature suitable for plasma processing tools. The selected thermally conductive particles have a higher thermal conductivity than the silicone polymer. The thermal conductivity of this composite thermal interface component can be controlled by adjusting the size and / or density of the dispersed phase particles.

[0050] However, using silicone as the continuous phase can present several challenges in certain applications. For example, silicone can be degraded by hydrogen fluoride (HF), which can be used as an etchant in some etching processes. This can lead to premature aging of the thermal interface components. Aging affects the thermal conductivity and mechanical strength of the thermal interface components. Consequently, aging of the thermal interface components results in a shorter lifespan, requiring more frequent replacements than other related components, such as electrodes. Such replacements can cause tool downtime, severely impacting tool throughput. Silicone polymers also pose other risks, including silicone oil seepage, which can contaminate the processing tool and / or the substrate being processed within it.

[0051] Therefore, this paper discloses examples of thermal interface components employing a thermal interface material comprising a non-silicone polymer elastomer as a continuous phase and thermally conductive particles as a dispersed phase. Non-silicone polymer elastomers are more resistant to HF than silicone. Therefore, when used in HF-containing processing environments, the use of non-silicone polymer elastomers can prevent premature aging of the thermal interface components and avoid other problems associated with silicone-based thermal interface components. Non-silicone polymer elastomers may also exhibit better aging resistance in other processing chemical environments than in HF environments.

[0052] Before discussing these examples in more detail, Figure 1An exemplary processing tool 100, presented in the form of a plasma etching tool, is schematically shown. Figure 1 For informational purposes only. In other examples, the processing tool may include any other components suitable for performing plasma processes. Furthermore, in some examples, processing tool 100 may omit one or more of the components shown. While this document discusses plasma etching tools in the context of plasma etching tools, other processing tools may include thermal interface components according to the disclosed examples. Other examples of processing tools include plasma-enhanced atomic layer deposition (PEALD) and plasma-enhanced chemical vapor deposition (PECVD) tools.

[0053] Processing tool 100 includes a processing chamber 102. Processing tool 100 also includes a substrate holder 104 located within the processing chamber 102. During operation, a substrate 106 is disposed on the substrate holder 104. In some examples, the substrate holder 104 includes a base, an electrostatic chuck, and / or any other suitable components for supporting the substrate 106.

[0054] The processing tool 100 also includes an inner electrode 108 and an outer electrode 110. For example, using separate components of the inner electrode 108 and the outer electrode 110 instead of a single, larger electrode allows the inner electrode 108 and the outer electrode 110 to be replaced at different frequencies.

[0055] exist Figure 1 In this example, the inner electrode 108 and the outer electrode 110 are located below the process gas inlet 112 and the gas distribution plate 114. A substrate support 104 is configured to support the substrate 106 adjacent to the gas distribution plate 114. The gas distribution plate 114 receives a process gas flow from the process gas inlet 112. The process gas flow is distributed through one or more process gas flow channels (not shown) within the gas distribution plate 114. The gas distribution plate 114 also includes a plurality of gas distribution openings (not shown) leading from within the gas distribution plate 114 to corresponding plurality of holes (not shown) formed in the inner electrode 108 and the outer electrode 110. This allows the process gas to reach the substrate 106.

[0056] A first thermal interface component 170 is located between the gas distribution plate 114 and the inner electrode 108 and the outer electrode 110. The configuration of the first thermal interface component 170 facilitates the conduction of heat away from the inner electrode 108 and / or the outer electrode 110 during substrate processing. This helps, for example, prevent inappropriate temperature drift during substrate processing. The thermal interface component 170 includes a plurality of holes ( Figure 1 (Not shown in the image), the positions of these holes are complementary to the gas distribution openings of the gas distribution plate 114, and they act as conduits between the plurality of gas distribution openings of the gas distribution plate 114 and the plurality of holes of the inner electrode 108 and the outer electrode 110. An exemplary implementation of the thermal interface component 170 will be described in more detail below.

[0057] The substrate support 104 includes a conductive base plate 116 serving as a lower electrode. In some examples, such as systems for etching conductive materials, the conductive base plate 116 supports a substrate heater 120. If a substrate heater 120 is included, it may be in the form of a ceramic multi-zone heating plate. In other examples, such as systems for etching dielectric materials, the substrate heater may be omitted because the plasma heat may be very high, requiring cooling to maintain the substrate temperature. A thermally resistive layer 122 is disposed between the substrate heater 120 and the conductive base plate 116. The conductive base plate 116 includes one or more coolant channels 124 for allowing coolant to flow through it. The substrate support 104 also includes an edge ring 126 surrounding the substrate 106.

[0058] The processing tool 100 also includes a plasma generator 128 for generating plasma in the processing chamber 102. The plasma generator 128 generates and outputs a radio frequency (RF) voltage to the inner electrode 108 and the outer electrode 110. In some examples, the RF voltage oscillates around a bias voltage. The conductive base plate 116 may be DC grounded, AC grounded, or floating. The plasma generator 128 includes an RF voltage generator 130 configured to generate the RF voltage. The RF voltage is applied to the inner electrode 108 and the outer electrode 110 via an impedance matching and distribution network 132 to form plasma. In other examples, the RF voltage may be sent to the conductive base plate 116, and the inner electrode 108 and the outer electrode 110 may be DC grounded, AC grounded, or floating.

[0059] The treatment device 100 also includes a treatment chemical delivery system 134. The treatment chemical delivery system 134 includes treatment chemical sources 136A-136N (collectively referred to as treatment chemical sources 136), where N represents any number of additional treatment chemical sources equal to or greater than zero.

[0060] The processing device 100 also includes flow control hardware 138. The flow control hardware 138 is configured to control the flow rate of one or more processing chemicals flowing into the processing chamber 102. Each processing chemical source 136 is in fluid communication with the flow control hardware 138. For example, the processing chemical source 136 is connected to a manifold 144 via valves 140A-140N (collectively referred to as valves 140) and mass flow controllers (MFCs) 142A-142N (collectively referred to as MFC 142). The output of manifold 144 is delivered to the processing chamber 102, for example via a gas distribution plate 114 and internal and external electrodes 108, 110. The processing chemical delivery system 134 also helps control the pressure in the processing chamber 102.

[0061] Temperature controller 146 is connected to a plurality of thermally controlled elements (TCEs) 148 (e.g., heating elements) arranged in the ceramic layer 118. Temperature controller 146 controls the TCEs 148, thereby controlling the temperature of substrate support 104 and substrate 106. Furthermore, temperature controller 146 is in communication with coolant assembly 150 to control coolant flow through coolant channel 124. In some examples, coolant assembly 150 may include a coolant pump and a reservoir. Temperature controller 146 operates coolant assembly 150 to selectively flow coolant through coolant channel 124, thereby cooling substrate support 104.

[0062] Valve 152 and pump 154 ​​are used to evacuate reactants from processing chamber 102. Furthermore, system controller 156 is configured to control components of plasma processing tool 100. Robot 158 ​​transfers substrates onto and removes substrates from substrate holder 104. For example, robot 158 ​​transfers substrates between substrate holder 104 and loading lock 160. Although shown as different controllers, temperature controller 146 can be implemented within system controller 156. Additionally, a protective seal 162 is provided around the thermal resistance layer 122 between ceramic layer 118 and conductive base plate 116. In other examples, protective seal 162 is omitted.

[0063] Processing chamber 102 also includes a plasma confinement shroud 164. The plasma confinement shroud 164 is arranged around the outer electrode 110 and the edge ring 126. In the illustrated example, the inner electrode 108, outer electrode 110, plasma confinement shroud 164, and edge ring 126 confine the plasma within a plasma confinement region 166. In some examples, the plasma confinement shroud 164 is electrically connected to the outer electrode 110 and the inner electrode 108. The plasma confinement shroud 164 includes one or more slots 168 to provide fluid communication between the plasma confinement region 166 and the external environment of the plasma confinement shroud 164. In other examples, any other suitable plasma exposure component may be used to confine the plasma within the plasma confinement region.

[0064] Processing tool 100 includes various thermal interface components. As described above, processing tool 100 includes a first thermal interface component 170 located between gas distribution plate 114 and inner electrode 108 and outer electrode 110. In the illustrated example, processing tool 100 also includes a second thermal interface component 172 located between edge ring 126 and substrate support 104. Both thermal interface components 170 and 172 are used to remove heat generated during substrate processing. In some examples, the first thermal interface component 170 is used to maintain an appropriate and uniform temperature at inner electrode 108, which helps maintain uniformity in substrate etching. The second thermal interface component 172 is used to maintain an appropriate and uniform temperature at edge ring 126 during substrate processing without inappropriate temperature drift. This, in turn, helps maintain etching performance at the wafer edges. Thermocouples (not shown) inside or near inner electrode 108, outer electrode 110, and edge ring 126 can be used to monitor temperature during substrate processing. In other examples, the processing tool may include additional and / or alternative thermal interface components besides the first thermal interface component 170 and the second thermal interface component 172. During conductor substrate processing, both the first thermal interface component 170 and the second thermal interface component 172 are exposed to HF. Therefore, the first thermal interface component 170 and the second thermal interface component 172 may be susceptible to performance degradation due to HF.

[0065] Figure 2 A top-down schematic diagram showing an exemplary implementation of an exemplary thermal interface component 200. The thermal interface component 200 is suitable for, for example... Figure 1 The first thermal interface component 170 is located in the thermal interface component 200. Figure 1 The gas distribution plate 114 of the processing tool 100 is between the inner electrode 108 and the outer electrode 110. In this example, the thermal interface component 200 includes an inner gasket 202 and an outer gasket 204, but in other examples, the thermal interface component 200 may include a single integral gasket. For example, the inner gasket 202 may be aligned with the inner electrode 108, and the outer gasket 204 may be aligned with the outer electrode 110.

[0066] The thermal interface component 200 includes a plurality of holes 206 containing through-holes for the processed gas. The holes 206 are aligned and matched with the gas distribution openings of the aforementioned gas distribution plate 114 and the gas processing outlet holes of the inner electrode 108 and the outer electrode 110. This allows the processed gas to reach the interior of the processing chamber. In this example, the holes 206 are depicted as circular openings, but other shapes are also possible. The comparison of the diameter of the holes 206 to the diameter of the thermal interface component 200 is for reference only. The thermal interface component 200 may also include additional mounting holes 208 for securing the thermal interface component 200 to one or more of the gas distribution plate, the inner electrode, and the outer electrode. Additionally or alternatively, in some examples, the thermal interface component 200 may be secured in place on one or both sides using adhesive.

[0067] Figure 3 Showing Figure 2 A partially enlarged cross-sectional view of the heat interface component 200, along which... Figure 2 The enlarged segment 210 is cut from line 3-3. Figure 2 and Figure 3 This drawing is not to scale, but rather at an arbitrary scale to clearly illustrate the exemplary structure. In the illustrated example, the thermal interface component 200 includes a core layer 214 sandwiched between a first thermal interface component layer 216 and a second thermal interface component layer 218. However, in other examples, the core layer may be omitted, and the thermal interface component may comprise a single layer. For example, a thermal interface component comprising dispersed phase ceramic particles may not include a core layer. If a core layer 214 is included, it includes holes aligned with the holes 206 of the thermal interface component 200. However, laminating the core layer 214, the first thermal interface component layer 216, and the second thermal interface component layer 218 may introduce some offset between the layers, for example, in some examples, the offset is in the range of <1 mm.

[0068] Core layer 214 is configured to reinforce thermal interface component 200. This provides greater mechanical integrity than an unreinforced thermal interface component. Furthermore, the reinforced thermal interface component is easier to handle during installation and more easily aligned in processing tools compared to unreinforced material. For example, the tensile strength and / or Young's modulus of core layer 214 may be higher than that of the first thermal interface component layer 216 and the second thermal interface component layer 218. In some examples, the tensile strength and / or Young's modulus of core layer 214 is at least 25% higher than that of the first thermal interface component layer 216 and the second thermal interface component layer 218. More specifically, in some such examples, the tensile strength and / or Young's modulus of core layer 214 is at least 50% higher than that of the first thermal interface component layer 216 and the second thermal interface component layer 218.

[0069] Furthermore, the core layer 214 can be used to modify one or more other properties of the thermal interface component 200 (e.g., mechanical integrity, thermal conductivity, electrical conductivity, electrical insulation) while protecting it from the effects of the processing environment by the body material of the thermal interface. For example, the core layer can be a conductive foil. In some such examples, the core layer 214 comprises a metal, such as aluminum (e.g., an aluminum alloy) or any other suitable metal. Other examples comprise titanium and titanium alloys. In other examples, the core layer 214 can be an electrically insulating material, such as a polymer (e.g., polyimide). It should also be understood that the first thermal interface component 170 can be reinforced by any other suitable material (e.g., ceramic, polymer, or composite material). In some examples, two or more reinforcing layers (e.g., the core layer 214) can be used. In some such examples, the reinforcing layers may or may not be separated by thermal interface component layers.

[0070] The thermal interface component 200 has a thickness of 300. In some examples, the thickness 300 ranges from 100µm to 3mm. In some more specific examples, the thickness 300 ranges from 150µm to 1mm. In some more specific examples, the thickness 300 is greater than 400µm, for example, in the range of 400µm to 750µm. It should also be understood that in other examples, the thickness 300 can have any other suitable value. For example, when the thermal interface component 200 is a conductive thermal interface component, the thickness 300 can range from 100µm to 400µm, or, in some more specific examples, the thickness 300 can range from 200µm to 300µm. Other suitable examples of average thickness values ​​include values ​​less than 100µm and values ​​greater than 3mm. In some examples, multiple thinner thermal interface components can be stacked to form a thicker thermal interface component. For example, two or three thermal interface components with a thickness of 0.2 mm can be stacked to form thermal interface components with thicknesses of 0.4 mm or 0.6 mm, respectively. To maintain the thermal performance of thermal interface component 200 (if included), the core layer 214 can be thinner than the first thermal interface component layer 216 and the second thermal interface component layer 218. For example, the thickness of the core layer 214 can be in the range of 10-100 µm, or in some more specific examples, the thickness of the core layer 214 can be in the range of 20 to 50 µm. In other examples, the thickness of the core layer 214 can exceed these ranges.

[0071] A close-up of the second thermal interface component layer 218 is shown at position 310. Both the first thermal interface component layer 216 and the second thermal interface component layer 218 of the thermal interface component 200 contain a non-silicone polymer elastomer 312. The non-silicone polymer elastomer 312 is a continuous phase of the thermal interface component. In some examples, the non-silicone polymer elastomer 312 constitutes a majority or more than 50% of the volume of the thermal interface component.

[0072] In some examples, the gas permeability of the non-silicone polymer elastomer 312 is less than or equal to 20,000 cm⁻¹. 3 / m 2 / 24 hours. In some more specific examples, the gas permeability of the non-silicone polymer elastomer 312 is less than or equal to 2000 cm⁻¹. 3 / m 2 Within a 24-hour range. This helps slow down or prevent etchants such as HF from reaching and corroding the interior of thermal interface components, thus avoiding premature aging.

[0073] Non-silicone polymeric elastomer 312 can be based on a carbon-carbon backbone. In this way, non-silicone polymeric elastomer 312 is more resistant to HF erosion and aging than silicone-based backbones. In some examples, the elastomer continuous phase comprises one or more of the following materials: polyisoprene, butyl rubber, chloroprene, ethylpropylene diene, fluorocarbon matrix (e.g., fluororubber (FKM), perfluororubber (FFKM), nitrile rubber, saturated nitrile rubber, styrene-butadiene rubber, polyurethane, acrylic resin, or polyimide). In other examples, any other suitable polymer can be used. Other suitable polymer examples include natural rubber, polyolefins, epoxy-based matrices (e.g., with or without additives to impart elastomer properties), and polymer derivatives disclosed herein.

[0074] The thermal interface component 200 further includes a dispersed phase containing a thermal conductor. Figure 3 In some examples, the dispersed phase comprises multiple thermally conductive particles 314. In some examples, the thermal interface component 200 comprises up to 50% by weight of dispersed phase. In some more specific examples, the thermal interface component 200 comprises 10-49% by weight of dispersed phase. In even more specific examples, the thermal interface component 200 comprises 30-49% by weight of dispersed phase. It should be understood that the amount of dispersed phase can be selected based on the desired thermal conductivity, which is proportional to the concentration of dispersed phase in the thermal interface component. Furthermore, the amount of dispersed phase can also be additionally or selectively selected based on one or more characteristics of the thermal interface component, such as the viscosity of the continuous phase, the dispersibility of the coating particles, and the length of the polymer chains in the continuous phase.

[0075] In some examples, the thermally conductive particles 314 are electrically insulating particles. For example, the thermally conductive particles 314 may comprise materials such as oxides (e.g., aluminum oxides), nitrides (e.g., boron nitrides, aluminum nitrides), or other ceramics. In other examples, the thermally conductive particles 314 are electrically conductive particles. For example, in some plasma processing tools, the upper electrode is grounded, and it may be desirable for the thermal interface component to be both conductive and HF resistant. In these examples, the thermally conductive particles 314 may comprise metals, carbon (e.g., carbon fibers, graphite flakes), etc. In some examples, the thermally conductive particles 314 may comprise a mixture of two or more particle components. In these examples, the thermally conductive particles 314 may comprise a mixture of electrically insulating particles and conductive particles (e.g., carbon fibers and aluminum oxides) to produce the desired characteristics of the thermal interface component (e.g., a thermal interface component with relatively low capacitance / relatively high impedance).

[0076] In some examples, the thermally conductive particle 314 can be a coated particle comprising a core material and a different coating material (e.g., coating 316). For example, aluminum nitride particles coated with aluminum oxide can be used. Aluminum nitrides have ideal electrical and thermal conductivity but are difficult to disperse in non-silicone polymer elastomers. Furthermore, aluminum nitrides are prone to degradation when exposed to moisture or other compounds in semiconductor processing environments. In contrast, aluminum oxides are more robust under such conditions. Therefore, by coating the particles, particles containing materials with ideal electrical and / or thermal conductivity can be used even if the material is chemically incompatible with the processing environment.

[0077] In some examples, the dispersed phase particles can be functionalized with ligands. These ligands contain a chemical moiety that binds to the coated particles, thereby functionalizing the surface of the coated particles. The ligands can be crosslinked with non-silicone polymers, thereby immobilizing the particles within a continuous phase matrix.

[0078] In some examples, the core diameter of the thermally conductive particles 314 ranges from 1 to 100 µm. In some more specific examples, the core diameter ranges from 1 to 50 µm. In even more specific examples, the core diameter ranges from 1 to 10 µm. Larger particles disperse better in the continuous phase than smaller particles. Larger particles may also have a lower risk of agglomeration. However, smaller particles flow more easily than larger particles. It should also be understood that the core diameter can be selected based on the thickness of the thermal interface component. For example, a core size smaller than the thickness of the thermal interface component can be selected to ensure that the dispersed phase can be dispersed within the thermal interface component.

[0079] The thermal interface components disclosed herein help avoid inappropriate thermal changes or drift during substrate processing. In some examples, thermal changes can be quantified by the temperature change (ΔT) on the thermal interface component. For example, a gas distribution plate can be thermally connected to a heat sink set to a fixed temperature (e.g., 110°C). Thermocouples can be used to measure the temperature of the inner and / or outer electrodes. Therefore, in several examples, the temperature difference on the thermal interface component and between the inner and outer electrodes can be measured. Temperature non-uniformity can manifest as a higher-than-expected temperature difference on the thermal interface component, a higher-than-expected temperature difference between the inner and outer electrodes, and / or a higher-than-expected change in one or both temperature differences over time.

[0080] The thermal interface components disclosed herein may have appropriate thermal conductivity to conduct heat between two or more other components of a processing tool. Thermal conductivity may be quantified according to ASTM D 5470, a standard developed by ASTM International. In some examples, thermal conductivity is in the range of 1–50 W / mK. In some more specific examples, thermal conductivity is in the range of 2–40 W / mK. In even more specific examples, thermal conductivity is in the range of 2–5 W / mK. It should also be understood that thermal conductivity may have any other suitable value. Other examples of suitable thermal conductivity values ​​include values ​​less than 1 W / mK and values ​​greater than 10 W / mK. Similarly, the thermal interface components disclosed herein may have appropriate thermal resistance to conduct heat between two or more other components of a processing tool. In some examples, thermal resistance is in the range of 0.01–0.2 K / W.

[0081] The heat-sealing components disclosed herein may have suitable flexibility to form a seal between two or more other components of a processing tool. In some such examples, the Shore A hardness value of the heat-sealing components disclosed herein is in the range of 0-100. In some more specific examples, the Shore A hardness value is in the range of 60-100. In even more specific examples, the Shore A hardness value is in the range of 70-85. It should also be understood that harder or softer heat-sealing components may be used. Examples of other suitable heat-sealing components include materials softer than a Shore A hardness value of zero and materials harder than a Shore A hardness value of 100.

[0082] The thermal interface components disclosed herein may have suitable dielectric strength for use as electrical insulators. Dielectric strength may be quantified according to ASTM D 149, established by the American Society for Testing and Materials (ASTM International). In some examples, the dielectric strength is in the range of 1–100 kV / mm. In some more specific examples, the dielectric strength is in the range of 10–20 kV / mm. In even more specific examples, the dielectric strength is in the range of 14–16 kV / mm. It should also be understood that the dielectric strength may have any other suitable value. Other examples of suitable dielectric strength values ​​include values ​​less than 1 kV / mm and values ​​greater than 100 kV / mm. Similarly, the thermal interface components disclosed herein may have suitable AC breakdown voltage. In some examples, the AC breakdown voltage is >2.0 kV. In some more specific examples, the AC breakdown voltage is >4.0 kV. Similarly, the thermal interface components disclosed herein may have suitable relative permittivity. In some examples, the relative permittivity is in the range of 1–5. In some more specific examples, the relative permittivity is in the range of 1.5–4.5. In even more specific examples, the relative permittivity is in the range of 2–4.

[0083] The heat-sealing components disclosed herein may have any suitable density. Density can be quantified according to ASTM D 611, as specified by ASTM International. In some examples, the density is in the range of 1-10 g / cm³. 3 Within a certain range. In some more specific examples, the density is 1-5 g / cm³. 3 Within a certain range. In more specific examples, the density is 1-3 g / cm³. 3 Within the range. Other suitable examples of thermal interface components may have a density of less than 1 g / cm³. 3 or greater than 10 g / cm 3 .

[0084] It should also be understood that the thermal interface components disclosed herein possess appropriate flammability to ensure safe use in processing equipment. Flammability can be quantified according to the UL94 standard set by Underwriters Laboratories, Northbrook, Illinois, USA. For example, the thermal interface components disclosed herein may have a V-0 or VTM-0 flammability rating. In some examples, the non-silicone polymer elastomer may contain one or more additives. For example, one or more additives may be used to modify the viscosity, flexibility, thermal conductivity, and electrical conductivity of the thermal interface component. In some examples, the non-silicone polymer elastomer contains silicone-based additives. For example, silicone materials may be used to impart flexibility or resistance to the thermal interface component.

[0085] The silicon content in non-silicone polymer elastomer 312 can be quantified by any suitable method. An example of a suitable method for determining silicon content is energy-dispersive X-ray spectroscopy (EDX), as described in ASTM standard no. F1375. In some examples, the silicon content of non-silicone polymer elastomer 312 is less than 5% (mass percentage). In some more specific examples, the silicon content of non-silicone polymer elastomer 312 is less than 2% (mass percentage). In even more specific examples, the silicon content of non-silicone polymer elastomer 312 is less than 1% (mass percentage). In this way, silicon can be used as an additive without significantly affecting the integrity of the thermal interface component.

[0086] The subject matter of this disclosure includes all novel and non-obvious combinations and sub-combinations of various processes, systems and configurations, as well as other features, functions, behaviors and / or characteristics disclosed herein, and any and all equivalent schemes thereof.

Claims

1. A plasma processing tool, comprising: The outer electrode surrounding the inner electrode; Gas distribution plate; A thermal interface component is located between the gas distribution plate and one or more of the inner electrode and the outer electrode, wherein the thermal interface component comprises a non-silicone polymer elastomer as a continuous phase and thermally conductive particles as a dispersed phase.

2. The plasma processing tool according to claim 1, wherein the gas distribution plate includes a plurality of gas distribution openings, and wherein the thermal interface component includes a plurality of holes positioned to match the gas distribution openings.

3. The plasma processing tool of claim 1, wherein the plasma processing tool includes an edge ring and further includes a second thermal interface component located between the edge ring and the substrate support.

4. The plasma processing tool according to claim 1, wherein the non-silicone polymer elastomer comprises one or more of an epoxy-based matrix or a fluorocarbon-based matrix.

5. The plasma processing tool according to claim 4, wherein the thickness of the thermal interface component is > 0.4 mm.

6. The plasma processing tool according to claim 4, wherein the alternating current (AC) breakdown voltage of the thermal interface component is >4.0 kV.

7. The plasma processing tool according to claim 4, wherein the thermal conductivity of the thermal interface component is in the range of 2.0 W / mK to 40 W / mK.

8. The plasma processing tool according to claim 4, wherein the relative permittivity of the thermal interface component is in the range of 2-4.

9. The plasma processing tool of claim 1, wherein the thermal interface component comprises a core layer sandwiched between a first thermal interface component layer and a second thermal interface component layer.

10. The plasma processing tool according to claim 1, wherein the thermally conductive particles are electrically insulating.

11. The plasma processing tool of claim 10, wherein the thermally conductive particles comprise boron nitride.

12. The plasma processing tool according to claim 1, wherein the thermally conductive particles are electrically conductive.

13. The plasma processing tool of claim 12, wherein the thermally conductive particles comprise carbon fibers.

14. A thermal interface component for an electrode assembly of a plasma processing tool, the thermal interface component comprising: Non-silicone polymer elastomers as a continuous phase; and Thermally conductive particles as the dispersed phase.

15. The thermal interface component of claim 14, wherein the non-silicone polymer elastomer comprises one or more of an epoxy-based matrix or a fluorocarbon-based matrix.

16. The thermal interface component according to claim 15, wherein the thermally conductive particles comprise one or more of boron nitride, carbon fiber, graphite, aluminum oxide, or aluminum nitride.

17. The thermal interface component of claim 14, wherein the thermally conductive particles are electrically insulating.

18. The thermal interface component of claim 14, wherein the thermally conductive particles are conductive.

19. The thermal interface component of claim 14, wherein the thermal interface component is configured to be located between a gas distribution plate and one or more of the inner and outer electrodes of the electrode assembly, wherein the gas distribution plate includes a plurality of gas distribution openings, and wherein the one or more thermal interface components include a plurality of holes positioned to match the gas distribution openings.

20. The thermal interface component of claim 14, wherein the thermal interface component comprises a core layer sandwiched between a first thermal interface component layer and a second thermal interface component layer.

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