Porous Plug Joint

Abstract

[0003] The embodiments described herein generally relate to a porous plug having a sealing layer for use in a substrate support pedestal, and a method for forming the same. In one or more embodiments, the sealing layer can be formed in situ by applying a fluoroelastomer composition to at least one of the porous plug and a wall of a cavity of an electrostatic chuck. The fluoroelastomer composition can be cured in situ to form a sealing layer between the porous plug and the wall of the cavity. The porous plug is positioned within the cavity to control the flow of gas through the gas flow path. The sealing layer is positioned adjacent to the porous plug and can form one or more of a radial seal between the porous plug and the wall of the cavity and an axial seal between the porous plug and a cooling base.

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE Implementations described herein relate generally to substrate support pedestals, and more particularly to substrate support pedestals having a porous plug coupled thereto and methods of coupling a porous plug to a substrate support pedestal. [Background technology]

[0002] Substrate support pedestals are widely used to support substrates in semiconductor processing systems during processing. One particular type of substrate support pedestal includes a ceramic electrostatic chuck mounted on a cooled base. Electrostatic chucks generally hold the substrate in a stationary position during processing. Electrostatic chucks contain one or more embedded electrodes within a ceramic body. When a potential is applied between an electrode disposed on the ceramic body and the substrate, an electrostatic attractive force is generated, which holds the substrate against the support surface of the ceramic body. The generated force may have a capacitive effect due to the potential difference between the substrate and the electrode, or may have a Johnsen-Rahbek effect in the case of ceramic bodies composed of a semiconductor material with a relatively low resistivity that allows charge transfer within the ceramic body to a surface close to the substrate. Electrostatic chucks utilizing capacitive and Johnsen-Rahbek attractive forces are commercially available from several sources.

[0003] To control the substrate temperature during processing, a backside gas is provided between the support surface of the ceramic body and the substrate. Typically, the backside gas fills the interstitial region between the ceramic body and the substrate, thereby providing a heat transfer medium that enhances the rate of heat transfer between the substrate and the substrate support.

[0004] The bonding layer secures the electrostatic chuck to the cooling base. The bonding layer is susceptible to erosion by process gases passing through the bonding layer. Additionally, an eroded bonding layer may ignite, energize, or facilitate arcing in the portion of the backside gas channel through the substrate support pedestal that is exposed to the bonding layer. Bonding layer erosion is problematic for at least three reasons. First, material eroded from the bonding layer is a process contaminant that creates defects and reduces product yield. Second, as the size of the holes in the bonding layer through which the backside gas passes increases, the bonding material is replaced with gaps, changing the local heat transfer rate between the electrostatic chuck and the cooling base, thereby resulting in undesirable temperature non-uniformity and process drift. Third, an eroded bonding layer may provide a path from the substrate to ground potential along the sidewall.

[0005] Therefore, there is a need for an improved substrate support pedestal and method of fabricating the same. Summary of the Invention

[0006] FIELD OF THE DISCLOSURE Implementations described herein relate generally to substrate support pedestals, and more particularly to substrate support pedestals having a porous plug coupled thereto and methods of coupling a porous plug to a substrate support pedestal.

[0007] In one embodiment, a method of fabricating a chuck body is provided. The method includes coating a porous plug with a coating that includes a fluoroelastomer composition. The method further includes inserting the coated porous plug into a cavity defined by a wall formed in the chuck body. The method further includes curing the coating to form a sealing layer between the porous plug and the wall of the cavity.

[0008] The implementation may include one or more of the following: The coating has a thickness of about 25 microns to about 1,000 microns. The coating is partially cured to form a partially cured fluoroelastomer layer on the porous plug prior to inserting the porous plug. The sealing layer forms a radial seal between the porous plug and a wall of the cavity. The sealing layer further forms an axial seal between the porous plug and a cooling base coupled to the chuck body. The sealing layer further forms an axial seal between a top surface of the porous plug and a second wall of the cavity. The porous plug has a cylindrical or T-shape. The fluoroelastomer composition is a paste having a viscosity of about 50 cP to about 5,000 cP. The fluoroelastomer composition includes at least one perfluoropolymer. The fluoroelastomer composition further includes at least one of a curing agent, an adhesion promoter, a thickener, a solvent, and a filler.

[0009] In another aspect, a method of fabricating a chuck body is provided. The method includes coating a wall of a cavity formed in the chuck body with a coating including a fluoroelastomer composition. The method further includes inserting a porous plug into the cavity. The method further includes curing the coating to form a sealing layer between the porous plug and the wall of the cavity.

[0010] The implementation may include one or more of the following: the coating has a thickness of about 25 microns to about 1,000 microns; the coating is partially cured to form a partially cured fluoroelastomer layer on the wall of the cavity prior to inserting the porous plug; the sealing layer forms a radial seal between the porous plug and the wall of the cavity; the sealing layer further forms an axial seal between the porous plug and a cooling base coupled to the chuck body; the sealing layer further forms an axial seal between a top surface of the porous plug and a second wall of the cavity; the porous plug has a cylindrical or T-shape; the fluoroelastomer composition is a paste having a viscosity of about 50 cP to about 5,000 cP; the fluoroelastomer composition includes at least one perfluoropolymer; the fluoroelastomer composition further includes at least one of a curing agent, an adhesion promoter, a thickener, a solvent, and a filler.

[0011] In yet another aspect, a method of fabricating a chuck body is provided. The method includes coating a porous plug with a first coating comprising a fluoroelastomer composition. The method further includes coating a wall of a cavity formed in the chuck body with a second coating comprising the fluoroelastomer composition. The method further includes inserting the porous plug with the first coating formed thereon into the cavity with the second coating formed thereon. The method further includes curing the first coating and the second coating to form a sealing layer between the porous plug and the wall of the cavity.

[0012] The implementation may include one or more of the following: prior to inserting the porous plug, at least one of the first coating and the second coating is partially cured to form a partially cured fluoroelastomer layer on at least one of the porous plug and the wall of the cavity; at least one of the first coating and the second coating has a thickness of about 25 microns to about 1,000 microns; the sealing layer further forms a radial seal between the porous plug and the wall of the cavity; the sealing layer further forms an axial seal between the porous plug and a cooling base coupled to the chuck body; the sealing layer further forms an axial seal between a top surface of the porous plug and a second wall of the cavity; the porous plug has a cylindrical or T-shape; the fluoroelastomer composition is a paste having a viscosity of about 50 cP to about 5,000 cP; the fluoroelastomer composition includes at least one perfluoropolymer. The fluoroelastomer composition further comprises at least one of a curing agent, an adhesion promoter, a thickener, a solvent, and a filler.

[0013] In another aspect, a method of fabricating a chuck body is provided. The method includes coating a porous plug with a coating that includes a fluoroelastomer composition. The method further includes curing the coating to form a sealing layer on the porous plug. The method further includes inserting the porous plug with the sealing layer formed thereon into a cavity in the chuck body having a wall, where the sealing layer is compressed to form a seal between the wall of the cavity and the porous plug.

[0014] The implementation may include one or more of the following: The coating has a thickness of about 25 microns to about 1,000 microns. The sealing layer forms a radial seal between the porous plug and a wall of the cavity. The sealing layer further forms an axial seal between the porous plug and a cooling base coupled to the chuck body. The sealing layer further forms an axial seal between a top surface of the porous plug and a second wall of the cavity. The porous plug has a cylindrical or T-shape. The fluoroelastomer composition is a paste having a viscosity of about 50 cP to about 5,000 cP. The fluoroelastomer composition includes at least one perfluoropolymer. The fluoroelastomer composition further includes at least one of a curing agent, an adhesion promoter, a thickener, a solvent, and a filler.

[0015] In yet another aspect, a method of fabricating a chuck body is provided. The method includes coating a wall of a cavity formed in the chuck body with a first coating including a fluoroelastomer composition. The method further includes curing the coating to form a sealing layer on the wall of the cavity. The method further includes inserting a porous plug into the cavity with the sealing layer formed therein, the sealing layer being compressed to form a seal between the wall of the cavity and the porous plug.

[0016] Implementations may include one or more of the following potential advantages: The coating has a thickness of about 25 microns to about 1,000 microns. The sealing layer forms a radial seal between the porous plug and a wall of the cavity. The sealing layer further forms an axial seal between the porous plug and a cooling base coupled to the chuck body. The sealing layer further forms an axial seal between a top surface of the porous plug and a second wall of the cavity. The porous plug has a cylindrical or T-shape. The fluoroelastomer composition is a paste having a viscosity of about 50 cP to about 5,000 cP. The fluoroelastomer composition includes at least one perfluoropolymer. The fluoroelastomer composition further includes at least one of a curing agent, an adhesion promoter, a thickener, a solvent, and a filler.

[0017] In yet another aspect, a method of fabricating a chuck body is provided. The method includes coating a porous plug with a first coating comprising a fluoroelastomer composition. The method further includes partially curing the first coating to form a first partially cured sealing layer on the porous plug. The method further includes coating a wall of a cavity formed in the chuck body with a second coating comprising the fluoroelastomer composition. The method further includes inserting the porous plug with the first partially cured sealing layer formed thereon into the cavity with the second coating formed thereon. The method further includes curing the first partially cured sealing layer and the second coating to form a sealing layer between the porous plug and the wall of the cavity.

[0018] Implementations may include one or more of the following potential advantages: At least one of the first coating and the second coating has a thickness of about 25 microns to about 1,000 microns. The sealing layer forms a radial seal between the porous plug and a wall of the cavity. The sealing layer further forms an axial seal between the porous plug and a cooling base coupled to the chuck body. The sealing layer further forms an axial seal between a top surface of the porous plug and a second wall of the cavity. The porous plug has a cylindrical or T-shape. The fluoroelastomer composition is a paste having a viscosity of about 50 cP to about 5,000 cP. The fluoroelastomer composition includes at least one perfluoropolymer. The fluoroelastomer composition further includes at least one of a curing agent, an adhesion promoter, a thickener, a solvent, and a filler.

[0019] In yet another aspect, a non-transitory computer-readable medium stores instructions that, when executed by a processor, cause the processor to perform the apparatus operations and / or methods described above.

[0020] So that the above-mentioned features of the present disclosure can be understood in detail, a more particular description of the implementations briefly summarized above may be had with reference to the implementations, some of which are illustrated in the accompanying drawings. It should be noted, however, that since the present disclosure may admit of other equally effective implementations, the accompanying drawings depict only typical implementations of the present disclosure and therefore should not be considered as limiting the scope of the present disclosure. [Brief description of the drawings]

[0021] [Figure 1] 1 is a schematic diagram of a process chamber including a substrate support pedestal having a bonded porous plug in accordance with one or more implementations of the present disclosure. [Diagram 2] 1 illustrates a partial cross-sectional view of a substrate support pedestal having a bonded porous plug in accordance with one or more implementations of the present disclosure. [Diagram 3] 1 illustrates a partial cross-sectional view of a substrate support pedestal having a bonded porous plug in accordance with one or more implementations of the present disclosure. [Figure 4] 1 is a flowchart of one example method of forming a substrate pedestal having an associated porous plug in accordance with one or more implementations of the present disclosure. [Diagram 5] 13 is a flowchart of another example method of forming a substrate pedestal having an associated porous plug in accordance with one or more implementations of the present disclosure. [Figure 6] 13 is a flowchart of yet another example method of forming a substrate pedestal having an associated porous plug in accordance with one or more implementations of the present disclosure. [Figure 7] 13 is a flowchart of yet another example method of forming a substrate pedestal having an associated porous plug in accordance with one or more implementations of the present disclosure. [Figure 8] 13 is a flowchart of yet another example method of forming a substrate pedestal having an associated porous plug in accordance with one or more implementations of the present disclosure. [Figure 9A]1A-1C are schematic cross-sectional views of forming a substrate pedestal having a bonded porous plug in accordance with one or more implementations of the present disclosure. [Figure 9B] 1A-1C are schematic cross-sectional views of forming a substrate pedestal having a bonded porous plug in accordance with one or more implementations of the present disclosure. [Figure 9C] 1A-1C are schematic cross-sectional views of forming a substrate pedestal having a bonded porous plug in accordance with one or more implementations of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] For ease of understanding, wherever possible, identical reference numbers have been used to designate identical elements that are common to the figures. It is contemplated that elements and features of one implementation may be beneficially incorporated in other implementations without further recitation.

[0023] The following disclosure describes bonded porous plugs and methods for forming bonded porous plugs. Certain details are described in the following description and in Figures 1-9C to provide a thorough understanding of various implementations of the present disclosure. Other details describing well-known structures and systems often associated with the formation of bonded porous plugs and elastomeric polymers are not described in the following disclosure to avoid unnecessarily obscuring the description of various implementations. Additionally, the descriptions of the devices described herein are exemplary and should not be taken or interpreted as limiting the scope of the implementations described herein.

[0024] Many of the details, dimensions, angles, and other features shown in the figures are merely illustrative of particular implementations. Thus, other implementations can have other details, components, dimensions, angles, and features without departing from the spirit or scope of the present disclosure. Moreover, further implementations of the present disclosure can be practiced without some of the details described below.

[0025] The porous plug is used by the electrostatic chuck to allow backside gas to reach and cool a substrate positioned on the electrostatic chuck, while preventing process gas from traveling downward through the electrostatic chuck. One method for bonding the porous plug to the electrostatic chuck includes using silicone to bond the porous plug to the electrostatic chuck. However, a potential problem with silicone is that the silicone forms bonds with fluorine from the fluorine process gas. This fluorine can result in undesirable arcing from the substrate to ground through a bonding layer of fluorine contamination. Thus, it would be advantageous to have a bonding material for the porous plug and a method for bonding the porous plug that reduces or prevents undesirable arcing.

[0026] The systems and methods discussed herein use a substrate support pedestal having a cooling base and an electrostatic chuck bonded together by a bonding layer. A porous plug is positioned in a gas flow passage formed in the cooling base and the electrostatic chuck. The porous plug is bonded to the electrostatic chuck using a sealing layer formed from a fluoroelastomer composition. The sealing layer, in combination with the porous plug, protects the bonding layer from process gases utilized during processing of the substrate. Advantageously, the following implementations discuss improved techniques for preventing degradation of the bonding layer through the utilization of a sealing layer that secures the porous plug in the gas flow passage and substantially prevents gas from flowing around the porous plug. Additionally, the sealing layer is constructed of a fluorine-resistant material. This is an improvement over the silicone materials used to bond the porous plug to the electrostatic chuck. These silicone materials are susceptible to fluorine contamination from the process gases, which can result in arcing from the semiconductor substrate through the fluorine-contaminated silicone material to ground. Additionally, the fluoroelastomer composition can be applied as a viscosity modifier. Additionally, sealing layers formed from fluoroelastomer compositions can withstand greater temperatures than silicone compounds.

[0027] As used herein, "fluoroelastomer composition" refers to a polymeric composition that includes a curable fluoropolymer. The fluoropolymer may be formed by polymerizing two or more monomers, preferably one of which is fluorinated or perfluorinated, and at least one of which is a cure site monomer that allows for curing, such as at least one fluoropolymer cure site monomer. The fluoroelastomer composition described herein may include any suitable curable fluoroelastomer fluoropolymer (FKM) or perfluoroelastomer fluoropolymer (FFKM) that can be cured to form a fluoroelastomer or perfluoropolymer, and one or more curing agents as described herein.

[0028] Perfluoroelastomer as used herein may be any substantially cured elastomeric material obtained by curing a perfluoropolymer (as defined herein) having at least one crosslinking group that allows the curing to be provided by at least one cure site monomer. Perfluoropolymer as used herein is substantially fluorinated, preferably fully fluorinated, with respect to the carbon atoms on the backbone of the perfluoropolymer. It will be understood that due to the use of hydrogen in the functional crosslinking group in some perfluoroelastomer formulations, some residual hydrogen may be present in the perfluoroelastomer within the crosslinks.

[0029] Fluoroelastomer and perfluoroelastomer compositions, also known as fluorocarbon elastomers, as used herein, may be cured or uncured (curable). When modified by the terms "uncured" or "curable", a fluoroelastomer or perfluoroelastomer composition refers to a composition that contains a fluoropolymer or perfluoropolymer, but where such crosslinking has not yet substantially occurred, making the material unsuitable for its intended use.

[0030] The fluoroelastomer compositions described herein may contain several different components, such as one or more fluoropolymers, one or more perfluoropolymers with various cure sites, curing agents, adhesion promoters, thickeners, solvents, and a number of other optional fillers and additives, in various permutations as described in detail below.

[0031] In some implementations, the curable elastomeric perfluoropolymer can include two or more different perfluorinated copolymers, at least one of which is a perfluoroalkyl vinyl ether (PAVE) that includes a fluorine-containing ethylenically unsaturated monomer, such as tetrafluoroethylene (TFE), a perfluorinated olefin, such as hexafluoropropylene (HFP), and an alkyl group that is linear or branched and includes one or more ether linkages, such as perfluoro(methyl vinyl ether), perfluoro(ethyl vinyl ether), perfluoro(propyl vinyl ether), and similar compounds. Suitable examples of PAVE include perfluoro(methyl vinyl) ether (PMVE) and perfluoro(propyl vinyl) ether (PPVE). In one example, PAVE can be represented by the formula CF2=CFO(CF2CFXO) n R f wherein X is F or CF3, n is 0 to 5, and R fis a perfluoroalkyl group of 1 to 6 carbon atoms. Suitable perfluoropolymers may meet the industry-accepted definition of perfluoroelastomers listed as FFKM in ASTM D-1418, and may be terpolymers or tetrapolymers of TFE, PAVE, and may have one perfluorinated cure site monomer incorporating a functional group to enable crosslinking of the terpolymer, at least one of which is a cure site that can be cured by the cure system used in the practice of the present disclosure. These monomers may be used in conjunction with comonomers that facilitate crosslinking. Small concentrations of non-perfluorinated monomers may also be used. Typically, such monomers are used to obtain the desired crosslinking properties and may be present in concentrations of up to about 3 mole percent. Examples of such monomers include bromotetrafluorobutene, bromotrifluoroethylene, vinylidene fluoride, and nitrile group-containing monomers.

[0032] The fluoroelastomer composition of the present disclosure, in its uncured or curable state, can include at least one curing agent that corresponds to one of the at least one cure site monomers present on the fluoropolymer (e.g., capable of facilitating crosslinking of at least one cure site monomer). Any curing agent or combination of curing agents can be used. By way of example, peroxide cure systems or cyano cure systems can be used, depending on the desired end product and physical properties of the fluoroelastomer composition. Regardless of the cure system or combination of systems used, the fluoropolymer can contain at least one cure site monomer, although the presence of from about 2 to about 20 (same or different) cure site monomers may be desired. Any amount of curing agent may be present to provide adequate cure.

[0033] The fluoroelastomer composition may contain an acrylate compound, for example, any compound known or developed in the art that contains one or more functional acrylate groups. The acrylate compound may be a metal acrylate, or a combination of different acrylate compounds and / or metal acrylates. Examples may include diacrylate, methacrylate, dimethacrylate, triacrylate, and / or tetraacrylate compounds. More specifically, suitable examples may include zinc or copper diacrylates and methacrylates. Such compounds are known to be commercially available, for example, from Sartomer, Exton, Pennsylvania, USA (e.g., under the trade names SARET® SR633 and SARET® SR634). Also included are perfluoroelastomers, fluoroelastomers, elastomers, or other resins that contain acrylate groups incorporated into their structure.

[0034] The fluoroelastomer composition may also contain one or more additional additives, such as fillers, plasticizers, polymer blends, and colorants. Optionally, other additives may include, for example, carbon black, glass fiber, glass spheres, silicates, fiberglass, calcium sulfate, asbestos, boron fiber, ceramic fiber, aluminum hydroxide, barium sulfate, calcium carbonate, fluorographite, magnesium carbonate, alumina, aluminum nitride, borax, perlite, zinc terephthalate, silicon carbide platelets, wollastonite, calcium terephthalate, fullerene tubes, hectorite, talc, mica, carbon nanotubes, and silicon carbide whiskers.

[0035] The fluoroelastomer compositions discussed above may contain any or all of the various components discussed above in any proportion, ratio, or substitution. Those skilled in the art will recognize that such components and relative ratios may be changed and varied depending on the desired properties of the final product, which will be known by the application for which the combined components will be used.

[0036] Upon curing, the fluoroelastomer composition forms a sealing layer that also bonds the porous plug to the electrostatic chuck.

[0037] In some implementations of the present disclosure, the fluoroelastomer composition is bonded to the porous plug and / or electrostatic chuck by contacting a curable perfluoroelastomer composition (as described herein) to the porous plug and / or electrostatic chuck and curing it by any curing process known or developed in the art. In some implementations of the present disclosure, the fluoroelastomer composition is bonded to the porous plug and / or electrostatic chuck by contacting a curable perfluoroelastomer composition to the porous plug and / or electrostatic chuck and partially curing or semi-curing (e.g., some cross-linking may occur, but not to the desired extent). The porous plug and / or electrostatic chuck coated with the semi-cured fluoroelastomer composition can be contacted with another inert substrate and cured in situ to form a final fluoroelastomer sealing layer between the porous plug and the electrostatic chuck.

[0038] Curing or partially curing (e.g., semi-curing) in any manner may be accomplished by any process known or developed in the art, including heat curing, curing by application of high energy, heat curing, press curing, steam curing, pressure curing, electron beam curing, or any combination thereof. Post-curing treatments may also be applied, if desired.

[0039] In some implementations, the fluoroelastomer composition is applied as a paste. As used herein, "paste" refers to a heterogeneous composition having a viscosity of about 1 centipoise (cP) to about 10,000 cP. "Heterogeneous composition" refers to a composition having multiple excipients or components. As used herein, "paste" can also refer to gels, creams, glues, adhesives, and any other viscous liquid or semi-solid. In some implementations, pastes for use in the present disclosure have a tunable viscosity and / or a viscosity that is controllable by one or more external conditions.

[0040] In some implementations, the fluoroelastomer composition is in a paste form having a viscosity of about 1 cP to about 10,000 cP. In some implementations, the fluoroelastomer composition is in a paste form having a minimum viscosity of about 1 cP, about 2 cP, about 5 cP, about 10 cP, about 15 cP, about 20 cP, about 25 cP, about 30 cP, about 40 cP, about 50 cP, about 60 cP, about 75 cP, about 100 cP, about 125 cP, about 150 cP, about 175 cP, about 200 cP, about 250 cP, about 300 cP, about 400 cP, about 500 cP, about 750 cP, about 1,000 cP, about 1,250 cP, about 1,500 cP, or about 2,000 cP. In some implementations, the fluoroelastomer composition is pasty having a peak viscosity of about 10,000 cP, about 9,500 cP, about 9,000 cP, about 8,500 cP, about 8,000 cP, about 7,500 cP, about 7,000 cP, about 6,500 cP, about 6,000 cP, about 5,500 cP, about 5,000 cP, about 4,000 cP, about 3,000 cP, about 2,000 cP, about 1,000 cP, about 500 cP, about 250 cP, about 100 cP, or about 50 cP.

[0041] In some implementations, the fluoroelastomer composition has a viscosity of about 50 cP to about 5,000 cP, about 50 cP to about 4,000 cP, about 50 cP to about 3,000 cP, about 50 cP to about 2,000 cP, about 50 cP to about 1,000 cP, about 80 cP to about 500 cP, about 80 cP to about 450 cP, about 80 cP to about 400 cP, about 80 cP to about 300 cP, about 80 cP to about 250 cP, about 80 cP to about 200 cP, about 80 cP to about 150 cP, about 100 cP to about 1,00 The composition is in a paste form having a viscosity of 0 cP, about 100 cP to about 900 cP, about 100 cP to about 800 cP, about 100 cP to about 700 cP, about 100 cP to about 600 cP, about 100 cP to about 500 cP, about 100 cP to about 400 cP, about 100 cP to about 300 cP, about 100 cP to about 250 cP, about 200 cP to about 500 cP, about 200 cP to about 400 cP, about 250 cP to about 500 cP, about 300 cP to about 500 cP, or about 400 cP to about 500 cP.

[0042] Typically, the viscosity of the fluoroelastomer composition is controlled. In some implementations, the viscosity of the fluoroelastomer composition is adjusted based on the pore size of the pores formed in the porous plug. For example, the viscosity of the fluoroelastomer composition is adjusted so that the fluoroelastomer composition coats the surface of the porous plug 202 but does not fill the internal pores of the porous plug 202. Parameters that can control the viscosity of the fluoroelastomer composition include, but are not limited to, the average length, molecular weight, and / or degree of crosslinking of the copolymer, as well as the presence of a solvent and a concentration of the solvent, a thickener (i.e., a viscosity adjusting component) and a concentration of the thickener, the particle size of the components present in the paste, the free volume (i.e., porosity) of the components present in the paste, the swelling properties of the components present in the paste, the ionic interactions (e.g., solvent-thickener interactions) between oppositely charged and / or partially charged species present in the paste, or combinations thereof.

[0043] In some implementations where it is desirable to adjust the viscosity of the fluoroelastomer composition, the fluoroelastomer composition further comprises at least one of a solvent and a thickener. In some implementations, a combination of solvent and thickener can be selected to adjust the viscosity of the paste.

[0044] Suitable thickening agents for use in the fluoroelastomer compositions of the present disclosure include, but are not limited to, metal salts of carboxyalkylcellulose derivatives (e.g., sodium carboxymethylcellulose), alkylcellulose derivatives (e.g., methylcellulose and ethylcellulose), partially oxidized alkylcellulose derivatives (e.g., hydroxyethylcellulose, hydroxypropylcellulose, and hydroxypropylmethylcellulose), starch, polyacrylamide gels, homopolymers of poly-N-vinylpyrrolidone, poly(alkyl ethers) (e.g., polyethylene oxide and polypropylene oxide), agar, agarose, xanthan gum, gelatin, dendrimers, colloidal silicon dioxide, and combinations thereof. In some implementations, the thickening agent is present in the fluoroelastomer composition at a concentration of about 0.1 to about 50%, about 0.5 to about 25%, about 1 to about 20%, or about 5 to about 15% by weight of the paste.

[0045] In some implementations, the fluoroelastomer composition further comprises a solvent. Solvents suitable for use in the fluoroelastomer compositions of the present disclosure include water, C1-C8 alcohols (e.g., methanol, ethanol, propanol, and butanol), C6-C 12 Linear, branched and cyclic hydrocarbons (e.g., hexane and cyclohexane), C6-C 14 Aryl and aralkyl hydrocarbons (e.g., benzene and toluene), C3-C 10 Alkyl ketones (e.g., acetone), C3-C 10 Esters (e.g., ethyl acetate), C4-C 10In some implementations, the solvent is present in the paste at a concentration of about 10 to about 99% by weight. In some implementations, the solvent is present in the fluoroelastomer composition at a maximum concentration of about 99%, about 98%, about 97%, about 95%, about 90%, about 80%, about 70%, about 60%, about 50%, about 40%, or about 30% by weight of the paste. In some implementations, the solvent is present at a minimum concentration of about 15%, about 20%, about 25%, about 30%, about 40%, about 50%, about 60%, about 70%, or about 80% by weight of the fluoroelastomer composition.

[0046] In some implementations, vacuum venting is performed on the applied material and the coated part prior to curing to control porosity in the formed coating layer.

[0047] 1 shows a schematic diagram of a process chamber 100 including a substrate support pedestal 110 in accordance with one or more implementations of the present disclosure. The substrate support pedestal 110 includes a bonded porous plug as described herein. The process chamber 100 includes a chamber body 102 that defines a processing volume 104. The substrate support pedestal 110 is positioned within the processing volume 104. The chamber body 102 includes a ceiling 106, a bottom wall 107, and one or more chamber walls 108. The ceiling 106 can be composed of a dielectric material.

[0048] The substrate support pedestal 110 includes an electrostatic chuck 112 disposed on a cooling base 114. The electrostatic chuck 112 includes a bonded porous plug 200 as shown in FIG. 2 and FIG. 3. The porous plug 202 is bonded to the electrostatic chuck according to the methods described herein. The substrate support pedestal 110 is generally supported above a bottom wall 107 of the process chamber 100 by a shaft 116 coupled to the cooling base 114. The substrate support pedestal 110 is clipped to the shaft 116 such that the substrate support pedestal 110 is removable from the shaft 116, refurbishable, and reattachable to the shaft 116. The shaft 116 is sealed to the cooling base 114 to isolate the various conduits and leads disposed thereon from the process environment within the process chamber 100. Alternatively, the electrostatic chuck 112 and the cooling base 114 may be disposed on an insulating plate attached to a ground plate or chassis. Additionally, the ground plate may be attached to one or more of the ceiling 106, the bottom wall 107, and the one or more chamber walls 108.

[0049] The electrostatic chuck 112 includes a support surface 120 for supporting a substrate, e.g., a substrate 122, e.g., a semiconductor substrate. The temperature of the substrate 122 is controlled by stabilizing the temperature of the electrostatic chuck 112. For example, a backside gas (e.g., helium or other gas) may be provided by a gas source 124 to a plenum defined between the substrate 122 and the support surface 120 of the electrostatic chuck 112. The backside gas is used to facilitate heat transfer between the substrate 122 and the substrate support pedestal 110 to control the temperature of the substrate 122 during processing. The electrostatic chuck 112 may include one or more heaters. For example, the heater may be an electric heater, etc. The electrostatic chuck 112 may include one or more electrodes, which may be coupled to a power source 125.

[0050] The process chamber 100 further includes at least an inductive coil antenna segment 130A and a conductive coil antenna segment 130B, both of which are positioned outside the ceiling 106. The inductive coil antenna segment 130A and the conductive coil antenna segment 130B are each coupled to a radio frequency (RF) source 132 that produces an RF signal. The RF source 132 is coupled to the inductive coil antenna segment 130A and the conductive coil antenna segment 130B through a matching network 134. The substrate support pedestal 110 is also coupled to an RF source 136 that produces an RF signal. The RF source 136 is coupled to the substrate support pedestal 110 through a matching network 138. One or more chamber walls 108 are conductive and connected to a ground 140.

[0051] The pressure within the processing volume 104 of the process chamber 100 is controlled using a throttle valve 142 located between the process chamber 100 and a vacuum pump 144. The temperature at the surface of one or more chamber walls 108 is controlled using a liquid-containing conduit (not shown) installed in one or more chamber walls 108 of the process chamber 100.

[0052] A system controller 150 is coupled to various components of the process chamber 100 to facilitate control of the substrate processing process. The system controller 150 includes a memory 152, a central processing unit (CPU) 154, and support circuits (or I / O) 156. Software instructions and data can be coded and stored in the memory to instruct the CPU. The system controller 150 can communicate with one or more of the components of the process chamber 100, for example, via a system bus. A program (or computer instructions) readable by the system controller 150 determines which tasks can be performed on the substrate. In some embodiments, the program is software readable by the system controller 150. Although a single system controller 150 is shown, it should be understood that multiple system controllers can be used in the embodiments described herein.

[0053] During operation, a substrate 122 is placed on the support surface 120 of the substrate support pedestal 110, and gas components are supplied to the process chamber 100 from the gas panel 160 through the inlets 162 to form a gas mixture in the processing volume 104 of the process chamber 100. The gas mixture in the processing volume 104 is ignited into a plasma in the process chamber 100 by applying RF power from RF sources 132, 136 to the inductive coil antenna segment 130A, the conductive coil antenna segment 130B, respectively, and to the substrate support pedestal 110. Additionally, chemically reactive ions are emitted from the plasma and bombard the substrate 122, thereby removing exposed material from the surface of the substrate.

[0054] 2 is a partial cross-sectional view of a substrate support pedestal 110 having a bonded porous plug 200 in accordance with one or more implementations of the present disclosure. The bonded porous plug 200 includes a porous plug 202 and a sealing layer 204. As discussed above, the substrate support pedestal 110 includes a cooling base 114 secured to the electrostatic chuck 112 by a bonding layer 210.

[0055] Bonding layer 210 includes one or more materials, such as an acrylic or silicone based adhesive, an epoxy, a neoprene based adhesive, an optically clear adhesive such as a clear acrylic adhesive, or other suitable adhesive.

[0056] The cooling base 114 is generally fabricated from a metallic material, such as stainless steel, aluminum, aluminum alloys, among other suitable materials. Additionally, the cooling base 114 includes one or more cooling channels 212 disposed therein that circulate a heat transfer fluid to maintain thermal control of the substrate support pedestal 110 and the substrate 122.

[0057] The electrostatic chuck 112 is generally circular, but may alternatively include other geometries to accommodate non-circular substrates. For example, the electrostatic chuck 112 may include square or rectangular substrates when used to process display glass, such as glass for flat panel displays. The electrostatic chuck 112 generally includes a chuck body 214 that includes one or more electrodes 216. The electrodes 216 are constructed of conductive materials, such as copper, graphite, tungsten, and molybdenum. Various implementations of electrode structures include, but are not limited to, a pair of coplanar D-shaped electrodes, coplanar interdigitated electrodes, multiple coaxial annular electrodes, a single circular electrode, or other structures. The electrodes 216 are coupled to a power supply 125 by a feedthrough 218 disposed within the substrate support pedestal 110. The power supply 125 may drive the electrodes 216 with a positive or negative voltage. For example, the power supply 125 may drive the electrodes 216 with a voltage of about -1000 volts or a voltage of about 2500 volts. Alternatively, other negative or other positive voltages may be utilized.

[0058] The chuck body 214 of the electrostatic chuck 112 can be made of a ceramic material. For example, the chuck body 214 of the electrostatic chuck 112 can be made of a low resistivity ceramic material, e.g., a low resistivity ceramic material having a resistivity of about 1×E 9 From about 1×E 11The electrostatic chuck 112 may be fabricated from a material having a resistivity between 1×E ohms cm. Examples of low resistivity materials include ceramics such as alumina doped with titanium oxide or chromium oxide, doped aluminum oxide, doped boron nitride, and the like. Other materials of comparable resistivity may also be used, such as aluminum nitride. Such ceramic materials, having a relatively low resistivity, generally facilitate a Johnsen-Rahbek attractive force between the substrate and the electrostatic chuck 112 when power is applied to the electrode 216. Alternatively, a 1×E 2 ceramic material may be fabricated from a material having a resistivity between 1×E 2 ... 11 A chuck body 214 including a ceramic material having a resistivity of ohm-cm or higher may also be used. Additionally, the chuck body 214 of the electrostatic chuck 112 may be fabricated from aluminum oxide, which can have a high resistivity and can be used in Coulombic mode.

[0059] In operation, an electric field generated by actuating the electrodes 216 holds the substrate 122 on the support surface 120 with a clamping force.

[0060] A backside gas, e.g., helium, nitrogen, or argon, is introduced by a gas source 124 into one or more gas flow passages 230 to help control the temperature of the substrate 122 as it is held by the electrostatic chuck 112. The gas flow passages 230 extend from the support surface 120 of the chuck body 214 to a bottom surface 232 of the cooling base 114. The gas flow passages 230 include a plurality of gas passages 234 formed in the electrostatic chuck 112, an opening 236 formed in the cooling base 114, and a cavity 240 formed in the chuck body 214 of the electrostatic chuck 112. The cavity 240 is defined by at least one sidewall 242 and a top wall 244 formed in the chuck body 214. The sidewall 242 has a diameter 246. The cavity 240 may have a cross-sectional area, e.g., a diameter, that is at least greater than the cross-sectional area of ​​the opening 236. Although the cavity 240 is illustrated as cylindrical, it may have other suitable shapes. Additionally, although a single gas passage 230 is shown in Figure 2, the substrate support pedestal 110 may include multiple gas passages.

[0061] The plurality of gas passages 234 extend from the support surface 120 through the chuck body 214 to the top wall 244 of the cavity 240 and are defined between the support surface 120 of the electrostatic chuck 112 and the top wall 244 of the cavity 240. In some implementations, the plurality of gas passages 234 are replaced with a single gas supply conduit that extends from the support surface 120 through the chuck body 214 to the top wall 244 of the cavity 240. Furthermore, the backside gas in the plurality of gas passages 234 provides a heat transfer medium between the electrostatic chuck 112 and the substrate 122. During operation, the backside gas is supplied by the gas source 124 to conduct into the plurality of gas passages 234 through the openings 236 through the porous plug 202. Furthermore, each gas flow passage 230 terminates in a corresponding plurality of gas passages 234 formed through the support surface 120 of the chuck body 214.

[0062] The porous plug 202 is generally disposed within the gas flow passage 230 (within the cavity 240) and thus forms a part of the gas flow passage 230. The porous plug 202 provides a path for pressurized gas to flow between two surfaces at different electrical potentials. The porous plug 202 can have an open-pore structure, meaning that the holes in the porous structure are interconnected so that fluid can flow through the porous plug 202. In some implementations, more than half of the cells in the open-pore structure are interconnected. For example, the porous plug 202 provides a path for pressurized gas to flow between the first and second surfaces of the electrostatic chuck 112 and between the first surface of the electrostatic chuck 112 and the first surface of the cooling base 114. Furthermore, the porous plug 202 comprises a plurality of small passages and / or holes that reduce the likelihood that a plasma will ignite in the gap 260 defined between the electrostatic chuck 112 and the cooling base 114, as compared to a design that does not include the porous plug 202. The porous plug 202 is generally composed of a ceramic material, such as aluminum oxide or aluminum nitride. Alternatively, the porous plug 202 may be composed of other porous materials. Additionally, the porous plug 202 may have a porosity of about 30 to about 80 percent. Alternatively, the porous plug may have a porosity of less than 30 percent or greater than 80 percent.

[0063] The porous plug 202 can be any suitable shape. In some implementations, the porous plug 202 has a cylindrical shape. Other suitable shapes include a T-shape, a tapered shape, and a rectangular shape. As shown in FIG. 2, the porous plug 202 includes a top surface 250, a sidewall 252, and a bottom surface 254. The sidewall 252 has a diameter 256. The diameter 256 of the sidewall 252 of the porous plug 202 is smaller than the diameter 246 defined by the at least one sidewall 242 of the cavity 240. The top surface 250 faces the top wall 244 of the cavity 240. The sidewall 252 of the porous plug 202 faces the at least one sidewall 242 of the cavity 240. The bottom surface 254 of the porous plug 202 faces the gap 260. The gap 260 is defined by the bottom surface 254 of the porous plug, the bonding layer 214, and the cooling base 114. The gap 260 is formed in the bonding layer 210 and is part of the gas flow passage 230. In some implementations, the bonding layer 210 further extends into the gap 260. For example, the bonding layer 210 can extend into the gap 260 and contact the sealing layer 204, or both the sealing layer 204 and the bottom surface 254 of the porous plug 202. In some implementations, the porous plug 202 can be positioned in the cavity 240 using various techniques such as press fit, slip fit, clearance fit, pinning, and bonding, among others. For example, the porous plug 202 can be positioned in the cavity 240 such that the top surface 250 of the porous plug 202 contacts the top wall 244 of the cavity 240.

[0064] The seal layer 204 is formed adjacent to the porous plug 202. The seal layer 204 forms a seal or radial seal between the sidewall 252 of the porous plug 202 and at least one sidewall 242 of the cavity 240. The seal layer 204 may form at least a radial seal between the porous plug 202 and the cavity 240. Furthermore, the seal layer 204 secures the porous plug 202 within the cavity 240. For example, the seal layer 204 may be coupled to at least one of the porous plug 202 and the at least one sidewall 242 of the cavity 240. The seal layer 204 may mechanically secure the porous plug 202 to the at least one sidewall 242 of the cavity 240.

[0065] As described herein, the sealing layer 204 may be comprised of a resilient polymeric material, such as an elastomer. Additionally, the sealing layer 204 may be comprised of one or more of a fluoroelastomer material, e.g., FKM, and a perfluoroelastomer material, e.g., FFKM. Additionally, the sealing layer 204 may be comprised of a material that is resistant to erosion by the process gas. For example, an erosion-resistant material does not erode in the presence of the process gas. Additionally or alternatively, the material of the sealing layer 204 is selected such that the material does not penetrate the porous plug 202. The sealing layer 204 may be an O-ring, a cylindrical gasket, or other ring-shaped seal. Additionally, the sealing layer 204 may be comprised of a substantially non-adhesive material. The sealing layer 204 is formed from a material that is applied in one of a liquid, a paste, and / or a gel and changes state to a substantially solid or gel form.

[0066] The sealing layer 204 typically has a thickness sufficient to seal the gap between the surface of the porous plug and the surface of the wall defining the cavity 240. In some implementations. The sealing layer 204 has a thickness of about 25 micrometers to about 2,000 micrometers. In some implementations, the sealing layer 204 has a minimum thickness of about 25 micrometers, about 50 micrometers, about 100 micrometers, about 150 micrometers, about 200 micrometers, about 250 micrometers, about 300 micrometers, about 400 micrometers, about 500 micrometers, about 600 micrometers, about 750 micrometers cP, about 1,000 micrometers, about 1,250 micrometers, about 1,500 micrometers, about 1,750 micrometers, about 1,850 micrometers, or about 1,950 micrometers. In some implementations, the sealing layer 204 has a maximum thickness of about 2,000 micrometers, about 1,950 micrometers, about 1,850 micrometers, about 1,750 micrometers, about 1,500 micrometers, about 1,250 micrometers, about 1,000 micrometers, about 750 micrometers, about 600 micrometers, about 500 micrometers, about 400 micrometers, about 300 micrometers, about 250 micrometers, about 200 micrometers, about 150 micrometers, about 100 micrometers, or about 50 micrometers.

[0067] The bonding layer 210 secures the chuck body 214 to the cooling base 114. The material or materials from which the bonding layer 210 is typically constructed are susceptible to erosion in the presence of process gases used during substrate processing, and therefore various methods have been considered to protect the bonding layer 210 from the process gases. Advantageously, by using a sealing layer, e.g., sealing layer 204, that is highly resistant to erosion by the process gases, the process gases may be prevented from passing through the porous plug 202, thereby increasing the life of the bonding layer 210. Additionally, the useful life of the substrate support pedestal 110 is increased.

[0068] 3 is a partial cross-sectional view of a portion 201 of a substrate support pedestal 110 having a bonded porous plug 300 according to one or more implementations of the present disclosure. The bonded porous plug 300 is similar to the bonded porous plug 202, except that at least one of the top surface 250 and the bottom surface 254 of the bonded porous plug 300 is partially coated with an additional sealing layer 302a, 302b (collectively 302). The additional sealing layer 302 provides additional protection against process gases and further reduces erosion of the bonding layer 210. The upper sealing layer 302a is formed between the upper wall 244 of the cavity 240 and the upper surface 250 of the porous plug 202. The upper sealing layer 302a forms an axial seal between the upper wall 244 of the cavity 240 and the upper surface 250 of the porous plug 202. A gap 304 is defined by the upper sealing layer 302a. The gap 304 is part of the gas flow path 230 and allows air to flow through the porous plug 202 to reach the multiple gas passages 234 and the backside of the substrate 122. The top sealing layer 302a may be in the shape of a gasket. The bottom sealing layer 302b is formed between the bottom surface 254 of the porous plug, the bonding layer 210, and the cooling base 114. The gap 260 is further defined by the bottom sealing layer 302b. The gap 260 allows air to reach and flow through the porous plug 202 to reach the multiple gas passages 234 and the backside of the substrate 122. The bottom sealing layer 302b may be in the shape of a gasket. In some implementations, the sealing layer 204, the top sealing layer 302a, and the bottom sealing layer 302b are separate layers. In other implementations, the sealing layer 204, the top sealing layer 302a, and the bottom sealing layer 302b form an integral layer.

[0069] FIG. 4 is a flow chart of one example of a method 400 for forming a substrate pedestal with a bonded porous plug according to one or more implementations of the present disclosure. The bonded porous plug includes a porous plug and a sealing layer. The sealing layer can be comprised of a fluoroelastomer (FKM), a perfluoroelastomer (FFKM), or a combination thereof. The sealing layer can be formed from a fluoroelastomer composition described herein. The method 400 can be used to produce the bonded porous plugs 200, 300 shown in FIG. 2 and FIG. 3, respectively. Although discussed with reference to FIG. 2 and FIG. 3, it should be understood that the method 400 can be used with other porous plug and substrate pedestal designs.

[0070] In operation 410, the porous plug is coated with a fluoroelastomer composition to form a first coating on the porous plug. The viscosity of the fluoroelastomer composition can be adjusted to easily apply the fluoroelastomer composition to the porous plug. With reference to FIG. 2 and FIG. 3, the fluoroelastomer composition can be applied to at least one of the top surface 250, bottom surface 254, and sidewall 252 of the porous plug 202. In one example, the fluoroelastomer composition is applied only to the sidewall 252. In another example, the fluoroelastomer composition is applied to the sidewall 252, bottom surface 254, and top surface 250 of the porous plug 202. In yet another example, the fluoroelastomer composition is applied to the sidewall 252 and either the bottom surface 254 or top surface 250 of the porous plug 202. The first coating can have a thickness of about 25 microns to about 1,000 microns, for example, about 50 microns to about 100 microns.

[0071] Optionally, the fluoroelastomer composition coated on the porous plug is partially or semi-cured in operation 420. Any suitable partial or semi-curing process can be used.

[0072] In operation 430, the cavity of the chuck body is coated with a fluoroelastomer composition to form a second coating. The viscosity of the fluoroelastomer composition can be adjusted to easily apply the fluoroelastomer composition to the cavity of the chuck body. With reference to Figures 2 and 3, the fluoroelastomer composition can be applied to at least one of the at least one sidewall 242 and the top wall 244 that define the cavity 240 formed in the chuck body 214 of the electrostatic chuck 112. The second coating can have a thickness of about 25 microns to about 1,000 microns, for example, about 50 microns to about 100 microns.

[0073] Optionally, the fluoroelastomer composition coated on the cavity walls defining the cavity is partially cured or semi-cured in operation 440. Any suitable partial or semi-curing process can be used.

[0074] In operation 450, the porous plug having the uncured or partially cured fluoroelastomer composition deposited thereon is inserted into the cavity having the uncured or partially cured fluoroelastomer composition deposited on the walls defining the cavity such that the fluoroelastomer composition coated on the walls defining the cavity contacts the fluoroelastomer composition coated on the porous plug. In some implementations, the porous plug 202 may be positioned within the cavity 240 using a variety of techniques such as press fit, sliding fit, clearance fit, pinning, and bonding, among others.

[0075] In operation 460, the fluoroelastomer composition formed between the porous plug and the wall defining the cavity is cured to form a sealing layer between the porous plug and the wall defining the cavity.

[0076] 5 is a flow chart of another example of a method 500 for forming a substrate pedestal with a bonded porous plug according to one or more implementations of the present disclosure. The bonded porous plug includes a porous plug and a sealing layer. The sealing layer can be comprised of a fluoroelastomer (FKM), a perfluoroelastomer (FFKM), or a combination thereof. The sealing layer can be formed from a fluoroelastomer composition described herein. The method 500 can be used to produce the bonded porous plugs 200, 300 shown in FIG. 2 and FIG. 3, respectively. Although discussed with reference to FIG. 2 and FIG. 3, it should be understood that the method 500 can be used with other porous plug and substrate pedestal designs.

[0077] In operation 510, the porous plug is coated with a fluoroelastomer composition. The viscosity of the fluoroelastomer composition can be adjusted to easily apply the fluoroelastomer composition to the porous plug. With reference to Figures 2 and 3, the fluoroelastomer composition can be applied to at least one of the top surface 250, bottom surface 254, and sidewall 252 of the porous plug 202. In one example, the fluoroelastomer composition is applied only to the sidewall 252. In another example, the fluoroelastomer composition is applied to the sidewall 252, bottom surface 254, and top surface 250 of the porous plug 202. In yet another example, the fluoroelastomer composition is applied to the sidewall 252 and either the bottom surface 254 or the top surface 250 of the porous plug 202.

[0078] Optionally, the fluoroelastomer composition coated on the porous plug is partially or semi-cured in operation 520. Any suitable partial or semi-curing process can be used.

[0079] In operation 530, the porous plug with the uncured or partially cured fluoroelastomer composition deposited thereon is inserted into the cavity such that the fluoroelastomer composition coated on the porous plug contacts the walls defining the cavity. In some implementations, the porous plug 202 may be positioned within the cavity 240 using a variety of techniques such as press fit, slip fit, clearance fit, pinning, and bonding, among others.

[0080] In operation 540, the fluoroelastomer composition formed between the porous plug and the wall defining the cavity is cured to form a sealing layer between the porous plug and the wall defining the cavity.

[0081] 6 is a flow chart of yet another example of a method 600 for forming a substrate pedestal with a bonded porous plug according to one or more implementations of the present disclosure. The bonded porous plug includes a porous plug and a sealing layer. The sealing layer can be comprised of a fluoroelastomer (FKM), a perfluoroelastomer (FFKM), or a combination thereof. The sealing layer can be formed from a fluoroelastomer composition described herein. The method 600 can be used to produce the bonded porous plugs 200, 300 shown in FIG. 2 and FIG. 3, respectively. Although discussed with reference to FIG. 2 and FIG. 3, it should be understood that the method 500 can be used with other porous plug and substrate pedestal designs.

[0082] In operation 610, the cavity walls of the chuck body are coated with a fluoroelastomer composition. The viscosity of the fluoroelastomer composition can be adjusted to easily apply the fluoroelastomer composition to the cavity of the chuck body. With reference to Figures 2 and 3, the fluoroelastomer composition can be applied to at least one of the at least one sidewall 242 and the top wall 244 that define the cavity 240 formed in the chuck body 214 of the electrostatic chuck 112.

[0083] Optionally, the fluoroelastomer composition coated on the cavity walls defining the cavity is partially cured or semi-cured in operation 620. Any suitable partial or semi-curing process can be used.

[0084] In operation 630, the porous plug is inserted into the cavity such that the porous plug contacts the fluoroelastomer composition formed on the walls defining the cavity. In some implementations, the porous plug 202 may be positioned within the cavity 240 using a variety of techniques such as press fit, slip fit, clearance fit, pinning, and bonding, among others.

[0085] In operation 640, the fluoroelastomer composition formed on the walls defining the cavity is cured to form a sealing layer between the porous plug and the walls defining the cavity.

[0086] FIG. 7 is a flow chart of yet another example of a method 700 for forming a substrate pedestal with a bonded porous plug according to one or more implementations of the present disclosure. The bonded porous plug includes a porous plug and a sealing layer. The sealing layer can be comprised of a fluoroelastomer (FKM), a perfluoroelastomer (FFKM), or a combination thereof. The sealing layer can be formed from a fluoroelastomer composition described herein. The method 700 can be used to produce the bonded porous plugs 200, 300 shown in FIG. 2 and FIG. 3, respectively. Although discussed with reference to FIG. 2 and FIG. 3, it should be understood that the method 700 can be used with other porous plug and substrate pedestal designs.

[0087] In operation 710, the porous plug is coated with a fluoroelastomer composition. The viscosity of the fluoroelastomer composition can be adjusted to easily apply the fluoroelastomer composition to the porous plug. With reference to Figures 2 and 3, the fluoroelastomer composition can be applied to at least one of the top surface 250, bottom surface 254, and sidewall 252 of the porous plug 202. In one example, the fluoroelastomer composition is applied only to the sidewall 252. In another example, the fluoroelastomer composition is applied to the sidewall 252, bottom surface 254, and top surface 250 of the porous plug 202. In yet another example, the fluoroelastomer composition is applied to the sidewall 252 and either the bottom surface 254 or the top surface 250 of the porous plug 202.

[0088] In operation 720, the fluoroelastomer composition formed on the porous plug is cured to form a sealing layer on the porous plug. In some examples where the sealing layer 204 is formed on the sidewall 252 and at least one of the bottom sealing layer 302b is formed on the bottom surface 254 and the top sealing layer 302a is formed on the top surface 250 of the porous plug 202, portions of the top sealing layer 302a may be removed to form the gap 304 and portions of the bottom sealing layer 302b may be removed to form the gap 260, thereby allowing gas to flow through the porous plug. The portions of the top sealing layer 302a and the bottom sealing layer 302b may be removed before the semi-curing and / or curing of the fluoroelastomer composition forming the sealing layer, or after the semi-curing or curing.

[0089] In operation 730, the porous plug with the sealing layer formed thereon is inserted into the cavity such that the sealing layer contacts the walls defining the cavity. In some implementations, the porous plug 202 with the sealing layer may be positioned within the cavity 240 using a variety of techniques such as press fit, sliding fit, clearance fit, pinning, and bonding, among others.

[0090] FIG. 8 is a flow chart of yet another example of a method 800 for forming a substrate pedestal with bonded porous plugs according to one or more implementations of the present disclosure. FIGS. 9A-9C show schematic cross-sectional views of forming a substrate pedestal with bonded porous plugs according to one or more implementations of the present disclosure. The bonded porous plugs include a porous plug and a sealing layer. The sealing layer can be comprised of a fluoroelastomer (FKM), a perfluoroelastomer (FFKM), or a combination thereof. The sealing layer can be formed from a fluoroelastomer composition described herein. The method 800 can be used to produce the bonded porous plugs 200, 300 shown in FIGS. 2 and 3, respectively. Although discussed with reference to FIGS. 2, 3, and 9A-9C, it should be understood that the method 800 can be used with other porous plug and substrate pedestal designs.

[0091] In operation 810, the walls of the cavity of the chuck body 214 are coated with a fluoroelastomer composition 904, such as a fluoroelastomer composition described herein. The viscosity of the fluoroelastomer composition 904 can be adjusted to easily apply the fluoroelastomer composition to the walls of the cavity 240 of the chuck body 214. With reference to FIG. 9, the fluoroelastomer composition 904 can be applied to at least one of the at least one sidewall 242 and the top wall 244 that define the cavity 240 formed in the chuck body 214 of the electrostatic chuck 112, as shown in FIG. 9A.

[0092] Optionally, in operation 820, the fluoroelastomer composition 904 coated on the walls defining the cavity 240 can be partially cured or fully cured. Any suitable partial curing or curing process can be used.

[0093] Optionally, in operation 830, the porous plug can be coated with a fluoroelastomer composition 904 as previously described herein.

[0094] Optionally, in operation 840, the fluoroelastomer composition 904 coated on the porous plug 202 can be partially cured or fully cured. Any suitable partial curing or curing process can be used.

[0095] In operation 850, the porous plug 202 is inserted into the cavity 240 such that the porous plug 202 contacts the fluoroelastomer composition 904 formed on the walls defining the cavity 240. FIG. 9C shows an enlarged partial cross-sectional view of a portion of FIG. 9B. As shown in FIG. 9C, the viscosity of the fluoroelastomer composition 904 is adjusted such that the fluoroelastomer composition 904 fills or partially fills the surface pores 910 located along the outer surface or sidewalls of the porous plug 202 without substantially filling the interior pores 920 of the porous plug 202. The fluoroelastomer composition 904 bonds the porous plug 202 to the walls of the cavity 240 or holds the porous plug 202 in place due to the elastic properties of the bonding material exerting a compressive force on various surfaces of the porous plug 202 and / or the sidewalls of the cavity 240.

[0096] In operation 860, the fluoroelastomer composition 904 formed on the walls defining the cavity is cured to form a sealing layer between the porous plug 202 and the walls defining the cavity 240, such as the sealing layer 204 as shown in Figures 2 and 3.

[0097] The seal members and porous plugs described herein are suitable for use in a substrate support pedestal to protect a bonding layer that bonds a cooling base with an electrostatic chuck from process gases. Advantageously, protecting the bonding layer from process gases reduces erosion of the bonding layer and maintains a substantially uniform temperature on the substrate. For example, a seal member that is erosion-resistant to process gases may be utilized to form a radial seal and / or a vertical seal between the porous plugs of the electrostatic chuck. Such a seal member prevents inflow of process gas into the gap between the electrostatic chuck and the cooling base and reduces erosion of the bonding layer. Thus, substantially uniform heat transfer between the cooling base and the electrostatic chuck and a uniform temperature on the substrate is maintained.

[0098] All of the implementations and functional operations described herein can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structural means disclosed herein and their structural equivalents, or in combinations thereof. The implementations described herein can be implemented as one or more non-transitory computer program products, i.e., one or more computer programs tangibly embodied in a data processing apparatus, e.g., a programmable processor, a computer, or a plurality of processors or computers, for execution by or for controlling the operation of a data processing apparatus.

[0099] The processes and logic flows described herein can be performed by one or more programmable processors executing one or more computer programs that perform functions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, for example, an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit).

[0100] The term "data processing apparatus" encompasses all apparatus, devices, and machines that process data, including, by way of example, a programmable processor, a computer, or multiple processors or computers. In addition to hardware, the apparatus may include code that provides an execution environment for the subject computer program, such as code that constitutes a processor firmware, a protocol stack, a database management system, an operating system, or one or more combinations of these. Processors suitable for the execution of computer programs include, by way of example, both general-purpose and special-purpose microprocessors, as well as any one or more processors of any kind of digital computer.

[0101] Computer-readable media suitable for storing computer program instructions and data include all types of non-volatile memory, media, and memory devices, including, by way of example, semiconductor memory devices such as, for example, EPROM, EEPROM, and flash memory devices, magnetic disks such as an internal hard disk or a removable disk, magneto-optical disks, and CD-ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

[0102] Embodiments of the present disclosure further relate to any one or more of the following Examples 1-20.

[0103] 1. A method of fabricating a chuck body, comprising: coating a porous plug with a coating comprising a fluoroelastomer composition; inserting the coated porous plug into a cavity formed in the chuck body; and curing the coating to form a sealing layer between the porous plug and a wall of the cavity.

[0104] 2. The method according to example 1, wherein the coating has a thickness of about 25 microns to about 1,000 microns.

[0105] 3. The method according to example 1 or 2, further comprising partially curing the coating to form a partially cured fluoroelastomer layer on the porous plug prior to inserting the porous plug.

[0106] 4. The method according to any one of Examples 1-3, wherein the sealing layer forms a radial seal between the porous plug and the wall of the cavity.

[0107] 5. The method according to any one of Examples 1-4, wherein the sealing layer further forms at least one of a first axial seal between the porous plug and a cooling base coupled to the chuck body, and a second axial seal between an upper surface of the porous plug and a second wall of the cavity.

[0108] 6. The method according to any one of Examples 1 to 5, wherein the fluoroelastomer composition is a paste having a viscosity of about 50 cP to about 5,000 cP.

[0109] 7. The method according to any one of Examples 1-6, wherein the fluoroelastomer composition comprises at least one perfluoropolymer.

[0110] 8. The method according to any one of Examples 1-7, wherein the fluoroelastomer composition further comprises at least one of a curing agent, an adhesion promoter, a thickener, a solvent, and a filler.

[0111] 9. A method of fabricating a chuck body, comprising: coating a wall of a cavity formed in the chuck body with a coating comprising a fluoroelastomer composition, inserting a porous plug into the cavity, and curing the coating to form a sealing layer between the porous plug and the wall of the cavity.

[0112] 10. The method according to example 9, further comprising partially curing the coating to form a partially cured fluoroelastomer layer on the wall of the cavity prior to inserting the porous plug.

[0113] 11. The method according to example 9 or 10, wherein the sealing layer forms a radial seal between the porous plug and the wall of the cavity.

[0114] 12. The method according to any one of examples 9-11, wherein the sealing layer further forms at least one of a first axial seal between the porous plug and a cooling base coupled to the chuck body, and a second axial seal between an upper surface of the porous plug and a second wall of the cavity.

[0115] 13. The method according to any one of Examples 9-12, wherein the fluoroelastomer composition is a paste having a viscosity of about 50 cP to about 5,000 cP.

[0116] 14. The method according to any one of Examples 9-13, wherein the fluoroelastomer composition comprises at least one perfluoropolymer.

[0117] 15. The method according to any one of Examples 9-14, wherein the fluoroelastomer composition further comprises at least one of a curing agent, an adhesion promoter, a thickener, a solvent, and a filler.

[0118] 16. A method of fabricating a chuck body, comprising: coating a porous plug with a first coating comprising a fluoroelastomer composition; coating a wall of a cavity formed in the chuck body with a second coating comprising a fluoroelastomer composition; inserting the porous plug having the first coating formed thereon into the cavity having the second coating formed thereon; and curing the first coating and the second coating to form a sealing layer between the porous plug and the wall of the cavity.

[0119] 17. The method according to example 16, further comprising partially curing at least one of the first coating and the second coating to form a partially cured fluoroelastomer layer on at least one of the porous plug and the wall of the cavity prior to inserting the porous plug.

[0120] 18. The method according to example 16 or 17, wherein the sealing layer forms a radial seal between the porous plug and the wall of the cavity.

[0121] 19. The method according to any one of examples 16-18, wherein the sealing layer further forms at least one of a first axial seal between the porous plug and a cooling base coupled to the chuck body, and a second axial seal between an upper surface of the porous plug and a second wall of the cavity.

[0122] 20. The method according to any one of Examples 16-19, wherein the fluoroelastomer composition is in a paste form having a viscosity of about 50 cP to about 5,000 cP and comprises at least one perfluoropolymer, and optionally at least one of a curing agent, an adhesion promoter, a thickener, a solvent, and a filler.

[0123] The foregoing is directed to embodiments of the present disclosure, although other and further embodiments may be devised without departing from the basic scope of the invention, the scope of which is determined by the following claims. All documents cited herein, including any priority documents and / or test procedures, are incorporated herein by reference to the extent not inconsistent with the body of this specification. As is apparent from the general description and specific embodiments set forth above, forms of the disclosure have been illustrated and described, but various modifications may be made without departing from the spirit and scope of the disclosure. It is therefore not intended that the disclosure be limited thereby. Similarly, for purposes of U.S. law, the term "comprising" is considered synonymous with the term "including." Similarly, it is to be understood that whenever a composition, element, or group of elements is preceded by the transitional phrase "comprising," the transitional phrase "consisting essentially of," "consisting of," "selected from the group consisting of," or "is" is considered to be the same composition or group of elements preceded by the transitional phrase "consisting essentially of," "consisting of," "selected from the group consisting of," or "is" before the recitation of the composition, element, or multiple elements, and vice versa. As used herein, the term "about" refers to a + / - 10% variation from the nominal value. It is understood that such a variation can be included in any value provided herein.

[0124] Certain embodiments and features are described using a series of numerical minimums and a series of numerical maximums. It should be understood that unless otherwise indicated, ranges including combinations of any two values ​​are contemplated, such as combinations of any minimum value with any maximum value, combinations of any two minimum values, and / or combinations of any two maximum values. Certain minimum values, maximum values, and ranges are set forth in one or more of the following claims.

Claims

1. 1. A method of making a chuck body, comprising the steps of: coating the porous plug with a coating comprising an elastomeric composition; inserting the porous plug having the coating thereon into a cavity formed in the chuck body; and curing the coating to form a sealing layer between the porous plug and a wall of the cavity. The elastomeric composition comprises a thickener comprising cellulose. method.

2. The method of claim 1 , wherein the coating has a thickness of about 25 microns to about 1,000 microns.

3. The method of claim 1 , further comprising partially curing the coating to form a partially cured fluoroelastomer layer on the porous plug prior to inserting the porous plug.

4. The method of claim 1 , wherein the sealing layer forms a radial seal between the porous plug and the wall of the cavity.

5. 5. The method of claim 4, wherein the sealing layer further forms at least one of a first axial seal between the porous plug and a cooling base coupled to the chuck body, and a second axial seal between a top surface of the porous plug and a second wall of the cavity.

6. The method of claim 1 , wherein the elastomeric composition is in the form of a paste having a viscosity of about 50 cP to about 5,000 cP.

7. 7. The method of claim 6, wherein the elastomeric composition comprises at least one perfluoropolymer and the cellulose comprises a metal salt of a carboxyalkylcellulose derivative, or an alkylcellulose derivative, or an oxidized alkylcellulose derivative, or a combination thereof.

8. The method of claim 7 , wherein the elastomeric composition further comprises at least one of a curing agent, an adhesion promoter, a solvent, and a filler.

9. 1. A method of making a chuck body, comprising the steps of: coating a wall of a cavity formed in the chuck body with a coating comprising an elastomeric composition; inserting a porous plug into the cavity having the coating; and curing the coating to form a sealing layer between the porous plug and the wall of the cavity. The elastomeric composition is in the form of a paste having a viscosity of about 50 cP to about 5,000 cP and includes a thickening agent comprising cellulose. method.

10. 10. The method of claim 9, further comprising partially curing the coating to form a partially cured fluoroelastomer layer on the walls of the cavity prior to inserting the porous plug.

11. The method of claim 9 , wherein the sealing layer forms a radial seal between the porous plug and the wall of the cavity.

12. 10. The method of claim 9, wherein the sealing layer further forms at least one of a first axial seal between the porous plug and a cooling base coupled to the chuck body and a second axial seal between a top surface of the porous plug and a second wall of the cavity.

13. The method of claim 9, wherein the elastomeric composition is in the form of a paste having a viscosity of about 100 cP to about 3,000 cP.

14. 14. The method of claim 13, wherein the elastomeric composition comprises at least one perfluoropolymer and the cellulose comprises a metal salt of a carboxyalkylcellulose derivative, or an alkylcellulose derivative, or an oxidized alkylcellulose derivative, or a combination thereof.

15. The method of claim 14 , wherein the elastomeric composition further comprises at least one of a curing agent, an adhesion promoter, a solvent, and a filler.

16. 1. A method of making a chuck body, comprising the steps of: coating the porous plug with a first coating comprising an elastomeric composition; coating a wall of a cavity formed in a chuck body with a second coating comprising the elastomeric composition; inserting the porous plug having the first coating thereon into the cavity having the second coating thereon; and curing the first coating and the second coating to form a sealing layer between the porous plug and the wall of the cavity; The elastomeric composition comprises a thickener comprising cellulose. method.

17. 17. The method of claim 16, further comprising partially curing at least one of the first coating and the second coating to form a partially cured fluoroelastomer layer on at least one of the porous plug and the wall of the cavity prior to inserting the porous plug.

18. The method of claim 16 , wherein the sealing layer forms a radial seal between the porous plug and the wall of the cavity.

19. 20. The method of claim 18, wherein the sealing layer further forms at least one of a first axial seal between the porous plug and a cooling base coupled to the chuck body and a second axial seal between a top surface of the porous plug and a second wall of the cavity.

20. 20. The method of claim 18, wherein the elastomeric composition is a paste having a viscosity of about 50 cP to about 5,000 cP and comprises at least one perfluoropolymer and, optionally, at least one of a curing agent, an adhesion promoter, a solvent, and a filler.

21. The method of any one of claims 1, 9, or 16, wherein the cellulose comprises sodium carboxymethylcellulose, methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, or a combination thereof.

22. The method of any one of claims 1, 9, or 16, wherein the elastomer composition comprises a fluoroelastomer composition.

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