Plasma-resistant structure, production method for plasma-resistant structure, electrostatic chuck, edge ring, fiber structure, plasma processing device member, and repair method for plasma processing device member

Abstract

[Problem] To provide a plasma-resistant structure, an electrostatic chuck, an edge ring, a fiber structure, and a plasma processing device member that have a long life, a production method for the plasma-resistant structure, and a repair method for the plasma processing device member. [Solution] A plasma-resistant structure 1 comprises a first member 2, a second member 3, an intermediate member 4 that is provided between the first member 2 and the second member 3, and a plasma protection material 5 that includes fibers. At least one of the first member 2 and the second member 3 is plasma-resistant, and the plasma protection material 5 that includes fibers is provided on the outer surface side at the ends of the intermediate member 4.

Description

Plasma-resistant structure, method for manufacturing plasma-resistant structure, electrostatic chuck, edge ring, fiber structure, member for plasma processing apparatus, and method for repairing member for plasma processing apparatus

[0001] The present invention relates to a plasma-resistant structure, a method for manufacturing a plasma-resistant structure, an electrostatic chuck, an edge ring, a fiber structure, a member for a plasma processing apparatus, and a method for repairing a member for a plasma processing apparatus.

[0002] Conventionally, etching apparatuses that dry-etch an object using plasma have been used as semiconductor manufacturing equipment, and the etching apparatuses use electrostatic chucks to fix the object using static electricity. In the electrostatic chuck, a holding member that fixes and holds the object and a base that holds the holding member are bonded by a bonding layer, and a plasma protection layer that reduces damage to the bonding layer by plasma is bonded to the outer surface of the bonding layer (Patent Documents 1 and 2).

[0003] JP 2010-165776 A JP 2021-44303 A

[0004] The plasma protective layers described in Patent Documents 1 and 2 are formed from a thermosetting resin or an elastomer, and further improvement is required in terms of plasma resistance, etc. Similarly, in order to maintain hermeticity in a sealed space using plasma in a plasma processing apparatus, etc., further improvement is required in terms of plasma resistance, etc. Such improvement is expected to extend the life of electrostatic chucks, plasma processing apparatuses, etc.

[0005] An object of the present invention is to provide a long-life plasma-resistant structure, an electrostatic chuck, an edge ring, a fiber structure, a member for a plasma processing apparatus, a method for manufacturing such a plasma-resistant structure, and a method for repairing a member for a plasma processing apparatus.

[0006] The plasma-resistant structure of the present disclosure is a plasma-resistant structure comprising a first member, a second member, an intermediate member disposed between the first member and the second member, and a plasma protective material containing fibers, wherein at least one of the first member and the second member has plasma resistance, and the plasma protective material containing fibers is disposed on the outer surface side of the plasma-resistant structure at an end of the intermediate member.

[0007] In the plasma-resistant structure of the present disclosure, the plasma protective material containing the fiber may be disposed on the outer periphery of the intermediate member.

[0008] In the plasma-resistant structure of the present disclosure, the fibers may extend along an outer periphery of the intermediate member.

[0009] In the plasma-resistant structure of the present disclosure, the plasma protective material containing fibers may include a fiber structure made of fibers.

[0010] In the plasma-resistant structure of the present disclosure, the fiber structure may extend along an outer periphery of the intermediate member.

[0011] In the plasma-resistant structure of the present disclosure, the intermediate member may be a bonding layer.

[0012] In the plasma-resistant structure of the present disclosure, the length of the fibers in the extending direction may be longer than the outer periphery of the intermediate member, and the fibers may be wound around the outer periphery of the intermediate member.

[0013] In the plasma-resistant structure of the present disclosure, the length of the fiber structure in the extending direction may be longer than the outer periphery of the intermediate member, and the fiber structure may be wound around the outer periphery of the intermediate member.

[0014] In the plasma-resistant structure of the present disclosure, the fibers may be inorganic fibers.

[0015] In the plasma-resistant structure of the present disclosure, the fiber structure may include at least one of twisted yarn, nonwoven fabric, mesh, or woven fabric.

[0016] The electrostatic chuck of the present disclosure includes the plasma-resistant structure of the present disclosure, wherein the first member is a holding member that holds an object to be held, and the second member is a base that holds the holding member.

[0017] In the electrostatic chuck of the present disclosure, the outermost periphery of the holding member may be located outside the outermost point of the plasma protection material.

[0018] In the electrostatic chuck of the present disclosure, the outermost periphery of the base may be located outside the outermost point of the plasma protection material.

[0019] The edge ring of the present disclosure is characterized by having the plasma-resistant structure of the present disclosure.

[0020] The member for a plasma processing apparatus according to the present disclosure is characterized by having the plasma-resistant structure according to the present disclosure.

[0021] The fiber structure of the present disclosure is a fiber structure having fibers, characterized in that in a plasma-resistant structure comprising a first member, a second member, an intermediate member arranged between the first member and the second member, and the fiber structure of the present disclosure, the intermediate member is arranged along the outer periphery of the intermediate member.

[0022] The method for manufacturing a plasma-resistant structure according to the present disclosure includes a first member, a second member, an intermediate member disposed between the first member and the second member, and a fiber structure having fibers, and is characterized by including the steps of: disposing the intermediate member between the first member and the second member; and winding the fiber structure around an outer periphery of the intermediate member.

[0023] The method for repairing a member for a plasma processing apparatus according to the present disclosure is a method for repairing a member for a plasma processing apparatus comprising a first member, a second member, and an intermediate member disposed between the first member and the second member, and is characterized by including a step of winding a fiber structure having fibers around an outer periphery of the intermediate member.

[0024] According to the present disclosure, there are provided a long-life plasma-resistant structure, an electrostatic chuck, an edge ring, a fiber structure, a member for a plasma processing apparatus, a method for manufacturing such a plasma-resistant structure, and a method for repairing a member for a plasma processing apparatus.

[0025] FIG. 1 is a cross-sectional view showing a schematic configuration of a plasma-resistant structure according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view showing another schematic configuration of a plasma-resistant structure according to an embodiment of the present disclosure. FIG. 3 is a diagram showing an outline of a method for repairing a plasma-resistant structure (electrostatic chuck) according to an embodiment of the present disclosure. FIG. 4 is a cross-sectional view showing a schematic configuration of an electrostatic chuck according to an embodiment of the present disclosure. FIG. 5 is a cross-sectional view showing another schematic configuration of an electrostatic chuck according to an embodiment of the present disclosure. FIG. 6 is a diagram showing a schematic configuration of an edge ring according to an embodiment of the present disclosure. FIG. 7 is a schematic configuration diagram in which an edge ring is arranged to surround an electrostatic chuck according to an embodiment of the present disclosure. FIG. 8 is a cross-sectional view of a fiber bundle as an example of a fiber structure according to an embodiment of the present disclosure. FIG. 9 is a cross-sectional photograph of a plasma-resistant structure according to an embodiment of the present disclosure. FIG. 10 is a cross-sectional photograph of a plasma-resistant structure according to another embodiment of the present disclosure. FIG. 11 is a cross-sectional photograph of a plasma-resistant structure according to another embodiment of the present disclosure. FIG. 12 is a cross-sectional view showing another schematic configuration of an electrostatic chuck according to an embodiment of the present disclosure.

[0026] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings, but the invention according to the present disclosure is not limited thereto.

[0027] [Plasma-Resistant Structure] FIGS. 1 and 2 are cross-sectional views showing a schematic configuration of a plasma-resistant structure according to an embodiment of the present disclosure. As shown in FIG. 1 , the plasma-resistant structure 1 includes a first member 2, a second member 3, an intermediate member 4 disposed between the first member 2 and the second member 3, and a plasma protective material 5 containing fibers. At least one of the first member 2 and the second member 3 has plasma resistance. The plasma protective material 5 containing fibers (hereinafter simply referred to as the plasma protective material 5) is disposed on the outer surface side of the plasma-resistant structure 1 at the end of the intermediate member 4. Here, the "outer surface side" of the plasma-resistant structure 1 refers to the side that contacts the external atmosphere. In FIG. 6(B), which is a cross-sectional view showing a schematic configuration of an edge ring according to an embodiment of the present disclosure, plasma protective materials 45a and 45b (plasma protective materials 5) are disposed on the outer and inner peripheries of the edge ring 41 (plasma-resistant structure 1) at the end of the intermediate member 44, and both of these outer and inner peripheries are located on the outer surface side of the plasma-resistant structure 1 (edge ​​ring 41) that contacts the external atmosphere.

[0028] The plasma-resistant structure 1 can be used in a plasma atmosphere during the semiconductor manufacturing process (examples of applications include semiconductor manufacturing equipment, plasma processing equipment, parts installed and used inside the equipment, electrostatic chucks, edge rings, upper electrodes, inner walls of the equipment, ventilation valves, sealing members, etc.). Use in these applications improves the durability of the semiconductor manufacturing equipment, etc., and makes the semiconductor manufacturing process more efficient.

[0029] (First member 2 and second member 3) In the plasma-resistant structure 1, it is sufficient that either the first member 2 or the second member 3 has plasma resistance. That is, only the first member 2 may be formed from a material that is plasma-resistant (plasma-resistant material), or only the second member 3 may be formed from a plasma-resistant material. It is preferable that both the first member 2 and the second member 3 are formed from a plasma-resistant material, because this can more effectively protect the intermediate member 4 disposed therebetween from plasma.

[0030] Furthermore, it is preferable that the first member 2 and the second member 3 have a planar, disc-like, plate-like, cubic, columnar, or other shape, since this allows them to efficiently cover the intermediate member 4 and more effectively protect the intermediate member 4 from plasma. These may also be removed in any desired pattern (e.g., ring-like, arc-like, comb-like, or other). The first member 2 and / or the second member 3 may be a plasma protective material 5 containing fibers, as described below. Like the first member 2a of the plasma-resistant structure 1a shown in FIG. 2 , the first member 2 and / or the second member 3 may be a plasma protective material 5 containing fibers. The first member 2 and / or the second member 3 may be composed of multiple components.

[0031] Examples of plasma-resistant materials include organic and inorganic materials. Preferred organic materials include, but are not limited to, nylon, polyimide, polyamide, polyester, acrylic, polyolefin, aromatic polyether ketone, polyphenylene sulfide, fluororesin, polyvinyl alcohol, ethylene-vinyl alcohol resin, phenolic resin, vinyl chloride, and silicone resin. Preferred inorganic materials include, but are not limited to, metals and ceramics. Examples of inorganic materials include materials containing at least one of yttrium, aluminum, zirconium, hafnium, calcium, magnesium, nickel, titanium, and silicon, and may be oxides, hydroxides, carbides, or mixtures (minerals, etc.) of these elements, and the mixture may contain hydroxyapatite.

[0032] (Intermediate Member 4) The intermediate member 4 is not particularly limited and may have functions such as bonding (including re-peelable temporary bonding), sealing, insulation, heat control (thermal insulation, heat conduction), and conductivity (hereinafter also referred to as "functional member"), or it may be a filler or space with no intended function. Therefore, the material of the intermediate member 4 is also not limited. The shape of the intermediate member 4 is also not particularly limited and may be hollow, layered, plate-like, tabular, columnar, etc., or may be a laminate of these, a structure in which these are removed in any pattern (e.g., ring-shaped, arc-shaped, comb-shaped, etc.), or a combination of multiple these. However, layered, plate-shaped, plate-shaped, columnar, etc. are preferred because they reduce the area of ​​the intermediate member 4 that comes into contact with the plasma atmosphere (external atmosphere). Furthermore, the intermediate member 4 may or may not be plasma-resistant. It is preferable that most of the intermediate member 4 be covered by the first member 2 and the second member 3. Specifically, the area of ​​the intermediate member 4 that comes into contact with the first member 2 and the second member 3 is preferably at least 10 times the area of ​​the intermediate member 4 facing the plasma protective material 5. As a result, most of the outer surface of the plasma-resistant structure 1 is plasma-resistant, ensuring plasma resistance of the plasma-resistant structure 1. Specific examples of the intermediate member 4 include a sealing material (O-ring), a bonding layer (bonding layer 14 in FIG. 4 ), a heat insulating layer, a heat transfer layer, and the like.

[0033] In addition, when the intermediate member 4 has an inner circumferential side (such as a ring-shape, for example, when the plasma-resistant structure 1 is an edge ring, an electrostatic chuck 31 having a penetration portion, etc.) and the inner circumferential side of the intermediate member 4 is in contact with the plasma space, it is preferable to arrange the plasma protective material 5 on the inner circumferential side of this ring, and it is more preferable to arrange the plasma protective material 5 along the inner circumferential side of this ring.

[0034] (Bonding Layer) The bonding layer, which is one of the functional members, is not particularly limited, and metals, adhesive materials (resins), etc. can be used. As the metal, brazing materials (silver brazing, copper brazing, copper alloy brazing, aluminum brazing, nickel brazing, activated silver brazing, titanium brazing, solder materials, etc.) can be used from the viewpoint of workability. Among these, a more appropriate one can be selected in relation to the properties (thermal expansion, thermal conductivity, etc.) of the first member 2 and the second member 3 to be joined.

[0035] The bonding layer may have not only a bonding function but also other functions, such as electrical insulation, heat insulation, heat conduction, and electrical conductivity.

[0036] (Adhesive Material) The bonding layer (functional member) may be an adhesive material. Examples of adhesive materials include silicone resin, fluororesin, epoxy resin, acrylic resin, polyimide resin, polyamide resin, polyester resin, polyolefin resin, and adhesive materials containing fillers. From the viewpoint of adhesion and heat resistance, silicone resin, fluororesin, acrylic resin, polyimide resin, and adhesive materials containing fillers are preferred. Silicone resin, acrylic resin, epoxy resin, and adhesive materials containing fillers are more preferred. Silicone resin and silicone resin containing fillers are even more preferred, but are not limited to these. Silicone resin has excellent stress relaxation properties and can provide a plasma-resistant structure 1 that is less susceptible to damage due to temperature changes. Furthermore, silicone resin mixed with a thermally conductive filler improves the heat exchange capacity between the first member 2 and the second member 3 and can reduce damage due to partial overheating of the plasma-resistant structure 1. As a result, a plasma-resistant structure 1 with a long life can be provided.

[0037] (Sealing Material) The intermediate member 4 may be a sealing material. Examples of sealing materials include silicone, polyimide, aromatic polyether ketone, fluororesin, epoxy resin, urethane resin, acrylic resin, elastomer, and a mixture of these sealing materials with a filler. From the viewpoint of plasma resistance and heat resistance, polyimide, fluororesin, epoxy resin, and a mixture of fluororesin and a thermally conductive filler are preferred, but are not limited to these. The sealing material may be ring-shaped (e.g., an O-ring), or may be formed by pouring an uncured curable liquid resin into any shape. A mixture of fluororesin and a filler has excellent durability (plasma resistance and damage prevention), thereby providing a plasma-resistant structure 1 with a long life. In this case, examples of fillers include ceramic particles from the viewpoint of plasma resistance. Specifically, oxides, hydroxides, and carbides containing at least one of yttrium, aluminum, zirconium, hafnium, calcium, magnesium, nickel, titanium, and silicon are included. From the viewpoint of plasma resistance and insulating properties, examples of suitable materials include yttrium oxide, aluminum oxide, and aluminum nitride. This allows for the provision of a sealing material with excellent plasma resistance and insulating properties. As a result, a plasma-resistant structure 1 with a long life can be provided.

[0038] The sealing material may have not only a sealing function but also other functions, such as electrical insulation, heat insulation, heat conduction, and electrical conductivity.

[0039] (Thermal Insulation Material) The intermediate member 4 may be a thermal insulator. Examples of the thermal insulator include, but are not limited to, resin materials, metal materials, etc. Examples of the resin materials include silicone, polyimide, aromatic polyether ketone, fluororesin, epoxy resin, urethane resin, acrylic resin, elastomer, etc. Examples of the metal materials include, but are not limited to, stainless steel, etc. Examples of the thermal insulators include, but are not limited to, those with voids (e.g., foam, etc.). This allows for strict thermal management of the plasma-resistant structure 1 and suppresses damage due to overheating. As a result, a plasma-resistant structure 1 with a long life can be provided. Note that the thermal insulator may have other functions in addition to the thermal insulation function. Examples of the thermal insulator include bonding, insulation, and conductivity.

[0040] (Plasma Protection Material 5) The plasma protection material 5 includes fibers and is formed from a plasma-resistant material. The plasma protection material 5 protects the intermediate member 4, such as a resin material, from the plasma space, isolating or distancing the resin material from the plasma space. The plasma protection material 5 blocks the path from the plasma space to the intermediate member 4, increasing the distance the plasma must travel to reach the intermediate member 4. This deactivates the plasma and reduces its impact on the intermediate member 4. When the plasma protection material 5 is made of fibers, voids are formed between and around the fibers. These voids allow the material to adapt to dimensional changes in the external environment and relieve stress (cushioning properties). For example, the plasma protection material 5 can adapt to dimensional changes in the first member 2 and the second member 3 due to heating and relieve stress caused by the dimensional changes, thereby extending the life of the plasma-resistant structure 1. Furthermore, when the plasma protection material 5 is made of ceramics or the like and mixed with fibers, the fibers act as aggregates for the ceramics, increasing the stress resistance of the plasma protection material 5. As a result, the stress resistance against external dimensional changes is increased, and the life of the plasma-resistant structure 1 is extended.

[0041] The fibers constituting the plasma protective material 5 are preferably inorganic fibers, examples of which include those containing at least one of yttrium, aluminum, zirconium, hafnium, calcium, magnesium, nickel, titanium, and silicon. The plasma protective material 5 may also be made of, but is not limited to, oxides, hydroxides, carbides of these, fibers in which the surface of organic fibers is coated with these inorganic compounds, or mixtures thereof. Further, commercially available inorganic fibers include Fineflex manufactured by Nichias Corporation, Isowool manufactured by Isolite Industries Co., Ltd., Ibiwool manufactured by Ibiden Co., Ltd., Superwool manufactured by Shin-Nichika Thermal Ceramics Co., Ltd., Nextel manufactured by 3M Corporation, N-Silica manufactured by Nippon Glass Fiber Industries Co., Ltd., BelCo Tex manufactured by BelChem, Nichibi Alf manufactured by Nichibi Co., Ltd., Almax and Saffi manufactured by Mitsui Mining Materials Co., Ltd. Examples of such fibers include SAFFIL manufactured by Fibres, Denka Arsen manufactured by Denka Company, LUBIL manufactured by Nichias Corporation, MAFTEC manufactured by Mitsubishi Chemical Industrial Products, Altex manufactured by Sumitomo Chemical Co., Ltd., Rockfiber manufactured by Nitto Boseki Co., Ltd., MG Mightywool manufactured by Nichias Corporation, S-fiber manufactured by Nippon Rockwool Industries Co., Ltd., Rockfil manufactured by Lapinas, Nicalon manufactured by Nippon Carbon Co., Ltd., Tyranno Fiber manufactured by Ube Industries, Ltd., Naslon manufactured by Nippon Seisen Co., Ltd., Bekipor manufactured by Bekaert, BOLFUR manufactured by Unitika Ltd., SENCY manufactured by Unitika Ltd., Unitika Glass Fiber manufactured by Unitika Ltd., Nittobo Glass Fiber manufactured by Nitto Boseki Co., Ltd., E-glass manufactured by Nippon Electric Glass Co., Ltd., ARG manufactured by Nippon Electric Glass Co., Ltd., and Alfiber manufactured by Asahi Glass Co., Ltd.

[0042] The plasma protective material 5 is disposed on the outer surface of the plasma-resistant structure 1 at the end of the intermediate member 4 that does not face the first member 2 and the second member 3. The end here refers to the surface of the intermediate member 4 that does not face the first member 2 and the second member 3 and faces the plasma protective material 5 or the plasma space. The plasma protective material 5 may be disposed on the outer periphery of the intermediate member 4 that does not face the first member 2 and the second member 3. Preferably, the plasma protective material 5 is disposed along the outer periphery of the intermediate member 4. This allows the plasma protective material 5 to cover the portions of the intermediate member 4 that do not face the first member 2 and the second member 3 (e.g., the end, outer surface side, outer periphery, inner surface side, and inner periphery of the intermediate member 4), blocking the path from the plasma space to the intermediate member 4. This increases the distance the plasma travels through the intermediate member 4, deactivating the plasma and reducing its impact on the intermediate member 4. The fibers of the plasma protective material 5 preferably extend along the outer periphery of the intermediate member 4.

[0043] The length of the plasma protective material 5 in the fiber extension direction is longer than the outer periphery of the intermediate member 4, and the fibers may be wound (tightly) around the outer periphery of the intermediate member 4 (including being wrapped around the intermediate member 4 once or multiple times as a result). Here, the plasma protective material 5 may be wound directly around the intermediate member 4, or preferably wound around the intermediate member 4 while applying pressure. This winding while applying pressure reduces the gaps (voids) between the fibers of the plasma protective material 5, thereby better insulating the intermediate member 4 from the plasma space. Alternatively, the plasma protective material 5 may be wound while sandwiched (in contact) between the first member 2 and the second member 3 (i.e., the plasma protective material 5 may be separated from the intermediate member 4). This sandwiching between the first member 2 and the second member 3 further reduces or eliminates the gaps (voids) between the fibers of the plasma protective material 5, thereby better insulating the intermediate member 4 from the plasma space. As a result, a plasma-resistant structure 1 with a long life can be provided.

[0044] In this specification, the term "fiber" refers to a filamentous substance, and its structure (shape) is not particularly limited. However, the diameter of the fibers of the plasma protective material 5 is preferably 5 μm to 0.2 mm, and more preferably 5 μm to 0.1 mm. It is preferable that the average fiber diameter is within these ranges from the viewpoints of stress relaxation and plasma resistance. The aspect ratio (length / diameter) of the fiber, although depending on the application, is preferably 1,000 to 2,200,000, more preferably 28,000 to 2,200,000, and even more preferably 140,000 to 1,200,000. This is because a longer fiber length (aspect ratio) tends to result in better plasma resistance, durability, and particle resistance.

[0045] The structure (shape) of the fiber-containing plasma protective material 5 is not particularly limited, but the plasma protective material 5 may be a fiber structure made of fibers. The fiber structure can be used as a single unit by entangling, twisting, knitting, or bonding multiple fibers, and the fiber structure has gaps (voids) between the fibers. This ensures stress relaxation against thermal stress and the like, making it possible to provide a plasma-resistant structure 1 with a long lifespan. Note that, as long as the plasma resistance of the fiber structure is not impaired, these gaps may be filled or partially filled with a binder such as a resin. This improves the mechanical strength of the fiber structure. As a result, it is possible to provide a plasma-resistant structure 1 with a long lifespan. The shape of the fiber structure is not particularly limited, but examples include thread, rope, layer, strip, sleeve, and ring-shaped versions of these. The fiber structure may be, for example, a twisted yarn, nonwoven fabric, woven fabric, or mesh-like structure, and may be composed of multiple components (fibers, etc.) with gaps (voids). The use of these fiber structures ensures stress relaxation properties against thermal stress and the like, thereby providing a plasma-resistant structure 1 with a long life. Known methods for manufacturing these fiber structures can be adopted depending on the intended use. For example, twisted yarns can be produced by twisting multiple fibers together, and nonwoven fabrics can be produced by, but are not limited to, dry or wet methods. The "voids" in the plasma protective material 5 are also not particularly limited as long as they can achieve the stress relaxation properties and long life described above. For example, the plasma protective material 5 may be formed by winding a single fiber made of the plasma-resistant material around the outer periphery of the intermediate member 4. In this case, too, the voids between the wound fibers can accommodate dimensional changes in the first member 2 and the second member 3 and relieve stress caused by the dimensional changes. As a result, a plasma-resistant structure 1 with a long life can be provided.

[0046] (Dimensions of Fibers in the Fiber Structure) The diameter of each fiber in the fiber structure is preferably 5 μm to 0.2 mm, more preferably 5 μm to 0.1 mm. The average fiber diameter within these ranges is preferable from the viewpoints of stress relaxation and plasma resistance. Furthermore, the aspect ratio of each fiber in the fiber structure is preferably 500 or more, more preferably 1000 or more, and even more preferably 8000 or more. When each fiber is a long fiber, the stress relaxation of the plasma protective material 5 is improved, resulting in a plasma-resistant structure 1 with a long life. The "diameter" of a fiber in this specification refers to the average area diameter (e.g., the average value of 20 fibers) calculated by calculating the cross-sectional area of ​​an arbitrary cross section perpendicular to the extension direction of the fiber imaged with a microscope (e.g., calculated using known software) and calculating the diameter of a circle having the same area as the cross-sectional area. Furthermore, the "length" of a fiber in this specification refers to, for example, the average length of 10 arbitrary fibers in the fiber structure.

[0047] Furthermore, the plasma protective material 5 (fiber structure) preferably includes fiber bundles. This means that the stress relaxation, strength, and ease of handling (including placement and removal) are improved by bundling fibers compared to when the material is composed solely of fibers. The fibers in the fiber bundles may be the same or different in material and size, but it is preferable that they are aligned in direction and have approximately the same size. The number of fibers in the bundle is not particularly limited and can be appropriately determined taking into account the thickness of the intermediate member 4, the fiber diameter, and the like. For example, the inorganic fiber bundles are preferably sandwiched (contacted) between the first member 2 and the second member 3. By being sandwiched between the first member 2 and the second member 3, the gaps (voids) between the fibers of the fiber bundles are compressed and reduced, isolating the intermediate member 4 from the plasma atmosphere and making the fiber bundles less likely to fall off. Selecting and setting the number of fibers in this way can extend the life of the plasma-resistant structure 1. Furthermore, it is preferable that the fibers in the fiber bundles are bonded to a degree that allows both shape maintenance and cushioning properties to be achieved. Using these fiber structures can provide a plasma-resistant structure 1 with a long life.

[0048] The extension direction of the fiber structure also preferably follows the outer periphery of the intermediate member 4. That is, the fiber bundles constituting the plasma protective material 5 also preferably extend along the outer periphery of the intermediate member 4. This allows the fiber structure to be inserted along the extension direction of the gap between the first member 2 and the second member 3, thereby blocking the path from the plasma space to the intermediate member 4, lengthening the distance the plasma takes to reach the intermediate member 4, deactivating the plasma, and suppressing its impact on the intermediate member 4. Furthermore, the direction of each fiber in the fiber bundle also preferably follows the outer periphery of the intermediate member 4. Since the fiber direction is aligned in this way, the fiber bundles serving as the plasma protective material 5 can be uniformly inserted between the first member 2 and the second member 3. This reduces the gaps between the first member 2 and the plasma protective material 5 and between the second member 3 and the plasma protective material 5, improving plasma resistance. As a result, the life of the plasma-resistant structure 1 can be extended.

[0049] In addition, the length of the plasma protective material 5 in the extending direction of the fiber structure may be longer than the outer periphery of the intermediate member 4, and the fiber structure may be wound around the outer periphery of the intermediate member 4 ( FIG. 3 ). Note that FIGS. 3A and 3B are examples of a top view and a perspective view of the plasma-resistant structure 1 when the plasma protective material 5 is wound around the outer periphery of the intermediate member 4.

[0050] Furthermore, the fiber bundles contained in the plasma protective material 5 preferably have a twisted yarn shape. If the twisted fibers can move relative to each other within the fiber bundle, both high strength and cushioning properties can be achieved. Furthermore, the high strength of the twisted yarn can increase the strength of the plasma protective material 5 and facilitate the removal of the plasma protective material 5 from the plasma-resistant structure 1. The twisted yarn can also relieve stress by loosening the fibers within the fiber bundle. The twisting method is not particularly limited, but can be 5 to 360 turns per meter, preferably 20 to 300 turns per meter. Twisting within the above range not only improves the strength and stress relaxation of the fiber bundle, but also balances the suppression of particle generation during plasma treatment. As a result, a plasma-resistant structure 1 with a long life can be provided. Here, "particles" primarily refers to small fragments generated from the plasma-resistant structure 1 during plasma treatment. Particles may become impurities on the held object W. For example, if the strength of the plasma protective material 5 is low, the fibers may be broken by plasma treatment and adhere to the held object W as particles. Furthermore, if the intermediate member 4 is not isolated or kept away from the plasma atmosphere by the plasma protection material 5, the intermediate layer may be deteriorated or destroyed by the plasma atmosphere, and may adhere to the workpiece W as particles.

[0051] The diameter of each fiber in the fiber bundle is preferably 5 μm to 0.2 mm, more preferably 5 μm to 0.1 mm, and even more preferably 5 μm to 20 μm. An average fiber diameter within these ranges is preferable from the viewpoints of stress relaxation and plasma resistance. Furthermore, the aspect ratio of each fiber in the fiber bundle is preferably 500 or more, more preferably 1000 or more, and even more preferably 8000 or more. When each fiber is a long fiber, the stress relaxation of the plasma protective material 5 is improved, resulting in a plasma-resistant structure 1 with a long life. The "diameter" of a fiber in this specification refers to the average area diameter (e.g., the average value of 20 fibers or fiber bundles) calculated by calculating the cross-sectional area of ​​an arbitrary cross section perpendicular to the extension direction of a fiber or fiber bundle imaged with a microscope (e.g., calculated using known software) and calculating the diameter of a circle having the same area as the cross-sectional area. Furthermore, the "length" of a fiber bundle in this specification refers to, for example, the average length of 10 arbitrary fibers in the fiber bundle.

[0052] The plasma protective material 5 does not have to be bonded to the first member 2, the second member 3, or the intermediate member 4; for example, a fiber structure (twisted yarn, mesh, nonwoven fabric, metal wire, etc.) may be pushed between the first member 2 and the second member 3 toward the intermediate member 4 as the plasma protective material 5.

[0053] When a fiber structure is pushed as a plasma protective material 5 from between the first member 2 and the second member 3 toward the intermediate member 4, the fiber structure may be compressed and placed between the first member 2 and the second member 3 (Case 1), or may be compressed and placed from the outer surface side of the intermediate member 4 toward the intermediate member 4 (Case 2).

[0054] An example of an embodiment (Case 1) in which the fiber structure is compressed and installed between the first member 2 and the second member 3 is when the diameter (hereinafter, "D") of the plasma protective material 5 (fiber structure, fiber bundle) when not installed between the first member 2 and the second member 3 (before installation or in an uninstalled state) is greater than the length between the first member 2 and the second member 3 (i.e., the thickness of the intermediate member 4; hereinafter, "H" is used for explanatory purposes). In the present disclosure, the plasma protective material 5 can preferably be installed between the first member 2 and the second member 3, with a length H smaller than the diameter D of the plasma protective material 5 (D > H). This reduces the gaps (voids) between the fibers in the fiber structure when the fiber structure is installed between the first member 2 and the second member 3, and isolates or distances the intermediate member 4 from the plasma atmosphere, achieving both stress relaxation and plasma resistance. As a result, a plasma-resistant structure 1 with a long life can be provided. The diameter D of the fiber structure can be defined as the diameter of the smallest circumscribing circle of the fiber structure in a cross-sectional view perpendicular to the extension direction of the fiber structure when not installed between the first member 2 and the second member 3. The circles in Figure 8 indicate examples of the smallest circumscribing circle of a fiber bundle (fiber structure). In the example of Figure 8, the diameters D of the fiber structure are 269 µm and 244 µm. In this non-installed state, the space factor of the fiber structure (area occupied by fibers in the smallest circumscribing circle / area of ​​the smallest circumscribing circle) is 63%, but the space factor of the fiber structure is preferably 20 to 80%, and more preferably 30 to 70%. Within this range, the fiber structure can be installed between the first member 2 and the second member 3. When installed, the gaps (voids) between the fibers in the fiber structure are reduced, and the intermediate member 4 is isolated or kept away from the plasma atmosphere. As a result, a plasma-resistant structure 1 with a long life can be provided. The space factor of the fiber structure in the present disclosure is the average value of the space factors calculated (for example, using publicly known software) from the area of ​​the smallest circumscribing circle and the area of ​​the smallest circumscribing circle, obtained by photographing any cross section perpendicular to the extension direction of the fiber structure using a microscope, for example, the average value of 20 cross-sectional images.

[0055] FIG. 9 shows a cross-sectional image of an electrostatic chuck (plasma-resistant structure 1) as a specific example of Case 1. A fiber bundle (fibrous structure) is wound around the outer periphery of an intermediate member 4 disposed between a first member 2 and a second member 3. In this example, the length H between the first member 2 and the second member 3 (the thickness of the intermediate member 4) is 100 μm, and the fiber diameter is 7 μm. Furthermore, the diameter D of one of the fiber structures (on the right side) in the non-installed state is 150 μm, and its space factor is 53%. This fiber structure is wound four times around the outer periphery of the intermediate member 4. In other words, the fiber structure is disposed between the first member 2 and the second member 3, each having a length H smaller than the diameter D of the fiber structure. This reduces the gaps between the fibers in the fiber structure, isolating or distancing the intermediate member 4 from the plasma atmosphere, and provides both cushioning and conformability. As a result, a plasma-resistant structure 1 with a long lifespan can be provided.

[0056] In the present disclosure, the ratio (diameter D of the fiber structure) / (length H between the first member 2 and the second member 3) is preferably 1 or greater, more preferably 1.2 or greater, and even more preferably 1.5 or greater. In other words, when compressed perpendicularly to its center (center of gravity), the fiber structure preferably has a diameter D that can deform to 83% of its length, more preferably 67% of its length. This allows for excellent cushioning and conformability, and such a plasma-resistant structure 1 reduces the gaps between the fibers in the fiber structure, allowing the intermediate member 4 to be isolated or kept away from the plasma atmosphere. As a result, a plasma-resistant structure 1 with a long lifespan can be provided. Note that D / H in FIG. 9 is 1.5.

[0057] An example of an embodiment (Case 2) in which the fiber structure is compressed from the outer surface side of the intermediate member 4 toward the intermediate member 4 is a case in which multiple fiber structures are overlappingly pressed along the outer periphery of the intermediate member 4. FIG. 10 shows a cross-sectional photograph of an electrostatic chuck (plasma-resistant structure 1) as a specific example of this embodiment. A fiber bundle (fiber structure) is wound around the outer periphery of the intermediate member 4, which is disposed between the first member 2 and the second member 3. In this example, the length H between the first member 2 and the second member 3 (the thickness of the intermediate member 4) is 565 μm, and the fiber diameter is 7 μm. Furthermore, the diameter D of the fiber structure in the unmounted state is 150 μm, and its space factor is 46%. This fiber structure is wound 32 times around the outer periphery of the intermediate member 4. In other words, the fiber structure is disposed between the first member 2 and the second member 3, which has a length H greater than the diameter D of the fiber structure, but compared to FIG. 9 , more fiber structures are overlapping from the outer surface side of the intermediate member 4 toward the intermediate member 4. This reduces the gaps between the fibers in the fiber structure, and isolates or keeps the intermediate member 4 away from the plasma atmosphere, thereby providing a plasma-resistant structure 1 with a long life.

[0058] Furthermore, in a cross-sectional view perpendicular to the extension direction of the fiber structure disposed in the plasma-resistant structure 1, it is preferable that at least a portion of the intermediate member 4 is isolated or distanced from the plasma atmosphere by a region where fibers are densely packed together. This allows for a long-life plasma-resistant structure 1 to be provided. Specifically, it is preferable that the fiber structure disposed between the first member 2 and the second member 3 has a space factor of 50% to 95% in any region (referred to as "region A" in FIG. 10 ) of (length H between the first member 2 and the second member 3) × (length 20 μm in the direction perpendicular to length H). It is more preferable that the space factor be 60% to 95%, and even more preferable that the space factor be 70% to 90%. This allows for the intermediate member 4 to be isolated or distanced from the plasma atmosphere while ensuring the stress relaxation properties of the fiber structure, thereby allowing for a long-life plasma-resistant structure 1 to be provided. In addition, in any region (referred to as "Region B") of (the length H between the first member 2 and the second member 3) × (80 μm length in the direction perpendicular to the length H), the space factor is preferably 50% or more and 95% or less. A space factor of 60% or more and 95% or less is more preferable, and a space factor of 70% or more and 90% or less is even more preferable. In any region (referred to as "Region C") of (the length H between the first member 2 and the second member 3) × (160 μm length in the direction perpendicular to the length H), the space factor is preferably 50% or more and 95% or less. A space factor of 60% or more and 95% or less is more preferable, and a space factor of 70% or more and 90% or less is even more preferable. As a result, the stress relaxation properties of the fiber structure are ensured while the region where fibers are densely packed is provided wider so as to isolate or distance the intermediate member 4 from the plasma atmosphere, thereby further isolating the intermediate member 4 from the plasma atmosphere. As a result, a plasma-resistant structure 1 with a long life can be provided.

[0059] FIG. 10 shows a specific example of this. This is a cross-sectional image showing an example in which the fiber bundle (fibrous structure) is compressed from the outer surface side of the intermediate member 4 toward the intermediate member 4. In this case, the space factor of the fiber structure in region A is 82%. This allows the intermediate member 4 to be isolated or kept away from the plasma atmosphere while ensuring the stress relaxation properties of the fiber structure, thereby providing a plasma-resistant structure 1 with a long life. Note that even in the case of FIG. 9 , the space factor of the fiber structure in region A0 was 76% (the space factor of the fiber structure before installation was 53%). Furthermore, in the example of FIG. 9 (Case 1), the fiber structure on the intermediate member 4 side is dense and the outer surface side is sparse. In other words, the space factor of the fiber structure on the intermediate member 4 side is greater than the space factor of the fiber structure on the outer surface side. This is mainly because the fiber structure closer to the intermediate member 4 is more compressed. In this case, the intermediate member can also be kept away from the plasma atmosphere, thereby providing a plasma-resistant structure 1 with a long life.

[0060] Figure 11 shows another specific example. In this case, the length H between the first member 2 and the second member 3 (the thickness of the intermediate member 4) was 70 µm, the diameter of the fibers of the fiber structure was 7 µm, and the number of turns (the number of times the fibers are wound) was 16. Furthermore, the diameter D of the fiber structure in the uninstalled state was 150 µm, and its space factor was 51%. The space factor of the fiber structure in region A was 83%. In other words, in this case too, the intermediate member 4 can be isolated or kept away from the plasma atmosphere while ensuring the stress relaxation properties of the fiber structure, thereby providing a plasma-resistant structure 1 with a long life.

[0061] The shapes of the fiber structure overlapped between the first member 2 and the second member 3 and the wound fiber bundle are not particularly limited, and may be spherical, elliptical, crescent, rectangular, or the like.

[0062] Furthermore, the outermost surface of the plasma protective material 5 (fiber structure) disposed on the outer surface side of the intermediate member 4 is preferably fixed. This prevents the fiber structure from fraying or breaking, and maintains the gaps (voids) between the fibers in the fiber structure in a compressed state. As a result, a plasma-resistant structure with a long life can be provided. The fixing method is not particularly limited, but examples include fixing between fibers (by knotting, entanglement, or hooking), fixing with a resin, and fixing with an inorganic material. A specific example of fixing with a resin is fixing by applying a reactive silicone resin (e.g., KE-103, manufactured by Shin-Etsu Chemical Co., Ltd.) to the outermost surface of the fiber structure and leaving it to harden at room temperature. Alternatively, the outermost surface of the fiber structure can be coated with a resin and fixed. For example, the fiber structure can be inserted into a heat-shrinkable tube (PTFE tube, SLW-AWG34HS, manufactured by Hagitec Co., Ltd.), heated and shrunk, and fixed. As a specific example of fixing with an inorganic material, the fiber structure can be fixed by applying a heated and melted inorganic material (e.g., solder, glass, etc.) or a solution containing an inorganic substance (e.g., an organometallic compound) to the outermost surface of the fiber structure, followed by cooling and solidifying the material, and then drying and solidifying the material, respectively. In this way, particles generated from the fiber structure can also be suppressed.

[0063] It is preferable that the plasma protective material 5 and the intermediate member 4 are at least partially separated, and more preferably partially separated and in close contact with each other (for example, in the electrostatic chuck 21 having a plasma-resistant structure shown in FIG. 5 , the side of the plasma protective material 25 that contacts the first member 22 and the side that contacts the second member 23 are separated from the outer peripheral portion 24 a of the bonding layer 24, which is the intermediate member). If the plasma protective material 5 is completely separated from the intermediate member 4, there is a risk of it falling off. However, by separating a portion of the plasma protective material 5 and in close contact with the other portion, stress relaxation can be improved. As a result, a plasma-resistant structure 1 with a long life can be provided.

[0064] Other embodiments of the present disclosure will be described below, in which the reference numerals of components that are the same as or similar to the components of the plasma-resistant structure 1 are numbered with 10, 20, 30, 40, etc. (i.e., for example, the plasma protection material 15 in FIG. 4 is the same as or similar to the plasma protection material 5). Also, in particularly preferred embodiments, the same or similar components may be given different names (for example, the edge ring portion 42 and the edge ring portion 43 in FIG. 6 correspond to the first member 2 and the second member 3, respectively, and may be made of a plasma-resistant material, but are given different names). Descriptions of these will be omitted as appropriate.

[0065] [Electrostatic Chuck 11] According to the present disclosure, an electrostatic chuck 11 having a plasma-resistant structure 1 as shown in FIG. 4 is provided. That is, in FIG. 4, the plasma-resistant structure 1 can be a holding member 12 that holds a workpiece W and a base 13 that holds the holding member 12. More specifically, the electrostatic chuck 11 includes the holding member 12 that holds the workpiece W, the base 13 that holds the holding member 12, a bonding layer 14 disposed between the holding member 12 and the base 13, and a plasma protective material 15 containing fibers. The plasma protective material 15 containing fibers is disposed on the outer surface side of the electrostatic chuck 11 at an end of the bonding layer 14. As will be described later, the plasma protective material 15 is resistant to plasma, and the plasma protective material 15 can be provided at a desired position on the electrostatic chuck 11 other than the bonding layer 14 (e.g., a heat insulating layer, a heat transfer layer, a conductive layer, an insulating layer, an O-ring, etc.).

[0066] (Holding member 12) The holding member 12 is used to adsorb and hold the object to be held W. The shape of the holding member 12 is not limited, and it can be made into a disk shape or a square shape to match the shape of the object to be held W. The dimensions of the holding member 12 can also be set appropriately to match the object to be held W. The "object to be held W" is also not limited, and can include, for example, workpieces such as wafers (silicon wafers, quartz wafers, SiC wafers, etc.), flat panel display (FPD) panels and substrates, metal members, film members, resin members (automotive interior materials, etc.), glass members, etc.

[0067] Examples of the holding member 12 include ceramic substrates (alumina, aluminum nitride, yttrium oxide, zirconium oxide, silicon carbide, etc.), resin substrates, and metal substrates made of aluminum, stainless steel, etc. Examples of resin substrates include polyimide, polyamide, polyamideimide, aromatic polyether ketone, and fluorine-based polymers from the viewpoints of plasma resistance and heat resistance. The holding member 12 may be a substrate made of two or more types of materials. From the viewpoints of plasma resistance and heat resistance, the holding member 12 is preferably a ceramic substrate, a resin substrate, or a composite substrate made of ceramic and resin.

[0068] The thickness of the holding member 12 is not particularly limited and can be in the range of 0.2 mm to 7 mm. Furthermore, when an internal electrode is provided in the holding member 12 as described below, the thickness of the holding member 12 may be in the range of 3 mm to 10 mm.

[0069] Furthermore, a plurality of protrusions may be provided on the surface of the holding member 12 that holds the workpiece W. By holding (attracting) the workpiece W on the upper surfaces of these protrusions, the contact area between the holding member 12 and the workpiece W is reduced. As a result, the quality of the workpiece W can be maintained and the life of the electrostatic chuck 11 can be extended. The number, arrangement, shape, height, dimensions, etc. of the protrusions are not particularly limited. From the viewpoint of maintaining the quality of the workpiece W, the shape of the protrusions is preferably disk-shaped or cylindrical, and the upper surface of each protrusion is preferably flat. If the shape and height of the protrusions are as described above, the holding (attracting) of the workpiece W can be stabilized, the quality of the workpiece W can be maintained at a high level, and an electrostatic chuck 11 with a longer life can be provided.

[0070] (Base 13) The base 13 holds the holding member 12 and also has a cooling function. The shape, material, thickness, etc. of the base 13 can be appropriately designed to suit the application. For example, the material of the base 13 can be ceramic, metal, or a combination thereof. Examples of ceramics include alumina, aluminum nitride, yttrium oxide, silicon carbide, etc., and examples of metals include, but are not limited to, aluminum, stainless steel, etc.

[0071] (Bonding Layer 14) The bonding layer 14 bonds together the various components, such as the holding member 12 and the base 13. The thickness (height) of the bonding layer 14 is not particularly limited, but is preferably 20 μm to 1000 μm, more preferably 50 μm to 800 μm, and even more preferably 100 μm to 500 μm. If the thickness of the bonding layer 14 is within this range, the bonding layer 14 can adequately withstand the stress caused by dimensional changes in the holding member 12 and the base 13 during heating, and can limit contact between the bonding layer 14 and the plasma atmosphere during the plasma treatment process. As a result, an electrostatic chuck 11 with a longer life can be provided.

[0072] Examples of materials for the bonding layer 14 include metals and adhesive materials (resins). From the viewpoint of workability, brazing materials (silver brazing, copper brazing, copper alloy brazing, aluminum brazing, nickel brazing, activated silver brazing, titanium brazing, solder materials, etc.) can be used as the metal, but are not limited to these. A more appropriate brazing material can be selected depending on the properties (thermal expansion, thermal conductivity, etc.) of the holding member 12 and the base 13 to be joined. Examples of adhesive materials include thermoplastic elastomers, thermosetting elastomers, epoxy resins, urethane resins, polyester resins, polyimide resins, polyamide resins, fluororesins, acrylic resins, silicone resins, urethane resins, and mixtures of these with fillers. From the viewpoint of adhesion and heat resistance, silicone resins, acrylic resins, epoxy resins, and mixtures of these with fillers are preferred, and silicone resins and mixtures of silicone resins with fillers are more preferred.

[0073] The bonding layer 14 may contain a thermally conductive filler. By including the thermally conductive filler, both adhesiveness and thermal conductivity can be achieved, thereby suppressing thermal deterioration of the bonding layer 14. As a result, it is possible to provide an electrostatic chuck 11 with a long life. Examples of the thermally conductive filler include, but are not limited to, metal, alumina, aluminum nitride, silicon carbide, boron nitride, carbon black, carbon nanotubes, and diamond. The amount, shape, and the like of the thermally conductive filler are also not particularly limited.

[0074] The present disclosure can also provide an electrostatic chuck 21 as shown in FIG. 5. Different bonding layers 24 may be used depending on the position in the surface direction. For example, different types of materials may be used for the central portion 24b and the peripheral portion 24a of the bonding layer 24 (FIG. 5). This allows the holding member 22 and the base 23 to withstand stress due to dimensional changes during heating.

[0075] (Plasma Protection Material 15) The plasma protection material 15 isolates or keeps the bonding layer 14 away from the plasma atmosphere in order to protect the bonding layer 14, and is preferably provided along the outer periphery of the bonding layer 14.

[0076] The plasma protection material 15 may be a combination of different materials. The plasma protection material 15 may also be a fibrous structure such as twisted yarn as described above.

[0077] (Protective Material) The electrostatic chuck 11 may further include a protective material (not shown) provided along the outer periphery of the plasma protective material 15. This protective material improves the strength of the plasma protective material 15 and can suppress particle generation from the plasma protective material 15. The protective material can also fix and hold the plasma protective material 15. For example, when the plasma protective material 15 is wound around the outer periphery of the bonding layer 14, a protective material may be provided to fix the end portion of the plasma protective material 15. This protective material may have elasticity that allows expansion and contraction. As a result, when the plasma protective material 15 is attached and fixed to the bonding layer 14 by the protective material without being wound around the outer periphery of the bonding layer 14, the plasma protective material 15 can be detached from the electrostatic chuck 11 without being unwound. Furthermore, for stress relief, it is preferable that at least a portion of the protective material is separated from the plasma protective material 15.

[0078] As the material of the protective material, an organic substance such as a resin can be used to hold and fix the plasma protective material 15. Examples of the resin include silicone resin, fluororesin, epoxy resin, polyimide resin, acrylic resin, etc. Furthermore, a plasma-resistant material can be used to protect the bonding layer 14 and the plasma protective material 15, and it is particularly preferable to use alumina, silicon carbide, metal oxide, etc.

[0079] The protective material can also be formed by applying a paste containing inorganic particles, a metal organic compound solution, a metal complex solution, or the like, followed by sintering, or by spraying an inorganic material.

[0080] (Others) In the electrostatic chuck 11 according to the present embodiment, an internal electrode (not shown) can be provided in the holding member 12 in order to apply a voltage to generate an electrostatic force (Coulomb force) to attract the workpiece W. Alternatively, such an internal electrode may be provided in the base 13.

[0081] The internal electrode is not particularly limited as long as it is made of a conductive material that can exert an electrostatic adsorption force when a voltage is applied. Examples of suitable internal electrodes include thin films made of metals such as copper, aluminum, gold, silver, platinum, chromium, nickel, and tungsten, and thin films made of at least two metals selected from the above metals. These conductive materials may also be incorporated into ceramic materials. Examples of such thin films of conductive materials include those formed by vapor deposition, plating, sputtering, thermal spraying, etc., and those formed by applying and drying a conductive paste. Specifically, metal foils such as copper foil, aluminum foil, nickel foil, and stainless steel foil are used.

[0082] Furthermore, it is preferable that the outermost periphery of the holding member 12 is located outside the outermost point of the plasma protective material 15 (or protective material), and it is more preferable that the outermost periphery of the base 13 is located outside the outermost point of the plasma protective material 15 (or protective material) ( FIG. 4 ). This is because deterioration of the plasma protective material 15 and the protective material due to plasma is suppressed. Furthermore, if the outermost periphery of the holding member 12 is located outside the outermost periphery of the base 13, this is preferable because it prevents interference between the base 13 and other members such as an edge ring 41 ( FIGS. 6 and 7 ) used together with the electrostatic chuck 11.

[0083] (Manufacturing Method and Use of Electrostatic Chuck 11) The electrostatic chuck 11 can be manufactured, for example, as follows. First, a holding member 12 and a base 13 are prepared. As described above, a metal such as copper is patterned on either the holding member 12 or the base 13 to form an internal electrode. Next, the holding member 12 and the base 13 are bonded via a bonding layer 14. This process is also performed in conventional electrostatic chuck manufacturing methods. In conventional electrostatic chucks, after the holding member and the base are bonded via a bonding layer, an O-ring or an adhesive (elastomer, acrylic rubber, silicone rubber, fluororubber, thermosetting resin, etc.) is provided. In contrast, in the embodiment of the present disclosure, the plasma protective material 15 as described above is provided on the outer surface of the electrostatic chuck 11 at the end of the bonding layer 14. Furthermore, a protective material is appropriately provided along the outer periphery of the plasma protective material 15 ( FIG. 4 ).

[0084] The electrostatic chuck 11 according to the present embodiment generates a Coulomb force by applying a voltage to internal electrodes embedded in the holding member 12 or the base 13, thereby attracting the workpiece W. For example, the electrostatic chuck 11 can be used to attract a wafer (workpiece W) in dry etching or CVD processes in semiconductor manufacturing processes. In particular, in an apparatus or method using plasma, the electrostatic chuck 11 according to the present embodiment can accommodate the holding member 12 or the base 13. Even if the holding member 12 or the base 13 is heated to a high temperature (e.g., 250°C) by plasma irradiation and expands, for example, if the plasma protective material 5 includes an inorganic fiber structure, voids are generated between the inorganic fibers, which can absorb stress due to the difference in expansion and contraction between the holding member 12 and the base 13. As a result, the electrostatic chuck 11 can have a long life. Furthermore, if the plasma protective material 15 is made of ceramics or the like mixed with the above-described fibers, the fibers act as aggregates for the ceramics, increasing the stress resistance of the plasma protective material 15. As a result, the stress resistance to external dimensional changes is improved, thereby extending the life of the electrostatic chuck 11.

[0085] Furthermore, compared to conventional electrostatic chucks, the manufacturing method of electrostatic chuck 11 generally differs in whether or not plasma protective material 15 is provided, and therefore, when repairing a conventional electrostatic chuck, it can be easily manufactured into electrostatic chuck 11 according to the present disclosure ( FIG. 3 ).

[0086] The present disclosure also provides an electrostatic chuck 31 as shown in FIG. 12( a). The electrostatic chuck 31 may have one or more through-holes 36 penetrating from the base 33 to the upper surface 32 a of the holding member 32. The function of the through-holes 36 is not particularly limited, but may be a flow path for heat transfer gas for adjusting the temperature of the held member W and the holding member 32, or may be a hole for storing lift pins P for lifting the held member W ( FIG. 12( b)). In these cases, the inner wall 36 a of the through-holes 36 (the electrostatic chuck 31, the holding member 32, the recess 33 a of the base 33, and the inner surface 34 b of the bonding layer 34) may be in contact with a plasma atmosphere. In this case, a plasma protection material 35 may be provided on the through-hole 36 on the inner surface 34 b side of the bonding layer 34 (which is also on the outer surface side of the electrostatic chuck 31). The plasma protection material 35 is preferably provided along the inner surface 34 b of the bonding layer 34, and may be provided so as to extend along the inner surface 34 b of the bonding layer 34. This blocks the path from the plasma space to the inner surface 34b of the bonding layer 34, lengthening the distance the plasma travels to reach the inner surface 34b of the bonding layer 34. This deactivates the plasma, thereby suppressing its effects on the bonding layer 34. As a result, a long-life electrostatic chuck 31 can be provided. For example, when a cylindrical through-hole 36 extending from the base 33 toward the holding member 32 is provided, the plasma protective material 35 is preferably disposed along the inner surface 34b of the bonding layer 34. If the through-hole 36 serves as a flow path for a heat transfer gas for adjusting the temperature of the held member W and the holding member 32, the shape of the plasma protective material 35 is not limited as long as this function is not impeded. For example, the shape of the plasma protective material 35 is not limited, but may be annular or arc-shaped, and the plasma protective material 35 may be disposed so that the heat transfer gas passes through gaps in the plasma protective material 35. Furthermore, if the through-hole 36 serves as a hole for accommodating the lift pins P for lifting the held member W, the shape of the plasma protective material 35 is not limited, but may be annular, arc-shaped, or the like, as long as this function is not impeded. The plasma protective material 35 can be installed by the following procedure: The plasma protective material 35 is inserted into a recess 33a provided in the base 33, and then an insulating member M that does not impede the passage of gas is inserted into the recess 33a, and the plasma protective material 35 is pushed up and fixed to the inner surface 34b of the bonding layer 34. At this time, the insulating member M and the plasma protective material 35 may be inserted at the same time.This method provides a simple manufacturing method and structure that does not impede the function of the electrostatic chuck 31, and as a result, an electrostatic chuck 31 with a longer life can be manufactured.

[0087] The shape of the insulating member M is not particularly limited as long as it does not impede gas permeation or the raising and lowering of the pins P. However, a cylindrical, sleeve-like, spiral, porous, or other shape that conforms to the through-hole 36 is preferred. This allows for both the durability of the insulating member M and the functionality of the electrostatic chuck 31. As a result, a long-life electrostatic chuck 31 can be provided. From the viewpoint of insulating properties, ceramic materials and resin materials are preferred as the material for the insulating member M. Examples of ceramic materials include oxides, hydroxides, and carbides containing at least one of yttrium, aluminum, zirconium, hafnium, calcium, magnesium, nickel, titanium, and silicon. Specifically, yttrium oxide, aluminum oxide, and aluminum nitride are preferred. This improves the durability of the insulating member M, thereby providing a long-life electrostatic chuck 31. Examples of resin materials include polyimide, polyamide, polyamideimide, aromatic polyether ketone, and fluorine-based polymers. From the viewpoint of plasma resistance, fluorine-based polymers are preferred, and polyimides are preferred from the viewpoint of insulating properties. As a result, the durability of the insulating member M is improved, and as a result, the electrostatic chuck 31 can be provided with a long life.

[0088] [Edge Ring 41] In addition, as an embodiment of the present disclosure, an edge ring 41 having a plasma-resistant structure as shown in FIGS. 6A and 6B is provided. FIGS. 6A and 6B are a perspective view and a cross-sectional view, respectively, of the edge ring 41. The edge ring 41 of the present disclosure is formed to surround the outer periphery of an electrostatic chuck and is preferably formed in a ring (annular) or arc shape. It is also used in a plasma processing process to uniformly perform plasma processing on a workpiece W, such as a wafer, attracted to the upper surface of the holding member of the electrostatic chuck ( FIG. 7 ). More specifically, in FIG. 6 , the edge ring 41 includes an edge ring portion 42, an edge ring portion 43, a bonding layer (intermediate member) 44 disposed between the edge ring portion 42 and the edge ring portion 43, and a plasma protection material 45 containing fibers. The plasma protection material 45 is disposed on the outer surface side of the bonding layer 44 of the edge ring 41. The plasma protection material 45 is resistant to plasma and can be provided at any desired position on the edge ring 41, other than the bonding layer 44.

[0089] (Edge ring portions 42, 43) The edge ring portions 42, 43 are portions that constitute the edge ring 41. Materials for the edge ring portions 42, 43 include, but are not limited to, semiconductors, conductors, insulators, and combinations of two or more of these. By combining these materials as desired, the dielectric properties can be controlled, enabling uniform plasma processing of a workpiece W, such as a wafer, attracted to the upper surface of the holding member of the electrostatic chuck. As a result, a long-life edge ring 41 can be provided. Similarly, the shapes of the edge ring portions 42, 43 and the bonding layer 44 are preferably, but not limited to, ring-shaped or arc-shaped. This allows the bonding layer 44 to be better protected from the plasma atmosphere, resulting in a long-life edge ring 41.

[0090] (Bonding Layer 44) The bonding layer 44 bonds together components such as the edge ring portion 42 and the edge ring portion 43. The thickness (height) of the bonding layer 44 is not particularly limited, but is preferably 20 μm to 1000 μm, more preferably 50 μm to 800 μm, and even more preferably 100 μm to 500 μm. If the thickness of the bonding layer 44 is within this range, the bonding layer 44 can adequately withstand the stress caused by dimensional changes in the edge ring portion 42 and the edge ring portion 43 during heating, and can limit contact between the bonding layer 44 and the plasma atmosphere during the plasma treatment process. As a result, an edge ring 41 with a longer lifespan can be provided.

[0091] The bonding layer 44 and the plasma protective material 45 may be the same as the bonding layer 14 and the plasma protective material 15. The edge ring 41 may also be provided with a protective material.

[0092] (Method and Use of Edge Ring 41) The edge ring 41 can be manufactured, for example, as follows. First, the edge ring portion 42 and the edge ring portion 43 are prepared. At this time, as described above, the edge ring portion 42 and the edge ring portion 43 are bonded via the bonding layer 44. This process is also performed in conventional edge ring manufacturing methods. In conventional edge rings, after the edge ring portion 42 and the edge ring portion 43 are bonded via the bonding layer, an O-ring or adhesive (elastomer, acrylic rubber, silicone rubber, fluororubber, thermosetting resin, etc.) is provided. In contrast, in the embodiment of the present disclosure, the plasma protective material 45 as described above is provided on the outer surface side of the edge ring 41 at the end of the bonding layer 44. Furthermore, a protective material (not shown) is appropriately provided along the outer periphery of the plasma protective material 45.

[0093] As described above, the edge ring 41 according to this embodiment has a long life. Furthermore, in a device or method using plasma, even if the edge ring portion 42 or the edge ring portion 43 becomes hot and expands due to plasma irradiation, for example, if the plasma protective material 45 includes an inorganic fiber structure, voids are generated between the inorganic fibers, which can absorb stress due to the difference in expansion and contraction between the edge ring portion 42 and the edge ring portion 43, thereby extending the life of the edge ring 41. Furthermore, if the plasma protective material 45 is made by mixing the above-described fibers with ceramics or the like, the fibers act as aggregates for the ceramics, increasing the stress resistance of the plasma protective material 45. As a result, stress resistance to external dimensional changes is improved, and the life of the edge ring 41 is extended.

[0094] Furthermore, compared to conventional edge rings, the manufacturing method of edge ring 41 generally differs in whether or not a plasma protection material 45 is provided, and therefore edge ring 41 according to the present disclosure can be easily manufactured when repairing a conventional electrostatic chuck.

[0095] [Plasma Processing Apparatus Component] Although not shown, one embodiment of the present disclosure may provide a plasma processing apparatus component having a plasma-resistant structure. Because plasma processing apparatuses are exposed to a plasma atmosphere, their housings and components installed inside the apparatus (electrostatic chucks, edge rings, apparatus inner walls, etc.) are also required to be plasma-resistant. For example, plasma processing apparatuses used in semiconductor device manufacturing processes are detachable to simultaneously load and unload workpieces such as wafers and maintain a vacuum inside, and O-rings or other sealants are used in the detachable components. Providing these detachable components with the plasma-resistant structure of the present disclosure can extend the life of the plasma processing apparatus. The "component" for a plasma processing apparatus in the present disclosure refers to a plasma processing apparatus that includes the plasma-resistant structure of the present disclosure. Examples include a housing and a detachable component. Furthermore, the plasma processing apparatus itself may include the plasma-resistant structure of the present disclosure as a part thereof. That is, one embodiment of the present disclosure may provide a plasma processing apparatus having a plasma-resistant structure.

[0096] When a crack exists in the plasma-resistant wall of a plasma processing apparatus, this wall can be made into the first member 2 and the second member 3, and the plasma protective material 5 and the intermediate member 4 can be inserted into the crack between the first member 2 and the second member 3 as a filler or adhesive (to bond the plasma protective material 5 to the first member 2 and the second member 3). In this way, the plasma protective material 5 of the present disclosure can also be used as a repair material.

[0097] (Method for Manufacturing and Repairing a Member for a Plasma Processing Apparatus) A member for a plasma processing apparatus (plasma-resistant structure 1) can be manufactured, for example, as follows. First, a first member 2 and a second member 3 are prepared. Then, as described above, an intermediate member 4 is placed between the first member 2 and the second member 3. This process is also performed in conventional manufacturing methods for members for plasma processing apparatuses. In conventional members for plasma processing apparatuses, the first member and the second member are joined via a bonding layer, and then an O-ring or adhesive (elastomer, acrylic rubber, silicone rubber, fluororubber, thermosetting resin, etc.) is provided. In contrast, in the embodiment of the present disclosure, the plasma protective material 5 as described above is provided on the outer surface side of the member for a plasma processing apparatus at the end of the intermediate member 4. For example, the plasma protective material 5 can be installed by winding a fiber structure having fibers around the outer periphery of the intermediate member 4. Furthermore, a protective material is appropriately provided around the outer periphery of the plasma protective material 5 (not shown). The repair method for a member for a plasma processing apparatus (plasma-resistant structure 1) includes a step of winding a fiber structure around the outer periphery of the intermediate member, as in the manufacturing method for a member for a plasma processing apparatus.

[0098] The plasma-resistant structure 1, electrostatic chuck 11, edge ring 41, and member for a plasma processing apparatus according to the present embodiment, configured as described above, include a first member 2, a second member 3, an intermediate member 4 disposed between the first member 2 and the second member 3, and a fiber-containing plasma protective material 5. At least one of the first member 2 and the second member 3 has plasma resistance, and the fiber-containing plasma protective material 5 is disposed on the outer surface side of the plasma-resistant structure 1 at the end of the intermediate member 4.

[0099] Furthermore, a fiber structure that is one embodiment of the present disclosure has fibers, and in a plasma-resistant structure 1 that includes a first member 2, a second member 3, and an intermediate member 4 arranged between the first member 2 and the second member 3, this fiber structure is arranged along the outer periphery of the intermediate member 4.

[0100] Furthermore, according to a manufacturing method of the plasma-resistant structure 1, which is one embodiment of the present disclosure, the method includes a step of placing an intermediate member between the first member 2 and the second member 3, and a step of winding a fiber structure around the outer periphery of the intermediate member 4.

[0101] Furthermore, according to a method for repairing a member for a plasma processing apparatus which is one embodiment of the present disclosure, the member for the plasma processing apparatus comprises a first member 2, a second member 3, and an intermediate member 4 arranged between the first member 2 and the second member 3, and this repair method includes a step of winding a fiber structure having fibers around the outer periphery of the intermediate member 4.

[0102] As described above, in the plasma-resistant structure 1, the plasma protective material 5 and the first member 2, etc., have plasma resistance, which increases the life of the intermediate member 4 and therefore the plasma-resistant structure 1. Furthermore, the voids in the plasma protective material 5 allow it to follow dimensional changes in, for example, the holding member 12 and the base 13 and relieve stress, thereby increasing the life of the electrostatic chuck 11. Furthermore, when the plasma protective material 5 is formed by mixing fibers into ceramics or the like, the fibers act as aggregates for the ceramics, which increases the strength of the plasma protective material 5 against stress. For example, the stress resistance to dimensional changes in the holding member 12 and the base 13 increases, thereby increasing the life of the electrostatic chuck 11.

[0103] In the plasma-resistant structure 1, electrostatic chuck 11, edge ring 41, member for a plasma processing apparatus, fiber structure, method for manufacturing the plasma-resistant structure 1, and method for repairing a member for a plasma processing apparatus according to the present embodiment, the plasma protective material 5 containing fibers may be disposed on the outer periphery of the intermediate member 4. The extending direction of the fibers may be along the outer periphery of the intermediate member 4.

[0104] In the plasma-resistant structure 1, electrostatic chuck 11, edge ring 41, member for plasma processing apparatus, fiber structure, manufacturing method for plasma-resistant structure 1, and repair method for member for plasma processing apparatus of the present embodiment, the plasma protective material 5 containing fibers may include a fiber structure made of fibers. In other words, the fiber structure may be formed from a plasma-resistant material similar to the plasma protective material 5.

[0105] In the plasma-resistant structure 1 , the electrostatic chuck 11 , the edge ring 41 and the member for a plasma processing apparatus according to the present embodiment, the extending direction of the fiber structure may be along the outer periphery of the intermediate member 4 .

[0106] Furthermore, in the plasma-resistant structure 1, electrostatic chuck 11, edge ring 41, and member for plasma processing apparatus, fiber structure, method for manufacturing plasma-resistant structure 1, and method for repairing member for plasma processing apparatus of this embodiment, intermediate member 4 may be a bonding layer.

[0107] Furthermore, in the plasma-resistant structure 1, electrostatic chuck 11, edge ring and member for plasma processing apparatus, fiber structure, method for manufacturing plasma-resistant structure 1, and method for repairing member for plasma processing apparatus of this embodiment, the length in the extension direction of the fiber may be longer than the outer periphery of intermediate member 4, and the fiber may be wound around the outer periphery of intermediate member 4.

[0108] Furthermore, in the present embodiment of the plasma-resistant structure 1, electrostatic chuck 11, edge ring 41, and member for plasma processing apparatus, fiber structure, method for manufacturing plasma-resistant structure 1, and method for repairing member for plasma processing apparatus, the length of the fiber structure in the extension direction may be longer than the outer periphery of intermediate member 4, and the fiber structure may be wound around the outer periphery of intermediate member 4.

[0109] In addition, in the plasma-resistant structure 1, electrostatic chuck 11, edge ring 41, and member for plasma processing apparatus, fiber structure, manufacturing method for plasma-resistant structure 1, and repair method for member for plasma processing apparatus of this embodiment, the fibers may be inorganic fibers.

[0110] Furthermore, in the plasma-resistant structure 1, electrostatic chuck 11, edge ring 41, and member for plasma processing apparatus, fiber structure, manufacturing method for plasma-resistant structure 1, and repair method for member for plasma processing apparatus of this embodiment, the fiber structure may include at least one of twisted yarn, nonwoven fabric, mesh, or woven fabric.

[0111] In the electrostatic chuck 11 of this embodiment, the first member 2 can be a holding member 12 that holds an object to be held, and the second member 3 can be a base 13 that holds the holding member 12.

[0112] Furthermore, in the electrostatic chuck 11 of this embodiment, the outermost periphery of the holding member 12 may be located outside the outermost point of the plasma protective material 5, and the outermost periphery of the base 13 may be located outside the outermost point of the plasma protective material 5.

[0113] It should be noted that the plasma-resistant structure 1, electrostatic chuck 11, edge ring 41, member for plasma processing apparatus, fiber structure, manufacturing method for plasma-resistant structure 1, and repair method for member for plasma processing apparatus according to this embodiment are not limited to the above-described aspects and combinations.

[0114] For example, the number of internal electrodes provided on the holding member 12 or the base 13 may be two, instead of one.

[0115] For example, an electrode may be provided on the edge ring portion 42 or inside the edge ring portion 42 .

[0116] For example, the edge ring 41 may further include one or more members in addition to the edge ring portion 42 and the edge ring portion 43, and an intermediate member 4 may be disposed between these members, and a plasma protection material 5 may be provided on the outer periphery of the intermediate member 4.

[0117] The present disclosure will be described in more detail below using examples and comparative examples.

[0118] [Method of manufacturing electrostatic chuck]

[0119] Example 1 An electrostatic chuck-shaped plasma-resistant structure (hereinafter referred to as an electrostatic chuck) was fabricated to have the configuration shown in Table 1. Specifically, a silicone adhesive (intermediate member, bonding layer) was applied to the upper surface of an aluminum base (second member, diameter 296 mm, thickness 30 mm) excluding a 20 mm periphery width, to a thickness of 0.2 mm after application. An alumina plate (diameter 297 mm, thickness 4 mm) was bonded to the upper surface of the base via the silicone adhesive as a holding member (first member). Next, an alumina fiber bundle (plasma protective material) made of the alumina fibers shown in Table 1 was wound around the outer peripheral edge of the silicone adhesive (bonding layer), the alumina plate, and the recess (the outer periphery of the bonding layer) surrounded by the base, and fixed between the alumina plate and the base. Then, by firing using a burner, the end point of the alumina fiber bundle was bonded to a portion of the alumina fiber bundle that overlapped it. The alumina fiber bundle was in contact with the bonding layer, and did not protrude beyond the outer peripheral edges of the base and the alumina plate. Thereafter, the substrate was left standing in a thermostatic chamber set at 120° C. for 2 hours to harden the silicone adhesive, thereby producing an electrostatic chuck.

[0120] Examples 2 and 3 Electrostatic chucks of Examples 2 and 3 were fabricated in the same manner as the electrostatic chuck of Example 1 so as to have the configuration shown in Table 1. Instead of wrapping around the recess surrounded by the outer peripheral end of the bonding layer, the alumina plate, and the base, alumina fiber bundles (fiber length 15 mm or 200 mm) shown in Table 1 were inserted along the entire outer periphery of the bonding layer so that three alumina fiber bundles were lined up next to each other and the extension direction of the alumina fiber bundles was along the outer periphery of the bonding layer.

[0121] Examples 4 to 13 Electrostatic chucks of Examples 4 to 13 were fabricated in the same manner as the electrostatic chuck of Example 1 so as to have the configurations shown in Table 1. In Table 1, "Fiber Bundle 1" represents CY-640D manufactured by Ceramic Wool Industries Co., Ltd., "Fiber Bundle 2" represents CY-1280D manufactured by Ceramic Wool Industries Co., Ltd., "Fiber Bundle 3" represents CT-2560D manufactured by Nitibi Co., Ltd., "Fiber Bundle 4" represents Naslon 12-100 / 2 manufactured by Nippon Seisen Co., Ltd., and "Fiber Bundle 5" represents T300-1000 manufactured by Toray Industries, Inc. (the same applies to Table 2).

[0122] Comparative Example 1 An electrostatic chuck of Comparative Example 1 was fabricated in the same manner as the electrostatic chuck of Example 1 so as to have the configuration shown in Table 1. The silicone adhesive was applied so as to have a thickness of 3.0 mm after application, and a fluororubber-based O-ring (AS568-277-D manufactured by NOK Corporation, wire diameter 3.5 mm, outer diameter 299 mm, inner diameter 292 mm) was used as the plasma protective material of Comparative Example 1, and was inserted into a recess surrounded by the outer peripheral end of the bonding layer, the alumina plate, and the base.

[0123] Comparative Example 2 An electrostatic chuck of Comparative Example 2 was fabricated in the same manner as the electrostatic chuck of Example 1 so as to have the configuration shown in Table 1. The plasma protective material of Comparative Example 2 was formed by spraying alumina particles (manufactured by Fujimi Co., Ltd., SURPREX AHP50, particle size 45 μm (manufacturer's nominal value)) from the outside of the bonding layer onto the outer peripheral edge of the bonding layer, the alumina plate, and the recess surrounded by the base.

[0124] Example 14 An edge ring was fabricated to have the configuration shown in Table 2. Specifically, a silicone adhesive (intermediate member, bonding layer; Shin-Etsu Chemical Co., Ltd., addition-curing silicone rubber KE-8101) was applied to the surface of a ring-shaped alumina plate (first member; outer diameter 340 mm, inner diameter 300 mm, thickness 16 mm) to a thickness of 0.2 mm after application, and on the surface of the alumina plate excluding a 10 mm width from the outer and inner peripheries. A ring-shaped aluminum plate (second member) of the same dimensions as the alumina plate was then attached to the top of the silicone adhesive. Next, alumina fiber bundles (plasma protective material) made of the alumina fibers shown in Table 2 were inserted along the outer and inner peripheries of the bonding layer into the recess surrounded by the outer and inner peripheries of the silicone adhesive (bonding layer), the alumina plate, and the aluminum plate. Then, the end points of the alumina fiber bundles were bonded to portions of the overlapping alumina fiber bundles by firing using a burner. The alumina fiber bundles were in contact with the bonding layer, and did not protrude from the outer and inner peripheral edges of the alumina plate and aluminum plate. The edge ring was then left to stand in a thermostatic chamber set at 120°C for 2 hours to harden the silicone adhesive.

[0125] Examples 15 and 16 The edge rings of Examples 15 and 16 were fabricated in the same manner as the edge ring of Example 14 so as to have the configuration shown in Table 2. Instead of inserting alumina fiber bundles made of alumina fibers into the outer and inner peripheral ends of the bonding layer as the plasma protective material, the alumina fiber bundles shown in Table 2 were inserted along the entire outer and inner peripheral ends of the bonding layer so that three alumina fiber bundles were lined up next to each other and the extension direction of the alumina fiber bundles was along the outer and inner peripheral sides of the bonding layer.

[0126] Examples 17 to 22 Edge rings of Examples 17 to 22 were fabricated in the same manner as the edge ring of Example 14 so as to have the configurations shown in Table 2.

[0127] Comparative Example 3 An edge ring of Comparative Example 3 was fabricated in the same manner as the edge ring of Example 14 so as to have the configuration shown in Table 2. In Comparative Example 3, the silicone adhesive was applied so as to have a thickness of 3.0 mm after application, and as the plasma protective material, a fluororubber-based O-ring (AS568-279-D manufactured by NOK Corporation, wire diameter 3.5 mm, outer diameter 337 mm, inner diameter 330 mm) was used on the outer periphery of the silicone adhesive, and a fluororubber-based O-ring (AS568-278-D manufactured by NOK Corporation, wire diameter 3.5 mm, outer diameter 311 mm, inner diameter 304 mm) was used on the inner periphery, and these were inserted into the outer and inner peripheral ends of the silicone adhesive (bonding layer) and into a recess surrounded by the alumina plate and aluminum plate.

[0128] Comparative Example 4 An edge ring of Comparative Example 4 was fabricated in the same manner as the edge ring of Example 14 so as to have the configuration shown in Table 2. The plasma protective material of Comparative Example 4 was formed by plasma spraying alumina particles (SURPREX AHP50 manufactured by Fujimi Co., Ltd., particle size 45 μm (manufacturer's nominal value)) from the outside and inside of the bonding layer toward the inner and outer peripheries of the bonding layer and the recess surrounded by the alumina plate and aluminum plate.

[0129] [Evaluation Method] (Measurement of Cross-Sectional Fiber Count After Installation) The cross-sectional fiber count of the electrostatic chucks and edge rings of Examples 1 to 22 after installation was measured under the conditions shown below. Specifically, the plasma protective material installed on each electrostatic chuck and edge ring was cut vertically, and the cross-sectional fiber count was measured from the resulting cross section using a microscope (Keyence Corporation, VHX-5000). (Evaluation of Plasma Resistance) The electrostatic chucks and edge rings of Examples 1 to 22 and Comparative Examples 1 to 4 were subjected to plasma treatment under the conditions shown below. The plasma protective material was then removed, and the edge of the silicone adhesive was observed at 100x magnification using a digital microscope (Keyence Corporation, VHX-6000). The evaluation of plasma resistance was based on the following criteria: "A+" if there was no change in the appearance of the silicone adhesive before and after plasma treatment; "A" if the outer or inner edge surface of the silicone adhesive retreated toward the inside of the silicone adhesive by a maximum of less than 2 mm; "B" if the outer or inner edge surface of the silicone adhesive retreated toward the inside of the silicone adhesive by a maximum of 2 mm or more but less than 5 mm; "C" if the silicone adhesive remained and the outer or inner edge surface of the silicone adhesive retreated toward the inside of the silicone adhesive by a maximum of 5 mm or more but less than 8 mm; and "D" if the outer or inner edge surface of the silicone adhesive retreated toward the inside of the silicone adhesive by 8 mm or more or the silicone adhesive had completely disappeared.

[0130] Plasma treatment device: Unity Me (manufactured by Tokyo Electron Ltd.) High frequency power output: 1000 W High frequency power frequency: 13.56 MHz Bias power output: None Degree of vacuum: 300 mTorr Oxygen gas flow rate: 400 sccm Fluorine gas flow rate: 200 sccm Mounting surface temperature: 25° C. Plasma treatment time: 24 hours

[0131] (Durability Evaluation) Durability was evaluated for the electrostatic chucks and edge rings of Examples 1 to 22 and Comparative Examples 1 to 4. Specifically, thermal cycles and plasma treatment were performed under the following conditions, and cracking or peeling of the bonding layer and plasma protective material of the electrostatic chuck and edge ring were evaluated. In the thermal cycle test, the electrostatic chuck and edge ring were placed in a thermostatic chamber (TCC-151W manufactured by Espec Corporation) set at 0°C, heated to 120°C at a heating rate of 10°C / min, held at 120°C for 30 minutes, and cooled to 0°C at a heating rate of 10°C / min. This process was repeated 200 times. The electrostatic chuck and edge ring were then removed from the thermostatic chamber and placed in a plasma device, where they were subjected to plasma treatment for 10 hours. The appearance of the electrostatic chuck and edge ring was then observed and evaluated. The durability of the electrostatic chuck and edge ring was evaluated as follows: "A" indicates that neither cracking nor peeling occurred in the bonding layer nor the plasma protective material; "B" indicates that cracking or peeling occurred only in the plasma protective material; "C" indicates that cracking or peeling occurred only in the bonding layer; and "D" indicates that cracking or peeling occurred in both the bonding layer and the plasma protective material. The plasma treatment conditions are shown below.

[0132] Plasma treatment device: Unity Me (manufactured by Tokyo Electron Ltd.) High frequency power output: 1000 W High frequency power frequency: 13.56 MHz Bias power output: None Degree of vacuum: 300 mTorr Oxygen gas flow rate: 400 sccm Fluorine gas flow rate: 200 sccm Mounting surface temperature: 25° C. Plasma treatment time: 10 hours

[0133] (Evaluation 1 of Particle Resistance) The particle resistance (particle generation ability) of the electrostatic chucks of Examples 1 to 13 and Comparative Examples 1 and 2 was evaluated. Specifically, a dummy wafer was placed on the mounting surface (holding member) of the electrostatic chuck, and the number of particles adhering to the surface that had been in contact with the dummy wafer mounting surface after plasma treatment was calculated. That is, a dummy wafer (diameter 300 mm, thickness 775 mm, made of silicon) was placed on the mounting surface of the electrostatic chuck, and then the electrostatic chuck was placed in a plasma device and subjected to plasma treatment for 24 hours. Thereafter, the electrostatic chuck was removed, the dummy wafer was lifted from the mounting surface, and the number and size of particles adhering to the surface that had been in contact with the dummy wafer mounting surface were measured using a wafer surface inspection device (WM-10, manufactured by TOPCON Corporation). The number of particles with a diameter of 0.5 μm or more but less than 1.0 μm and the number of particles with a diameter of 1.0 μm or more were counted. The particle resistance was evaluated as follows: "A" when the total number of particles was less than 1000; "B" when the number of particles was 1000 or more but less than 5000; "C" when the number of particles was 5000 or more but less than 10000; and "D" when the number of particles was 10000 or more. The plasma treatment conditions were as follows:

[0134] Plasma treatment device: Unity Me (manufactured by Tokyo Electron Ltd.) High frequency power output: 1000 W High frequency power frequency: 13.56 MHz Bias power output: None Degree of vacuum: 300 mTorr Oxygen gas flow rate: 400 sccm Fluorine gas flow rate: 200 sccm Mounting surface temperature: 25° C. Plasma treatment time: 24 hours

[0135] (Evaluation 2 of Particle Resistance) The particle resistance of the edge rings of Examples 14 to 22 and Comparative Examples 3 and 4 was evaluated. Specifically, the electrostatic chuck of Example 1 was installed on the inner periphery of the edge ring, a dummy wafer was placed on the mounting surface of the electrostatic chuck, and plasma processing was then performed. The number of particles adhering to the surface of the dummy wafer that had been in contact with the mounting surface was then calculated. That is, the electrostatic chuck of Example 1 was installed on the inner periphery of the edge ring, and a dummy wafer (diameter 300 mm, thickness 775 mm, made of silicon) was placed on the mounting surface of the electrostatic chuck to prepare an evaluation sample. The evaluation sample was then placed in a plasma device and subjected to plasma processing for 24 hours. After plasma treatment, the evaluation sample was removed, the dummy wafer was lifted from the mounting surface, and the number and size of particles adhering to the surface of the dummy wafer that had been in contact with the mounting surface were measured using a wafer surface inspection device (WM-10 manufactured by TOPCON Corporation). The number of particles with a diameter of 0.5 μm or more but less than 1.0 μm and the number of particles with a diameter of 1.0 μm or more were counted. The particle resistance was evaluated as follows: "A" if the total number of particles was less than 1,500; "B" if the number of particles was 1,500 or more but less than 5,500; "C" if the number of particles was 5,500 or more but less than 10,500; and "D" if the number of particles was 10,500 or more. The plasma treatment conditions were as follows:

[0136] Plasma treatment device: Unity Me (manufactured by Tokyo Electron Ltd.) High frequency power output: 1000 W High frequency power frequency: 13.56 MHz Bias power output: None Degree of vacuum: 300 mTorr Oxygen gas flow rate: 400 sccm Fluorine gas flow rate: 200 sccm Mounting surface temperature: 25° C. Plasma treatment time: 24 hours

[0137]

[0138]

[0139] (Overall Evaluation) As shown in Tables 1 and 2, the plasma-resistant structures (electrostatic chuck, edge ring) of the present disclosure, which are equipped with a plasma protective material containing fiber, exhibit a good balance of plasma resistance, durability, and particle resistance, and have an overall longer lifespan, compared to the plasma-resistant structures of Comparative Examples 1 to 4, which do not contain fiber.

[0140] Comparative Examples 1 and 3, which included an O-ring made of fluororubber, were highly durable but vulnerable to plasma. In the case of twisted yarns like those in the examples, multiple fibers are entangled without being bonded, which is thought to have alleviated stress by changing their positional relationship when stress was applied. In contrast, Comparative Example 3, due to its integrated structure (bulk body), was unable to deform when its positional relationship changed, which is thought to have resulted in cracking. Furthermore, Comparative Examples 2 and 4, in which the plasma protective material was formed by plasma spraying alumina particles instead of fibers, not only had poor particle resistance, but were also vulnerable to thermal stress, particularly in terms of durability, and the plasma protective material cracked after evaluation.

[0141] The results of Examples 1 to 5 and 14 to 18 show that the longer the fiber length (aspect ratio), the better the evaluation. It was also found that a short fiber length not only resulted in poor plasma resistance, but also in poor particle resistance. Good results were obtained for durability, regardless of fiber length.

[0142] The results of Examples 6 to 9 and 20 to 22 showed that excessive twisting reduces durability and plasma resistance. This is thought to be due to the fact that stress relaxation becomes difficult when the fibers are fixed, and that insufficient conformability to the contact surface increases gaps between the base and holding member and the plasma protective material. On the other hand, it was found that plasma resistance and particle resistance decrease when the twisting count is low. The above suggests that the preferred twisting count (converted to one meter) is 20 to 300 times. In other words, by setting the twisting count within the above range, stress relaxation and particle generation suppression can both be achieved.

[0143] The results of Examples 10 and 11 show that plasma resistance decreased as the fiber bundle became thicker (as the number of fibers in the fiber bundle increased). This is thought to be because the increased number of fibers reduces the range of fiber movement, making stress relaxation more difficult, resulting in larger gaps between the base and the fiber bundle and between the holding member and the fiber bundle.

[0144] In Example 12, which used SUS fiber, the plasma resistance was low. This is thought to be due to the low resilience of the material, which led to the formation of a gap between the base and the holding member. The durability was good, but this is thought to be due to the high stress relaxation properties of the fiber itself. In Example 13, which used carbon fiber, the durability and particle resistance were low. This is thought to be due to the high resilience of the fiber, which is easily broken by even a small amount of stress.

[0145] [Electrostatic chuck manufacturing method 2]

[0146] Example 23 For Example 23 ( FIG. 9 ), an electrostatic chuck-shaped plasma-resistant structure (hereinafter referred to as an electrostatic chuck) was fabricated to have the configuration shown in Table 3. Specifically, a silicone adhesive (intermediate member, bonding layer) was applied to the upper surface of an aluminum base (second member, 100 mm diameter, 30 mm thickness) except for the outer periphery, to a thickness of 100 μm after application. An alumina plate (100 mm diameter, 4 mm thickness) was bonded to the upper surface of the base via the silicone adhesive as a holding member (first member). Next, an alumina fiber bundle (fiber structure, plasma protective material, space factor of 53% when not installed) made of the alumina fibers shown in Table 3 was wound four times around the outer periphery of the silicone adhesive (bonding layer), the alumina plate, and the recess (outer periphery of the bonding layer) surrounded by the adhesive-free portion of the base, and fixed between the alumina plate and the base. Then, the end of the alumina fiber bundle was bonded to the overlapping portion of the alumina fiber bundle by firing using a burner. Thereafter, the substrate was left standing in a thermostatic chamber set at 120° C. for 2 hours to harden the silicone adhesive, thereby producing an electrostatic chuck.

[0147] For Example 24 ( FIG. 10 ), an electrostatic chuck was produced in the same manner as in Example 23, except that the thickness of the silicone adhesive, the space factor of the alumina fiber bundle in the non-installed state, and the number of windings of the alumina fiber bundle were different so as to have the configuration shown in Table 3. In Example 24, the thickness of the silicone adhesive was 565 μm, the space factor of the alumina fiber bundle in the non-installed state was 46%, and the number of windings of the alumina fiber bundle was 32.

[0148] Example 25 For Example 25, an electrostatic chuck was produced in the same manner as in Example 23, except that the thickness of the silicone adhesive, the space factor of the alumina fiber bundle in the non-installed state, and the number of windings of the alumina fiber bundle were different so as to have the configuration shown in Table 3. In Example 25, the thickness of the silicone adhesive was 70 μm, the space factor of the alumina fiber bundle in the non-installed state was 51%, and the number of windings of the alumina fiber bundle was 16.

[0149] (Examples 26 to 28) For Examples 26 to 28, electrostatic chucks were produced in the same manner as in Example 23, except that the diameter of the alumina fiber bundle, the space factor of the alumina fiber bundle in an unmounted state, and the number of windings of the alumina fiber bundle were different so as to have the configurations shown in Table 3. In Examples 26 to 28, the diameter of the alumina fiber bundle was 120 μm, the space factor of the alumina fiber bundle in an unmounted state was 44%, and the number of windings of the alumina fiber bundle in Examples 26 to 28 was 1 time, 2 times, and 10 times, respectively.

[0150] [Evaluation Method] (Long-Term Plasma Resistance Evaluation) The electrostatic chucks of Examples 23 to 28 were subjected to plasma treatment under the conditions shown below. The presence or absence of damage to the plasma protective material was then observed at 100x magnification using a digital microscope (Keyence VHX-6000). Next, the plasma protective material was removed from these electrostatic chucks, and the edge of the silicone adhesive was observed at 100x magnification using the digital microscope. The long-term plasma resistance evaluation was rated as follows: "A" if there was no change in the appearance of the silicone adhesive before and after plasma treatment; "B" if the outer or inner peripheral end surface of the silicone adhesive receded into the silicone adhesive by a maximum of less than 2 mm; "C" if the outer or inner peripheral end surface of the silicone adhesive receded into the silicone adhesive by a maximum of 2 mm or more but less than 8 mm; and "D" if one or more of the following conditions were met: the outer or inner peripheral end surface of the silicone adhesive receded into the silicone adhesive by 8 mm or more; the silicone adhesive was lost; or damage to the fiber structure was observed.

[0151] Plasma treatment device: Unity Me (Tokyo Electron Ltd.) High frequency power output: 1000 W High frequency power frequency: 13.56 MHz Bias power output: None Degree of vacuum: 300 mTorr Oxygen gas flow rate: 400 sccm Fluorine gas flow rate: 200 sccm Mounting surface temperature: 25°C Plasma treatment time: 48 hours Intermediate member: Silicone adhesive

[0152]

[0153] Examples 23 and 25 show that when the fiber structure is compressed and placed between the first and second members (Case 1), the higher the D / H value, the greater the effect of isolating the silicone adhesive (intermediate member) from the plasma atmosphere.

[0154] Although Examples 26 and 27 differed slightly in the diameter and D / H of the alumina fiber bundle (fibrous structure) compared to Example 23, the length H between the first and second members was the same, with the most significant difference being the number of windings of the fibrous structure. The number of windings is thought to be approximately proportional to the overlap length of the fibrous structure in the direction facing the silicone adhesive in the fibrous structure after installation. From the results of the long-term plasma resistance evaluation, Examples 23, 27, and 26 were ranked in descending order of effectiveness in isolating or distancing the silicone adhesive in the fibrous structure from the plasma atmosphere. The space factors of the fibrous structure in regions A to C (corresponding to regions A to C in Figure 10, respectively) of Example 23 were all high, at 73% or higher. Meanwhile, the space factors of the fibrous structure in region B of Example 26 were 58%, and the space factors of the fibrous structure in region C were 29%. In other words, the area in Example 23 where fibers are densely packed together (the length over which the fiber structure overlaps in the direction facing the silicone adhesive) is larger than this area in Examples 26 and 27, which increases the length over which the plasma atmosphere reaches the silicone adhesive, and as a result, it is thought that a high effect of isolating or keeping the silicone adhesive away from the plasma atmosphere was achieved (a similar effect can be inferred from Example 24).

[0155] In Example 28, the diameter D of the fiber structure and the length H between the first and second members were the same as in Examples 26 and 27, with the most significant difference being the number of windings of the fiber structure. Therefore, in the results of the long-term plasma resistance evaluation, the effectiveness of the fiber structure in isolating or distancing the silicone adhesive from the plasma atmosphere was ranked in descending order of effectiveness for Examples 28, 27, and 26. The space factors of the fiber structure in regions A to C of Example 28 were all high, at 85% or higher, and no change in the appearance of the silicone adhesive was observed in the results of the long-term plasma resistance evaluation. However, damage was observed in part of the fiber structure. The space factor of the fiber structure in region A of Example 28 was high at 96%, and the gaps between the fibers were minimal. This is thought to have prevented the fiber structure from withstanding the thermal stress continuously generated during the long-term plasma resistance evaluation, resulting in partial damage to the fiber structure. Furthermore, the results of Examples 26 and 27 demonstrate that the effect of isolating the silicone adhesive (intermediate member) from the plasma atmosphere can be achieved if at least a portion of the fiber structure has a region where fibers are densely packed together.

[0156] DESCRIPTION OF SYMBOLS 1, 1a, 11, 21, 31, 41 Plasma-resistant structure (electrostatic chuck, edge ring) 2, 2a, 12, 22, 32, 42 First member (holding member, edge ring portion) 32a Upper surface of holding member 3, 13, 23, 33, 43 Second member (base, edge ring portion) 33a Recess of second member 4, 14, 24a, 24b, 34, 44 Intermediate member (bonding layer) 34b Inner surface of bonding layer 5, 15, 25, 35, 45, 45a, 45b Plasma protection material 36 Penetration portion 36a Inner wall of penetration portion M Insulating member P Lifting pin W Helded object

Claims

1. A plasma-resistant structure comprising a first member, a second member, an intermediate member disposed between the first member and the second member, and a plasma protective material containing fibers, wherein at least one of the first member and the second member has plasma resistance, and the plasma protective material containing fibers is disposed on the outer surface side of the plasma-resistant structure at an end of the intermediate member.

2. The plasma-resistant structure according to claim 1, wherein the plasma protective material containing the fibers is disposed on the outer periphery of the intermediate member.

3. The plasma-resistant structure according to claim 1, wherein the fibers extend along the outer periphery of the intermediate member.

4. The plasma-resistant structure according to claim 1, wherein the plasma protective material containing fibers includes a fiber structure made of fibers.

5. The plasma-resistant structure according to claim 4, wherein the direction in which the fiber structure extends is along the outer periphery of the intermediate member.

6. The plasma-resistant structure according to claim 1, wherein the intermediate member is a bonding layer.

7. A plasma-resistant structure according to claim 1, wherein the length of the fibers in the extending direction is longer than the outer periphery of the intermediate member, and the fibers are wound around the outer periphery of the intermediate member.

8. A plasma-resistant structure according to claim 4, wherein the length of the fiber structure in the extending direction is longer than the outer periphery of the intermediate member, and the fiber structure is wound around the outer periphery of the intermediate member.

9. The plasma-resistant structure of claim 1, wherein the fibers are inorganic fibers.

10. The plasma-resistant structure of claim 4, wherein the textile structure comprises at least one of a twisted yarn, a nonwoven fabric, a mesh, or a woven fabric.

11. An electrostatic chuck comprising the plasma-resistant structure according to claim 1, wherein the first member is a holding member that holds an object to be held, and the second member is a base that holds the holding member.

12. The electrostatic chuck according to claim 11, wherein the outermost periphery of the holding member is located outside the outermost point of the plasma protection material.

13. An electrostatic chuck according to claim 11, wherein the outermost periphery of the base is located outside the outermost point of the plasma protection material.

14. An edge ring comprising the plasma-resistant structure according to claim 1.

15. A member for a plasma processing apparatus, comprising the plasma-resistant structure according to claim 1.

16. A fiber structure having fibers, characterized in that in a plasma-resistant structure comprising a first member, a second member, an intermediate member disposed between the first member and the second member, and the fiber structure, the intermediate member is disposed along the outer periphery of the intermediate member.

17. A method for manufacturing a plasma-resistant structure comprising a first member, a second member, an intermediate member disposed between the first member and the second member, and a fiber structure having fibers, the method including the steps of: disposing the intermediate member between the first member and the second member; and winding the fiber structure around the outer periphery of the intermediate member.

18. A method for repairing a member for a plasma processing apparatus comprising a first member, a second member, and an intermediate member disposed between the first member and the second member, the method including a step of winding a fiber structure having fibers around the outer periphery of the intermediate member.

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