High-dielectric thermally conductive composition and high-dielectric thermally conductive member

Abstract

Provided is a high-dielectric heat conductive member having electric insulation and moderate flexibility, high heat conductivity and high dielectric properties, and a high-dielectric heat conductive composition capable of forming the high-dielectric heat conductive member. The high-dielectric heat conductive composition contains a resin (A) and a heat conductive filler (B), the content of the heat conductive filler (B) is 50 to 88% by volume of the entire composition, and the heat conductive filler (B) contains a first heat conductive filler (b1) having a volume resistivity of 1.0 x 10 8 Ω·cm, and the content of the first heat conductive filler (b1) is 7 to 35% by volume of the entire composition.

Description

Technical Field

[0001] The present invention relates to a high dielectric thermally conductive composition and a high dielectric thermally conductive component formed therefrom, and more specifically, to a thermally conductive component for suppressing temperature rise of a substrate being etched in a semiconductor etching apparatus and a thermally conductive composition forming therefrom. Background Technology

[0002] In semiconductor etching apparatuses, a thermally conductive component is disposed between the outer periphery of the chuck mechanism portion that holds the substrate to be processed, such as a wafer, and an edge ring disposed on the outer periphery of the substrate to dissipate heat transferred to the edge ring due to the etching operation. The thermally conductive component is, for example, obtained by mixing a thermally conductive filler such as an alumina metal oxide or nitride into a rubber substrate such as silicone, and then curing or molding it. This thermally conductive filler has high thermal conductivity but a low relative dielectric constant, thus resulting in low dielectric properties as a thermally conductive component.

[0003] As a chuck mechanism constituting a semiconductor etching apparatus, electrostatic chucks are widely used. In electrostatic chucks, dielectric materials with high relative permittivity are used in components other than thermally conductive parts. Therefore, if the thermally conductive parts can also be given the same relative permittivity, the difference in relative permittivity between components within the etching apparatus becomes smaller, potentially improving the yield during etching operations. Thus, as a technique for imparting high relative permittivity to thermally conductive parts, for example, Patent Document 1 proposes a technique that combines and mixes high-dielectric-constant particles such as barium titanate and thermally conductive particles such as nitrides in a polymer substrate to form a high-dielectric-insulating heat sink that simultaneously possesses high relative permittivity and heat dissipation properties.

[0004] [Existing Technical Documents] [Patent Literature] [Patent Document 1] Japanese Patent Application Publication No. 2013-8724 Summary of the Invention

[0005] [The problem the invention aims to solve] However, in Patent Document 1, high-dielectric-constant microparticles such as barium titanate are used to obtain a high relative permittivity. However, due to the poor thermal conductivity of high-dielectric-constant microparticles, the resulting sheet (thermal conductive component) obtained by mixing high-dielectric-constant microparticles and thermally conductive microparticles suffers from reduced thermal conductivity. Therefore, in semiconductor etching apparatuses utilizing high-frequency currents, which operate in a demanding environment with high heat dissipation requirements, it is undesirable for the thermal conductivity of the thermal conductive component to decrease. Instead, it is desirable to have high thermal conductivity while possessing a relative permittivity as high as that of the chuck mechanism and its surrounding components in the semiconductor etching apparatus, as well as a sufficiently low dielectric loss tangent (tanδ).

[0006] Furthermore, in semiconductor etching apparatuses, to ensure uniform surface treatment of the wafer, it is undesirable to energize the edge ring and chuck mechanism; instead, it is desirable for the heat-conducting components to be electrically insulating. Additionally, for the heat-conducting components disposed between the outer periphery of the chuck mechanism portion of the semiconductor etching apparatus and the edge ring located on the outer periphery of the substrate being processed, appropriate flexibility is required for seamless mounting between the outer periphery and the edge ring.

[0007] The present invention was made in view of the following actual situation, and its object is to provide a high dielectric thermally conductive component having electrical insulation and moderate flexibility, as well as high thermal conductivity and high dielectric properties, and a high dielectric thermally conductive composition capable of forming the high dielectric thermally conductive component.

[0008] [Methods for solving the problem] To achieve the above objectives, the high dielectric thermal conductivity composition of the present invention comprises a resin (A) and a thermally conductive filler (B). The content of the thermally conductive filler (B) is 50-88% by volume of the total composition, and the thermally conductive filler (B) comprises a material with a volume resistivity of 1.0 × 10⁻⁶ to 1.0 × 10⁻⁶. 8 The first thermally conductive filler (b1) is present in Ω·cm. In the high dielectric thermally conductive composition of the present invention, the content of the first thermally conductive filler (b1) is 7 to 35% by volume of the total composition. Such a high dielectric thermally conductive composition can be formed into a cured product in which the thermally conductive filler is filled in the resin. The cured product has electrical insulation and moderate flexibility, and can be used as a thermally conductive component disposed between the outer periphery of the chuck mechanism of a semiconductor etching apparatus and the edge ring disposed on the outer periphery of the substrate being processed. In addition, the cured product can be a high dielectric thermally conductive component that has both high thermal conductivity and high dielectric properties (also referred to as high dielectric in this specification, meaning high relative permittivity and low dielectric loss tangent tanδ). Even when used in a semiconductor etching apparatus as a thermally conductive component disposed between the outer periphery of an electrostatic chuck on which a substrate such as a wafer is placed and the edge ring disposed on the outer periphery of the substrate being processed, the difference in relative permittivity with other components can be reduced. Furthermore, since cured materials with high dielectric loss tangent tanδ also generate a lot of heat due to the electric field, they cannot function fully as heat-conducting components in devices that generate high-frequency electric fields. However, the cured material of the high dielectric thermal conductivity composition of the present invention has a low dielectric loss tangent tanδ, and is therefore suitable for use in semiconductor etching devices and the like that that generate high-frequency electric fields.

[0009] The high dielectric thermal conductivity component of the present invention is composed of a cured product of the aforementioned high dielectric thermal conductivity composition. This high dielectric thermal conductivity component is disposed between the edge ring of the outer periphery of the substrate being processed in a semiconductor etching apparatus and the outer periphery of the electrostatic chuck on which the substrate is placed. It has a relative permittivity of 8 or higher, a thermal conductivity of 1.0 W / m·K or higher, and a dielectric loss tangent tanδ of 0.01 or lower. The resin (A) is a polyorganosiloxane. The high dielectric thermal conductivity component of the present invention, when having a relative permittivity of 8 or higher, a thermal conductivity of 1.0 W / m·K or higher, and a dielectric loss tangent tanδ of 0.01 or lower, exhibits sufficiently high relative permittivity and thermal conductivity, and sufficiently small dielectric loss tangent tanδ. Therefore, it is suitable for use as a thermally conductive component between the outer periphery of the electrostatic chuck on which a substrate such as a wafer is placed and the edge ring of the outer periphery of the substrate being processed in a semiconductor etching apparatus that generates a high-frequency electric field.

[0010] Preferably, in the high dielectric thermal conductivity component of the present invention, the average particle size D of the first thermally conductive filler (b1) is... 50 The particle size is 0.1–100 μm. The high dielectric thermal conductivity component of this invention has an average particle size D in the first thermally conductive filler (b1). 50 Within the range of 0.1–100 μm, the relative permittivity exhibits a relatively high value. Furthermore, the first thermally conductive filler (b1) is more preferably characterized by an average particle size D. 50 The particle size is 10–40 μm. Additionally, the average particle size D of the first thermally conductive filler (b1) is... 50 Within the range of 10–40 μm, both the volume resistivity and relative permittivity exhibit relatively high values. It should be noted that the average particle size D in this specification... 50 In a volumetric cumulative particle size distribution, the particle size D refers to the particle size D where the cumulative particle volume from the smaller particle size side is 50% of the total particle volume. 50 For example, values ​​determined by laser diffraction and scattering.

[0011] In the high dielectric thermally conductive component of the present invention, the first thermally conductive filler (b1) is preferably made of at least one material selected from the group consisting of metallic silicon and silicon carbide. Since the first thermally conductive filler (b1) is made of these materials, the high dielectric thermally conductive component of the present invention can form a thermally conductive sheet with a sufficiently high relative permittivity, suitable for use in semiconductor etching apparatuses that generate high-frequency electric fields, etc.

[0012] In the high dielectric thermally conductive component of the present invention, the aforementioned thermally conductive filler (B) further comprises a volume resistivity exceeding 1.0 × 10⁻⁶. 8The second thermally conductive filler (b2) has an Ω·cm content, and its content is preferably 40 to 80% by volume of the entire composition. The second thermally conductive filler (b2) is preferably composed of at least one material selected from the group consisting of alumina, aluminum nitride, boron nitride, silicon nitride, diamond, aluminum hydroxide, and magnesium oxide.

[0013] As a high-dielectric-thermal-conducting component of a cured composition containing such a second thermally conductive filler (b2), it is possible to achieve both high thermal conductivity and high relative permittivity without deteriorating volume resistivity and hardness. The volume resistivity of the high-dielectric-thermal-conducting component of the present invention is preferably 1.0 × 10⁻⁶. 9 With a hardness of Ω·cm or higher, and preferably Asker C5 to 75 (SRIS 0101 standard, 23±2℃), this configuration is suitable for use in semiconductor etching devices that generate high-frequency electric fields.

[0014] In the semiconductor etching apparatus of the present invention, the aforementioned high dielectric and thermally conductive component is assembled. Since the aforementioned high dielectric and thermally conductive component has both high thermal conductivity and high relative permittivity, the difference in relative permittivity between the components in the etching apparatus becomes smaller, which may help to improve the yield during etching operations.

[0015] [The effects of the invention] According to the present invention, a high-dielectric thermally conductive component having electrical insulation and moderate flexibility, as well as high thermal conductivity and high dielectric properties, and a high-dielectric thermally conductive composition capable of forming the high-dielectric thermally conductive component can be provided. The high-dielectric thermally conductive component thus formed can exert sufficient heat dissipation performance even in harsh environments such as semiconductor etching apparatuses utilizing high-frequency currents where a large amount of heat needs to be dissipated. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of a semiconductor etching apparatus according to one embodiment of the present invention. Detailed Implementation

[0017] The high dielectric thermally conductive composition and high dielectric thermally conductive component of the present invention will be described in detail below.

[0018] First, the high dielectric thermal conductivity composition of the present invention will be described. The high dielectric thermal conductivity composition of the present invention comprises at least a resin (A) and a thermally conductive filler (B). Hereinafter, each component contained in the high dielectric thermal conductivity composition of the present invention will be described.

[0019] (Resin (A)) First, the resin (A) will be described. The resin (A) constituting the high dielectric thermal conductivity composition of the present invention is a polymeric material that can be filled and cured. In the high dielectric thermal conductivity composition of the present invention, the resin (A) is preferably, for example, epoxy resin, silicone resin, phenolic resin, polyethylene resin, polypropylene resin, polyurethane resin, polyimide resin, polyamide-imide resin, etc., and from the viewpoint of heat resistance and long-term reliability, silicone resin (polysiloxane) is particularly preferred. The polysiloxane as resin (A) can be appropriately selected from those that are conventionally known and commercially available and commonly used as various silicone materials. Therefore, those that are heat-curing type, room temperature curing type, or further UV curing type can be used, or those with a curing mechanism of condensation type or addition type, etc. Furthermore, the groups bonded to silicon atoms are not particularly limited. Examples include alkyl groups such as methyl, ethyl, and propyl; cycloalkyl groups such as cyclopentyl and cyclohexyl; alkenyl groups such as vinyl and allyl; and aryl groups such as phenyl and tolyl. Groups in which the hydrogen atoms are partially replaced by other atoms or bonding groups can also be cited. In this invention, the polyorganosiloxane as resin (A) may contain additives such as a crosslinking agent for crosslinking the polyorganosiloxane and a catalyst for promoting curing. For example, in this invention, the polyorganosiloxane as resin (A) is preferably a two-liquid addition-curing polyorganosiloxane resin (CY52-276A / B: manufactured by Dow Toray Co., Ltd.). In this two-liquid addition-curing polyorganosiloxane resin, the polyorganosiloxane having vinyl groups at both ends as the main polymer, the hydrogen-containing polyorganosiloxane as the crosslinking agent, and the platinum catalyst are separated into liquid A and liquid B. By mixing the two liquids in a specified ratio and heating the main polymer and crosslinking agent under the action of a platinum catalyst to carry out a crosslinking reaction, a two-liquid addition curable polyorganosiloxane resin can be formed into a cured product. Alternatively, the polyorganosiloxane as resin (A) can be, for example, a light (ultraviolet) curable polyorganosiloxane resin in which a polyorganosiloxane with vinyl groups at both ends is used as the main polymer and a polyorganosiloxane containing mercapto or mercaptoalkyl groups is used as the crosslinking agent, and a moisture-curable polyorganosiloxane resin is crosslinked through a condensation reaction with water. Furthermore, when it is necessary to make the cured product flexible at low temperatures, it is preferable to use a substance obtained by modifying at least a portion of the polyorganosiloxane of the main polymer with phenyl groups.

[0020] From the viewpoint of the relationship between the content of the thermally conductive filler (B) described later and the curing of the composition to form a high-dielectric thermally conductive component with good thermal conductivity, flexibility, etc., the content of resin (A) in the high-dielectric thermally conductive composition of the present invention is preferably 12% to 50% by volume, more preferably 15% to 40% by volume, and even more preferably 20% to 35% by volume relative to the total volume of the composition.

[0021] (Thermal conductive filler (B)) Next, the thermally conductive filler (B) will be described. The thermally conductive filler (B) constituting the high dielectric thermally conductive composition of the present invention includes at least a first thermally conductive filler (b1). In addition, the thermally conductive filler (B) may also include a second thermally conductive filler (b2). In this way, by including the first thermally conductive filler (b1) and the second thermally conductive filler (b2), the thermal conductivity, dielectric properties, flexibility, and electrical insulation of the cured product of the high dielectric thermally conductive composition of the present invention can be adjusted.

[0022] The thermally conductive filler (B) in the high-dielectric thermally conductive composition of the present invention is contained in an amount of 50 vol% to 88 vol% relative to the total composition. Thus, by containing the thermally conductive filler (B) in the high-dielectric thermally conductive composition, the cured product of the high-dielectric thermally conductive composition of the present invention can achieve moderate flexibility (moderate Asker C) and high electrical insulation (high volume resistivity) while possessing high thermal conductivity (higher thermal conductivity value), high dielectric properties (higher relative permittivity value, lower dielectric loss tangent value). From the viewpoint of ensuring such physical properties, the content of the thermally conductive filler (B) is 50 vol% to 88 vol% of the total high-dielectric thermally conductive composition, preferably 60 vol% to 85 vol%, and particularly more preferably 65 vol% to 80 vol%. In this invention, the volume of each filler contained in the thermally conductive filler (B) can be determined according to, for example, the gas displacement method of JIS Z8807:2012, and the contents of the thermally conductive filler (B), the first thermally conductive filler (b1), and the second thermally conductive filler (b2) can be calculated and determined from this value and the overall volume of the composition.

[0023] (First thermally conductive filler (b1)) Next, the first thermally conductive filler (b1) constituting the thermally conductive filler (B) will be described. The first thermally conductive filler (b1) is a component used to impart not only thermal conductivity but also high dielectric properties to the cured product of the high dielectric thermally conductive composition. Importantly, in this invention, the first thermally conductive filler (b1) has a volume resistivity of 1.0 × 10⁻⁶ Ω·cm to 1.0 × 10⁻⁶ Ω·cm. 8 The physical properties in Ω·cm are further optimized to have a volume resistivity of 1.0 × 10⁻⁶. 2 Ω·cm~1.0×108 Ω·cm. Therefore, as the first thermally conductive filler (b1), there are no particular limitations on the filler having such a volume resistivity. For example, inorganic fillers such as metals, metal oxides, metal hydroxides, metal nitrides, metal salts, carbides, and ferrites, and organic fillers such as polymer particles, which are known fillers that can be filled into the resin, can be used. More specifically, examples of first thermally conductive fillers (b1) include silicon carbide (SiC), metallic silicon (Si), zinc oxide (ZnO), and magnetite. However, from the viewpoint of obtaining a cured product with high thermal conductivity and high dielectric properties, silicon carbide (SiC) and metallic silicon (Si) are particularly preferred. By using a filler having the volume resistivity specified above, the cured product of the high dielectric thermal conductivity composition of the present invention possesses high thermal conductivity (high thermal conductivity value), high dielectric properties (high relative permittivity value, low dielectric loss tangent value), moderate flexibility (moderate Asker C), and high electrical insulation (high volume resistivity value). The first thermally conductive filler (b1) can be a mixture of two or more of the aforementioned different filler materials. Furthermore, the particle shape of the first thermally conductive filler (b1) is not particularly limited, and can be appropriately selected from spherical, flat, amorphous, needle-like, fibrous, etc., considering the filling properties of the high dielectric thermal conductivity composition. Additionally, when the first thermally conductive filler (b1) is a crystalline filler, it can be applied to both monocrystalline and polycrystalline materials.

[0024] Here, the particle size of the first thermally conductive filler (b1) can be selected appropriately; for example, the average particle size D of the first thermally conductive filler (b1) can be chosen. 50 The particle size can range from 0.1 μm to 100 μm. Here, from the viewpoint of further improving the relative permittivity of the cured product (thermal conductive component) of the high dielectric thermal conductivity composition of the present invention, the average particle size D of the first thermally conductive filler (b1) is... 50 Preferably, the particle size is 3μm to 50μm. Furthermore, from the viewpoint of simultaneously improving the volume resistivity of the cured material (thermal conductive component), the average particle size D of the first thermally conductive filler (b1) is particularly preferred. 50 The particle size ranges from 10 μm to 40 μm. In addition, to improve the filling properties of the resin (A), the first thermally conductive filler (b1) can also be combined with fillers of different particle sizes.

[0025] The content of the first thermally conductive filler (b1) in the high-dielectric thermally conductive composition of the present invention is 7% to 35% by volume relative to the total composition. By setting it in this way, the cured product of the high-dielectric thermally conductive composition of the present invention can achieve moderate flexibility and high electrical insulation while possessing high thermal conductivity and high dielectric properties. From the viewpoint of further improving these properties, the content of the first thermally conductive filler (b1) is 10% to 30% by volume, more preferably 15% to 20% by volume, of the total high-dielectric thermally conductive composition.

[0026] (Second thermally conductive filler (b2)) Next, the second thermally conductive filler (b2) will be described. The thermally conductive filler (B) constituting the high dielectric thermally conductive composition of the present invention contains the second thermally conductive filler (b2). The second thermally conductive filler (b2) is a component used to impart high thermal conductivity and high electrical insulation to the cured product of the high dielectric thermally conductive composition. In the present invention, the second thermally conductive filler (b2) has a volume resistivity exceeding 1.0 × 10⁻⁶. 8 The physical property is Ω·cm. Therefore, as the second thermally conductive filler (b2), there is no particular limitation as long as the filler has such a volume resistivity. For example, known fillers that can be filled into the resin can be used, such as inorganic fillers such as metals, metal oxides, metal hydroxides, metal nitrides, metal salts, carbides, and ferrites, and organic fillers such as polymer particles. More specifically, examples of the second thermally conductive filler (b2) include alumina, aluminum nitride, boron nitride, zinc oxide, silicon nitride, diamond, aluminum hydroxide, magnesium oxide, titanium oxide, silicon oxide, mica, soda glass, borosilicate glass, acrylic particles, styrene particles, melamine particles, polyethylene particles, and polyimide particles. In this invention, alumina, aluminum nitride, boron nitride, silicon nitride, diamond, aluminum hydroxide, and magnesium oxide are particularly preferred as the second thermally conductive filler (b2). Cured products of the high dielectric and thermally conductive compositions of the present invention containing these components can achieve moderate flexibility and high electrical insulation while possessing high thermal conductivity and high dielectric properties. The second thermally conductive filler (b2) described above can also be a mixture of two or more of the filler materials with different compositions described above.

[0027] The particle size of the second thermally conductive filler (b2) can be selected appropriately, but from the viewpoint of improving the filling rate in the high dielectric thermally conductive composition of the present invention, it is preferable to combine fillers with different particle sizes, such as large-particle-size components, medium-particle-size components, and small-particle-size components. For example, it is preferable to use the average particle size D of the large-particle-size component. 50 The average particle size D of the medium-sized component is 20μm to 100μm. 50 The average particle size D of the small-particle-size components is 1μm to 20μm. 50The filler material is 0.01μm to 1μm.

[0028] In this invention, the content of the second thermally conductive filler (b2) relative to the total composition is not particularly limited. However, from the viewpoint of improving the electrical insulation of the cured product of the high dielectric thermally conductive composition of this invention, it is preferable to contain more of the second thermally conductive filler (b2) than the first thermally conductive filler (b1). In the second thermally conductive filler (b2), the mixing ratio of large-particle-size components, medium-particle-size components, and small-particle-size components can be appropriately set. However, since the more large-particle-size components there are and the higher the filling rate, the higher the thermal conductivity of the cured product of the composition of this invention, it is preferable to set it in a way that the large-particle-size components are more abundant and the filling rate is higher. Furthermore, based on the content and particle size (average particle size or particle size distribution) of the first thermally conductive filler (b1), the mixing ratio of large-particle-size components, medium-particle-size components, and small-particle-size components is set in a way that the filling rate of the thermally conductive filler (B) in the high dielectric thermally conductive composition is increased. In the high dielectric thermal conductivity composition of the present invention, the content of the second thermally conductive filler (b2) relative to the composition as a whole is preferably 40% to 80% by volume, more preferably 45% to 78% by volume. Thus, the cured product of the high dielectric thermal conductivity composition of the present invention can achieve moderate flexibility and high electrical insulation while possessing high thermal conductivity and high dielectric properties.

[0029] (Other ingredients) Without prejudice to the purpose of the present invention, the high dielectric thermal conductivity composition of the present invention may contain other components, such as dispersants that improve the dispersibility of the thermally conductive filler (B) in the high dielectric thermal conductivity composition components, reaction inhibitors for adjusting the curing speed, heat stabilizers, adhesive agents for adjusting adhesion, pigments / dyes for coloring, flame retardants, release agents for good demolding from the mold or release film, and various additives for imparting function.

[0030] For example, known substances such as silane coupling agents can be used as dispersants, but single-terminal hydrolyzable polyorganosiloxanes with hydrolyzable groups bonded to single-terminal silicon atoms are preferred. By using such a dispersant, even when a thermally conductive filler (B) is added at a high filler ratio to improve the mechanical strength of the cured product, the thermally conductive filler (B) can be well dispersed in the resin (A). Furthermore, specific examples of single-terminal hydrolyzable polyorganosiloxanes include polyorganosiloxanes containing single-terminal alkoxy groups, preferably polyorganosiloxanes containing single-terminal trimethoxy groups or polyorganosiloxanes containing single-terminal triethoxy groups. In addition, to maintain the flexibility of the cured product at low temperatures, the aforementioned single-terminal hydrolyzable polyorganosiloxanes can also be phenyl modified by introducing phenyl groups into the siloxane molecular chain.

[0031] In addition, heat stabilizers are components that impart heat resistance and plasma etching resistance to the cured product of a high dielectric thermal conductivity composition, while also reducing oil seepage. Specific examples of heat stabilizers include known substances such as iron oxide, carbon black, graphite, carbon nanotubes, carbon fibers, iron carboxylates, cesium hydrates, titanium dioxide, barium zirconate, cerium octoate and zirconium octoate, and porphyrins. Heat stabilizers of carbon-based materials that do not act as oxidants under reduced pressure and heating conditions and have excellent free radical scavenging properties are particularly preferred. Heat stabilizers can be used alone or in combination. When resin (A) is a polyorganosiloxane, the proportion of heat stabilizer relative to 100 parts by weight of resin (A) is 0.1 to 20 parts by weight, more preferably 5 to 15 parts by weight, and particularly preferably 5 to 10 parts by weight. When the proportion of heat stabilizer is less than 5 parts by weight, sufficient heat stabilization may not be achieved in the cured product of the high dielectric thermal conductivity composition. When it exceeds 20 parts by weight, reduced thermal conductivity and poor dispersion of the heat stabilizer may occur in the high dielectric thermal conductivity composition. It should be noted that when using a conductive carbon-based material as a heat stabilizer, a proportion that does not impair the electrical insulation or dielectric properties of the cured product of the high dielectric thermal conductivity composition is preferred.

[0032] (Preparation method of high dielectric and thermally conductive composition) The high dielectric and thermal conductivity composition of the present invention can be easily prepared by uniformly mixing the above-mentioned (A) and (B) and other various components added as needed in a prescribed ratio. The mixing method is not particularly limited, and a known mixer or kneader can be used. This high dielectric and thermal conductivity composition can be cured by allowing it to stand at room temperature or by heating or light irradiation to promote a cross-linking reaction.

[0033] (High dielectric thermal conductivity components) The high dielectric thermal conductivity component of the present invention is composed of a cured product obtained by curing the aforementioned high dielectric thermal conductivity composition. A cured product of the high dielectric thermal conductivity composition is obtained by molding the high dielectric thermal conductivity composition into a suitable shape such as a block or sheet and then placing it at room temperature or by heating or light irradiation to promote a crosslinking reaction. In molding the high dielectric thermal conductivity composition, known methods such as die molding or calendering can be used, for example. When the cured product of the high dielectric thermal conductivity composition is molded into a block, die molding is preferred. In particular, when the resin (A) is a thermoplastic resin, die molding of the high dielectric thermal conductivity composition is preferably performed by heat molding or injection molding; when the resin (A) is a thermosetting resin or a photocurable resin, casting molding, LIM molding, etc., are preferred. When the cured product of the high dielectric thermal conductivity composition is molded into a sheet, calendering is preferred.

[0034] As described above, the high dielectric thermal conductivity component of the present invention is obtained from the cured product of the high dielectric thermal conductivity composition. Since the resin (A) constituting the high dielectric thermal conductivity composition has excellent thermal stability, a polyorganosiloxane is preferred. This high dielectric thermal conductivity component has a relative permittivity of 8 or higher, a thermal conductivity of 1.0 W / m·K or higher, and a dielectric loss tangent (tanδ) of 0.01 or lower. The relative permittivity and dielectric loss tangent (tanδ) can be set within the above range according to the dielectric characteristics of the electrostatic chuck device and its surrounding parts in the semiconductor etching apparatus to which it is applied. Because such a high dielectric thermal conductivity component has a sufficiently small dielectric loss tangent (tanδ), it is difficult to generate heat even in semiconductor etching apparatuses that generate high-frequency electric fields, as described later, and is therefore suitable for use in such apparatuses. Furthermore, from the viewpoint of approximating the relative permittivity of other components used in semiconductor etching apparatuses, the relative permittivity of the high dielectric thermal conductivity component of the present invention is preferably 10 or higher, more preferably 10 to 20. Furthermore, from the viewpoint of effectively dissipating heat from the focusing ring by disposing the high-dielectric-thermal-conductivity component of the present invention between the stage and the focusing ring of the semiconductor etching apparatus that generates a high-frequency electric field, it is preferable that the high-dielectric-thermal-conductivity component has a higher thermal conductivity, specifically, more preferably 5.0 W / m·K or higher. Additionally, from the viewpoint of mounting the high-dielectric-thermal-conductivity component of the present invention in a semiconductor etching apparatus 100 that generates a high-frequency electric field, the electrical insulation property preferably has a volume resistivity of 1.0 × 10⁻⁶. 9 For a hardness of Ω·cm or higher, the preferred softness is Asker C5~75 (SRIS 0101 standard, 23±2℃), with Asker C15~65 being particularly preferred.

[0035] The shape of the high-dielectric thermally conductive component of the present invention is not particularly limited, and it can be appropriately molded into a block, sheet, etc., depending on the application. However, when it is disposed between adjacent components to improve the thermal conductivity between the components, it is preferable to be molded into a sheet. When the high-dielectric thermally conductive component is disposed between components to transfer heat between them, since the thickness direction of the sheet-shaped high-dielectric thermally conductive component is the main heat conduction direction, from the viewpoint of reducing thermal resistance, the thickness is preferably thin, specifically preferably 1 mm or less, more preferably 0.5 mm or less, and even more preferably 0.1 mm or less.

[0036] Furthermore, depending on the application or device shape, the surface shape of the high-dielectric thermally conductive component of the present invention can be appropriately set to a circle, rectangle, or irregular shape. When the high-dielectric thermally conductive component is in sheet form, after the uncured composition is supplied onto a substrate film, it can be formed into a sheet using known methods such as calendering and then cured. The cured sheet can then be molded into the desired shape using known methods such as punching, laser processing, or plotter processing.

[0037] Furthermore, the surface of the high-dielectric thermally conductive component of the present invention can be a smooth surface, but it is preferable to form minute irregularities. Typically, when a thermally conductive component is positioned between the stage and the focusing ring of a semiconductor etching apparatus, if air bubbles exist between the stage and the high-dielectric thermally conductive component, or between the focusing ring and the high-dielectric thermally conductive component, the thermal resistance increases, hindering heat transfer from the focusing ring to the stage. However, by forming minute irregularities on the surface of the high-dielectric thermally conductive component of the present invention that do not affect the degree of sealing, it becomes easy to eliminate such air bubbles. For example, the minute irregularities on the surface of the high-dielectric thermally conductive component preferably have a height difference of 10 μm to 100 μm between the highest point of the convex portion and the lowest point of the concave portion on the wafer surface, and the area occupied by the convex portion in the wafer surface area is 50% to 95%. The shape of the irregularity pattern can be appropriately set, but from the viewpoint of easily avoiding air bubble residue, a grid-like groove is preferred.

[0038] Furthermore, the surface of the high-dielectric thermally conductive component of the present invention can be non-adhesive or adhesive. From the viewpoint of ease of loading and unloading with the stage or focusing ring of the semiconductor etching apparatus, the surface of the high-dielectric thermally conductive component can also have different adhesive properties on the surface in contact with the stage and the surface in contact with the focusing ring. For the surface of the high-dielectric thermally conductive component, adhesiveness can be imparted by applying an adhesive silicone resin as resin (A). In addition, adhesiveness can also be imparted by known methods such as adding an adhesive agent to the high-dielectric thermally conductive composition of the present invention first, or applying an adhesive coating to the surface after curing the high-dielectric thermally conductive composition of the present invention. Alternatively, by using a non-adhesive silicone resin as resin (A), the surface of the high-dielectric thermally conductive component can be non-adhesive. In addition, the surface of the high-dielectric thermally conductive component can be non-adhesive by known methods such as applying a non-adhesive coating to the surface after curing the high-dielectric thermally conductive composition of the present invention, or performing surface modification methods such as excimer laser treatment or plasma treatment.

[0039] (Semiconductor etching device) Next, a semiconductor etching apparatus equipped with the high dielectric thermal conductivity component of the present invention will be described together with the high dielectric thermal conductivity component of the present invention. The high dielectric thermal conductivity component of the present invention is a high dielectric thermal conductivity component composed of a cured product of a high dielectric thermal conductivity composition, and is mounted on the semiconductor etching apparatus 100.

[0040] like Figure 1 As shown, the high dielectric thermal conductivity component 5 of the present invention is a component mounted on the substrate mounting unit 1 of the semiconductor etching apparatus 100. The substrate mounting unit 1 includes a mounting stage 2 (hereinafter also referred to as the lower electrode unit 2), a focusing ring 3 disposed on the outer periphery of the mounting stage 2, and a cooling unit 4; wherein the mounting stage 2 includes a chuck mechanism 2a for mounting the wafer W and fixing it by means of an electrostatic chuck or the like, and a support stage 2b that functions as the lower electrode. The high dielectric thermal conductivity component 5 of the present invention is disposed between the mounting stage 2 and the focusing ring 3. During the etching process, it is necessary to adjust the temperature of the wafer W to the optimal conditions, which is achieved by cooling the mounting stage 2 by the cooling unit 4 in a way that prevents the temperature of the wafer W from rising excessively due to plasma.

[0041] The semiconductor etching apparatus 100 performs etching on wafer W by placing it on substrate mounting unit 1 within a processing chamber and irradiating it with plasma. More specifically, the etching process for wafer W involves placing wafer W on mounting stage 2, maintaining a predetermined vacuum level within the processing chamber, fixing wafer W with a chuck mechanism 2a such as an electrostatic chuck, applying a high-frequency voltage between an upper electrode (not shown) and a lower electrode unit 2 positioned opposite to the lower electrode unit 2, generating plasma within the processing chamber, and etching the surface of wafer W. By arranging the focusing ring 3 around wafer W, the discontinuity of plasma in the peripheral region of wafer W can be mitigated, resulting in more uniform plasma treatment across the entire surface of wafer W.

[0042] As described above, the thermal conductivity of the high-dielectric thermal conductivity component of the present invention is 1.0 W / m·K or higher. During the etching process performed by the semiconductor etching apparatus 100, the focusing ring 3 is also irradiated by plasma and its temperature rises. The temperature of the peripheral edge of the wafer W is higher than that of the central region of the wafer W, which may deteriorate the etching characteristics. However, by placing the high-dielectric thermal conductivity component 5 of the present invention between the stage 2 and the focusing ring 3, heat is transferred from the focusing ring 3 to the stage 2 via the high-dielectric thermal conductivity component 5, thus preventing the focusing ring 3 from overheating. Furthermore, in the semiconductor etching apparatus 100, many components with high relative permittivity are used, primarily the chuck mechanism 2a. However, the relative permittivity of the high-dielectric thermal conductivity component 5 of the present invention is 8 or higher. Therefore, the difference in relative permittivity between the components within the semiconductor etching apparatus 100 is small, and an improvement in yield during etching operations can be expected. In addition, the dielectric loss tangent tanδ of the high dielectric thermal conductivity component 5 of the present invention is sufficiently small, less than 0.01, so the heat generation is not high even in environments that generate high frequency electric fields, making it suitable for use in semiconductor etching apparatus 100.

[0043] Example The present invention will be specifically described below through embodiments, but the present invention is not particularly limited to these embodiments.

[0044] The methods for determining the physical properties in the examples and comparative examples are as follows.

[0045] (1) Thermal conductivity For the evaluation of thermal conductivity, two 25mm × 25mm × 10mm thick block-shaped cured materials were prepared as a pair of samples. A Kapton 5465F1 sensor with a diameter of 3.189mm was used, and the thermal conductivity of the block-shaped cured materials was determined according to ISO 22007-2 using the hot plate method in block mode 1 of a thermophysical property measuring apparatus (Hot disk AB TPS2500S). For the evaluation of the thermal conductivity of the cured materials, those exceeding 5 W / m·K were considered exceptionally high quality (◎), those above 1 W / m·K and below 5 W / m·K were considered acceptable (○), and those below 1 W / m·K were considered unacceptable (×).

[0046] (2) Relative permittivity (dielectric properties) For dielectric evaluation, a 90mm × 90mm × 0.5mm thick sheet of cured material was prepared, and the relative permittivity of the sheet-like cured material was determined according to JIS C2138 using a dielectric property measuring apparatus (WAYNE KERR PRECISION COMPONENT ANALYZER 6440B). For the evaluation of the relative permittivity of the cured material, a value of 10 or higher was considered exceptionally high quality (◎), 8 or higher but less than 10 was considered acceptable (○), and less than 8 was considered unacceptable (×).

[0047] (3) Dielectric loss tangent (dielectric properties) A sheet of cured material with a thickness of 90mm × 90mm × 0.5mm was prepared. The dielectric loss tangent of the sheet-like cured material was measured using a dielectric property testing device (WAYNE KERR PRECISION COMPONENT ANALYZER 6440B) according to JIS C2138. For the evaluation of the dielectric loss tangent of the cured material, a tangent below 0.01 was considered acceptable (◎), and a tangent exceeding 0.01 was considered unacceptable (×).

[0048] (4) Volume resistivity (electrical insulation) A 50mm × 50mm × 0.5mm thick sheet-like cured material was prepared, and its volume resistivity was measured according to JIS K6911 using a volume resistivity measuring apparatus (Nittoseiko Analytech Co., Ltd. Highresta UP MCP-HT450). For evaluating the electrical insulation properties of the cured material, a volume resistivity of 1.0 × 10⁻⁶ was used. 11 Ω·cm or higher is considered exceptionally high quality (◎), and 1.0×10 10 Ω·cm or higher and less than 1.0×10 11 Ω·cm is considered acceptable (○), 1.0×10 10 Ω·cm is considered unqualified (×).

[0049] (5) Hardness (Asker C) (Softness) A 50mm × 50mm × 10mm thick block of cured material was prepared. The hardness (Asker C) of the sheet-like cured material was measured using a hardness tester (Asker rubber hardness tester Type C manufactured by KOBUNSHI KEIKI CO.,LTD.) according to JIS K7312. For the evaluation of the softness of the cured material, a hardness (Asker C) of 15 to 65 was considered exceptionally high quality (◎), a hardness exceeding 65 but below 75, or less than 15, was considered acceptable (○), and a hardness exceeding 75 was considered unacceptable (×).

[0050] The names and properties of the components of the raw materials used in the following examples and comparative examples are shown below.

[0051] (Resin (A)) Resin (A) is a thermosetting polysiloxane with a two-component addition process (manufactured by Dow Toray Co., Ltd., DOWSIL CY52-276).

[0052] Thermally conductive filler (B) The materials shown in Table 1 are used as the first thermally conductive filler (b1).

[0053] [Table 1]

[0054] As the second thermally conductive filler (b2), the material obtained by mixing the materials shown in Table 2 with the proportions shown in Table 3 is used.

[0055] [Table 2]

[0056] [Table 3]

[0057] (Sample preparation) The compositions of the examples and comparative examples were prepared according to the following steps, and their respective cured products were produced.

[0058] The materials of the first thermally conductive filler (b1) shown in Table 1 and the second thermally conductive filler (b2) shown in Table 3 were added to resin (A). The mixture was then mixed for 2 minutes using a benchtop mixer (THINKY Co., Ltd., Awatori Rentaro) and subjected to vacuum degassing for 5 minutes to obtain an uncured composition. Compositions obtained by varying the proportions of the first thermally conductive filler (b1) and the second thermally conductive filler (b2) relative to 100g of resin (A) were used as the high dielectric thermally conductive compositions of Examples 1-18 and the compositions of Comparative Examples 1-5, respectively. The proportions of each component in Examples 1-18 and Comparative Examples 1-5 are shown in Tables 4-7. It should be noted that the contents (volume%) of the first thermally conductive filler (b1) and the second thermally conductive filler (b2) shown in Tables 4 to 7 were determined by measuring the volume of each filler relative to the volume of the whole composition after mixing, according to the gas displacement method of JIS Z8807:2012 for each filler, before mixing with resin (A).

[0059] Next, for the high dielectric thermal conductivity compositions of Examples 1 to 18 and the compositions of Comparative Examples 1 to 5, respectively, they were cast in molds, preheated at 70°C for 1 hour in an atmospheric atmosphere in a hot air oven (Tokyo Rikka Kikaku Co., Ltd. WFO-520W) and then heated at 100°C for 3 hours to solidify them, so as to obtain the above-mentioned (1) thermal conductivity and (5) hardness evaluation samples.

[0060] Next, the high dielectric thermal conductivity compositions of Examples 1 to 18 and the compositions of Comparative Examples 1 to 5 were sandwiched between a pair of PET films, calendered to a specified thickness, and then preheated at 70°C for 1 hour in an atmospheric atmosphere in a hot air oven (Tokyo Rikka Equipment Co., Ltd. WFO-520W) to cure them. They were then punched into a specified shape to obtain the above-mentioned (2) relative permittivity, (3) dielectric loss tangent, and (4) volume resistivity evaluation samples.

[0061] [Table 4]

[0062] [Table 5]

[0063] [Table 6]

[0064] [Table 7]

[0065] As shown in Table 5, it is clear from the results of Comparative Example 1 that when the thermally conductive filler (B) included at least 40% by volume relative to the total composition (at least along with the resin (A) constituting the composition) has a thermal conductivity as low as 0.9, it does not have sufficient thermal conductivity. In addition, the volume resistivity is as low as 8.946 × 10⁻⁶. 4 The conductivity is too high (Ω·cm), making it unsuitable for high-frequency applications such as semiconductor etching apparatuses. The results of Comparative Example 3 clearly show that when the thermally conductive filler (B) included at least 90% by volume relative to the total composition (A) is present, the Asker C is as high as 88.2, resulting in insufficient flexibility and strength, making it unsuitable for semiconductor etching apparatuses. In contrast, as shown in Tables 4 to 7, the results of Examples 1 to 18 (especially Examples 2, 7, and 8) clearly show that in the high-dielectric thermally conductive composition of the present invention, at least 50% to 85% by volume relative to the total composition is included. Therefore, the cured high-dielectric thermally conductive composition of the present invention possesses high dielectric properties (relative dielectric constant of 8 or higher, dielectric loss tangent of 0.01 or lower) and moderate flexibility (Asker C of 5 to 75), while also exhibiting high thermal conductivity (thermal conductivity of 1 W / m·K or higher) and a volume resistivity of 1.0 × 10⁻⁶ for electrical insulation. 10 With a strength of Ω·cm or higher, it is suitable for use in semiconductor etching equipment, etc.

[0066] Furthermore, as shown in Table 6, the results of Comparative Example 5 indicate that the first thermally conductive filler (b1) constituting the thermally conductive filler (B) has a volume resistivity of 1.0 × 10⁻⁶. 14 When the alumina content is Ω·cm, the relative permittivity of the sheet sample is less than 8, resulting in a large difference in relative permittivity compared to other components typically mounted in semiconductor etching equipment. Furthermore, the results of Comparative Example 4 show that the first thermally conductive filler (b1) has a volume resistivity of 1.0 × 10⁻⁶. -2 When the carbon fiber has a dielectric loss tangent (tanδ) of Ω·cm, the sheet-like sample exhibits a dielectric loss tangent exceeding 0.01, thus easily generating heat. Furthermore, the volume resistivity of the sheet-like sample is less than 1.0 × 10⁻⁶. 10 The volume resistivity is Ω·cm, therefore its electrical insulation is insufficient, making it unsuitable for use in semiconductor etching devices, etc. In contrast, as shown in Tables 4 to 7, the first thermally conductive filler (b1) constituting the thermally conductive filler (B) in Examples 1 to 8 and Examples 10 to 18 has a volume resistivity of 0.53 × 10⁻⁶ Ω·cm. 6 The first thermally conductive filler (b1) constituting the thermally conductive filler (B) in Example 9 has a volume resistivity of 1.4 × 10⁻⁶ Ω·cm. 1Metallic silicon (Si) with a dielectric loss tangent of Ω·cm has a small dielectric loss tangent (tanδ) that makes it less prone to heating, and also has a high volume resistivity and excellent electrical insulation. The results from Examples 1-18 show that the volume resistivity through at least the first thermally conductive filler (b1) is 1.4 × 10⁻⁶. 1 Ω·cm or higher, 0.53×10 6 The dielectric loss tangent tanδ of the cured high dielectric thermal conductivity composition of the present invention is 0.01 or less, and the volume resistivity is 1.0 × 10⁻⁶ Ω·cm or less. 10 With a relative permittivity of Ω·cm or higher and a relative permittivity of 8 or higher, the difference in relative permittivity between this material and that of components mounted in semiconductor etching apparatuses is small, resulting in a high-dielectric-conductivity thermally conductive component suitable for high-frequency applications such as semiconductor etching apparatuses. Furthermore, as shown in Table 6, the results from Examples 5 and 9 and Comparative Examples 4 and 5 indicate that silicon carbide (SiC) and metallic silicon (metallic Si) are preferred as the first thermally conductive filler (b1) constituting the thermally conductive filler (B).

[0067] As shown in Table 7, the high dielectric thermally conductive compositions of the present invention in Examples 10-16, except for the first thermally conductive filler (b1), have different average particle sizes D of 0.5 μm or more and 58.6 μm or less, respectively. 50 Apart from that, they have the same composition. Since the cured products of the high dielectric thermally conductive compositions of the present invention in Examples 10-16 all passed the above-described physical property evaluation, it can be concluded that the high dielectric thermally conductive composition of the present invention preferably has an average particle size D of the first thermally conductive filler (b1). 50 It is at least 0.5μm and above, and less than 58.6μm.

[0068] In addition, the average particle size D of the first thermally conductive filler (b1) was found to be... 50 The larger the particle size, the lower the volume resistivity of the cured high dielectric thermal conductivity composition of the present invention tends to be. The average particle size D of the first thermally conductive filler (b1) 50 In Example 16, with a thickness of 58.6 μm, the volume resistivity of the cured material was 0.99 × 10⁻⁶. 11 Ω·cm, although acceptable, is a low value; in contrast, the average particle size D of the first thermally conductive filler (b1) is... 50 In Example 15, with a thickness of 49.4 μm, the volume resistivity of the cured material was 1.18 × 10⁻⁶. 11 Ω·cm, indicating high quality. Furthermore, in Examples 10-16, the average particle size D of the first thermally conductive filler (b1) is... 50 The highest relative permittivity was observed in the cured material of Example 13 with a particle size of 30.9 μm, and it decreased with increasing average particle size D. 50 When the diameter deviates from 30.9 μm, the relative permittivity of the cured material tends to decrease.

[0069] Furthermore, based on the results of Examples 1 to 18, it can be confirmed that the high dielectric thermal conductivity composition of the present invention can contain 40 vol% to 75 vol% of a volume resistivity of 1 × 10⁻⁶. 8 A second thermally conductive filler (b2) with a conductivity of Ω·cm or higher.

[0070] Furthermore, the high dielectric thermal conductivity compositions of the present invention in Examples 17 and 18 differ from those in Example 13 only in the composition of the second thermal conductivity filler (b2), while the content of the second thermal conductivity filler (b2) relative to the overall composition is the same. Since the above-described physical property evaluations of the cured products of the high dielectric thermal conductivity compositions of the present invention in Examples 17 and 18 are satisfactory, it can be confirmed that the second thermal conductivity filler (b2), in addition to alumina, can at least be aluminum nitride (AlN) or magnesium oxide (MgO).

[0071] This invention is not limited to the above-described embodiments or examples, and various design changes that do not depart from the spirit of the invention as set forth in the claims are also included within the scope of the invention.

[0072] [Industry availability] The high dielectric and thermally conductive composition of the present invention has electrical insulation and moderate flexibility, while also having high thermal conductivity and high dielectric properties, and is therefore useful as a material for components of devices utilizing high-frequency currents, and is widely used in industries such as electronic devices and semiconductor devices.

[0073] [Symbol Explanation] 1. Substrate mounting unit 2. Mounting stage (lower electrode unit) 2a Chuck mechanism (wafer chuck, etc.) 2b Support platform 3. Focusing ring (edge ​​ring) 4 Cooling Unit 5. Thermal conductive components W is the substrate (wafer, etc.) being processed. 100 Semiconductor Etching Equipment

Claims

1. A high dielectric and thermally conductive composition, characterized in that, It comprises a resin (A) and a thermally conductive filler (B), wherein the content of the thermally conductive filler (B) is 50-88% by volume of the total composition, and the thermally conductive filler (B) has a volume resistivity of 1.0 × 10⁻⁶ to 1.0 × 10⁻⁶. 8 The first thermally conductive filler (b1) has an Ω·cm content of 7 to 35% of the total volume of the composition.

2. A high dielectric and thermally conductive component, characterized in that: It is composed of a cured product of the high dielectric and thermally conductive composition as described in claim 1. The high dielectric and thermally conductive component is disposed between the edge ring and the outer periphery of the electrostatic chuck, wherein the edge ring is disposed on the outer periphery of the substrate to be processed in the semiconductor etching apparatus, and the electrostatic chuck holds the substrate to be processed. The high dielectric and thermally conductive component has a relative permittivity of 8 or higher, a thermal conductivity of 1.0 W / m·K or higher, and a dielectric loss tangent tanδ of 0.01 or lower. The resin (A) is a polyorganosiloxane.

3. The high dielectric and thermally conductive component according to claim 2, characterized in that, The average particle size D of the first thermally conductive filler (b1) 50 The range is 0.1–100 μm.

4. The high dielectric thermal conductivity component according to claim 2 or 3, characterized in that, The average particle size D of the first thermally conductive filler (b1) 50 The size ranges from 10 to 40 μm.

5. The high dielectric and thermally conductive component according to any one of claims 2 to 4, characterized in that, The first thermally conductive filler (b1) is composed of at least one material selected from the group consisting of metallic silicon and silicon carbide.

6. The high dielectric and thermally conductive component according to any one of claims 2 to 5, characterized in that, The thermally conductive filler (B) also contains materials with a volume resistivity exceeding 1.0 × 10⁻⁶. 8 The second thermally conductive filler (b2) has an Ω·cm content of 40 to 80% of the total volume of the composition.

7. The high dielectric and thermally conductive component according to claim 6, characterized in that, The second thermally conductive filler (b2) is composed of at least one material selected from the group consisting of alumina, aluminum nitride, boron nitride, silicon nitride, diamond, aluminum hydroxide and magnesium oxide.

8. The high dielectric and thermally conductive component according to any one of claims 2 to 7, characterized in that, The volume resistivity is 1.0 × 10⁻⁶. 9 Ω·cm or higher.

9. The high dielectric and thermally conductive component according to any one of claims 2 to 8, characterized in that, The hardness is Asker C5~75 (SRIS 0101 standard, 23±2℃).

10. A semiconductor etching apparatus, characterized in that, The assembly includes the high dielectric thermal conductivity component as described in any one of claims 2 to 9.

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