Temperature adjustment member and electrostatic chuck device

Abstract

A temperature adjustment member that supports an electrostatic chuck member, in which at least a part includes an inner peripheral portion and an outer peripheral portion that differ from each other in thermal conductivity, the inner peripheral portion is formed of a first electrically conductive ceramic that contains a first high-thermal-conductivity material and a first electrically conductive material, the outer peripheral portion is formed of a second electrically conductive ceramic that contains a second high-thermal-conductivity material and a second electrically conductive material, and surrounds the outside of the inner peripheral portion in a closed loop shape in plan view, and the thermal conductivity of the outer peripheral portion is higher than that of the inner peripheral portion.

Description

Technical Field

[0001] This invention relates to a temperature adjustment component and an electrostatic chuck device.

[0002] This application asserts its priority based on Japanese Patent Application No. 2024-054289 filed in Japan on March 28, 2024, the contents of which are incorporated herein by reference. Background Technology

[0003] Conventionally, in semiconductor manufacturing processes such as IC, LSI, and VLSI production, electrostatic chuck devices are used to electrostatically adsorb plate-shaped samples, such as silicon wafers, during plasma treatment. These electrostatic chuck devices include a temperature adjustment component to control the temperature of the plate-shaped sample. The temperature adjustment component is a base that supports the electrostatic chuck component having electrodes for electrostatic adsorption, and also functions to dissipate heat from the plate-shaped sample placed on the electrostatic chuck component (for example, see Patent Document 1).

[0004] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2024-022214 Summary of the Invention The technical problem to be solved by the invention The electrostatic chuck device has a structure that differs between the center and periphery of the mounting surface, resulting in different contact states with the plate-shaped sample at these locations. Due to this difference in contact state, the periphery of the mounting surface containing the plate-shaped sample experiences poor heat dissipation during plasma treatment and is easily heated by the plasma, reaching high temperatures. Therefore, the periphery of the plate-shaped sample is more prone to temperature increases during plasma treatment compared to the center. When plasma treatment is performed under these different temperature conditions of the plate-shaped sample, the plasma treatment becomes uneven between the center and periphery, thus requiring improvement.

[0005] The present invention was made in view of this situation, and its object is to provide a temperature adjustment component capable of appropriately adjusting the temperature of the periphery of a plate-shaped sample placed in an electrostatic chuck device. Furthermore, its object is also to provide an electrostatic chuck device having such a temperature adjustment component and capable of appropriately adjusting the temperature of the periphery of a plate-shaped sample.

[0006] means for solving technical problems To address the aforementioned issues, the present invention provides a temperature adjustment component that supports an electrostatic chuck component. The temperature adjustment component includes: an inner peripheral portion formed of a first conductive ceramic comprising a first high thermal conductivity material and a first conductive material; and an outer peripheral portion formed of a second conductive ceramic comprising a second high thermal conductivity material and a second conductive material, and, when viewed from above, surrounds the outer side of the inner peripheral portion in a closed loop shape, wherein the thermal conductivity of the outer peripheral portion is higher than that of the inner peripheral portion.

[0007] More specifically, it includes the following methods.

[0008] [1] A temperature adjustment component that supports an electrostatic chuck component, wherein the temperature adjustment component comprises... At least a portion of the interior and exterior surfaces have different thermal conductivity. The inner circumference is formed of a first conductive ceramic comprising a first high thermal conductivity material and a first conductive material. The outer periphery is formed of a second conductive ceramic comprising a second high thermal conductivity material and a second conductive material, and when viewed from above, it surrounds the outer side of the inner periphery in a closed loop. The thermal conductivity of the outer periphery is higher than that of the inner periphery.

[0009] [2] The temperature adjustment component according to [1] has the following features: The intermediate portion, when viewed from above, is disposed between the inner peripheral portion and the outer peripheral portion, and is in contact with both the inner peripheral portion and the outer peripheral portion. The intermediate portion is formed of a third conductive ceramic, which includes the first high thermal conductivity material and the second high thermal conductivity material, as well as the first conductive material and the second conductive material. The thermal conductivity of the intermediate portion is higher than that of the inner peripheral portion and lower than that of the outer peripheral portion.

[0010] [3] According to the temperature adjustment component described in [1] or [2], wherein, The top view area of ​​the inner periphery is more than 55% and less than 95% of the top view area of ​​the temperature adjustment component.

[0011] [4] The temperature adjustment component according to any one of [1] to [3], wherein, The difference between the thermal conductivity of the inner circumference and the thermal conductivity of the outer circumference is more than 15 W / m·K and less than 250 W / m·K.

[0012] [5] The temperature adjustment component according to any one of [1] to [4], wherein, The difference between the coefficient of thermal expansion of the inner circumference and the coefficient of thermal expansion of the outer circumference is less than 2 ppm / K.

[0013] [6] An electrostatic chuck device, comprising: The temperature adjustment component as described in any one of [1] to [5]; and The electrostatic chuck component has a dielectric substrate and electrodes for electrostatic adsorption, and is supported by the temperature adjustment component. The electrostatic chuck component overlaps with the outer periphery when viewed from above.

[0014] [7] The temperature adjustment component according to any one of [1] to [5], wherein, The temperature adjustment component is formed only by the inner peripheral portion and the outer peripheral portion.

[0015] [8] The temperature adjustment component according to any one of [1] to [5], wherein, The temperature adjustment component is formed only by the inner peripheral portion, the middle portion, and the outer peripheral portion.

[0016] Invention Effects According to the present invention, a temperature adjustment component is provided that can appropriately adjust the temperature at the periphery of a plate-shaped sample in an electrostatic chuck device. Furthermore, the object is to provide an electrostatic chuck device having such a temperature adjustment component and capable of appropriately adjusting the temperature at the periphery of a plate-shaped sample. Attached Figure Description

[0017] Figure 1 This is a cross-sectional schematic diagram showing an example of the electrostatic chuck device 1 of this embodiment.

[0018] Figure 2 This is a schematic perspective view showing an example of an electrostatic chuck device 1.

[0019] Figure 3 This is a schematic diagram illustrating an example of the manufacturing method of base 3.

[0020] Figure 4 This is a schematic diagram illustrating an example of the manufacturing method of base 3.

[0021] Figure 5 This is a schematic diagram illustrating an example of the manufacturing method of base 3.

[0022] Figure 6 This is a schematic diagram illustrating an example of the manufacturing method of base 3.

[0023] Figure 7 This is a schematic diagram illustrating an example of the manufacturing method of base 3.

[0024] Figure 8 This is a schematic plan view showing a modified example of a conductive ceramic plate and base.

[0025] Figure 9 This is a schematic plan view showing a modified example of a conductive ceramic plate and base. Detailed Implementation

[0026] The following is for reference. Figures 1-9 A preferred embodiment of the temperature adjustment component and the electrostatic chuck device of this embodiment will be described. Furthermore, in all the following drawings, the dimensions or ratios of the constituent elements are appropriately varied for ease of observation. The following description is a detailed explanation for better understanding the spirit of the invention and does not limit the invention unless otherwise specified. For example, unless otherwise specifically limited, conditions such as materials, quantities, types, quantities, dimensions, shapes, positions, and ratios can be changed, added, or omitted as needed.

[0027] Temperature control components and electrostatic chuck devices Figure 1 This is a cross-sectional schematic diagram showing an example of the electrostatic chuck device 1 according to this embodiment. The electrostatic chuck device 1 includes an electrostatic chuck component 2, a base 3, and a bonding layer 4. The electrostatic chuck component 2 and the base 3 are stacked on top of each other via the bonding layer 4. The base 3 corresponds to the temperature adjustment component in this invention.

[0028] In this specification, the direction in which the electrostatic chuck component 2 and the base 3 are stacked is referred to as the stacking direction. Furthermore, the side on which the electrostatic chuck component 2 is disposed relative to the base 3 is sometimes referred to as "one side of the stacking direction," and its opposite side, i.e., the side on the base 3 on which the electrostatic chuck component 2 is not disposed, is referred to as "the other side of the stacking direction." In the following description, the vertical direction is used as the stacking direction to describe each part of the electrostatic chuck device 1. However, the vertical direction here is used only for simplification and is not intended to limit the orientation of the electrostatic chuck device 1 during use. Additionally, the upper side corresponds to one side of the stacking direction, and the lower side corresponds to the other side of the stacking direction.

[0029] <Electrostatic Chuck Components> The electrostatic chuck component 2 has a dielectric substrate 11 and an adsorption electrode 13 located inside the dielectric substrate 11. The electrostatic chuck component 2 has a first adsorption part 21 that adsorbs and holds the wafer W on its upper surface, and a second adsorption part 22 that adsorbs and holds the focusing ring FR on its upper surface.

[0030] The first adsorption part 21 is cylindrical, and a plurality of upwardly protruding protrusions 211 are provided on its upper surface. Furthermore, a closed-loop annular protrusion 212 is provided along the edge of the upper surface of the first adsorption part 21 at its periphery. In this specification, "top view" refers to the field of view observed from the thickness direction of the electrostatic chuck component 2.

[0031] The electrostatic chuck device 1 supports the wafer W at the top ends (upper surfaces) of a plurality of protrusions 211 and on the upper surface of annular protrusions 212. That is, in the electrostatic chuck device 1, the imaginary surface formed by connecting the upper surface of annular protrusions 212 and the upper surfaces of a plurality of protrusions 211 corresponds to the mounting surface 21a of wafer W.

[0032] When the wafer W is placed on the mounting surface 21a, the space surrounded by the lower surface of the wafer W, the plurality of protrusions 211, and the annular protrusions 212 functions as a flow path 21x for the flow of cooling gas. An electrostatic chuck device 1 is provided with a gas supply hole (not shown) extending through the electrostatic chuck device 1 in the thickness direction, and cooling gas is supplied to the flow path 21x from the gas supply hole. The cooling gas flowing in the flow path 21x cools the wafer W, which is heated during plasma processing.

[0033] The radius of the second adsorption portion 22 is larger than that of the first adsorption portion 21, and the second adsorption portion 22 is cylindrical and concentric with the first adsorption portion 21, and is integrally formed with the first adsorption portion 21. Specifically, the first adsorption portion 21 is formed in the center of the second adsorption portion 22. The upper surface 22a of the second adsorption portion 22 is exposed when viewed from above, surrounding the first adsorption portion 21. The upper surface 22a corresponds to the mounting surface for adsorbing and holding the focusing ring FR.

[0034] A groove 22x, which appears annular when viewed from above, is formed on the upper surface 22a. When the focusing ring FR is placed on the upper surface 22a, the space surrounded by the lower surface of the focusing ring FR and the groove 22x functions as a flow path for cooling gas. A gas supply hole (not shown) penetrating the electrostatic chuck device 1 in the thickness direction is provided, and cooling gas is supplied from the gas supply hole to the flow path (groove 22x). The cooling gas flowing in the flow path cools the focusing ring FR, which is heated during plasma processing.

[0035] (Dielectric substrate) The dielectric substrate 11 of the electrostatic chuck component 2 is formed of ceramic, which contains insulating and conductive materials, has sufficient mechanical strength, and is durable against corrosive gases and their plasmas.

[0036] The ceramic constituting the dielectric substrate 11 comprises aluminum oxide (Al2O3) or aluminum nitride (AlN) as an insulating material as a main component. "Main component" refers to a component comprising 50% or more of the total volume. The amount of the insulating material may be 60% or more, 70% or more, 80% or more, or 90% or more, depending on the requirements.

[0037] As a conductive material, there are no particular limitations as long as it is a material that can be used in the dielectric substrate 11. For example, at least one material selected from the group consisting of SiC, TiO2, TiN, TiC, W, WC, MoC, Mo2C, TaC, TaN, NbC, VC and C can be used.

[0038] The ceramic constituting the dielectric substrate 11 may appropriately be an alumina (Al2O3)-silicon carbide (SiC) composite sintered body. In particular, from the viewpoint of dielectric properties at high temperatures, high corrosion resistance, plasma resistance, and heat resistance, the material constituting the dielectric substrate 11 is preferably an Al2O3-SiC composite sintered body.

[0039] (Adsorption electrode) Adsorption electrodes 13 are disposed inside the dielectric substrate 11. Adsorption electrodes 13 extend along the mounting surface 21a of the dielectric substrate 11. Adsorption electrodes 13 generate an electrostatic adsorption force that holds the wafer W on the mounting surface 21a by applying a voltage. The shape or number of adsorption electrodes 13 in top view can be arbitrarily selected.

[0040] The adsorption electrode 15 is disposed inside the dielectric substrate 11. When viewed from above, the adsorption electrode 15 extends in a ring shape along the upper surface 22a of the second adsorption portion 22. The adsorption electrode 15 generates an electrostatic adsorption force that holds the wafer W on the upper surface 22a by applying a voltage.

[0041] Adsorption electrode 13 and adsorption electrode 15 are respectively connected to a power supply terminal (not shown) for applying DC voltage to adsorption electrode 13 and adsorption electrode 15.

[0042] Adsorption electrodes 13 and 15 are composed of a composite of insulating and conductive materials.

[0043] The insulating material contained in the adsorption electrode 13 and the adsorption electrode 15 is not particularly limited, but is preferably selected from at least one of the group consisting of alumina (Al2O3), aluminum nitride (AlN), silicon nitride (Si3N4), yttrium (III) oxide (Y2O3), yttrium aluminum garnet (YAG) and SmAlO3.

[0044] The conductive material contained in the adsorption electrode 13 is not particularly limited, but is preferably selected from at least one of the following groups: molybdenum carbide (Mo2C), molybdenum (Mo), tungsten carbide (WC), tungsten (W), tantalum carbide (TaC), tantalum (Ta), silicon carbide (SiC), carbon black, carbon nanotubes and carbon nanofibers.

[0045] The thickness of the electrostatic chuck component 2 is preferably 0.5 mm or more and 5 mm or less. If the thickness of the electrostatic chuck component 2 is 0.5 mm or more, the withstand voltage of the electrostatic chuck component 2 becomes higher. Furthermore, if the thickness of the electrostatic chuck component 2 is 5 mm or less, the heat capacity of the electrostatic chuck component 2 becomes smaller, thus making it easier to uniformly maintain the temperature of the plate-shaped sample being processed during plasma treatment.

[0046] <Base (Temperature Adjustment Component)> The base (temperature adjustment component) 3 is a circular plate-shaped component when viewed from above, supporting the electrostatic chuck component 2 from below (the other side in the stacking direction). The upper surface (support surface) 3a of the base 3 and the lower surface 2a of the electrostatic chuck component 2 face each other in the vertical direction (stacking direction) via the bonding layer 4. The base 3 supports the electrostatic chuck component 2 on the support surface 3a.

[0047] Alternatively, a flow path 3f for refrigerant circulation can be provided inside the base 3. The refrigerant flowing in the flow path 3f can be arbitrarily selected, such as a fluorinated inert liquid, water, He gas, or N2 gas. The flow path 3f extends along the support surface 3a. While cooling the entire base 3, the refrigerant in the flow path 3f also cools the electrostatic chuck component 2 via the support surface 3a.

[0048] The base 3 is connected to an external high-frequency power supply 5 via a matching device (not shown in the diagram), thus also serving as an internal electrode for plasma generation.

[0049] Figure 2 This is a schematic perspective view of the electrostatic chuck device 1, and an explanatory diagram mainly showing the base 3.

[0050] like Figure 1 , Figure 2 In the example shown, the base 3 has an inner peripheral portion 311 and an outer peripheral portion 312 that, when viewed from above, surrounds the outer side of the inner peripheral portion 311 in a closed loop. Furthermore, the base 3 may also have a middle portion 313, which, when viewed from above, is disposed between and in contact with both the inner peripheral portion 311 and the outer peripheral portion 312. Preferably, the inner peripheral portion, the outer peripheral portion, and the middle portion have the same thickness. Figure 1 and Figure 2 In the example shown, the base 3 is formed only by an inner peripheral portion, a middle portion, and an outer peripheral portion. The inner peripheral portion, the middle portion, and the outer peripheral portion, having the same thickness, are joined together in this order from the inside. The base 3 may also be formed only by the inner peripheral portion and the outer peripheral portion.

[0051] Comparing the thermal conductivity of different parts of the base 3, the thermal conductivity of the outer periphery 312 is higher than that of the inner periphery 311. Furthermore, the thermal conductivity of the middle part 313 is higher than that of the inner periphery 311 but lower than that of the outer periphery 312. That is, the thermal conductivity of the base 3 increases in the order of the inner periphery 311, the middle part 313, and the outer periphery 312, meaning that the outermost parts of the structure transfer heat more easily. Therefore, heat dissipation is more effective towards the outer edges.

[0052] Alternatively, as described later, the base 3 can also be formed by stacking multiple (e.g., three) conductive ceramic plates or green sheets and processing them. The multiple conductive ceramic plates or green sheets can have the same structure or properties, or they can have different structures or properties. The base 3 as a whole can satisfy the characteristic that the thermal conductivity of the outer periphery is higher than that of the inner periphery. For example, among the stacked multiple conductive ceramic plates or green sheets, at least one can be configured such that the thermal conductivity of its outer periphery is higher than that of its inner periphery, while the remaining conductive ceramic plates or green sheets are configured to have a uniform composition.

[0053] exist Figure 2 In the example of the base 3 shown, the inner peripheral portion 311 is circular when viewed from above, while the outer peripheral portion 312 and the middle portion 313 are respectively concentric annular (donut-shaped) rings with the inner peripheral portion 311 when viewed from above. The top-view area of ​​the inner peripheral portion 311 is preferably 55% to 95% of the total top-view area (planar area) of the base 3. With the top-view area of ​​the inner peripheral portion 311 within the above range, a range of 5% to 45% of the top-view area of ​​the base 3 becomes a region with a higher thermal conductivity than the inner peripheral portion 311, effectively cooling the periphery of the wafer W. Therefore, during plasma processing, it is easy to uniformly maintain the temperature of the center and periphery of the wafer W.

[0054] A flow path 311f, which forms part of the flow path 3f, is provided inside the inner peripheral portion 311. A flow path 312f, which forms part of the flow path 3f, is provided inside the outer peripheral portion 312. The flow paths 311f and 312f can be continuous or independently provided.

[0055] Each part of the base 3 (inner peripheral part 311, outer peripheral part 312, and middle part 313) is formed with conductive ceramic (hereinafter, sometimes simply referred to as "conductive ceramic") containing highly thermally conductive and electrically conductive materials. Figure 2The various portions of the base 3 shown are formed of mutually different conductive ceramics. The inner peripheral portion 311 is formed of a first conductive ceramic comprising a first high thermal conductivity material and a first conductive material. The outer peripheral portion 312 is formed of a second conductive ceramic comprising a second high thermal conductivity material and a second conductive material. The middle portion 313 is formed of a third conductive ceramic, which comprises the first high thermal conductivity material and the second high thermal conductivity material, as well as the first conductive material and the second conductive material.

[0056] The first and second high thermal conductivity materials can be the same or different materials. Similarly, the first and second high electrical conductivity materials can be the same or different materials. The thermal conductivity can also be adjusted by changing the composition, etc.

[0057] Regarding the material of the base 3, when the base 3 as a whole is set to 100% by volume, the volume ratio of the highly thermally conductive material to the electrically conductive material in each part of the base 3 is 30:70 to 70:30. The ratio can be 35:65 to 65:35, 40:60 to 60:40, or 45:55 to 55:45, etc.

[0058] By making the base 3 a conductive ceramic material, heat can be easily transferred from the electrostatic chuck component 2, thereby enabling an electrostatic chuck device that allows for easy temperature control of the wafer W supported by the electrostatic chuck component 2.

[0059] The material forming the base needs to have excellent thermal conductivity, electrical conductivity, and machinability; therefore, it has traditionally been made of metals such as aluminum. On the other hand, the dielectric substrate constituting the electrostatic chuck component uses ceramic as the forming material. Generally, the coefficient of thermal expansion of ceramic is much smaller than that of metal, so the difference in the coefficients of thermal expansion between a metal base and an electrostatic chuck component made of ceramic is large.

[0060] On the other hand, the base 3 used in the electrostatic chuck device 1 of this embodiment is made of conductive ceramic. Therefore, the difference in the coefficients of thermal expansion between the two can be reduced. Furthermore, this base 3 easily transfers heat from the electrostatic chuck component 2, thus enabling an electrostatic chuck device that facilitates temperature control of the wafer W. The ease with which the base 3, made of conductive ceramic, transfers heat was confirmed through simulations when the base 3 was of a uniform composition.

[0061] In the simulation, for electrostatic chuck device A with dielectric substrate 11 as an Al2O3-SiC composite sintered body and base 3 as aluminum, and electrostatic chuck device B with base 3 as an AlN-TiN composite sintered body as conductive ceramic, the heat transfer effect of base 3 was confirmed regarding plasma heat.

[0062] As a result, when the measurement temperature of the bonding layer 4 in the electrostatic chuck device A is set to T℃, the measurement temperature of the bonding layer 4 in the electrostatic chuck device B is T-50℃. Furthermore, regarding the measurement temperatures of the dielectric substrate 11, the wafer W, and the contact portion between the wafer W and the dielectric substrate 11, the electrostatic chuck device B is 50℃ lower than that of the electrostatic chuck device A. That is, it has been confirmed that by changing the forming material of the base 3 from the conventional metal to a conductive ceramic, plasma heat can be effectively released (removed).

[0063] The conductive materials (first conductive material, second conductive material) are preferably selected from at least one of the group consisting of SiC, TiO2, TiN, TiC, W, WC, Mo, MoC, Mo2C, TaC, TaN, Nb, NbC, VC, and C. Among these, TiN is preferred in terms of excellent plasma resistance.

[0064] The high thermal conductivity material (first high thermal conductivity material, second high thermal conductivity material) is preferably selected from at least one of the following groups: AlN, SiC, GaN, Al2O3, SmAlO3, Si3N4, Al(OH)3, MgO, Mg(OH)2, BN, ZnO, BeO, B4C, carbon (C), W, Mo, Nb, aluminum, copper, silver, and gold. Furthermore, when SiC, W, Mo, or Nb is used as the high thermal conductivity material, the conductive material is selected from materials other than those chosen for the high thermal conductivity material. For example, when SiC is selected as the high thermal conductivity material, a material other than SiC is selected as the conductive material. When SiC is used as the high thermal conductivity material, TiN can be selected as the conductive material, for example. Furthermore, high thermal conductivity indicates both high thermal conductivity and high heat dissipation.

[0065] Furthermore, in addition to including materials with high thermal conductivity and conductive materials, conductive ceramics may also include, to a extent that it does not impair the effect of the invention, a material that serves as the substrate when forming the conductive ceramic molded body as a third component. Examples of such materials include SiO2.

[0066] (Thermal conductivity of the base) The base 3 is preferably made of a material with a thermal conductivity of 40 W / m·K or higher, more preferably 50 W / m·K or higher and 110 W / m·K or lower. With a thermal conductivity within the above range, the input heat can be effectively released. Depending on the need, the lower limit can be 60 W / m·K or higher, 70 W / m·K or higher, 80 W / m·K or higher, or 90 W / m·K or higher. Depending on the need, the upper limit can be 100 W / m·K or lower, 90 W / m·K or lower, 80 W / m·K or lower, 70 W / m·K or lower, or 60 W / m·K or lower. The thermal conductivity of the base 3 described above represents an overall average value.

[0067] In the electrostatic chuck device 1, the outer peripheral portion 312 overlaps with the peripheral portion of the electrostatic chuck component 2 on a plane. This effectively cools the outer peripheral side (peripheral portion) of the wafer W, which is relatively prone to high temperatures, via the peripheral portion of the electrostatic chuck component 2, thereby reducing the in-plane temperature difference of the wafer W. The inner peripheral portion 311 and the middle portion 313, when viewed from above, are located further inward than the peripheral portion of the electrostatic chuck component 2.

[0068] The difference between the thermal conductivity of the inner peripheral portion 311 and the thermal conductivity of the outer peripheral portion 312 is preferably 15 W / m·K or more and 250 W / m·K or less, more preferably 20 W / m·K or more and 200 W / m·K or less. It can also be 30 W / m·K or more and 150 W / m·K or less, 40 W / m·K or more and 100 W / m·K or less, or 60 W / m·K or more and 80 W / m·K or less. Because the difference between the thermal conductivity of the inner peripheral portion 311 and the outer peripheral portion 312 is within the above range, the outer peripheral side of the wafer W is relatively easier to cool than the inner peripheral side, and the outer peripheral side is not overcooled. Therefore, according to this base 3, the outer peripheral side (peripheral portion) of the wafer W, which is relatively prone to high temperatures, can be effectively cooled, thereby reducing the in-plane temperature difference of the wafer W.

[0069] The thermal conductivity of the inner circumference 311 is preferably 20 W / m·K to 80 W / m·K, more preferably 40 W / m·K to 60 W / m·K, but is not limited to this example.

[0070] The thermal conductivity of the outer peripheral portion 312 is preferably 40 W / m·K to 120 W / m·K, more preferably 50 W / m·K to 100 W / m·K, but is not limited to this example.

[0071] The thermal conductivity of each part of the base 3 can be controlled by adjusting the volume ratio of highly thermally conductive materials in each part.

[0072] The thermal conductivity of the base and its components can be obtained in the following ways.

[0073] For example, the thermal conductivity of the inner circumference can be measured using a thermal dilatometer. Any thermal dilatometer can be selected; for example, a horizontal total expansion thermal dilatometer (model DIL402, manufactured by NETZSCH) can be used.

[0074] (Coefficient of thermal expansion of the base) The base 3 can be formed using a material that can reduce the difference in thermal expansion coefficient with that of the dielectric substrate 11, taking into account the thermal expansion coefficient of the dielectric substrate 11.

[0075] For example, when the main component of the dielectric substrate 11 is aluminum oxide and it is combined with silicon carbide, the coefficient of thermal expansion of the dielectric substrate 11 becomes the coefficient of thermal expansion of aluminum oxide (7.0 × 10⁻⁶). -6 / K~7.7×10 -6 / K) and the coefficient of thermal expansion of silicon carbide (4.0×10) -6 Between / K). In this case, when using a material with a higher coefficient of thermal expansion than alumina as the conductive material contained in the base 3, a material with a relatively lower coefficient of thermal expansion than alumina can be used as the high thermal conductivity material contained in the base 3. For example, AlN (coefficient of thermal expansion 4.5 × 10⁻⁶) is preferred. -6 / K).

[0076] The coefficient of thermal expansion of the base 3 as a whole is preferably 6.0 × 10⁻⁶. -6 / K or higher and 9.0×10 -6 Below / K. It can also be 6.5×10. -6 / K or higher and 8.5×10 -6 / K or less, 7.0×10 -6 / K or higher and 8.0×10 -6 / K and below. With the thermal expansion coefficient of the base 3 within the specified range, the thermal expansion difference with the dielectric substrate 11, which mainly contains aluminum oxide, is easily reduced. Even when heated during the plasma process, the internal stress is small, and damage such as interface peeling in the bonding layer is less likely to occur.

[0077] The difference between the coefficient of thermal expansion of the inner peripheral portion 311 and the coefficient of thermal expansion of the outer peripheral portion 312 is preferably less than 2 ppm / K, more preferably less than 1.5 ppm / K, and even more preferably less than 1 ppm / K. Ideally, the lower limit of the difference between the coefficients of thermal expansion of the inner peripheral portion 311 and the outer peripheral portion 312 is 0 ppm / K. By keeping the difference between the coefficients of thermal expansion of the inner peripheral portion 311 and the outer peripheral portion 312 within the above-mentioned range, damage at the interface between the inner peripheral portion 311 and the outer peripheral portion 312 can be suppressed.

[0078] The coefficient of thermal expansion of the inner circumference 311 is preferably, for example, 6.0 × 10⁻⁶. -6 / K~9.0×10 -6 / K, more preferably 6.5×10 -6 / K~8.5×10 -6 / K, further preferably 7.0×10 -6 / K~8.0×10 -6 / K, but not limited to this example.

[0079] The coefficient of thermal expansion of the outer periphery 312 is preferably, for example, 6.0 × 10⁻⁶. -6 / K~9.0×10 -6 / K, more preferably 6.5×10 -6 / K~8.5×10 -6 / K, further preferably 7.0×10 -6 / K~8.0×10 -6 / K, but not limited to this example.

[0080] In addition, the coefficients of thermal expansion of each part can be obtained, for example, in the following ways.

[0081] For example, regarding the coefficient of thermal expansion of the base or inner circumference, a 3mm × 3mm × 15mm test piece is obtained from the conductive ceramic plate. Using this test piece and a thermal expansion measuring device, such as a NETZSCH TD5000SA device, the change in diameter is measured as the temperature changes between 25℃ and 800℃ at a heating rate of 5℃ / min, and the coefficient of thermal expansion from 25℃ to 800℃ is calculated. Then, the calculated coefficient of thermal expansion is divided by the temperature change range (ΔT = 800℃ - 25℃ = 775℃) to obtain the coefficient of thermal expansion ( / K).

[0082] As an example, the base 3 can adopt a structure in which the inner peripheral portion 311 is an AlN-TiN composite sintered body and the outer peripheral portion 312 is an AlN-Mo composite sintered body.

[0083] The intermediate portion 313 possesses properties between the inner peripheral portion 311 and the outer peripheral portion 312 in terms of various physical properties such as thermal conductivity and coefficient of thermal expansion. The intermediate portion 313 comprises a first high thermal conductivity material of the inner peripheral portion 311 and a second high thermal conductivity material of the outer peripheral portion 312. In the intermediate portion 313, the volume proportion of the first high thermal conductivity material is less than that of the inner peripheral portion 311. Furthermore, in the intermediate portion 313, the volume proportion of the second high thermal conductivity material is less than that of the outer peripheral portion 312.

[0084] Similarly, the intermediate portion 313 includes a first conductive material in the inner peripheral portion 311 and a second conductive material in the outer peripheral portion 312. In the intermediate portion 313, the volume ratio of the first conductive material is smaller than that in the inner peripheral portion 311. Furthermore, in the intermediate portion 313, the volume ratio of the second conductive material is smaller than that in the outer peripheral portion 312.

[0085] In the middle portion 313, the thermal conductivity can increase from the inner peripheral portion 311 side toward the outer peripheral portion 312 side, or it can exhibit a uniform thermal conductivity. When the thermal conductivity increases from the inner peripheral portion 311 side toward the outer peripheral portion 312 side, it can increase gradually, it can increase in stages, or it can be in other ways.

[0086] To the extent that it does not impair the effects of the present invention, the base 3 may also contain a sintering aid. The sintering aid is any commonly added substance and is not particularly limited; for example, at least one selected from Y₂O₃, MgO, SiO₂, CaO, La₂O₃, Ce₂O₃, etc., may be listed. Among these, Y₂O₃, MgO, and SiO₂ are preferred.

[0087] The volume resistivity of base 3 is preferably 1.0 × 10⁻⁶. -6 Ω·cm or more and 1.0×10 -3 Below Ω·cm. It can also be 1.0 × 10⁻⁶. -5 Ω·cm or more and 1.0×10 -4 Below Ω·cm, etc. Sufficient conductivity can be obtained through the volume resistivity of the base 3 within the specified range.

[0088] The coefficient of thermal expansion of the base 3 as a whole is preferably the same as or almost the same as that of the dielectric substrate 11. The absolute value of the difference between the coefficient of thermal expansion of the base 3 and the coefficient of thermal expansion of the dielectric substrate 11 is preferably 2.0 or less, more preferably 1.5 or less, even more preferably 1.3 or less, and even more preferably 1.0 or less.

[0089] To improve plasma resistance, the surface of the base 3 is preferably subjected to anodizing treatment.

[0090] <Joint Layer> In this embodiment, the bonding layer 4 is formed of a metallic material and bonds the electrostatic chuck component 2 and the base 3. The bonding layer 4 can, for example, use an alloy as the forming material that, when the bonding layer 4 is 100% by volume, contains 50% to 99.98% Al or Ag and 0.02% to 40% by volume of at least one metal selected from the group consisting of Ti, Zr, and Hf. Because the bonding layer 4 contains at least one metal selected from the group consisting of Ti, Zr, and Hf, the molten alloy obtained by melting the material of the bonding layer 4 easily wets and spreads on the surface of the ceramic (electrostatic chuck component 2) during the bonding of the electrostatic chuck component 2 and the base 3, making bonding easier. Furthermore, because the bonding layer 4 contains the aforementioned metal, the metal and the ceramic (electrostatic chuck component 2) easily adhere tightly, suppressing the formation of voids at the interface and achieving a strong bond.

[0091] Furthermore, the connection between the electrostatic chuck component 2 and the base 3 can be arbitrarily selected. It can be achieved by diffusion bonding of components with each other, or by applying ceramic paste using printing and then bonding it using hot pressing.

[0092] Furthermore, in order to suppress the interface delamination between the electrostatic chuck component 2 and the bonding layer 4 caused by the difference in thermal expansion between the electrostatic chuck component 2 and the bonding layer 4, a stress-relieving layer can be provided between them using a material with a thermal expansion ratio between the electrostatic chuck component 2 and the bonding layer 4. This stress-relieving layer can also be provided between the base 3 and the bonding layer 4 according to the same technical concept.

[0093] The thickness of the bonding layer 4 can be selected arbitrarily, but it is preferably 0.005 mm or more and 0.5 mm or less.

[0094] When manufacturing the electrostatic chuck device 1, metal foil or a metal paste containing a binder in metal powder can be used as the material for the bonding layer 4. These materials are placed between the electrostatic chuck component 2 and the base 3, and heated to a temperature above the melting point of the metal material forming the bonding layer 4. The molten metal material wets and spreads between the electrostatic chuck component 2 and the base 3, thereby forming the bonding layer 4.

[0095] This bonding layer 4 is formed by brazing the electrostatic chuck component 2 and the base 3 using the material of the aforementioned bonding layer 4. During brazing, the opposing surfaces of the electrostatic chuck component 2 and the base 3 respectively come into contact with molten brazing filler metal and are heated to the melting temperature of the brazing filler metal (e.g., 800°C). Here, when the material of the base 3 is aluminum, the coefficient of thermal expansion of the material of the base 3 is approximately 20 × 10⁻⁶. -6 / K. On the other hand, the coefficient of thermal expansion of the electrostatic chuck component 2 is greater than that of alumina (7.0 × 10⁻⁶). -6 / K~7.7×10 -6 / K) small.

[0096] Therefore, it is envisioned that a large tensile stress is applied to the electrostatic chuck component 2 on the opposing surfaces of the electrostatic chuck component 2 and the base 3, which are in contact with the molten solder, due to the difference in the coefficient of thermal expansion of each surface. It is believed that due to this tensile stress, cracks may occur in the electrostatic chuck component 2.

[0097] In contrast, in the electrostatic chuck device 1, the base 3 is made of the aforementioned material, so when the electrostatic chuck component 2 and the base 3 are brazed, the electrostatic chuck component 2 is less prone to cracking.

[0098] Furthermore, the bonding layer 4 may also have a stacked structure in which a stress-relieving layer is sandwiched between a pair of bonding layers.

[0099] The stress-relieving layer is formed of a material that is easily plastically deformable, and it alleviates the thermal stress caused by the difference in the thermal expansion rates between the electrostatic chuck component 2 and the base 3. The stress-relieving layer uses a metal foil as the material, and the metal foil is selected from at least one metal selected from the group consisting of Cu, Al, and Ti.

[0100] Alternatively, a material with a small difference in coefficient of thermal expansion compared to Al2O3 constituting the electrostatic chuck component 2 can be used as the stress-relieving layer. For example, a material with a coefficient of thermal expansion similar to Al2O3 (7 × 10⁻⁶) could be used. -6 / K~7.7×10 -6 Materials with a small difference in K / L and used as stress-relieving layers include Ti (8.4 × 10⁻⁶ K / L). -6 / K), Nb (7.1×10 -6 / K), W (4.6×10 -6 / K).

[0101] The thickness of the stress-relieving layer can be chosen arbitrarily, but it is preferably 0.001 mm or more and 1 cm or less, more preferably 1 mm or more and 1 cm or less. By including the thickness of the stress-relieving layer within this range, thermal stress can be sufficiently relieved, and peeling between the electrostatic chuck component 2 and the base 3 can be suppressed.

[0102] The melting point of the materials in the pair of bonding layers is lower than that of the materials forming the stress-relieving layer. The pair of bonding layers can also be made of the same material. The pair of bonding layers can be made of the same material as bonding layer 4 described above.

[0103] The thickness of each pair of bonding layers is preferably greater than 0.005 mm and less than 0.5 mm.

[0104] By having a stress-relieving layer in the bonding layer 4, the stress generated at the interface between the base 3 and the electrostatic chuck component 2 is further relieved, which can suppress the peeling of the bonding layer 4.

[0105] Furthermore, without impairing the effect of the invention, the electrostatic chuck device 1 can appropriately adopt a known structure as the structure of the electrostatic chuck device.

[0106] <Method for manufacturing the base> Figures 3-7 This is an explanatory diagram of the manufacturing method of base 3.

[0107] (Manufacturing method of conductive ceramic plate) Figures 3-5An example of a method for manufacturing a conductive ceramic plate, which serves as the material for the base 3, is shown. The conductive ceramic plate can be obtained by mixing a highly thermally conductive material and a conductive material within a specified range to obtain a raw material powder, and then using the obtained raw material powder to manufacture ceramics by a known method. For example, it can be manufactured through the following steps: a step of mixing a highly thermally conductive material and a conductive material in a volume ratio of 30:70 to 60:40 to obtain a raw material powder (mixing step); a step of applying pressure to the obtained raw material powder to obtain a molded body (forming step); and a step of obtaining a conductive ceramic plate by pressure sintering the obtained molded body (pressure sintering step).

[0108] There are no particular limitations on the average primary particle size of the high thermal conductivity material, as long as a conductive ceramic plate can be obtained. For example, a high thermal conductivity material with a particle size of 0.5 μm or larger and 5 μm or smaller can be used. The particle size can also be 0.8 μm or larger and 4.5 μm or smaller, 1.0 μm or larger and 4.0 μm or smaller, 1.5 μm or larger and 3.5 μm or smaller, 2.0 μm or larger and 3.0 μm or smaller, etc.

[0109] Regarding the average primary particle size of the conductive material, there is no particular limitation as long as a conductive ceramic plate can be obtained; for example, conductive materials with a particle size of 0.5 μm or larger and 5 μm or smaller can be used. The particle size can also be 0.8 μm or larger and 4.5 μm or smaller, 1.0 μm or larger and 4.0 μm or smaller, 1.5 μm or larger and 3.5 μm or smaller, 2.0 μm or larger and 3.0 μm or smaller, etc. A preferred particle size can be selected according to the required conditions.

[0110] (Mixed process) In the mixing process, the mixing method is not particularly limited as long as the raw material powder can be obtained by mixing the highly thermally conductive material and the electrically conductive material. However, in order to prevent the highly thermally conductive material and the electrically conductive material from agglomerating, it is preferable to appropriately mix the dispersant or solvent and mix them using a mixing device such as a disperser. The mixing device is not particularly limited, and conventional devices such as ball mills, planetary mills, bead mills, and atomizers can be used.

[0111] A drying process can also be added after mixing the raw material powder. The drying method can be natural drying, using a dryer, or spray drying to form particles of 30μm to 100μm from the raw material powder.

[0112] Alternatively, after the mixing or drying process, the raw material powder can be heated in a non-oxidizing environment at a temperature above 300°C and below 600°C to remove impurities such as moisture, solvents, and dispersants contained in the raw material powder.

[0113] As a non-oxidizing environment, an inert gas environment using nitrogen or argon is preferred. Furthermore, when performing the above-mentioned heating in an inert gas environment, in order to efficiently remove the generated impurities from the system, it is preferable to use a so-called gas flow, which circulates ambient gas, for heating treatment.

[0114] Using the above method, the raw material powder for the inner peripheral portion 311 and the raw material powder for the outer peripheral portion 312 are prepared respectively.

[0115] (Forming process) In the forming process, pressure is applied to the obtained raw material powder by means of mold forming method or the shape of the target conductive ceramic plate, according to the shape of the target conductive ceramic plate, and preferably uniaxial forming (uniaxial pressing forming) is performed to obtain a molded body with the desired shape.

[0116] In this embodiment, such as Figure 3 As shown, after a cylindrical inner frame F is configured inside the mold M, the inner periphery 311A ​​of the inner frame F is filled with raw material powder 311A, and the outer periphery 312A of the inner frame F is filled with raw material powder 312A.

[0117] The inner frame F has a shape and size corresponding to the shape and size of the inner periphery 311 of the base 3. Figure 2 In the case of the base 3 shown, a cylindrical inner frame F with the same or nearly the same diameter as the inner circumference 311 is used.

[0118] Next, as Figure 4 As shown, the inner frame F is pulled out from the mold M. As a result, raw material powder 311A ​​and raw material powder 312A flow into the location of the inner frame F and mix with each other, producing raw material powder 313A in the intermediate portion 313. In the raw material powder 313A, the composition (e.g., the volume ratio of conductive materials) can vary continuously from the inside to the outside of the mold M, or it can vary discontinuously, or it can be a uniform composition.

[0119] Thus, raw material powder 313A is a mixed powder obtained by mixing raw material powder 311A ​​and raw material powder 312A, and the volume ratio of the high thermal conductivity material and the electrical conductivity material is respectively the ratio between raw material powder 311A ​​and raw material powder 312A. Furthermore, the thickness of the inner frame F is related to the volume of the middle part 313. If the inner frame F is thick, the width of the formed middle part 313 is also wide; if the inner frame F is thin, the width of the formed middle part 313 is also narrow.

[0120] Next, as Figure 5 As shown, the upper part of the mold M, which is filled with raw material powder 311A, raw material powder 312A, and raw material powder 313A, is closed, and pressure P is applied for uniaxial pressing.

[0121] (Pressure sintering process) In the pressure sintering process, the shaped body obtained through the forming process is subjected to pressure sintering under vacuum or a non-oxidizing environment. This is achieved by compacting the body at a pressure of any choice, such as 5 MPa or higher, while simultaneously heating it to a temperature of any choice, such as 1600°C or higher. This operation allows for the sintering of highly thermally or electrically conductive materials contained in the shaped body, resulting in a dense sintered body with few pores. The aforementioned temperature can be selected as needed, and can be 1600–1900°C or 1650–1800°C, etc. The heating time can be selected arbitrarily, for example, 1–5 hours, 3–8 hours, or 6–12 hours.

[0122] Thus, raw material powders 311A, 312A, and 313A become the inner peripheral portion 311, the outer peripheral portion 312, and the middle portion 313, respectively, and a conductive ceramic plate that serves as the material for the base 3 can be obtained. The conductive ceramic plates preferably each have a constant thickness that can be arbitrarily selected.

[0123] (Method 1 for manufacturing the base) In manufacturing method 1 of this embodiment, the base 3 is obtained by processing a conductive ceramic plate obtained by the above method into the desired shape of the base 3. Figure 6 , Figure 7 This is an explanatory diagram illustrating an example of a manufacturing method for the base 3. The base 3 may be composed of portions derived from two conductive ceramic plates, or portions derived from three conductive ceramic plates. Preferably, at least one conductive ceramic plate has an inner periphery, a middle portion, and an outer periphery.

[0124] First, such as Figure 6 As shown, two conductive ceramic plates are prepared. On at least one side 30a of the prepared pair of conductive ceramic plates 30, a continuous strip-shaped groove 30x is formed when viewed from above. The groove 30x can be formed using any chosen method, such as known forming electrical discharge machining or contour machining.

[0125] The composition and characteristics of the "pair of conductive ceramic plates" can be the same or different. In this embodiment, the pair of conductive ceramic plates have the same composition, top view shape, and arrangement of the inner periphery 311, outer periphery 312, and middle portion 313, but differ in thickness and the presence or absence of grooves. Alternatively, in the pair of conductive ceramic plates 30 and 31, only one conductive ceramic plate may have an inner periphery, middle portion, and outer periphery, while the other conductive ceramic plate may not have an inner periphery, middle portion, and outer periphery, but instead have a plate with a uniform composition. For example, the portion of the other conductive ceramic plate corresponding to the inner periphery or outer periphery may be formed of the same material. For example, the other conductive ceramic plate may be formed of a material with high thermal conductivity, or it may be formed of the same material as the outer periphery.

[0126] The grooves 30x can all have the same depth, or they can have different depths.

[0127] Next, with the groove 30x facing another conductive ceramic plate 31, the pair of conductive ceramic plates 30 and 31 are overlapped and diffusely bonded. The space enclosed by the facing surfaces 31a of the groove 30x and the conductive ceramic plate 31 becomes the internal flow path 3f for refrigerant flow (see reference). Figure 1 In addition, diffusion bonding refers to a method of bonding conductive ceramic plates by tightly adhering them together, applying pressure at a temperature below the melting point of the base material, and utilizing atomic diffusion between the bonding surfaces.

[0128] (Method 2 for manufacturing the base) In addition, as another method, such as Figure 7 As shown, three conductive ceramic plates are first prepared, and through holes 35x, which appear as a continuous strip when viewed from top, are formed from one side of one of the substrates 35. The through holes 35x can be formed using known electrical discharge wire cutting (EDM) processes.

[0129] Next, the substrate 35 is clamped and joined using the remaining two conductive ceramic plates 36 and 37. The space enclosed by the through hole 35x and the facing surfaces 36a and 37a of the conductive ceramic plates 36 and 37 becomes the internal flow path 3f for refrigerant flow (see reference). Figure 1 ).

[0130] Thus, the base 3 can be manufactured. By setting the conductive ceramic plate 30, conductive ceramic plate 31, or substrate 35 and conductive ceramic plate 36 and conductive ceramic plate 37 to have the same composition, the obtained base 3 becomes a single composition without adhesives or other materials.

[0131] The obtained base 3 is joined to the electrostatic chuck component 2 via a joining component described later, thereby enabling the manufacture of the electrostatic chuck device 1.

[0132] Alternatively, in this example, at least one of the substrate 35 and the conductive ceramic plates 36 and 37 may have an inner peripheral portion, a middle portion, and an outer peripheral portion, while the remaining plates or substrates may be configured to lack the inner peripheral portion, middle portion, and outer peripheral portion, and have an overall uniform composition. For example, only at least one of the substrate 35 and the conductive ceramic plate 36 may have an inner peripheral portion and an outer peripheral portion, or have an inner peripheral portion, a middle portion, and an outer peripheral portion. The portions of the remaining conductive ceramic plates corresponding to the inner peripheral portion or the outer peripheral portion may be formed of the same material. For example, at least one of the remaining conductive ceramic plates may be formed of a material with high thermal conductivity, or it may be formed of the same material as the outer peripheral portion.

[0133] The above describes a method for manufacturing a base by uniaxially pressing powdered material and sintering it under high pressure and high temperature, but other methods can also be used.

[0134] (Method 3 for manufacturing the base) For example, it is also possible to produce green sheets (sheets that are flexible before sintering) by adding resin or the like to the powder of the material, and to manufacture the base by stacking the green sheets and calcining them.

[0135] In this case, for example, after fabricating a green sheet 1 for the inner periphery and a green sheet 2 for the outer periphery, the green sheet 1 is machined into a circular shape when viewed from above, and the green sheet 2 is machined into a ring shape when viewed from above. Then, the two are combined and fired to form a base. At this time, the peripheral portion of the circular component made from the green sheet 1 and the inner periphery of the ring-shaped component made from the green sheet 2 can be arbitrarily shaped. For example, the peripheral portion and the inner periphery can be made into complementary inclined shapes, or more specifically, they can be machined into conical surfaces with complementary inclined surfaces. By using green sheets with this structure, the two can be firmly joined. Furthermore, by forming in this way, green sheets with an inner periphery and an outer periphery, or green sheets with an inner periphery, a middle portion, and an outer periphery, can be obtained.

[0136] Furthermore, when using the green sheet as described above, after processing the green sheet to form a structure corresponding to the groove 30x or through hole 35x, the base can be manufactured by selecting processed and / or unprocessed green sheets as needed and then stacking and firing them. In this case, by changing the number or position of the interconnected through holes in the stacked green sheets, the depth or position of the flow path can be controlled. The number of overlapping green sheets can be arbitrarily selected; one or more green sheets can be green sheets with an inner circumference and an outer circumference, or green sheets with an inner circumference, a middle portion, and an outer circumference.

[0137] Figure 8 , Figure 9 This is a plan view showing a modified example of a conductive ceramic plate and base.

[0138] Figure 8 The conductive ceramic plate 38 of the modified example 1 shown has: an inner peripheral portion 321; an outer peripheral portion 322 that surrounds the outer side of the inner peripheral portion 321 in a closed loop when viewed from above; and a middle portion 323 that is disposed between the inner peripheral portion 321 and the outer peripheral portion 322 when viewed from above, and is in contact with the inner peripheral portion 321 and the outer peripheral portion 322.

[0139] Unlike the base 3 described above, the conductive ceramic plate 38 has a central portion 323 that, when viewed from above, is not annular but has multiple (four equally spaced along the circumference in the figure) arcuate portions 323A along an imaginary circle VC, and multiple (four equally spaced along the circumference in the figure) protrusions 323B disposed between the arcuate portions 323A. The protrusions 323B protrude further outward than the imaginary circle VC. The four protrusions 323B have the same shape when viewed from above. The center of the imaginary circle VC coincides with the center of the base 3B. Furthermore, the number of arcuate portions 323A and protrusions 323B can be arbitrarily selected, for example, 4 to 6, 7 to 12, or 13 to 20.

[0140] This conductive ceramic plate 38 can be used and through Figure 6 , Figure 7 The method shown is used to manufacture the base 3B. When manufacturing the base 3B, the conductive ceramic plates 38 that overlap in the vertical direction can be made such that their respective protrusions 323B completely overlap each other when viewed from above, or a portion of the protrusions 323B can overlap each other, or they can be offset along the circumferential direction so that the protrusions 323B do not overlap each other.

[0141] and, Figure 9 The conductive ceramic plate 39 of the modified example 2 shown has, like the other examples, an inner peripheral portion 331; an outer peripheral portion 332 surrounding the outer side of the inner peripheral portion 331; and a middle portion 333 disposed between the inner peripheral portion 331 and the outer peripheral portion 332, and connected to the inner peripheral portion 331 and the outer peripheral portion 332.

[0142] In the conductive ceramic plate 39, the central portion 333, when viewed from above, has a wavy shape in which convex portions 333A and concave portions 333B are periodically repeated along the circumferential direction. Here, assuming the largest imaginary circle VC1 inscribed within the central portion 333 when viewed from above, and the smallest imaginary circle VC2 concentric with imaginary circle VC1 and circumscribed outside the central portion 333, the imaginary circle at the midpoint between imaginary circles VC1 and VC2 is designated as imaginary circle VC3. The radius D3 of imaginary circle VC3 is the average of the radius D1 of imaginary circle VC1 and the radius D2 of imaginary circle VC2. The convex portion 333A is the portion that protrudes further outward than the imaginary circle VC3, and the concave portion 333B is the portion that is recessed further inward than the imaginary circle VC3. The number of alternating convex portions 333A and concave portions 333B can be arbitrarily selected, for example, 6 to 10, 11 to 16, or 17 to 24.

[0143] This conductive ceramic plate 39 can be used and through Figure 6 , Figure 7The method shown is used to manufacture the base 3C. When manufacturing the base 3C, the conductive ceramic plates 39 that overlap in the vertical direction can be made such that their respective protrusions 333A completely overlap each other when viewed from above, or a portion of the protrusions 333A can overlap each other, or they can be offset along the circumferential direction so that the protrusions 333A do not overlap each other.

[0144] In the base (temperature adjustment component) 3 of the above structure, the temperature of the wafer W placed on the periphery of the electrostatic chuck device 1 can be appropriately adjusted. Furthermore, the electrostatic chuck device 1 of the above structure has the base 3 as described above, allowing for appropriate temperature adjustment at the periphery of the wafer W.

[0145] Furthermore, although the above embodiment is provided with a middle portion having the aforementioned shape, it may not have a middle portion, or the existence of the middle portion may not be apparent when the base is viewed from above. In this case, on each base in the above example, the shape of the boundary portion between the inner and outer peripheral portions can be set to be the same as the shape of the edge of the middle portion when the middle portion is present (e.g., the shape of the boundary portion between the middle portion and the outer peripheral portion).

[0146] The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to these examples. The shapes or combinations of the constituent components shown in the above examples are just one example, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

[0147] Explanation of reference numerals in the attached figures 1-Electrostatic chuck device 2-Electrostatic Chuck Components 2a- Lower surface of the electrostatic chuck component 3, 3B, 3C - Base (Temperature Adjustment Component) 3a - Upper surface of the base (support surface) 3f-Flow path 4- Bonding layer 5-High Frequency Power Supply 11-Dielectric substrate 13-Adsorption Electrode 15-Adsorption Electrode 21-First Adsorption Section 21a - The mounting surface of the wafer 21x-flow path 22-Second Adsorption Section 22a - Upper surface of the second adsorption section 22x - The groove of the second adsorption section 30, 35, 36, 37, 38, 39 - Conductive ceramic plates One side of a 30a-conductive ceramic plate 30x-groove section 31 - Another conductive ceramic plate 31a, 36a, 37a - the opposing surfaces of another conductive ceramic plate 35x - Through Hole 211-Protrusion 311, 321, 331 - Inner Peripheral Part 311A, 312A, 313A - Raw material powder 311f-Inner peripheral flow path 312, 322, 332-Peripheral part 312f-Peripheral flow path 313, 323, 333 - Middle Section 323A - Arc Part 323B-convex part 333A-convex part 333B-Concave D1, D2, D3 - Radius of the imaginary circle F-Inner Frame FR-Focusing Ring M-mold Ma-internal P - Pressure VC - Imaginary Circle VC1 - Maximum Imaginary Circle VC2 - Minimum Imaginary Circle VC3 - Imaginary circle in the middle W-chip.

Claims

1. A temperature adjustment component that supports an electrostatic chuck component, wherein the temperature adjustment component, At least a portion of the interior and exterior circumferences have different thermal conductivity. The inner circumference is formed of a first conductive ceramic comprising a first high thermal conductivity material and a first conductive material. The outer periphery is formed of a second conductive ceramic comprising a second high thermal conductivity material and a second conductive material, and when viewed from above, it surrounds the outer side of the inner periphery in a closed loop. The thermal conductivity of the outer periphery is higher than that of the inner periphery.

2. The temperature adjustment component according to claim 1, comprising: A middle portion, when viewed from above, is disposed between the inner peripheral portion and the outer peripheral portion, and is in contact with both the inner peripheral portion and the outer peripheral portion. The middle portion is formed of a third conductive ceramic, the third conductive ceramic comprising the first high thermal conductivity material and the second high thermal conductivity material, as well as the first conductive material and the second conductive material. The thermal conductivity of the middle portion is higher than that of the inner peripheral portion and lower than that of the outer peripheral portion.

3. The temperature adjustment component according to claim 1 or 2, wherein, The top view area of ​​the inner periphery is more than 55% and less than 95% of the top view area of ​​the temperature adjustment component.

4. The temperature adjustment component according to claim 1 or 2, wherein, The difference between the thermal conductivity of the inner circumference and the thermal conductivity of the outer circumference is more than 15 W / m·K and less than 250 W / m·K.

5. The temperature adjustment component according to claim 1 or 2, wherein, The difference between the coefficient of thermal expansion of the inner circumference and the coefficient of thermal expansion of the outer circumference is less than 2 ppm / K.

6. An electrostatic chuck device, comprising: The temperature adjustment component as described in claim 1 or 2; and The electrostatic chuck component has a dielectric substrate and electrodes for electrostatic adsorption, and is supported by the temperature adjustment component. The electrostatic chuck component overlaps with the outer periphery when viewed from above.

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