Ceramic bonded body, electrostatic chuck device, and method for manufacturing ceramic bonded body

Abstract

A ceramic joint (1) comprises: a pair of ceramic plates (2, 3) containing a conductive material; a conductive layer (4) and an insulating layer (5) between the pair of ceramic plates (2, 3); and a pair of intermediate layers (6, 7) between the pair of ceramic plates (2, 3) and the conductive layer (4) and in contact with the pair of ceramic plates (2, 3) and the conductive layer (4).

Description

Technical Field

[0001] The present invention relates to a ceramic joint body, an electrostatic chuck device and a method for manufacturing the ceramic joint body.

[0002] This application claims priority based on Japanese Patent Application No. 2020-15793 filed in Japan on January 31, 2020, the contents of which are incorporated herein by reference. Background Art

[0003] Conventionally, in semiconductor manufacturing processes for manufacturing semiconductor devices such as IC, LSI, and VLSI, a plate-shaped sample such as a silicon wafer is fixed to an electrostatic chuck member having an electrostatic chuck function by electrostatic adsorption and subjected to a predetermined treatment.

[0004] For example, when the plate-like sample is subjected to an etching process or the like in a plasma environment, the surface of the plate-like sample may become hot due to the heat of the plasma, and problems such as cracking (breaking) of the resist film on the surface may occur.

[0005] Therefore, in order to maintain the temperature of the plate-shaped sample at a desired constant temperature, an electrostatic chuck device is used. The electrostatic chuck device includes an electrostatic chuck component and a temperature adjustment base component. The temperature adjustment base component, which has a flow path for circulating a temperature control cooling medium inside a metal component, is bonded to the lower surface of the electrostatic chuck component via a silicone adhesive to integrate them.

[0006] In the electrostatic chuck device, a temperature adjustment cooling medium is circulated in the flow path of the temperature adjustment base member to perform heat exchange, that is, the temperature of a plate-like sample fixed to the upper surface of the electrostatic chuck member is maintained at a desired constant temperature, and electrostatic adsorption is performed, and various plasma treatments are performed on the plate-like sample.

[0007] The electrostatic chuck component of the electrostatic chuck device is required to have corrosion resistance, heat resistance, plasma resistance, durability against thermal cycle load, etc. As a component of the electrostatic chuck device that achieves these excellent properties, an electrostatic chuck component consisting of an electrostatic chuck base body, which is formed of a composite dielectric ceramic obtained by adding a conductive material to an insulating ceramic material, an internal electrode built into the electrostatic chuck base body, and a power supply terminal provided to be connected to the internal electrode is known (for example, refer to Patent Documents 1 and 2).

[0008] Prior art literature

[0009] Patent Literature

[0010] Patent Document 1: Japanese Patent Application Publication No. 2003-152062

[0011] Patent Document 2: Japanese Patent Application Publication No. 2007-051045 Summary of the invention

[0012] Technical issues to be solved by the invention

[0013] Although the material of the internal electrode of the electrostatic chuck electrode built-in base described in Patent Documents 1 and 2 is not particularly limited, the material is a high-melting-point material with high conductivity, and can also be a composite sintered body containing an insulating ceramic material and a conductive high-melting-point material. The bonding surface between the composite dielectric ceramic of the electrostatic chuck substrate and the internal electrode is usually bonded after the surface is polished. Therefore, the conductive material is exposed on each surface of the bonding interface between the electrostatic chuck substrate and the internal electrode. Therefore, a conductive path is easily formed in the interface between the electrostatic chuck substrate and the internal electrode (conductive layer), and the insulation is reduced. Therefore, there is a technical problem of generating insulation breakdown (discharge) at the bonding interface between the composite dielectric ceramic and the internal electrode.

[0014] The present invention has been made in view of the above circumstances, and an object thereof is to provide a ceramic bonded body that suppresses dielectric breakdown (discharge) at the bonding interface between a ceramic plate and a conductive layer, an electrostatic chuck device including the ceramic bonded body, and a method for manufacturing the ceramic bonded body.

[0015] Means for solving technical problems

[0016] In order to solve the above-mentioned technical problems, the first method of the present invention provides a ceramic joint body, which comprises: a pair of ceramic plates containing conductive materials; a conductive layer and an insulating layer between the pair of ceramic plates; and a pair of intermediate layers between the pair of ceramic plates and the conductive layer and in contact with the pair of ceramic plates and the conductive layer.

[0017] The first aspect of the present invention also preferably has the following features. Two or more of the following features may be combined with each other.

[0018] In one embodiment of the present invention, the conductive layer may be composed of a conductive material and an insulating material, and the insulating layer and the intermediate layer may be composed of an insulating material.

[0019] In one embodiment of the present invention, when the thickness of the conductive layer is t1 and the total thickness of the intermediate layer is t2, the thickness ratio R1 of the intermediate layer defined by the following formula (1) may be 3% or more.

[0020] R1=t2 / t1×100(%) (1)

[0021] In one embodiment of the present invention, the insulating material constituting the insulating layer may have an average primary particle size of 1.6 μm or more and 10.0 μm or less.

[0022] In one embodiment of the present invention, the ceramic plate may be composed of a composite of aluminum oxide and silicon carbide.

[0023] In one embodiment of the present invention, the insulating material included in the conductive layer, the insulating layer, and the intermediate layer may be composed only of aluminum oxide.

[0024] In one embodiment of the present invention, the conductive material contained in the conductive layer can be selected from Mo 2 At least one selected from the group consisting of C, Mo, WC, W, TaC, Ta, SiC, carbon black, carbon nanotubes, and carbon nanofibers.

[0025] A second aspect of the present invention provides an electrostatic chuck device comprising an electrostatic chuck member formed of ceramic and a temperature adjustment base member formed of metal joined via an adhesive layer, the electrostatic chuck member being composed of the ceramic bonded body according to one embodiment of the present invention.

[0026] A third embodiment of the present invention provides a method for manufacturing a ceramic joint, which comprises: a process of preparing a first ceramic plate containing a conductive material and a second ceramic plate containing a conductive material; a process of applying an intermediate layer forming paste on one surface of the first ceramic plate to form a first intermediate layer coating; a process of applying a conductive layer forming paste on the surface of the first intermediate layer coating opposite to the surface in contact with the first ceramic plate to form a conductive layer coating; a process of applying an intermediate layer forming paste on the surface of the conductive layer coating opposite to the surface in contact with the first intermediate layer coating to form a second intermediate layer coating; a process of stacking the second ceramic plate on the surface of the second intermediate layer coating opposite to the surface in contact with the conductive layer coating; and a process of heating and pressurizing the stack including the first ceramic plate, the first intermediate layer coating, the conductive layer coating, the second intermediate layer coating and the second ceramic plate in the thickness direction.

[0027] The manufacturing method of the third aspect can appropriately manufacture the ceramic bonded body of the first aspect.

[0028] Effects of the Invention

[0029] According to the present invention, it is possible to provide a ceramic bonded body that suppresses dielectric breakdown (discharge) from occurring at a bonding interface between a ceramic plate and a conductive layer, an electrostatic chuck device including the ceramic bonded body, and a method for manufacturing the ceramic bonded body. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic cross-sectional view showing an example of a ceramic bonded body according to a preferred embodiment of the present invention.

[0031] Figure 2 It is a schematic cross-sectional view showing an example of a ceramic bonded body according to a preferred embodiment of the present invention.

[0032] Figure 3 It is a schematic cross-sectional view showing an example of an electrostatic chuck device according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0033] Preferred examples of embodiments of the ceramic bonded body, the electrostatic chuck device, and the method for producing the ceramic bonded body of the present invention will be described.

[0034] In addition, the present embodiment is only specifically described for a better understanding of the purpose of the invention, and does not limit the present invention unless otherwise specified. The quantity, position, size, value, ratio, material, etc. can be changed, omitted, and added without departing from the scope of the present invention.

[0035] [Ceramic joint body]

[0036] (First embodiment)

[0037] Below, while referring to Figure 1 , while describing preferred examples of the ceramic bonded body according to one embodiment of the present invention.

[0038] In all the following drawings, the dimensions, ratios, etc. of each component may be appropriately changed in some cases to make the drawings easier to understand.

[0039] Figure 1 2 is a schematic cross-sectional view showing a ceramic joint body according to the present embodiment. Figure 1 As shown, the ceramic assembly 1 of this embodiment comprises: a pair of ceramic plates 2, 3, containing conductive material; a conductive layer 4 and an insulating layer 5, between the pair of ceramic plates 2, 3; and intermediate layers 6, 7, between the pair of ceramic plates 2, 3 and the conductive layer 4 and the insulating layer 5, and connected to the pair of ceramic plates 2, 3, and the conductive layer 4 and the insulating layer 5.

[0040] Hereinafter, the ceramic plate 2 is referred to as a first ceramic plate 2 , the ceramic plate 3 is referred to as a second ceramic plate 3 , the intermediate layer 6 is referred to as a first intermediate layer 6 , and the intermediate layer 7 is referred to as a second intermediate layer 7 .

[0041] like Figure 1As shown, in the ceramic bonded body 1, the first ceramic plate 2, the first intermediate layer 6, the combination of the conductive layer 4 and the insulating layer 5, the second intermediate layer 7, and the second ceramic plate 3 are stacked in order from the lower side of the figure. That is, the ceramic bonded body 1 is a bonded body in which the first ceramic plate 2 and the second ceramic plate 3 are bonded and integrated via the first intermediate layer 6, the conductive layer 4, the insulating layer 5, and the second intermediate layer 7. In the figure, the insulating layer 5 is arranged on the periphery of the conductive layer 4. The upper and lower main surfaces of the conductive layer 4 and the insulating layer 5 and the interface between the conductive layer 4 and the insulating layer 5 are in contact with the first intermediate layer 6 and the second intermediate layer 7 arranged above and below these layers 4 and 5.

[0042] It is preferable that the overlapping surfaces of the first ceramic plate 2 and the second ceramic plate 3 have the same shape. The shape of the ceramic plate can be arbitrarily selected, and may be, for example, circular, doughnut-shaped, quadrilateral, or rectangular, but is not limited to these examples.

[0043] The thickness of the first ceramic plate 2 and the second ceramic plate 3 is not particularly limited and can be arbitrarily selected and appropriately adjusted according to the purpose of the ceramic joint body 1. For example, although 0.3 to 3.0 mm, 0.4 to 2.5 mm, and 0.5 to 1.5 mm are cited as examples, they are not limited to these examples. The thickness of the first ceramic plate 2 and the second ceramic plate 3 can be the same or different.

[0044] The first ceramic plate 2 and the second ceramic plate 3 have the same composition or the same main component. That is, the first ceramic plate 2 and the second ceramic plate 3 may have the same composition or different compositions. The first ceramic plate 2 and the second ceramic plate 3 are composed of a composite of an insulating substance and a conductive substance. The composite is preferably composed only of an insulating substance and a conductive substance. The insulating substance contained in the first ceramic plate 2 and the second ceramic plate 3 is not particularly limited, but for example, a material selected from alumina (Al 2 O 3 ), aluminum nitride (AlN), yttrium oxide (Y 2 O 3 ), yttrium aluminum garnet (YAG), etc. Furthermore, the conductive material contained in the first ceramic plate 2 and the second ceramic plate 3 is not particularly limited, but for example, silicon carbide (SiC), titanium oxide (TiO 2 ), titanium nitride (TiN), titanium carbide (TiC), carbon (C), carbon nanotubes (CNT), carbon nanofibers, rare earth oxides, rare earth fluorides, etc.

[0045] The proportion of the insulating material in the composite can be arbitrarily selected, preferably 80 to 99% by mass, preferably 85 to 98% by mass, but is not limited to these examples. The proportion can be, for example, 80 to 95% by mass, or 83 to 90% by mass. The proportion of the conductive material in the composite can be arbitrarily selected, preferably 1 to 20% by mass, preferably 2 to 15% by mass, but is not limited to these examples. The proportion can be, for example, 3 to 12% by mass, or 5 to 10% by mass.

[0046] The material (composite) of the first ceramic plate 2 and the second ceramic plate 3 preferably has a volume resistivity of 10 13 Ω·cm or more and 10 15 Ω·cm or less, and has mechanical strength and durability against corrosive gases and plasma. Examples of such materials include aluminum oxide (Al 2 O 3 ) sintered body, aluminum nitride (AlN) sintered body, aluminum oxide (Al 2 O 3 )-silicon carbide (SiC) composite sintered body, but from the perspective of dielectric properties at high temperatures, high corrosion resistance, plasma resistance and heat resistance, aluminum oxide (Al 2 O 3 )-Silicon carbide (SiC) composite sintered body.

[0047] The conductive layer 4 is, for example, a layer that can be used as the following electrodes: a plasma generating electrode for plasma treatment by passing high-frequency power, an electrostatic chuck electrode for generating electric charge and fixing a plate-shaped sample by electrostatic adsorption force, and / or a heater electrode for heating a plate-shaped sample by passing electricity and heating. The shape (shape of the conductive layer 4 when viewed from above (from the thickness direction)) and size (thickness or area of ​​the conductive layer 4 when viewed from above (from the thickness direction)) of the conductive layer 4 are not particularly limited and can be appropriately adjusted according to the purpose of the ceramic joint 1. The thickness of the conductive layer 4 can be arbitrarily selected, but for example, it is preferably 5 to 200 μm, more preferably 8 to 150 μm, and further preferably 10 to 100 μm, but it is not limited to these examples. The shape of the conductive layer 4 can be arbitrarily selected, but for example, it can also be circular, doughnut-shaped, quadrilateral, rectangular, etc. when viewed from above.

[0048] The conductive layer 4 is composed of a conductive substance and an insulating substance. The conductive layer 4 is preferably a conductive composite material composed only of a conductive substance and an insulating substance.

[0049] The conductive material contained in the conductive layer 4 is preferably selected from molybdenum carbide (Mo 2At least one of the group consisting of molybdenum (C), molybdenum (Mo), tungsten carbide (WC), tungsten (W), tantalum carbide (TaC), tantalum (Ta), silicon carbide (SiC), carbon black, carbon nanotubes and carbon nanofibers. The conductive material contained in the conductive layer 4 is at least one selected from the group consisting of the above substances, so that the conductivity of the conductive layer can be ensured.

[0050] The insulating material contained in the conductive layer 4 is not particularly limited, but examples thereof include alumina (Al 2 O 3 ), aluminum nitride (AlN), yttrium oxide (Y 2 O 3 ), yttrium aluminum garnet (YAG), etc. The insulating material contained in the conductive layer 4 is also preferably the same as the insulating material of the first ceramic plate 2 and the second ceramic plate 3.

[0051] The conductive layer 4 is composed of a conductive material and an insulating material, so that the bonding strength with the first ceramic plate 2 and the second ceramic plate 3 and the mechanical strength as an electrode are enhanced. The insulating material contained in the conductive layer 4 is aluminum oxide (Al 2 O 3 ), which can maintain dielectric properties at high temperatures, high corrosion resistance, plasma resistance and heat resistance.

[0052] The content ratio (blending ratio) of the conductive material and the insulating material in the conductive layer 4 is not particularly limited and can be appropriately adjusted according to the application of the ceramic joint 1 .

[0053] The ratio of the insulating material used in the conductive layer 4 can be arbitrarily selected, and is preferably 20 to 60% by mass, preferably 25 to 55% by mass, relative to the total amount of the conductive material and the insulating material, but is not limited to these examples. The ratio can be, for example, 35 to 50% by mass, 40 to 45% by mass, etc.

[0054] The proportion of the conductive material used in the conductive layer 4 can be arbitrarily selected, and is preferably 40 to 80 mass %, preferably 45 to 75 mass %, relative to the total amount, but is not limited to these examples. The proportion may be, for example, 50 to 65 mass %, 43 to 60 mass %, etc.

[0055] The insulating layer 5 is a layer provided for joining the boundary portion between the first ceramic plate 2 and the second ceramic plate 3, that is, the outer edge region outside the portion where the conductive layer 4 is formed. The shape of the insulating layer 5 (the shape of the insulating layer 5 when viewed from above (viewed from the thickness direction)) is not particularly limited and can be appropriately adjusted according to the shape of the conductive layer 4.

[0056] In the ceramic joint body 1 of the present embodiment, the thickness of the insulating layer 5 is preferably equal to the thickness of the conductive layer 4. The shape of the insulating layer 5 can be arbitrarily selected, but may be, for example, circular, doughnut-shaped, quadrilateral, rectangular, etc. when viewed from above, and is not limited to these examples. The shape of the insulating layer 5 may also be a shape surrounding the conductive layer 4 when viewed from above.

[0057] The insulating layer 5 is composed only of an insulating material.

[0058] The insulating material constituting the insulating layer 5 is not particularly limited, but is preferably the same as the insulating material of the first ceramic plate 2 and the second ceramic plate 3. The insulating material constituting the insulating layer 5 may be, for example, alumina (Al 2 O 3 ), aluminum nitride (AlN), yttrium oxide (Y 2 O 3 ), yttrium aluminum garnet (YAG), etc. The insulating material constituting the insulating layer 5 is preferably only aluminum oxide (Al 2 O 3 ) is formed. The insulating material constituting the insulating layer 5 is aluminum oxide (Al 2 O 3 ), appropriately maintaining dielectric properties at high temperatures, high corrosion resistance, plasma resistance and heat resistance.

[0059] The average primary particle size of the insulating material constituting the insulating layer 5 is preferably 1.6 μm or more and 10.0 μm or less, more preferably 1.6 μm or more and 8.0 μm or less, and further preferably 1.6 μm or more and 6.0 μm or less. The value may also be 1.6 to 2.5 μm, 2.5 to 3.5 μm, 3.5 to 5.0 μm, etc. In addition, the average primary particle size of the insulating material constituting the insulating layer 5 may refer to the average primary particle size of the powder of the insulating material as the material forming the insulating layer 5 (i.e., as the raw material).

[0060] If the average primary particle size of the insulating material constituting the insulating layer 5 is 1.6 μm or more, sufficient withstand voltage can be obtained. On the other hand, if the average primary particle size of the insulating material constituting the insulating layer 5 is 10.0 μm or less, grinding and other processability are good.

[0061] The first intermediate layer 6 is located between the first ceramic plate 2 and the conductive layer 4 and the insulating layer 5, and is an intermediate layer provided to insulate the first ceramic plate 2 from the conductive layer 4. The second intermediate layer 7 is located between the second ceramic plate 3 and the conductive layer 4 and the insulating layer 5, and is an intermediate layer provided to insulate the second ceramic plate 3 from the conductive layer 4. The shapes of the first intermediate layer 6 and the second intermediate layer 7 (the shapes of the first intermediate layer 6 and the second intermediate layer 7 when viewed from above (viewed from the thickness direction)) are not particularly limited, and can be appropriately adjusted according to the shapes of the conductive layer 4 and the insulating layer 5. For example, the shape can be circular, donut-shaped, quadrilateral, or rectangular, but is not limited to these examples. The shapes of the first intermediate layer 6 and the second intermediate layer 7 can be the same as the conductive layer 4 when viewed from above, or can be the same as the shape formed by combining the conductive layer 4 and the insulating layer 5.

[0062] The thickness of the first intermediate layer 6 and the thickness of the second intermediate layer 7 can be arbitrarily selected and may be different from each other or may be equal to each other, but are preferably equal to each other.

[0063] When the thickness of the conductive layer 4 is set to t1 and the total thickness of the first intermediate layer 6 and the second intermediate layer 7 is set to t2, the ratio (R1) of the total thickness t2 of the first intermediate layer 6 and the second intermediate layer 7 defined by the following formula (1) to the thickness t1 of the conductive layer 4 is preferably greater than 3%, and more preferably greater than 8%.

[0064] R1=t2 / t1×100(%) (1)

[0065] When R1 is 3% or more, a conductive path is not formed at the interface between the ceramic plate and the internal electrode, and therefore sufficient lateral insulation resistance can be obtained.

[0066] Furthermore, R1 is preferably 50% or less, and more preferably 40% or less. If R1 exceeds 50%, the conductive layer 4 cannot obtain a sufficient thickness, so the uniform adsorption force, temperature uniformity, etc. are reduced, which is not preferred. As needed, the ratio (R1) can be 3 to 30%, 3 to 20%, or 3 to 15%.

[0067] The thickness t1 of the conductive layer and the total t2 of the thickness of the first intermediate layer and the thickness of the second intermediate layer may be values ​​obtained by observing a cross section of the ceramic bonded body through SEM.

[0068] The first intermediate layer 6 and the second intermediate layer 7 are made of an insulating material. The first intermediate layer 6 and the second intermediate layer 7 are preferably made of only an insulating material. The first intermediate layer 6 and the second intermediate layer 7 may have the same composition or different compositions.

[0069] The insulating material constituting the first intermediate layer 6 and the second intermediate layer 7 is not particularly limited, but is preferably the same as the insulating material of the first ceramic plate 2 and the second ceramic plate 3. For example, an insulating material selected from alumina (Al 2 O 3 ), aluminum nitride (AlN), yttrium oxide (Y 2 O 3 ), yttrium aluminum garnet (YAG), etc. The materials of the first intermediate layer 6 and the second intermediate layer 7 may be the same or different, but are preferably the same. The insulating material constituting the first intermediate layer 6 and the second intermediate layer 7 is preferably only aluminum oxide (Al 2 O 3 ) is formed. The insulating material forming the first intermediate layer 6 and the second intermediate layer 7 is aluminum oxide (Al 2 O 3 ), which can ensure dielectric properties at high temperatures, high corrosion resistance, plasma resistance and heat resistance. The intermediate layer is also preferably formed of the same material as the insulating layer.

[0070] According to the ceramic joint body 1 of the present embodiment, it comprises: a pair of ceramic plates 2, 3 containing a conductive material; a conductive layer 4 and an insulating layer 5 interposed between the ceramic plates 2, 3; and intermediate layers 6, 7 interposed between the ceramic plates 2, 3 and the conductive layer 4, and in contact with the ceramic plates 2, 3 and the conductive layer 4. Therefore, the ceramic plates 2, 3 and the conductive layer 4 are insulated by the intermediate layers 6, 7, so that the dielectric breakdown (discharge) generated in the joint interface between the ceramic plates 2, 3 and the conductive layer 4 can be suppressed.

[0071] (Second embodiment)

[0072] Figure 2 2 is a schematic cross-sectional view showing a preferred example of a ceramic joint body according to the present embodiment. Figure 2 In, with Figure 1 The same components of the ceramic bonded body shown are denoted by the same reference numerals, and repeated descriptions are omitted.

[0073] like Figure 2 As shown, the ceramic joint body 10 of this embodiment includes: a pair of ceramic plates 2, 3, containing a conductive material; a conductive layer 4 and an insulating layer 5, which are interposed between the pair of ceramic plates 2, 3; and intermediate layers 6, 7, which are interposed between the pair of ceramic plates 2, 3 and the conductive layer 4, and are in contact with the ceramic plates 2, 3 and the conductive layer 4. The insulating layer 5 can be formed on the periphery of the conductive layer 4 and can be in contact with each other.

[0074] like Figure 2As shown, in the ceramic bonded body 10, in the region where the conductive layer 4 is provided when viewed from above, the first ceramic plate 2, the first intermediate layer 6, the conductive layer 4, the second intermediate layer 7, and the second ceramic plate 3 are stacked in sequence. Furthermore, in the region where the insulating layer 5 is provided when viewed from above, the first ceramic plate 2, the insulating layer 5, and the second ceramic plate 3 are stacked in sequence. That is, with respect to the ceramic bonded body 10, in the region where the conductive layer 4 is provided, the first ceramic plate 2 and the second ceramic plate 3 are bonded and integrated via the first intermediate layer 6, the conductive layer 4, and the second intermediate layer 7. And in the region where the insulating layer 5 is provided, it is a bonded body in which the first ceramic plate 2 and the second ceramic plate 3 are bonded and integrated via the insulating layer 5.

[0075] According to the ceramic bonded body 10 of the present embodiment, the same effects as those of the ceramic bonded body 1 of the first embodiment can be obtained.

[0076] [Method for producing ceramic bonded body]

[0077] The manufacturing method of the ceramic joint body of the present embodiment comprises: a step of applying an intermediate layer forming paste on one surface of a first ceramic plate containing a conductive material to form a first intermediate layer coating film (hereinafter referred to as the "first step"); a step of applying a conductive layer forming paste on the surface of the first intermediate layer coating film on the side opposite to the surface in contact with the first ceramic plate to form a conductive layer coating film (hereinafter referred to as the "second step"); a step of applying an intermediate layer forming paste on the surface of the conductive layer coating film on the side opposite to the surface in contact with the first intermediate layer coating film. The process of forming a second intermediate layer coating (hereinafter referred to as the "third process"); the process of laminating a second ceramic plate containing a conductive material on the surface of the second intermediate layer coating opposite to the surface in contact with the conductive layer coating (hereinafter referred to as the "fourth process"); and the process of heating and pressurizing the stack including the first ceramic plate, the first intermediate layer coating, the conductive layer coating, the second intermediate layer coating and the second ceramic plate in the thickness direction (hereinafter referred to as the "fifth process").

[0078] Below, while referring to Figure 1 , while describing a method for manufacturing the ceramic joint body according to the present embodiment.

[0079] The first intermediate layer 6 is formed in the first step. That is, in the first step, an intermediate layer forming paste is applied to a predetermined position of one surface 2a of the first ceramic plate 2 by an arbitrarily selected coating method such as screen printing to form a coating film (first intermediate layer coating film) that becomes the first intermediate layer 6. The intermediate layer 6 may be provided on the entire surface 2a of the ceramic plate 2.

[0080] As the intermediate layer forming paste, it is preferable to use a paste obtained by dispersing an insulating substance forming the first intermediate layer 6 in an arbitrarily selected solvent.

[0081] As the solvent contained in the intermediate layer forming paste, isopropyl alcohol or the like is used. The ratio of the above substances in the intermediate layer forming paste can be arbitrarily selected, but is preferably 20 to 70% by mass, and more preferably 30 to 50% by mass.

[0082] The conductive layer 4 is formed in the second step. That is, in the second step, a conductive layer forming paste is applied to a predetermined position of a surface 6a on the opposite side of the surface in contact with the first ceramic plate 2, which is a coating film to become the first intermediate layer 6 formed on one surface 2a of the first ceramic plate 2, by an arbitrarily selected coating method such as a screen printing method, to form a coating film (conductive layer coating film) to become the conductive layer 4.

[0083] As the conductive layer forming paste, a paste obtained by dispersing a conductive substance and an insulating substance forming the conductive layer 4 in a solvent is used.

[0084] As the solvent contained in the conductive layer forming paste, isopropyl alcohol or the like is used. The ratio of the conductive substance and the insulating substance in the conductive layer forming paste is preferably 10 to 30% by mass, and more preferably 20 to 30% by mass.

[0085] Furthermore, the insulating layer 5 is also formed in the second step. That is, in the second step, an insulating layer forming paste is applied to a predetermined position of a surface 6a on the opposite side of the surface in contact with the first ceramic plate 2, which is a coating film to become the first intermediate layer 6 formed on one surface 2a of the first ceramic plate 2, by an arbitrarily selected coating method such as a screen printing method, to form a coating film (insulating layer coating film) to become the insulating layer 5.

[0086] As the insulating layer forming paste, a paste obtained by dispersing an insulating substance forming the insulating layer 5 in a solvent is used.

[0087] As the solvent contained in the paste for forming the insulating layer, isopropyl alcohol or the like is used. The total ratio of the conductive material and the insulating material in the paste for forming the conductive layer can be selected arbitrarily, but is preferably 20 to 70% by mass, and more preferably 30 to 50% by mass. In addition, the paste for forming the insulating layer can be applied first, or the paste for forming the conductive layer can be applied first, or these pastes can be applied at the same time. Regarding the two pastes, the next paste can be applied after the first applied paste is dried, or it can be applied before drying. The conductive layer 4 and the insulating layer 5 are preferably formed adjacent to each other.

[0088] The second intermediate layer 7 is formed in the third step. That is, in the third step, an intermediate layer forming paste is applied to the surface 4a of the coating film to be the conductive layer 4 opposite to the surface in contact with the coating film to be the first intermediate layer 6 and the surface 5a of the coating film to be the insulating layer 5 opposite to the surface in contact with the coating film to be the first intermediate layer 6 by an arbitrarily selected coating method such as a screen printing method, thereby forming a coating film to be the second intermediate layer 7 (second intermediate layer coating film).

[0089] As the intermediate layer forming paste, a paste obtained by dispersing an insulating substance forming the second intermediate layer 7 in a solvent is used.

[0090] As the solvent contained in the paste for forming the intermediate layer, isopropyl alcohol or the like is used. The preferred ratio of the above substances in the paste for forming the intermediate layer 7 is the same as the preferred conditions for the intermediate layer 6 .

[0091] In the fourth step, the surface 3a of the second ceramic plate 3 is stacked to face the surface of the coating film to be the second intermediate layer 7 opposite to the surface in contact with the coating film to be the conductive layer 4 and the coating film to be the insulating layer 5.

[0092] The first to fourth steps may or may not include a drying step of drying the applied paste to a desired state.

[0093] In the fifth step, the laminate including the first ceramic plate 2, the coating film to be the first intermediate layer 6, the coating film to be the conductive layer 4, the coating film to be the insulating layer 5, the coating film to be the second intermediate layer 7, and the second ceramic plate 3 is heated and pressurized in the thickness direction. The environment when the laminate is heated and pressurized in the thickness direction is preferably a vacuum or an atmosphere of Ar, He, N 2 Inert environment.

[0094] The temperature (heat treatment temperature) for heating the laminate can be arbitrarily selected, but is preferably 1600° C. or higher and 1900° C. or lower, and more preferably 1650° C. or higher and 1850° C. or lower. It may also be 1700° C. or higher and 1800° C. or lower. If the heating temperature of the laminate is 1600° C. or higher and 1900° C. or lower, the solvent contained in each coating film can be volatilized to appropriately form the first intermediate layer 6, the conductive layer 4, the insulating layer 5, and the second intermediate layer 7 between the first ceramic plate 2 and the second ceramic plate 3. Furthermore, the first ceramic plate 2 and the second ceramic plate 3 can be appropriately bonded and integrated via the first intermediate layer 6, the conductive layer 4, the insulating layer 5, and the second intermediate layer 7.

[0095] The pressure (pressing force) for pressing the laminate in the thickness direction can be arbitrarily selected, but is preferably 1.0 MPa to 50.0 MPa, more preferably 3.0 MPa to 35.0 MPa, and even more preferably 5.0 MPa to 20.0 MPa.

[0096] If the pressure applied to the laminate in the thickness direction is greater than or equal to 1.0 MPa and less than or equal to 50.0 MPa, the first intermediate layer 6, the conductive layer 4, the insulating layer 5, and the second intermediate layer 7 that are closely attached to each other can be appropriately formed between the first ceramic plate 2 and the second ceramic plate 3. Furthermore, the first ceramic plate 2 and the second ceramic plate 3 can be appropriately bonded and integrated via the first intermediate layer 6, the conductive layer 4, the insulating layer 5, and the second intermediate layer 7.

[0097] [Electrostatic chuck device]

[0098] Below, while referring to Figure 3 , while explaining an electrostatic chuck device involved in one embodiment of the present invention.

[0099] Figure 3 2 is a schematic cross-sectional view showing an example of an electrostatic chuck device according to the present embodiment. Figure 3 In, with Figure 1 The same components of the ceramic bonded body shown are denoted by the same reference numerals, and repeated descriptions are omitted.

[0100] like Figure 3 As shown, the electrostatic chuck device 100 of the present embodiment comprises: a disk-shaped electrostatic chuck member 102; a disk-shaped temperature adjustment base member 103, which adjusts the electrostatic chuck member 102 to a desired temperature; and an adhesive layer 104, which integrates the electrostatic chuck member 102 and the temperature adjustment base member 103. In the electrostatic chuck device 100 of the present embodiment, the electrostatic chuck member 102 is constituted by, for example, the ceramic bonded body 1 or the ceramic bonded body 10 of the above-mentioned embodiment. Here, the case where the electrostatic chuck member 102 is constituted by the ceramic bonded body 1 is described.

[0101] In the following description, the relative positions of the components are sometimes indicated by referring to the placement surface 111 a side of the placement plate 111 as “upper” and the temperature adjustment base member 103 side as “lower”.

[0102] [Electrostatic chuck parts]

[0103] The electrostatic chuck component 102 comprises: a loading plate 111, the upper surface of which is provided as a loading surface 111a for loading a plate-shaped sample such as a semiconductor chip and is formed of ceramic; a supporting plate 112, provided on the surface side of the loading plate 111 opposite to the loading surface 111a; an electrostatic adsorption electrode 113, clamped between these loading plates 111 and the supporting plate 112; an annular insulating material 114, clamped by the loading plate 111 and the supporting plate 112 and surrounding the electrostatic adsorption electrode 113; and a power supply terminal 116, provided in a fixing hole 115 of the temperature adjustment base component 103 in a manner connected to the electrostatic adsorption electrode 113.

[0104] In the electrostatic chuck component 102 , the mounting plate 111 may be equivalent to the second ceramic plate 3 , the support plate 112 may be equivalent to the first ceramic plate 2 , the electrostatic adsorption electrode 113 may be equivalent to the conductive layer 4 , and the insulating material 114 may be equivalent to the insulating layer 5 .

[0105] [Loading plate]

[0106] A plurality of protrusions (not shown) for supporting plate-shaped samples such as semiconductor wafers are appropriately erected on the loading surface 111a of the loading plate 111 (the second ceramic plate 3). Furthermore, an annular protrusion having a quadrilateral cross section may be provided around the peripheral edge of the loading surface 111a of the loading plate 111 so as to prevent leakage of cooling gas such as helium (He). Furthermore, a plurality of protrusions having the same height as the annular protrusion and having a circular cross section and a roughly rectangular longitudinal section may be provided in the area surrounded by the annular protrusion on the loading surface 111a. In this way, the loading plate 111 can be appropriately processed.

[0107] The thickness of the mounting plate 111 can be arbitrarily selected, but is preferably 0.3 mm or more and 3.0 mm or less, more preferably 0.4 mm or more and 2.5 mm or less, and further preferably 0.5 mm or more and 1.5 mm or less. If the thickness of the mounting plate 111 is 0.3 mm or more, the withstand voltage is excellent. On the other hand, if the thickness of the mounting plate 111 is 3.0 mm or less, the electrostatic adsorption force of the electrostatic chuck component 102 will not decrease, and the thermal conductivity between the plate-like sample placed on the mounting surface 111a of the mounting plate 111 and the temperature adjustment base component 103 will not decrease, and the temperature of the plate-like sample being processed can be maintained at a preferred constant temperature.

[0108] [Support plate]

[0109] The support plate 112 (first ceramic plate 2 ) supports the placement plate 111 and the electrostatic attraction electrode 113 from below.

[0110] The thickness of the support plate 112 is preferably 0.3 mm or more and 3.0 mm or less, more preferably 0.4 mm or more and 2.5 mm or less, and more preferably 0.5 mm or more and 1.5 mm or less. If the thickness of the support plate 112 is 0.3 mm or more, sufficient voltage resistance can be ensured. On the other hand, if the thickness of the support plate 112 is 3.0 mm or less, the electrostatic adsorption force of the electrostatic chuck component 102 will not decrease, and the thermal conductivity between the plate-like sample placed on the placing surface 111a of the placing plate 111 and the temperature adjustment base component 103 will not decrease, and the temperature of the plate-like sample being processed can be maintained at a preferred constant temperature.

[0111] [Electrode for electrostatic adsorption]

[0112] In the electrostatic attraction electrode 113 (conductive layer 4 ), an electrostatic attraction force for holding the plate-shaped sample on the mounting surface 111 a of the mounting plate 111 is generated by applying a voltage.

[0113] The thickness of the electrostatic adsorption electrode 113 can be arbitrarily selected, but is preferably 5 μm or more and 200 μm or less, more preferably 8 μm or more and 150 μm or less, and further preferably 10 μm or more and 100 μm or less. It can be 20 μm or more and 80 μm or 40 μm or more and 60 μm or less. If the thickness of the electrostatic adsorption electrode 113 is 5 μm or more, sufficient conductivity can be ensured. On the other hand, if the thickness of the electrostatic adsorption electrode 113 is 200 μm or less, the thermal conductivity between the plate-like sample placed on the mounting surface 111a of the mounting plate 111 and the temperature adjustment base member 103 will not decrease, and the temperature of the plate-like sample being processed can be maintained at a desired constant temperature. In addition, the plasma permeability will not decrease, and plasma can be stably generated.

[0114] [Insulation material]

[0115] The insulating material 114 (insulating layer 5 ) is used to surround the electrostatic attraction electrode 113 to protect the electrostatic attraction electrode 113 from the corrosive gas and its plasma.

[0116] The placement plate 111 and the support plate 112 are bonded and integrated with each other through the electrostatic attraction electrode 113 by the insulating material 114 .

[0117] [Power supply terminal]

[0118] The power supply terminal 116 is used to apply a voltage to the electrostatic attraction electrode 113 .

[0119] The number, shape, etc. of the power supply terminals 116 are arbitrarily determined according to the form of the electrostatic attraction electrode 113, that is, whether it is a monopolar type or a bipolar type.

[0120] The material of the power supply terminal 116 is not particularly limited as long as it is a conductive material with excellent heat resistance. As the material of the power supply terminal 116, it is preferred that the material has a thermal expansion coefficient close to the thermal expansion coefficient of the electrostatic adsorption electrode 113 and the support plate 112, for example, metal materials such as Kovar alloy, niobium (Nb), and various conductive ceramics are suitably used.

[0121] [Conductive adhesive layer]

[0122] The conductive adhesive layer 117 is provided in the fixing hole 115 of the temperature adjustment base member 103 and in the through hole 118 of the support plate 112. The conductive adhesive layer 117 is interposed between the electrostatic attraction electrode 113 and the power supply terminal 116 to electrically connect the electrostatic attraction electrode 113 and the power supply terminal 116.

[0123] The conductive adhesive constituting the conductive adhesive layer 117 can be arbitrarily selected, and preferably includes a conductive substance such as carbon fiber or metal powder, and a resin.

[0124] The resin contained in the conductive adhesive can be arbitrarily selected without particular limitation as long as it is a resin that is not easily subjected to cohesive failure due to thermal stress, and examples thereof include silicone resins, acrylic resins, epoxy resins, phenolic resins, polyurethane resins, and unsaturated polyester resins.

[0125] Among these, silicone resins are preferably used from the viewpoint of high elasticity and low cohesion failure due to thermal stress changes.

[0126] [Temperature adjustment base member]

[0127] The temperature adjustment base member 103 is a thick disk-shaped member formed of at least one of metal and ceramic. The frame of the temperature adjustment base member 103 is a structure that also serves as an internal electrode for plasma generation. A gas barrier is formed inside the frame of the temperature adjustment base member 103 to allow water, He gas, N 2 A flow path 121 in which a cooling medium such as gas circulates.

[0128] The frame of the temperature adjustment base member 103 is connected to an external high frequency power source 122. A power supply terminal 116 surrounded by an insulating material 123 is fixed to the fixing hole 115 of the temperature adjustment base member 103 via an insulating material 123. The power supply terminal 116 is connected to an external DC power source 124.

[0129] The material constituting the temperature adjustment base member 103 is not particularly limited as long as it is a metal having excellent thermal conductivity, electrical conductivity, and processability or a composite material containing these metals. As the material constituting the temperature adjustment base member 103, for example, aluminum (Al), copper (Cu), stainless steel (SUS), titanium (Ti), etc. are preferably used.

[0130] Preferably, at least the surface of the temperature adjustment base member 103 exposed to plasma is treated with an aluminum oxide film or coated with a polyimide resin. More preferably, the entire surface of the temperature adjustment base member 103 is treated with an aluminum oxide film or coated with a resin.

[0131] By performing an alumina film treatment or resin coating on the temperature adjustment base member 103, the plasma resistance of the temperature adjustment base member 103 is improved and abnormal discharge can be prevented. Therefore, the plasma resistance stability of the temperature adjustment base member 103 is improved and the surface damage of the temperature adjustment base member 103 can be prevented.

[0132] [Adhesive layer]

[0133] The adhesive layer 104 is a layer that bonds and integrates the electrostatic chuck portion 102 and the cooling base portion 103 .

[0134] The thickness of the adhesive layer 104 can be arbitrarily selected, but is preferably 100 μm or more and 200 μm or less, and more preferably 130 μm or more and 170 μm or less.

[0135] When the thickness of adhesive layer 104 is within the above range, the bonding strength between electrostatic chuck portion 102 and cooling base portion 103 can be sufficiently maintained. In addition, the thermal conductivity between electrostatic chuck portion 102 and cooling base portion 103 can be sufficiently ensured.

[0136] The material of the adhesive layer 104 can be arbitrarily selected, and is formed of, for example, a cured product obtained by heating and curing a silicone resin composition, an acrylic resin, an epoxy resin, or the like.

[0137] The silicone resin composition is a silicon compound having a siloxane bond (Si—O—Si), and is a resin excellent in heat resistance and elasticity, and therefore is more preferred.

[0138] As such a silicone-based resin composition, a silicone resin having a thermal curing temperature of 70° C. to 140° C. is particularly preferred.

[0139] Here, if the thermal curing temperature is lower than 70°C, when the electrostatic chuck portion 102 and the cooling base portion 103 are bonded in a mutually opposed state, curing will not proceed sufficiently during the bonding process, and there is a possibility that the workability will be deteriorated, so it is not preferred. On the other hand, if the thermal curing temperature exceeds 140°C, the thermal expansion difference between the electrostatic chuck portion 102 and the cooling base portion 103 is large, and the stress between the electrostatic chuck portion 102 and the cooling base portion 103 increases, so there is a possibility that peeling will occur between them, so it is not preferred.

[0140] According to the electrostatic chuck device 100 of the present embodiment, since the electrostatic chuck member 102 is formed of the ceramic bonded body 1 , it is possible to suppress the occurrence of dielectric breakdown (discharge) in the electrostatic chuck member 102 .

[0141] Hereinafter, a method for manufacturing the electrostatic chuck device according to the present embodiment will be described.

[0142] An electrostatic chuck component 102 composed of the ceramic bonded body 1 obtained in the above manner is prepared.

[0143] An adhesive made of a silicone resin composition is applied to a predetermined region of one main surface 103a of the cooling base portion 103. Here, the amount of the adhesive applied is adjusted so that the electrostatic chuck portion 102 and the cooling base portion 103 can be bonded and integrated.

[0144] Examples of a method for applying the adhesive include manual application using a doctor blade or the like, a bar coating method, a screen printing method, and the like.

[0145] After the adhesive is applied to one main surface 103 a of the cooling base 103 , the electrostatic chuck unit 102 (ceramic bonded body 1 ) and the cooling base 103 on which the adhesive is applied are stacked.

[0146] Then, the upright power supply terminal 116 is inserted and fitted into the fixing hole 115 bored in the cooling base portion 103 .

[0147] Next, the electrostatic chuck portion 102 is pressed against the cooling base portion 103 at a predetermined pressure to integrally bond the electrostatic chuck portion 102 and the cooling base portion 103. Thus, the electrostatic chuck portion 102 and the cooling base portion 103 are integrally bonded via the adhesive layer 104.

[0148] Thus, the electrostatic chuck device 100 of the present embodiment can be obtained in which the electrostatic chuck portion 102 and the cooling base portion 103 are bonded and integrated via the adhesive layer 104 .

[0149] In addition, the plate-shaped sample involved in this embodiment is not limited to a semiconductor wafer, and can be, for example, a glass substrate for a flat panel display (FPD) such as a liquid crystal display (LCD), a plasma display (PDP), an organic EL display, etc. And, the electrostatic chuck device of this embodiment can be designed according to the shape and size of the substrate.

[0150] Example

[0151] Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[0152] [Example 1]

[0153] "Production of ceramic bonded bodies"

[0154] A mixed powder of 91 mass % alumina powder and 9 mass % silicon carbide powder is prepared, molded, and sintered to produce ceramic plates (first ceramic plate, second ceramic plate) consisting of a disc-shaped alumina-silicon carbide composite sintered body (a composite of alumina and silicon carbide) with a diameter of 450 mm and a thickness of 5.0 mm.

[0155] The paste for forming an intermediate layer was applied to one surface of the first ceramic plate by screen printing to form a first intermediate layer coating film.

[0156] As the intermediate layer forming paste, a paste prepared by dispersing aluminum oxide powder in isopropyl alcohol was used. The content of the aluminum oxide powder in the intermediate layer forming paste was set to 50% by mass.

[0157] Next, a conductive layer forming paste is applied to a predetermined position of the first intermediate layer coating formed on one surface of the first ceramic plate on the side opposite to the surface in contact with the first ceramic plate by screen printing, thereby forming a conductive layer coating. Furthermore, an insulating layer forming paste is applied to a predetermined position of the first intermediate layer coating formed on one surface of the first ceramic plate on the side opposite to the surface in contact with the first ceramic plate by screen printing, thereby forming an insulating layer coating. The insulating layer and the conductive layer are formed in a non-overlapping manner. Furthermore, the shape of the conductive layer when viewed from above is set to a circular shape. The shape of the insulating layer is set to a shape surrounding the periphery of the conductive layer. The periphery of the insulating layer is set to be equal to the periphery of the first ceramic plate. That is, it is formed so that their peripheries are consistent when viewed from above. Furthermore, the thickness of the insulating layer is set to be the same as the thickness of the conductive layer coating.

[0158] As the paste for forming the conductive layer, a paste obtained by dispersing aluminum oxide powder and molybdenum carbide powder in isopropyl alcohol was used. The content of aluminum oxide powder in the paste for forming the conductive layer was set to 25% by mass, and the content of molybdenum carbide powder was set to 25% by mass. As the paste for forming the insulating layer, a paste obtained by dispersing aluminum oxide powder having an average primary particle size of 2.0 μm in isopropyl alcohol was used. The content of aluminum oxide powder in the paste for forming the insulating layer was set to 50% by mass.

[0159] Next, the intermediate layer forming paste is applied to the surface of the conductive layer coating opposite to the surface in contact with the first intermediate layer coating and the surface of the insulating layer coating opposite to the surface in contact with the first intermediate layer coating by screen printing, thereby forming a second intermediate layer coating.

[0160] Next, a second ceramic plate is laminated on the surface of the second intermediate layer coating film opposite to the surface in contact with the conductive layer coating film and the insulating layer coating film.

[0161] Next, in an argon environment, the laminate including the first ceramic plate, the first intermediate layer coating, the conductive layer coating, the insulating layer coating, the second intermediate layer coating, and the second ceramic plate was heated and pressurized in the thickness direction. The heat treatment temperature was set to 1700° C., the pressure was set to 10 MPa, and the heat treatment and pressurization time was set to 2 hours.

[0162] Through the above process, we obtained Figure 1 The ceramic bonded body of Example 1 shown in the figure. In the obtained ceramic bonded body, the ratio (R1) of the sum of the thickness of the first intermediate layer and the thickness of the second intermediate layer t2 defined by the following formula (1) to the thickness t1 of the conductive layer is 4%. The thickness t1 of the conductive layer and the sum of the thickness of the first intermediate layer and the thickness of the second intermediate layer t2 are values ​​obtained by observing the cross section of the ceramic bonded body with a SEM.

[0163] R1=t2 / t1×100(%) (1)

[0164] (Insulation evaluation)

[0165] The insulation properties of the ceramic bonded body were evaluated as follows.

[0166] A carbon tape is attached to the side surface of the ceramic assembly (the side surface in the thickness direction of the ceramic assembly) in contact with the first ceramic plate, the first intermediate layer, the insulating layer, the second intermediate layer and the second ceramic plate. In addition, since the conductive layer is surrounded by the insulating layer, it is not in contact with the carbon tape.

[0167] The first ceramic plate and the first intermediate layer are penetrated in the thickness direction thereof to form a through electrode extending from the surface of the first ceramic plate opposite to the surface in contact with the first intermediate layer to the conductive layer. The through electrode is provided in contact with the conductive layer.

[0168] Voltage was applied to the ceramic joint body through the carbon tape and the through-electrode, and the voltage at which the ceramic joint body broke down (discharged) was measured. Specifically, RF voltage was applied and maintained for 10 minutes under a voltage of 3000V, and then voltage was gradually applied and maintained for 10 minutes at a rate of 500V each time. When the measured current value exceeded 0.1mA (milliampere), it was considered to be a breakdown. The results are shown in Table 1.

[0169] [Example 2]

[0170] The average primary particle size of the aluminum oxide powder contained in the insulating layer is set to 3.0 μm, and the heat treatment temperature of the stack including the first ceramic plate, the first intermediate layer coating, the conductive layer coating, the insulating layer coating, the second intermediate layer coating and the second ceramic plate is set to 1750°C. Except for this, the ceramic joint body of Example 2 is obtained in the same manner as Example 1.

[0171] The insulation properties of the ceramic bonded body of Example 2 were evaluated in the same manner as in Example 1. Table 1 shows the results.

[0172] [Example 3]

[0173] A ceramic bonded body of Example 3 was obtained in the same manner as in Example 1 except that the average primary particle size of the aluminum oxide powder contained in the insulating layer was set to 1.9 μm. In the obtained ceramic bonded body, the ratio (R1) of the total thickness t2 of the first intermediate layer and the thickness of the second intermediate layer to the thickness t1 of the conductive layer was 8%.

[0174] The insulation properties of the ceramic joint body of Example 3 were evaluated in the same manner as in Example 1. Table 1 shows the results.

[0175] [Example 4]

[0176] A ceramic bonded body of Example 4 was obtained in the same manner as in Example 1, except that the average primary particle size of the aluminum oxide powder contained in the insulating layer was set to 3.3 μm, and the heat treatment temperature of the laminate including the first ceramic plate, the first intermediate layer coating film, the conductive layer coating film, the insulating layer coating film, the second intermediate layer coating film, and the second ceramic plate was set to 1750° C. In the obtained ceramic bonded body, the ratio (R1) of the total thickness t2 of the first intermediate layer and the thickness of the second intermediate layer to the thickness t1 of the conductive layer was 8%.

[0177] The insulation properties of the ceramic bonded body of Example 4 were evaluated in the same manner as in Example 1. Table 1 shows the results.

[0178] [Example 5]

[0179] A ceramic bonded body of Example 5 was obtained in the same manner as in Example 1, except that the average primary particle size of the aluminum oxide powder contained in the insulating layer was set to 5.8 μm, and the heat treatment temperature of the laminate including the first ceramic plate, the first intermediate layer coating film, the conductive layer coating film, the insulating layer coating film, the second intermediate layer coating film, and the second ceramic plate was set to 1800° C. In the obtained ceramic bonded body, the ratio (R1) of the total thickness t2 of the first intermediate layer and the thickness of the second intermediate layer to the thickness t1 of the conductive layer was 13%.

[0180] The insulation properties of the ceramic bonded body of Example 5 were evaluated in the same manner as in Example 1. Table 1 shows the results.

[0181] [Comparative Example]

[0182] A ceramic bonded body of Comparative Example was obtained in the same manner as in Example 1 except that the first intermediate layer and the second intermediate layer were not provided and the average primary particle size of the aluminum oxide powder contained in the insulating layer was changed to 1.5 μm.

[0183] The insulation properties of the ceramic bonded body of the comparative example were evaluated in the same manner as in Example 1. Table 1 shows the results.

[0184] [Table 1]

[0185]

[0186] From the results in Table 1, it can be seen that the dielectric withstand voltage of the ceramic bonded body of the comparative example without the intermediate layer is low, but the dielectric withstand voltage of the ceramic bonded bodies of Examples 1 to 5 having the intermediate layer is high. In addition, the larger the average primary particle size of the alumina powder used in the insulating layer, the higher the insulation resistance (comparison between Examples 1 and 2, and comparison between Examples 3 and 4). This is believed to be because the grain boundary phase with low insulation is reduced by coarsening the alumina particles.

[0187] Industrial Applicability

[0188] The present invention provides a ceramic bonded body, an electrostatic chuck device and a method for manufacturing the ceramic bonded body which suppress the occurrence of insulation breakdown (discharge) at the bonding interface between a ceramic plate and a conductive layer.

[0189] The ceramic bonded body of the present invention is a bonded body that has an intermediate layer between the ceramic plate and the conductive layer and in contact with the ceramic plate and the conductive layer, and suppresses the generation of insulation breakdown (discharge) at the bonding interface between the ceramic plate and the conductive layer. Therefore, the ceramic bonded body of the present invention can be appropriately used in an electrostatic chuck component of an electrostatic chuck device, and its usefulness is very large.

[0190] Description of symbols

[0191] 1.10-ceramic joint

[0192] 2-Ceramic plate (1st ceramic plate)

[0193] 2a- One surface of the first ceramic plate

[0194] 3-Ceramic plate (second ceramic plate)

[0195] 3a- One side of the second ceramic plate

[0196] 4- Conductive layer

[0197] 4a- One side of the conductive layer

[0198] 5-Insulation layer

[0199] 5a- One side of the insulation layer

[0200] 6-Middle layer (1st middle layer)

[0201] 6a-One side of the first intermediate layer

[0202] 7-Middle layer (2nd middle layer)

[0203] 100-Electrostatic chuck device

[0204] 102-Electrostatic chuck parts

[0205] 103- Temperature adjustment base member (cooling base member)

[0206] 103a- One main surface of the cooling base

[0207] 104- Adhesive layer

[0208] 111-Loading plate

[0209] 111a- Loading surface of the loading plate

[0210] 112-Support plate

[0211] 113-Electrode for electrostatic adsorption

[0212] 114-Insulation material

[0213] 115-Fixing hole

[0214] 116-Power supply terminal

[0215] 117-Conductive adhesive layer

[0216] 118-Through hole

[0217] 121-Flow path

[0218] 122-High frequency power supply

[0219] 123-Insulation Materials

[0220] 124-DC power supply

Claims

1. A ceramic joint body comprising: a pair of ceramic plates containing a conductive substance; a conductive layer and an insulating layer, disposed between the pair of ceramic plates; and a pair of intermediate layers, interposed between the pair of ceramic plates and the conductive layer and in contact with the pair of ceramic plates and the conductive layer, The conductive layer has any one or more functions of a plasma generating electrode, an electrostatic chuck electrode, and a heater electrode. The insulating layer is provided in the outer edge region other than the portion where the conductive layer is formed, and is bonded to the pair of ceramic plates. The intermediate layer is made of insulating material. When the thickness of the conductive layer is t1 and the total thickness of the intermediate layer is t2, the thickness ratio R1 of the intermediate layer defined by the following formula (1) is 3% or more and 50% or less. R1 = t2 / t1 × 100 (%) (1).

2. The ceramic bonded body according to claim 1, in, The conductive layer is composed of a conductive material and an insulating material, and the insulating layer is composed of an insulating material.

3. The ceramic bonded body according to claim 2, in, The insulating material constituting the insulating layer has an average primary particle size of 1.6 μm or more and 10.0 μm or less.

4. The ceramic bonded body according to claim 1, in, The ceramic plate is composed of a composite of aluminum oxide and silicon carbide.

5. The ceramic bonded body according to claim 2, in, The insulating material contained in the conductive layer, the insulating layer, and the intermediate layer is composed only of aluminum oxide.

6. The ceramic bonded body according to claim 2, in, The conductive material contained in the conductive layer is selected from Mo 2 At least one selected from the group consisting of C, Mo, WC, W, TaC, Ta, SiC, carbon black, carbon nanotubes, and carbon nanofibers.

7. The ceramic bonded body according to claim 1, in, The insulating layer is arranged on the periphery of the conductive layer. The ceramic plate is composed of a composite of aluminum oxide and silicon carbide. The conductive layer is composed of aluminum oxide and molybdenum carbide. The insulating layer is made of aluminum oxide. The intermediate layer is composed of aluminum oxide.

8. An electrostatic chuck device, which is formed by bonding an electrostatic chuck component formed of ceramic and a temperature adjustment base component formed of metal via an adhesive layer, wherein: The electrostatic chuck component is composed of the ceramic bonded body according to any one of claims 1 to 7.

9. A method for producing a ceramic bonded body, the method for producing a ceramic bonded body according to any one of claims 1 to 7, comprising: A step of preparing a first ceramic plate containing a conductive material and a second ceramic plate containing a conductive material; A step of applying an intermediate layer forming paste on one surface of the first ceramic plate to form a first intermediate layer coating film; A step of applying a conductive layer forming paste on a surface of the first intermediate layer coating film opposite to a surface in contact with the first ceramic plate to form a conductive layer coating film; A step of applying an intermediate layer forming paste on a surface of the conductive layer coating film opposite to a surface in contact with the first intermediate layer coating film to form a second intermediate layer coating film; a step of laminating the second ceramic plate on a surface of the second intermediate layer coating film opposite to a surface in contact with the conductive layer coating film; and A step of pressing a laminate including the first ceramic plate, the first intermediate coating film, the conductive coating film, the second intermediate coating film, and the second ceramic plate in a thickness direction while heating the laminate.

10. The method for producing a ceramic joint body according to claim 9, in, Between the step of forming the conductive layer coating film and the step of forming the second intermediate layer coating film, a step of applying an insulating layer forming paste on the surface of the first intermediate layer coating film to form an insulating layer coating film in parallel with the conductive layer coating film is performed.

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