Electrode embedding member and substrate holding member

Abstract

To provide an electrode embedded member, a method for manufacturing the same, and a substrate holding member capable of simultaneously solving pressure uniformity and ease of manufacture.SOLUTION: An electrode embedded member includes a flat plate-shaped substrate made of a ceramic sintered body and having a mounting surface on one main surface, and an electrode embedded in the substrate. The substrate includes inside a gas groove formed in at least two layers parallel to the mounting surface, a communication hole that communicates with the gas grooves of adjacent layers, a plurality of discharge holes for discharging gas to the outside from a first layer gas groove closest to the mounting surface, and a supply hole for supplying gas from the outside to a second layer gas groove farthest from the mounting surface, and in the first layer gas groove, the shortest distance passing through the gas groove from each of the discharge holes to the nearest communication hole along the first layer gas groove has an approximately identical transit shape.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electrode-embedded member and a substrate-holding member. [Background technology]

[0002] In a film forming process such as CVD used in a semiconductor manufacturing process, inert gas is purged to prevent deposition of corrosive gas on the outer edge of the substrate and to suppress corrosion of the mounting table that supports the substrate, and since gas is particularly likely to remain in the gap between the substrate and the substrate mounting table, a purge gas is flowed around the outer periphery of the substrate. In this case, a purge groove and a plurality of through holes are provided in the purge groove at a position corresponding to the outer edge of the substrate on the substrate mounting surface. The plurality of through holes are distributed by a distribution groove provided inside the base, and are connected to the distribution groove via a through hole provided in a shaft joined to the base.

[0003] When the purge gas is made to flow so as to be sprayed into the chamber from the periphery of the substrate (wafer), particularly in the case of a heater with a shaft in which the heater plate is supported by a shaft, the gas is supplied to the heater plate through a centralized gas supply path (vertical hole or piping in the shaft), and a layer is provided in the heater plate with grooves that branch out to the periphery, and the purge gas is made to flow from the periphery of the layer in which the grooves are formed (see Patent Document 1).

[0004] Patent Document 2 discloses a method for manufacturing a support member, in which a ring-shaped gap is formed between a susceptor and a flat portion by an inner peripheral protrusion and an outer peripheral protrusion, and the gap serves as a gas supply path for flowing a backside gas or a purge gas, and includes a step of solid-state bonding to the back surface of the susceptor. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2009-256789 A [Patent Document 2] Patent No. 4386606 Summary of the Invention [Problem to be solved by the invention]

[0006] It was thought that the gas flow rate from the gas outlets on the periphery of the heater would be uniform by designing the gas grooves symmetrically on one plane. However, even if designed as in Patent Document 1, in reality, the heater is dotted with areas that need to be avoided, such as lift pins, various electrode terminals, and thermocouples, so there were limitations to arranging the groove pattern to be completely symmetrical.

[0007] Even if the grooves could be arranged symmetrically, the purge gas flow rate at each gas outlet would vary due to variations in the groove dimensions during manufacturing and the relationship between the positions of the electrodes and grooves inside the heater plate, resulting in non-uniformity in the process.

[0008] In addition, as in Patent Document 2, by providing a large internal space, the gas pressure is uniformed and the gas flow rate is expected to be stable, but when this is used at high temperatures such as in a heater, the large internal space becomes an obstacle to heat transfer. Also, the large internal space makes bonding difficult and the structure is prone to bonding failure.

[0009] In addition, in heaters with a shaft, it is often difficult to provide the gas inlet of the heater plate in the center, as the gas piping must be provided on the inner wall of the shaft, etc. Therefore, there has been a demand for a heater with a shaft that further suppresses the variation in the purge gas flow rate, even in cases where it is not possible to provide a completely symmetrical arrangement from the gas inlet to the gas outlet on the shaft.

[0010] The present invention has been made in consideration of the above circumstances, and has an object to provide an electrode-embedded member, a manufacturing method thereof, and a substrate holding member that can simultaneously achieve both pressure uniformity and ease of manufacture. [Means for solving the problem]

[0011] (1) In order to achieve the above object, the present invention provides an electrode-embedded member, comprising: a flat-plate-shaped base made of a sintered ceramic body and having a mounting surface on one of its main surfaces; and an electrode embedded in the base, wherein the base has gas grooves formed therein in at least two layers parallel to the mounting surface, communication holes connecting the gas grooves in adjacent layers, a plurality of exhaust holes for exhausting gas to the outside from a first-layer gas groove closest to the mounting surface, and supply holes for supplying gas from the outside to a second-layer gas groove farthest from the mounting surface, upper ends of the first gas groove and the second gas groove in a vertical direction perpendicular to the main surface are located below the placement surface in the vertical direction; The first layer gas grooves are characterized in that the route shapes of the first layer gas grooves for the shortest distances passing through the gas grooves from the respective exhaust holes along the first layer gas grooves to the nearest communication hole are each formed to be approximately the same.

[0012] In this way, by forming the gas grooves in multiple layers, the first layer gas grooves can be arranged at a position where various components of the electrode-embedded member (lift pins, electrode terminals, thermocouples, etc.) do not need to be taken into consideration, and the route shape of the gas groove for each exhaust hole can be made approximately the same. As a result, the gas pressure can be made uniform, and the gas can be uniformly exhausted from each exhaust hole. This can improve the film formation distribution, for example, in a film formation process using the electrode-embedded member.

[0013] (2) In the electrode-embedded member of the present invention, the second-layer gas grooves may include a plurality of the communication holes, and the second-layer gas grooves may be formed in an axisymmetrical shape.

[0014] This allows the gas pressure to be adjusted uniformly in the second layer as well, making it possible to more uniformly exhaust gas from each exhaust hole.

[0015] (3) In the electrode-embedding member of the present invention, the gas outlet of the exhaust hole is provided on the mounting surface.

[0016] This makes it possible to efficiently purge gas remaining between the mounting surface and the rear surface of the substrate, thereby making it possible to suppress adhesion of particles to the rear surface of the substrate.

[0017] (4) In the electrode-embedded member of the present invention, the first layer gas groove or the second layer gas groove includes a circumferential groove.

[0018] This allows the gas pressure in the layer in which the circumferential gas grooves are formed to be adjusted more uniformly, so that the gas can be more uniformly discharged from each exhaust hole. Note that both the first layer gas grooves and the second layer gas grooves may include circumferential gas grooves.

[0019] (5) Furthermore, a substrate holding member of the present invention comprises an electrode-embedded member according to any one of (1) to (4) above, and a support member made of a ceramic sintered body and supporting the electrode-embedded member, wherein the support member has a through hole extending from one end face to the other end face, and the through hole is connected to the supply hole.

[0020] This makes it possible to make the gas pressure uniform even in a substrate holding member with a shaft, and to exhaust the gas uniformly from each exhaust hole, which makes it possible to improve the distribution of film formation, for example, in a film formation process using the substrate holding member. Effect of the Invention

[0021] According to the electrode-embedded member and substrate-holding member of the present invention, it is possible to simultaneously achieve both pressure uniformity and ease of manufacture. [Brief description of the drawings]

[0022] [Figure 1] 1 is a schematic cross-sectional view showing an example of an electrode-embedded member according to an embodiment of the present invention. [Diagram 2] 3A and 3B are schematic diagrams showing examples of the shapes of first-layer gas grooves and second-layer gas grooves of an electrode-buried member according to an embodiment of the present invention, respectively. [Diagram 3] 10A and 10B are schematic cross-sectional views showing modified examples of an electrode-embedded member according to an embodiment of the present invention. [Figure 4] 11 is a schematic plan view showing a modified example of an electrode-embedded member according to an embodiment of the present invention. FIG. [Diagram 5] 5A and 5B are schematic diagrams showing modified shapes of a first-layer gas groove and a second-layer gas groove of an electrode-buried member according to an embodiment of the present invention. [Figure 6] 6A to 6C are schematic diagrams showing modified shapes of first-layer gas grooves of an electrode-embedded member according to an embodiment of the present invention. [Figure 7] 1 is a schematic cross-sectional view showing an example of a substrate holding member according to an embodiment of the present invention. [Figure 8] 10A and 10B are schematic cross-sectional views showing modified examples of a substrate holding member according to an embodiment of the present invention. [Figure 9] 4 is a flowchart showing an example of a method for manufacturing an electrode-embedded member according to an embodiment of the present invention. [Figure 10] 3A to 3C are cross-sectional views each showing a schematic diagram of a step in a manufacturing process of an electrode-embedded member according to an embodiment of the present invention. [Figure 11] 3A to 3C are cross-sectional views each showing a schematic diagram of a step in a manufacturing process of an electrode-embedded member according to an embodiment of the present invention. [Figure 12] 3A to 3C are cross-sectional views each showing a schematic diagram of a step in a manufacturing process of an electrode-embedded member according to an embodiment of the present invention. [Figure 13] 3A and 3D are schematic plan views of a plurality of ceramic sintered bodies used in the manufacture of an electrode-embedded member according to an embodiment of the present invention. [Figure 14] 3(a) to 3(c) are cross-sectional views each showing a schematic diagram of one stage in a manufacturing process of an electrode-embedded member according to an embodiment of the present invention. [Figure 15] 4 is a flowchart illustrating an example of a method for manufacturing a substrate holding member according to an embodiment of the present invention. [Figure 16] 1(a) to 1(c) are cross-sectional views each showing a schematic diagram of one stage in a manufacturing process of a substrate holding member according to an embodiment of the present invention. [Figure 17] FIG. 13 is a schematic diagram showing a gas groove of a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Next, an embodiment of the present invention will be described with reference to the drawings. In order to facilitate understanding of the description, the same reference numerals are used for the same components in each drawing, and duplicated descriptions will be omitted. In the configuration diagrams, the size of each component is conceptually shown, and does not necessarily represent the actual dimensional ratio.

[0024] [Embodiment] [Configuration of electrode embedding material] First, the configuration of an electrode-embedded member according to an embodiment of the present invention will be described. FIG. 1 is a schematic cross-sectional view showing an example of an electrode-embedded member according to an embodiment of the present invention. Also, FIGS. 2(a) and 2(b) are schematic views showing an example of the shape of a first-layer gas groove and a second-layer gas groove of an electrode-embedded member according to an embodiment of the present invention, respectively. An electrode-embedded member 100 according to an embodiment of the present invention includes a base body 110 and an electrode 130. The electrode-embedded member 100 is applied to a heater, an electrostatic chuck, and the like.

[0025] The base 110 is made of a ceramic sintered body, formed in a flat plate shape, and has a mounting surface 112 on one of its main surfaces for mounting a substrate. Various materials can be used for the base 110 depending on the application. For example, AlN, Al 2 O 3 , Si 3 N 4 , SiC, etc. The shape of the base 110 can be various shapes such as a disk shape, a polygonal plate shape, an elliptical plate shape, etc., but a disk shape is preferable.

[0026] The base 110 has gas grooves 120 formed in at least two layers parallel to the mounting surface 112, communication holes 114 connecting the gas grooves 120 in adjacent layers, a plurality of exhaust holes 116 for exhausting gas from the first-layer gas groove 121 closest to the mounting surface 112 to the outside, and supply holes 118 for supplying gas from the outside to the second-layer gas groove 122 farthest from the mounting surface 112. The gas grooves 120 formed parallel to the mounting surface 112 may have three or more layers, and in that case, the gas groove 120 closest to the mounting surface 112 is referred to as the first-layer gas groove 121, and the gas groove 120 farthest from the mounting surface 112 is referred to as the second-layer gas groove 122.

[0027] In this way, by forming the gas grooves 120 in multiple layers, the first layer gas groove 121 can be arranged at a position where various components of the electrode-embedded member 100 (lift pins, electrode terminals, thermocouples, gas flow paths in the case of vacuum adsorption, etc.) do not need to be considered. Furthermore, if an attempt is made to avoid the various components of the electrode-embedded member 100 with a single layer of gas grooves, the length of the gas grooves formed in that layer will be long and the bonding area with other layers will be small, making bonding defects more likely to occur. By disposing the gas grooves in multiple layers as in the present invention, the length of the gas grooves in each layer can be shortened, and bonding defects can be suppressed.

[0028] The gas groove 120 may have various shapes in cross section, but considering the smooth flow of gas, a circular shape, an elliptical shape, a rectangular shape, a semicircular shape, or a semi-elliptical shape is preferable, and considering ease of fabrication, a rectangular shape, a semicircular shape, or a semi-elliptical shape is more preferable. The size of the cross section of the gas groove 120 is preferably a width of 1 mm or more and 10 mm or less. Also, it is preferable that the depth is 1 mm or more and 10 mm or less.

[0029] It is preferable that the first-layer gas grooves 121 are formed so that the route shapes of the first-layer gas grooves 121 for the shortest distance passing through the gas grooves 120 from each exhaust hole 116 to the nearest communication hole 114 along the first-layer gas grooves 121 are substantially identical to each other. In this way, by making the route shapes of the gas grooves 120 for each exhaust hole 116 substantially identical, the gas pressure can be made uniform, and the gas can be uniformly exhausted from each exhaust hole 116. This makes it possible to improve the film formation distribution, for example, in a film formation process using the electrode-embedded member 100.

[0030] In addition, the phrase "the route shapes of gas grooves 120 are approximately the same" means that when the route of gas groove 120 taking the shortest distance from each exhaust hole 116 to the nearest communication hole 114 is divided into portions, the shape, size, and connection angle of each portion with adjacent portions can be regarded as being the same for each exhaust hole 116, except for unavoidable errors that arise in the manufacturing process, etc.

[0031] For example, the first-layer gas grooves 121 shown in FIG. 2(a) are connected to four communication holes 114 by the same shape of the first-layer gas grooves 121 having branches, and gas is discharged from eight exhaust holes 116. According to the example shown in FIG. 2(a), when the path of the gas grooves 120 passing through the shortest distance from each exhaust hole 116 to the nearest communication hole 114 is divided into parts, the shape, size, and connection angle of the adjacent parts of each part can be considered to be the same for each exhaust hole 116. That is, the first-layer gas grooves 121 shown in FIG. 2(a) are formed such that the first-layer gas grooves 121 passing through the gas grooves 120 for the shortest distance from each exhaust hole 116 to the nearest communication hole 114 along the first-layer gas grooves 121 are formed to have substantially the same shape. The first-layer gas grooves 121 may be formed in line symmetry or point symmetry.

[0032] The second-layer gas grooves 122 preferably have a plurality of communication holes 114 and are formed in an axisymmetric shape. This allows the gas pressure to be adjusted uniformly in the second layer as well, allowing gas to be discharged more uniformly from each discharge hole 116.

[0033] For example, the second-layer gas groove 122 shown in FIG. 2(b) is provided with four communication holes 114 and one supply hole 118, and is formed in a line-symmetric shape.

[0034] Fig. 3 is a schematic cross-sectional view showing a modified example of an electrode-embedded member according to an embodiment of the present invention. Fig. 4 is a schematic plan view showing a modified example of an electrode-embedded member according to an embodiment of the present invention. Figs. 5(a) and 5(b) are schematic views showing modified shapes of the first-layer gas groove and the second-layer gas groove of the electrode-embedded member according to an embodiment of the present invention, respectively.

[0035] 3 and 4, the gas outlet of the exhaust hole 116 is preferably provided on the mounting surface 112. This makes it possible to efficiently purge gas remaining between the mounting surface 112 and the rear surface of the substrate, and to suppress particle adhesion to the rear surface of the substrate.

[0036] FIG. 6 is a schematic diagram showing a modified example of the shape of the first-layer gas groove of the electrode-embedded member according to the embodiment of the present invention. As shown in FIG. 2(b), FIG. 5(b), and FIG. 6, the first-layer gas groove 121 or the second-layer gas groove 122 preferably includes a circumferential groove. This allows the gas pressure in the layer in which the circumferential gas groove is formed to be adjusted to be more uniform, so that the gas can be more uniformly discharged from each exhaust hole 116. The gas grooves 120 of both the first-layer gas groove 121 and the second-layer gas groove 122 may include a circumferential groove. Note that the second-layer gas grooves 122 in FIG. 2(b) and FIG. 5(b) each show an example in which a circumferential groove is included, but the second-layer gas groove 122 is not limited to one that includes a circumferential groove.

[0037] The multiple exhaust holes 116 are preferably evenly arranged in the base 110. The number of exhaust holes 116 is preferably eight or more. This allows the gas to be purged evenly.

[0038] It is preferable that the first-layer gas grooves 121 are configured by integrating gas grooves that can be integrated. That is, it is preferable that the number of communication holes 114 that communicate the first-layer gas grooves 121 with the gas grooves 120 in the layer immediately below it is smaller than the number of exhaust holes 116. In other words, it is preferable that the first-layer gas grooves 121 have branches. This makes it easier to configure the first-layer gas grooves 121 with approximately the same route shape while avoiding various components of the electrode-embedded member 100. In addition, the effect of the gas grooves 120 on the inhibition of heat conduction can be reduced.

[0039] The electrode 130 is embedded inside the base 110. The electrode 130 may have various shapes, such as a mesh shape or a foil shape, and may be made of various materials, such as molybdenum and tungsten. The electrode 130 may be a heater electrode, an electrostatic attraction electrode, an RF electrode, or the like.

[0040] 1, the electrode 130 is embedded in the upper part of the first-layer gas groove 121, but the embedding position of the electrode 130 is not limited thereto. That is, the electrode 130 may be embedded in a layer between the first-layer gas groove 121 and the second-layer gas groove 122, or may be embedded in a lower part of the second-layer gas groove 122. Furthermore, the electrode 130 may be embedded in the same layer as the gas groove 120, if the shape of the electrode 130 and the shape of the gas groove 120 and other conditions are met.

[0041] The base 110 may include a plurality of electrodes 130. For example, by including a heater electrode and an electrostatic attraction electrode, the electrode-embedded member 100 can be used as a heater-equipped electrostatic chuck. When the base 110 includes a plurality of electrodes 130, the electrodes 130 can be embedded in various positions depending on the design and the like.

[0042] In addition to the above, the electrode-embedding member 100 also includes a necessary terminal 140 and a terminal hole 142. This allows power to be supplied to the electrode .

[0043] The electrode-embedded member of the present invention can simultaneously achieve both the requirements for pressure uniformity and ease of manufacture.

[0044] [Configuration of the substrate holding member] 7 is a schematic cross-sectional view showing an example of a substrate holding member according to an embodiment of the present invention. The substrate holding member 200 according to an embodiment of the present invention includes the electrode-embedded member 100 according to an embodiment of the present invention and a support member 210.

[0045] The support member 210 is joined to the lower surface of the base 110 facing the mounting surface 112, and supports the electrode-embedded member 100. The support member 210 has a through hole 216 that penetrates from one end surface 212 to the other end surface 214, and the through hole 216 communicates with the supply hole 118. This allows gas to be supplied to the supply hole 118 from the through hole 216 that passes through the support member 210. The support member 210 is preferably formed in a cylindrical shape.

[0046] 8 is a schematic cross-sectional view showing a modified example of the substrate holding member according to the embodiment of the present invention. The substrate holding member 200 may be provided with the second-layer gas grooves 122 on the upper side, lower side, or both sides of the interface between the electrode embedding member 100 and the support member 210. In this way, the number of parts required for manufacturing the electrode embedding member 100 can be reduced, and the manufacturing cost can be reduced. In this case, the support member 210 may be a bottomed open cylindrical member with the second-layer gas grooves 122 provided between the bottom and the electrode embedding member 100, or may be a cylindrical member with the second-layer gas grooves 122 provided between the joint surface and the electrode embedding member 100.

[0047] In the substrate holding member 200, the second layer gas grooves 122 are preferably located inside the outer diameter of the support member 210. This makes it possible to suppress heat transfer between the electrode-embedded member 100 and the support member 210.

[0048] The substrate holding member of the present invention can simultaneously achieve both pressure uniformity and ease of manufacture. In addition, since the substrate holding member is joined to the electrode-embedded member and the support member, heat transfer occurs between the electrode-embedded member and the support member. Since the electrode-embedded member of the present invention allows for more flexible design of the position and shape of gas grooves, etc., the position and shape of gas grooves, etc. in the substrate holding member can be determined in consideration of heat transfer between the electrode-embedded member and the support member.

[0049] [Method of manufacturing electrode-embedded members] Next, a method for manufacturing an electrode-embedded member according to an embodiment of the present invention will be described. FIG. 9 is a flow chart showing an example of a method for manufacturing an electrode-embedded member according to an embodiment of the present invention. As shown in FIG. 9, the method for manufacturing an electrode-embedded member according to an embodiment of the present invention includes a sintered body preparation step STEP 1, a gas groove processing step STEP 2, and a sintered body joining step STEP 3. Note that, although a manufacturing method using a molded body hot pressing method in which molded bodies are stacked as described in Japanese Patent No. 6148845 will be described below, a powder hot pressing method in which powdered raw material and electrodes packed in a mold are hot-pressed and sintered may also be used, and the present invention may be replaced with any method as long as it is a method capable of forming gas grooves in an appropriate shape for two or more layers.

[0050] Fig. 10, Fig. 11, and Fig. 12 are cross-sectional views each showing a schematic step in a manufacturing process of an electrode-embedded member according to an embodiment of the present invention. Fig. 13(a) and (b) are schematic plan views of a plurality of ceramic sintered bodies 42 and 43 used in manufacturing an electrode-embedded member according to an embodiment of the present invention. Fig. 14(a) to (c) are cross-sectional views each showing a schematic step in a manufacturing process of an electrode-embedded member according to an embodiment of the present invention. Fig. 10 to Fig. 14 show the case of manufacturing the electrode-embedded member of Fig. 1.

[0051] In the sintered body preparation step STEP 1, a plurality of ceramic molded bodies 11, 12, 13, and 14 are formed from ceramic raw material powder, and necessary processing such as degreasing and processing of recesses is performed. In FIG. 10, the ceramic molded body is divided into four parts, but it may be three or five or more parts depending on the design. For example, additives such as binders, plasticizers, and dispersants are appropriately added to the ceramic raw material powder and mixed to prepare a slurry, which is then granulated by a spray-drying method or the like to produce granules (ceramic raw material powder), which are then pressure-molded to form a plurality of ceramic molded bodies 11, 12, 13, and 14. Powder serving as a sintering aid may be added to the ceramic raw material powder as necessary.

[0052] The ceramic raw material powder is preferably of high purity, preferably 96% or more, more preferably 98% or more, and preferably has an average particle size of 0.1 μm or more and 1.0 μm or less.

[0053] The mixing method may be either wet or dry, and a mixer such as a ball mill or a vibration mill may be used. As a molding method, a known method such as uniaxial pressing or cold isostatic pressing (CIP) may be used. The method of forming the ceramic molded body is not limited to pressing, and may be, for example, green sheet lamination or casting, which may be appropriately degreased or further calcined to produce the ceramic molded body. After molding, the ceramic molded bodies 11, 12, 13, and 14 may be machined to have the shape of the molded body, recesses for accommodating electrodes, recesses for accommodating connecting terminals for connecting electrodes and terminals, grooves, and holes.

[0054] In the degreasing, a plurality of ceramic molded bodies 11, 12, 13, and 14 are degreased at a predetermined temperature or higher for a predetermined time or longer to produce a plurality of ceramic degreased bodies 21, 22, 23, and 24. The ceramic molded bodies 11, 12, 13, and 14 are heat-treated at a temperature of, for example, 400°C or higher and 800°C or lower to become the ceramic degreased bodies 21, 22, 23, and 24, respectively. The degreasing time is preferably 1 hour or higher and 120 hours or lower. For the degreasing, an atmospheric furnace or a nitrogen atmosphere furnace can be used, but an atmospheric furnace is preferable.

[0055] Next, the electrode 130 cut into a predetermined shape is prepared. The electrode 130 may be formed into various shapes, such as a mesh shape or a foil shape. The electrode 130 may be made of various materials, such as molybdenum and tungsten. Although not shown, one or more connecting members to be embedded in the ceramic sintered body may be prepared as necessary. The connecting members are prepared by processing into a shape according to the design of the electrode embedding member 100.

[0056] Next, the prepared electrode 130 and the multiple ceramic degreased bodies 21, 22 are combined into a flat plate to form the ceramic sintered body precursor 30. At this time, if necessary, a connecting member for connecting the terminal 140 to the electrode 130 is also combined and embedded at the same time.

[0057] The formed ceramic sintered body precursor 30 and the plurality of ceramic degreased bodies 23, 24 are then uniaxially pressurized and fired in a direction perpendicular to the main surface to obtain a plurality of ceramic sintered bodies 41, 43, and 44. The pressing force is preferably 1 MPa or more. The firing temperature is preferably 1500°C or more and 2000°C or less. The firing time is preferably 1 hour or more and 12 hours or less. The firing atmosphere is, for example, a nitrogen or inert gas atmosphere, but may also be a vacuum atmosphere. As a result, the ceramic sintered body precursor 30 and the plurality of ceramic degreased bodies 23, 24 are sintered to obtain a plurality of ceramic sintered bodies 41, 43, and 44. The firing may be performed by continuously increasing the temperature.

[0058] In the gas groove processing step STEP 2, for example, as shown in Fig. 13(a), a first-layer gas groove 121 and an exhaust hole 116 are formed on one side (the joint surface with the ceramic sintered body 41) of the ceramic sintered body 43, and a communication hole 114 penetrating the ceramic sintered body 43 is formed. Also, as shown in Fig. 13(b), a second-layer gas groove 122 is formed on one side (the joint surface with the ceramic sintered body 43) of the ceramic sintered body 44, and a supply hole 118 is formed penetrating the ceramic sintered body 44. By combining these, the joint surface of the other ceramic sintered body becomes a lid, and each gas groove 120 (first-layer gas groove 121 and second-layer gas groove 122) is formed inside the ceramic sintered body.

[0059] The gas groove 120 may be formed on the surface of the other ceramic sintered body to be joined, or a part of the gas groove 120 may be formed in each of the two ceramic sintered bodies, and the gas groove 120 may be formed by combining the two. Furthermore, machining of the gas groove 120 etc. may be performed before or after degreasing of the green body, but it is preferable to perform machining after sintering, since the dimensional accuracy is very high when the machining is performed after sintering, and deformation of the gas groove 120 etc. during joining can be suppressed.

[0060] In the sintered body joining step STEP 3, the prepared ceramic sintered bodies, which have been processed with gas grooves and the like as necessary, are combined and heated while being pressurized in a direction perpendicular to the main surface (mounting surface). As a result, a plurality of ceramic sintered bodies 41, 43, and 44 are joined together to obtain an electrode-embedded member 100 having at least two layers of gas grooves 120 therein. The joining can be performed using either a joining method using a joining material or a joining method not using a joining material. This sintered body joining step may include a step of adjusting the joining surfaces of the ceramic sintered bodies 41, 43, and 44 before joining to a predetermined surface roughness and flatness.

[0061] A step may be provided in which a terminal hole 142 is machined in the electrode-embedding member 100 according to the position of the embedded electrode 130 in the joined electrode-embedding member 100 to expose a part of the electrode 130 or the connection member, and a terminal 140 is connected to the exposed electrode 130 or the connection member with brazing material or the like. The terminal 140 may be made of Ni or the like. The brazing material may be an Au-based or Ag-based brazing material. An intermediate member 150 made of Kovar or the like may be disposed between the electrode 130 or the connection member and the terminal 140, and brazing may be performed.

[0062] In this way, it is possible to manufacture an electrode-embedded member that simultaneously satisfies the requirements for pressure uniformity and ease of manufacture.

[0063] In addition, a ceramic calcined body preparation step may be provided in the sintered body preparation step STEP 1. When the ceramic calcined body preparation step is provided, the ceramic degreased body is calcined at a temperature of 1200°C to 1700°C to prepare a ceramic calcined body. The calcination time is preferably 0.5 hours to 12 hours. The calcination atmosphere is preferably a nitrogen or inert gas atmosphere, but may be a vacuum atmosphere. When the calcined body preparation step is provided, the machining to form gas grooves, etc. may be performed after the calcined body preparation step. By performing the machining at this stage, the dimensional accuracy can be improved compared to machining the degreased body, and the machining is easier than machining after sintering.

[0064] [Method of manufacturing the substrate holding member] Next, a method for manufacturing a substrate holding member according to an embodiment of the present invention will be described. Fig. 15 is a flow chart showing an example of a method for manufacturing a substrate holding member according to an embodiment of the present invention. As shown in Fig. 15, the method for manufacturing a substrate holding member according to an embodiment of the present invention includes a sintered body preparation step (STEP 1), a gas groove processing step (STEP 2), a sintered body joining step (STEP 3), a support member preparation step (STEP 4), and a joining step (STEP 5). Steps 1 to 3 are the same as the method for manufacturing the electrode-embedded member 100 described above, so the description will begin with STEP 4.

[0065] 16(a) to 16(c) are cross-sectional views each showing a schematic diagram of a step in the manufacturing process of a substrate holding member according to an embodiment of the present invention, in which the substrate holding member shown in FIG.

[0066] In the support member preparation step STEP 4, the second ceramic molded body 15 is formed from the second ceramic raw material powder. The second ceramic raw material powder preferably contains the same raw material as the ceramic raw material powder of the electrode-embedded member 100 as the main component and does not contain a sintering aid. The second ceramic molded body 15 is degreased at a predetermined temperature or more for a predetermined time or more to produce a second ceramic degreased body 25. The method for producing the second ceramic raw material powder, the method for forming the second ceramic molded body 15, and the numerical range of the degreasing conditions of the second ceramic molded body may be the same as those in the sintered body preparation step STEP 1. The degreasing in the support member preparation step STEP 4 may be performed simultaneously with the degreasing in the sintered body preparation step STEP 1.

[0067] Next, the second ceramic degreased body 25 is fired to fire the support member 210 that supports the electrode-embedded member 100. The firing of the support member 210 is preferably performed at normal pressure. The firing temperature is preferably 1500°C or higher and 2000°C or lower. The firing time is preferably 1 hour or higher and 12 hours or lower. The firing atmosphere is, for example, a nitrogen or inert gas atmosphere, but may also be a vacuum atmosphere.

[0068] Then, a through hole 216 penetrating from one end face 212 to the other end face 214 of the support member 210 is formed at a position communicating with the supply hole 118 of the electrode embedding member 100. The formation of the through hole 216 may be performed after degreasing.

[0069] In the bonding step STEP 5, the support member 210 is bonded to the bonding position of the lower surface of the base 110 of the electrode-embedded member 100. The bonding can be performed using either a bonding method using a bonding material or a bonding method not using a bonding material. This bonding step may include a step of adjusting the lower surface and the bonding surface of the support member 210 before bonding to a predetermined surface roughness and flatness. When the support member 210 is bonded to the electrode-embedded member 100 to form the substrate holding member 200, the processing of the terminal hole 142 of the electrode-embedded member 100 and the brazing of the terminal 140 may be performed after bonding.

[0070] In this way, it is possible to manufacture a substrate holding member 200 that simultaneously satisfies requirements for pressure uniformity and ease of manufacture.

[0071] [Examples and Comparative Examples] Example 1 First, each ceramic sintered body was prepared. 2 O 3 Four compacts were formed using ceramic raw material powder mainly composed of AlN to which sintering aids were added. Recesses for accommodating electrodes and recesses for accommodating connection terminals for connecting electrodes and terminals were machined at predetermined positions. These were degreased and sintered to produce a first ceramic sintered body with a diameter of φ340 mm and a thickness of 2 mm, a second ceramic sintered body with a diameter of φ340 mm and a thickness of 10 mm, and a third ceramic sintered body with a diameter of φ340 mm and a thickness of 10 mm. In addition, one ceramic compact was formed using the second ceramic raw material powder mainly composed of AlN to which no sintering aids were added. This was degreased and sintered to produce a support member with an inner diameter of 50 mm, an outer diameter of 70 mm, a length of 150 mm, and an enlarged diameter portion with an outer diameter of 90 mm and a thickness of 15 mm at the upper and lower ends.

[0072] Each compact was degreased at 550°C for 12 hours in an air atmosphere. The first to third ceramic sintered bodies were sintered by uniaxial hot press sintering at 1800°C for 2 hours at a pressure of 1 MPa in a nitrogen atmosphere. The support member was sintered at 1850°C for 2 hours at normal pressure in a nitrogen atmosphere. The first ceramic sintered body was sintered with an electrode made of molybdenum mesh (wire diameter 0.1 mm, mesh size 50 mesh) with a diameter of 290 mm cut to a specified shape embedded therein.

[0073] Next, grooves and communication holes were processed. The first ceramic sintered body had exhaust holes of Φ5 mm at 8 equal intervals on PCD 280 mm. The second ceramic sintered body had exhaust holes of Φ5 mm at 4 equal intervals on PCD 120 mm. In addition, a first layer gas groove was provided on one side, with a groove width of 5 mm and a groove depth of 5 mm, symmetrically shaped from the end of the exhaust hole toward the outer periphery, as shown in Figure 5 (a). The other end of the first layer gas groove was located at 8 equal intervals on PCD 280 mm on the outer periphery, and was aligned with the position of the exhaust hole of the first ceramic sintered body. The third ceramic sintered body had a circumferential groove with a groove width of 5 mm and a groove depth of 5 mm, with a center line of Φ120 mm. In addition, a groove with a groove width of 5 mm and a groove depth of 5 mm was provided from the circumferential groove to a position communicating with the through hole of the support member. In addition, a supply hole of Φ5 mm was provided at a position communicating with the through hole of the support member. The support member was provided with a through hole of Φ5 mm that penetrated from one end face to the other end face of the support member within the wall of the cylindrical portion of the support member and located 60 mm from the center of the cylindrical portion.

[0074] Next, the first to third ceramic sintered bodies were stacked together while adjusting the grooves and holes so that they were accurately connected, and then uniaxial hot press sintered at 1850°C for 2 hours while applying a force of 10 MPa in the direction perpendicular to the mounting surface. In this manner, the electrode-embedded member was sintered.

[0075] The electrode-embedded member and the support member were then joined by heating at 1700°C for 1 hour while applying a force of 1 MPa in the direction perpendicular to the mounting surface. In addition, the necessary terminal holes were drilled, and Ni terminals were brazed with Au solder. In this manner, the substrate holder of Example 1 was produced.

[0076] Example 2 In Example 2, a substrate holding member was produced under the same conditions and with the same size as Example 1, except that the first-layer gas groove provided in the second ceramic sintered body was shaped to include a circumferential groove as shown in FIG. 6.

[0077] (Comparative Example) In the comparative example, a first ceramic sintered body having a diameter of φ340 mm and a thickness of 12 mm and a second ceramic sintered body having a diameter of φ340 mm and a thickness of 10 mm were prepared. The first ceramic sintered body had exhaust holes of φ5 mm at 8 equally spaced positions with a PCD of 280 mm. The second ceramic sintered body had gas grooves of a groove width of 5 mm and a groove depth of 5 mm as shown in FIG. 17 on one side. In addition, a supply hole of φ5 mm was provided at a position communicating with the through hole of the support member. This was joined to prepare an electrode-embedded member of Comparative Example 1. Then, the same support member as in Example 1 was joined to this to prepare a substrate holding member of Comparative Example 1. FIG. 17 is a schematic diagram showing a gas groove of the comparative example.

[0078] That is, the comparative example is a substrate holding member having one layer of gas grooves. Note that the gas grooves in Fig. 17 are shaped to avoid various components of the electrode-embedded member, but are not shaped in accordance with the positions and shapes of the actual components.

[0079] (Measurement of film distribution) Using the substrate holding members of the examples and the comparative examples, SiO using TEOS raw material at 400°C was 2 The film thickness distribution on the entire substrate was measured using a spectroscopic film thickness meter.

[0080] The substrate holding member of Example 1 had a film formation distribution of 10000±500 nm. The substrate holding member of Example 2 had a film formation distribution of 10000±400 nm. In contrast, the substrate holding member of the comparative example had a film formation distribution of 10000±900 nm. This confirmed that the substrate holding member of the present invention has an improved film formation distribution compared to conventional products by uniformly ejecting purge gas from the exhaust holes.

[0081] From the above, it has been confirmed that the electrode-embedded member and substrate holding member of the present invention can simultaneously achieve both pressure uniformity and ease of manufacture. It has also been confirmed that the manufacturing method of the present invention can manufacture such an electrode-embedded member.

[0082] The present invention is not limited to the above-described embodiment, and it goes without saying that various modifications and equivalents are included within the spirit and scope of the present invention. In addition, the structure, shape, number, position, size, etc. of the components shown in each drawing are for convenience of explanation and may be changed as appropriate. [Explanation of symbols]

[0083] 11, 12, 13, 14 Ceramic molding 21, 22, 23, 24 Ceramic degreased body 30 Ceramic sintered body precursor 30 41, 43, 44 Sintered ceramics 100 Electrode embedding member 110 Base 112 Placement surface 114 Communication hole 116 Discharge hole 118 Supply hole 120 Gas Groove 121 First layer gas groove 122 Second layer gas groove 130 electrodes 140 Terminals 142 Terminal hole 200 Substrate holding member 210 Support member 212 One end face 214 The other end face 216 Through hole

Claims

1. An electrode embedding member, A flat-plate-shaped base body made of a ceramic sintered body and having a mounting surface on one of its main surfaces; an electrode embedded in the substrate; the base has gas grooves formed therein in at least two layers parallel to the mounting surface, communication holes connecting the gas grooves of adjacent layers, a plurality of exhaust holes for exhausting gas from a first-layer gas groove closest to the mounting surface to the outside, and supply holes for supplying gas from the outside to a second-layer gas groove farthest from the mounting surface, upper ends of the first gas groove and the second gas groove in a vertical direction perpendicular to the main surface are located below the mounting surface in the vertical direction; the first layer gas grooves are each formed so that the route shapes of the first layer gas grooves for the shortest distance from the exhaust hole along the first layer gas groove to the nearest communication hole are substantially identical to each other.

2. The second layer gas groove has a plurality of communication holes formed therein, 2. The electrode-embedded member according to claim 1, wherein the second-layer gas groove is formed in an axisymmetric shape.

3. 3. The electrode-embedded member according to claim 1, wherein the gas outlet of the exhaust hole is provided on the placement surface.

4. 4. The electrode-embedded member according to claim 1, wherein the first-layer gas groove or the second-layer gas groove includes a circumferential groove.

5. An electrode-embedded member according to any one of claims 1 to 4, A support member made of a ceramic sintered body and supporting the electrode-embedded member, A substrate holding member, wherein the support member has a through hole penetrating from one end surface to the other end surface, the through hole communicating with the supply hole.

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