JP7836151B2 - Support member, substrate holding member, and method for manufacturing the same - Google Patents

Description

This invention relates to a support member, a substrate holding member, and a method for manufacturing the same.

Heater plates (substrate holding components) with embedded heating resistors have been used as components for semiconductor manufacturing equipment. These heater plates can heat the substrate on which they are placed.

Patent Document 1 discloses a heating device comprising a base body having a heating surface and a heating element inside, and a cylindrical member having lead wires for introducing electric current to the heating element inside and connected to the back surface of the heating surface. The thermal conductivity of the base body is 1.0 to 2.0 times that of the cylindrical member, the thermal conductivity of the base body is 60 to 220 W/m·K, and the thermal conductivity of the cylindrical member is 60 to 200 W/m·K. The base body and the cylindrical member are primarily composed of aluminum nitride. The plate and shaft are joined in a firing furnace by a direct bonding method. According to the technology described in Patent Document 1, it is possible to provide a heating device in which the temperature on the plate surface becomes uniform and cracks do not occur due to temperature differences and differences in thermal expansion coefficients.

Patent Document 2 discloses a support structure for a wafer holder in which an electrical circuit is embedded in a ceramic sintered body, supported by a cylindrical support member. The support structure is characterized in that a flange component with screw threads is attached to the wafer holder, and the screw threads on the cylindrical support member are screwed into the screw threads of the flange component. It states that the difference in thermal expansion coefficients of the wafer holder, flange component, and cylindrical support member is 2.0 × ^10⁻⁶ /K or less, the material of the wafer holder is aluminum nitride, and the material of the flange component and cylindrical support member may be any of aluminum nitride, mullite-alumina composite, silicon carbide, silicon nitride, or alumina. It states that this reduces the generation of particles and prevents damage to the wafer holder, flange component, or cylindrical support member during heating.

Japanese Patent Publication No. 2005-285355 Japanese Patent Publication No. 2008-153413

AlN ceramic heaters with shafts are difficult to manufacture as a single unit (near-net shape) due to their shape. Therefore, the heater plate and shaft are manufactured separately and then joined together. In this process, the plate and shaft are made from a combination of materials, either of the same or different types, depending on the temperature and environment in which the heater will be used. When the heater plate and shaft are made from different materials before joining, uneven stress is likely to occur near the joint surface, particularly due to differences in thermal expansion coefficients. This uneven stress affects the reliability of the heater with shaft after joining. Furthermore, when using a heater with a shaft, heat from the heater plate is conducted through the shaft, and the thermal insulation properties of the shaft affect the symmetry of the temperature distribution on the substrate mounting surface.

Therefore, it was desirable that the shaft-type heater, manufactured by joining the heater plate and shaft sections, be free from stress-related problems after joining, and that the symmetry of the temperature distribution could be adjusted by controlling the thermal insulation properties of the shaft section.

However, while Patent Documents 1 and 2 consider uniform heating of the substrate, they do not consider adjusting the symmetry of the temperature distribution by adjusting the thermal insulation of the shaft portion.

This invention has been made in view of these circumstances, and aims to provide a support member, a substrate holding member, and a method for manufacturing the same, which prevent stress defects after joining and allow for adjustment of the thermal insulation properties of the support member to adjust the symmetry of the temperature distribution of the substrate.

(1) In order to achieve the above objective, the present invention provides a support member for a substrate holding member on which a substrate is placed, the support member having a plate-shaped member having one main surface on which the substrate is placed and another main surface facing the first main surface in a direction perpendicular to it, and a boss located on the other main surface of the plate-shaped member , wherein the support member is formed in a hollow cylindrical shape from a ceramic sintered body mainly composed of AlN, the support member is composed of a first region and a second region aligned in the vertical direction , the second region is a ring-shaped disc joined to the boss and having the same outer diameter as the boss, the first region is a hollow cylindrical member joined to the disc, the thermal conductivity of the first region at 25°C is 100 W/mK or more, and the thermal conductivity of the second region at 25°C is 80 W/mK or less.

In this way, by providing sections of the support member with different thermal conductivity, the thermal insulation properties of the support member (heat flow through the support member) can be adjusted. As a result, the symmetry of the temperature distribution on the mounting surface of the substrate holding member can be adjusted.

(2) Furthermore, the support member of the present invention is characterized in that the Y-component in the first region has a Y _-2O - ₃ equivalent concentration of 0.4 wt% or more and 5 wt% or less, and the Y-component in the second region has a Y _-2O - ₃ equivalent concentration of 0.1 wt% or less.

In this way, by providing sections with different concentrations of Y in the AlN support member, it is possible to create sections with different thermal conductivity. As a result, the thermal insulation properties of the support member can be adjusted through the combined thermal conductivity characteristics.

(3) Furthermore, the support member of the present invention is characterized in that one end of the support member is composed of the first region, and the other end of the support member is composed of the second region.

In this way, by having different thermal conductivity at one end of the support member and the other end, that is, by configuring the portion of the support member with different thermal conductivity characteristics in the vertical direction, the heat flow passing through the support member can be controlled.

(4) The substrate holding member of the present invention is a substrate holding member comprising: a plate-shaped electrode embedding member made of a ceramic sintered body mainly composed of AlN, having an electrode embedded in it, having one main surface on which a substrate is placed and another main surface facing the one main surface perpendicular to it; an electrode embedding member having a cylindrical boss located on the other main surface of the plate-shaped member; and a support member made of a ceramic sintered body mainly composed of AlN, having an enlarged diameter portion provided at the end on the electrode embedding member side and a cylindrical portion with a smaller diameter than the enlarged diameter portion, and supporting the electrode embedding member, wherein the enlarged diameter portion and the cylindrical portion are aligned in the vertical direction, the enlarged diameter portion is joined to the boss, the outer diameter of the enlarged diameter portion is the same as the outer diameter of the boss, the thermal conductivity of the enlarged diameter portion is the same as the thermal conductivity of the boss, the thermal conductivity of the cylindrical portion is different from the thermal conductivity of the enlarged diameter portion, and the thermal conductivity of the cylindrical portion is the same as the thermal conductivity of the plate-shaped member.

Thus, by configuring the thermal conductivity of the end of the enlarged diameter section and the end opposite the enlarged diameter section to differ, that is, by configuring the support member with different thermal conductivity characteristics in the vertical direction, the heat flow passing through the support member can be controlled. As a result, heat transfer between the electrode embedding member and the support member can be adjusted, and the symmetry of the temperature distribution on the substrate mounting surface can be controlled.

(5) Furthermore, the substrate holding member of the present invention is characterized in that the Y-component in the end of the enlarged diameter portion has a Y- _2O - ₃ equivalent concentration of 0.4 wt% or more and 5 wt% or less, and the Y-component in the end facing the enlarged diameter portion has a Y- _2O - ₃ equivalent concentration of 0.1 wt% or less.

Thus, by providing portions with different Y concentrations in the vertical direction of the AlN support member, it is possible to create portions with different thermal conductivity in the vertical direction, thereby actually constructing a substrate holding member in which the heat flow passing through the support member is controlled.

(6) Furthermore, the substrate holding member of the present invention is characterized in that the Y-component concentration of Y _- component contained in the boss of the _electrode embedding member is substantially the same as the Y-component concentration of Y _{- component} contained in the end of the enlarged diameter portion of the support member.

Thus, because the Y-component Y _- O- ₃ equivalent concentration at the end of the enlarged diameter portion of the electrode embedding member and the support member is approximately the same, the bonding strength of the joint surface is stable, resulting in a highly reliable substrate holding member.

(7) Furthermore, the present invention provides a method for manufacturing a substrate holding member, comprising the steps of: forming one or more first ceramic molded bodies from a first ceramic raw material powder mainly composed of AlN and in which the amount of sintering aid added is adjusted; forming one or more second ceramic molded bodies from a second ceramic raw material powder mainly composed of AlN and in which the amount of sintering aid added is adjusted to be less than the amount of sintering aid added to the first ceramic raw material powder, or in which no sintering aid is added; and combining the one or more first ceramic molded bodies and the one or more second ceramic molded bodies to form a support part The process involves forming a material precursor, firing the support member precursor to produce a support member, forming a plurality of third ceramic molded bodies from a third ceramic raw material powder mainly composed of AlN with a predetermined amount of sintering aid added, forming a fourth ceramic molded body from a fourth ceramic raw material powder, degreasing the plurality of third ceramic molded bodies at a predetermined temperature and for a predetermined time to produce a plurality of third degreased ceramic bodies, degreasing the fourth ceramic molded body at a predetermined temperature and for a predetermined time to produce a boss precursor , and preparing electrodes, and the electrodes, the plurality of third ceramics The process involves combining degreased bodies to form an electrode embedding member precursor that is flat in shape, has a mounting surface on one main surface, and has an electrode embedded in it; manufacturing an electrode embedding member by uniaxial pressurizing and firing perpendicular to the main surface of the electrode embedding member precursor with the boss precursor on top of the other main surface; or preparing a bonding material and applying the bonding material to at least one of the end faces to be joined, the boss or the support member of the electrode embedding member, and placing the support member on the boss, and The method includes a step of joining the electrode embedding member and the support member by heating while applying pressure perpendicular to the main surface, wherein the outer diameter of the second ceramic molded body is the same as the outer diameter of the boss and is joined to the boss, the one or more first ceramic molded bodies are aligned perpendicular to the second ceramic molded body, the first region of the support member where the first ceramic molded body is fired has a thermal conductivity of 100 W/mK or more at 25°C, and the second region of the support member where the second ceramic molded body is fired has a thermal conductivity of 80 W/mK or less at 25°C.

This allows for the provision of sections with different thermal conductivity in the support member, thereby adjusting the thermal insulation properties (heat flow through the support member). This, in turn, allows for adjustment of the symmetry of the temperature distribution on the mounting surface of the substrate holding member.

(8) Furthermore, the present invention relates to a method for manufacturing the substrate holding member, comprising the steps of: preparing a first ceramic raw material powder mainly composed of AlN with an adjusted amount of sintering aid added, and a second ceramic raw material powder mainly composed of AlN with an adjusted amount of sintering aid added, or a second ceramic raw material powder with no sintering aid added; forming a support member precursor by placing one of the first ceramic raw material powder or the second ceramic raw material powder into a mold and pre-forming it, and then placing the other into the mold and pre-forming it, repeating this process one or more times; and firing the support member precursor to form a support member The process involves: preparing a third ceramic molded body from a third ceramic raw material powder mainly composed of AlN with a predetermined amount of sintering aid added; forming a fourth ceramic molded body from a fourth ceramic raw material powder; degreasing the plurality of third ceramic molded bodies at a predetermined temperature and for a predetermined time to produce a plurality of third degreased ceramic bodies ; degreasing the fourth ceramic molded body at a predetermined temperature and for a predetermined time to produce a fourth degreased ceramic body; preparing an electrode; and combining the electrode and the plurality of third degreased ceramic bodies to form a flat plate with a mounting surface on one of its main surfaces. The process involves forming an electrode embedding member precursor in which an electrode is embedded, forming a cylindrical boss precursor from the fourth degreased ceramic body, manufacturing an electrode embedding member by uniaxial pressure firing perpendicular to the main surface with the boss precursor placed on top of the other main surface of the electrode embedding member precursor, and placing the support member on the boss formed by the boss precursor of the electrode embedding member and heating while applying pressure perpendicular to the main surface, or preparing a bonding material and applying the bonding material to at least one of the end faces of the electrode embedding member to which the boss or the support member is joined , placing the support member on the boss and firing perpendicular to the main surface The method includes a step of joining the electrode embedding member and the support member by heating under pressure, wherein the molded body of the second ceramic raw material powder is a ring-shaped disc having the same outer diameter as the boss and is joined to the boss, the molded body of the first ceramic raw material powder is aligned perpendicularly to the molded body of the second ceramic raw material powder, the first region of the support member where the molded body of the first ceramic raw material powder is fired has a thermal conductivity of 100 W/mK or more at 25°C, and the second region of the support member where the molded body of the second ceramic raw material powder is fired has a thermal conductivity of 80 W/mK or less at 25°C.

This allows for the provision of sections with different thermal conductivity in the support member, thereby adjusting the thermal insulation properties (heat flow through the support member). This, in turn, allows for adjustment of the symmetry of the temperature distribution on the mounting surface of the substrate holding member.

According to the present invention, the thermal insulation properties of the support member can be adjusted, and the symmetry of the temperature distribution on the mounting surface of the substrate holding member can be adjusted.

This is a schematic cross-sectional view showing an example of a support member according to an embodiment of the present invention. (a) to (f) are schematic cross-sectional views showing modified examples of the support member according to the present invention. This is a schematic cross-sectional view showing an example of a substrate holding member according to an embodiment of the present invention. This is a schematic cross-sectional view showing a modified example of a substrate holding member according to an embodiment of the present invention. This flowchart shows an example of a method for manufacturing a substrate holding member according to an embodiment of the present invention. (a) to (c) are schematic cross-sectional views illustrating a step in the manufacturing process of a support member according to an embodiment of the present invention. (a) to (c) are schematic cross-sectional views illustrating a different stage in the manufacturing process of a support member according to an embodiment of the present invention. (a) to (d) are schematic cross-sectional views illustrating a step in the manufacturing process of a substrate holding member according to an embodiment of the present invention. (a) and (b) are schematic cross-sectional views illustrating a step in the manufacturing process of a substrate holding member according to an embodiment of the present invention.

Next, embodiments of the present invention will be described with reference to the drawings. To facilitate understanding of the explanation, the same reference numeral is used for identical components in each drawing, and redundant explanations are omitted. Note that the sizes of each component in the configuration diagrams are conceptual representations and do not necessarily represent actual dimensional ratios.

[Embodiment]
[Structure of the support members]
First, the configuration of the support member according to an embodiment of the present invention will be described. Figure 1 is a schematic cross-sectional view showing an example of a support member according to an embodiment of the present invention. The support member 100 according to an embodiment of the present invention is formed in a cylindrical shape from a ceramic sintered body mainly composed of AlN. "Mainly composed of AlN" means that the ceramic sintered body contains 90 wt% or more of AlN.

The support member 100 is composed of a first region 101 and a second region 102. The thermal conductivity of the first region 101 at 25°C is 100 W/mK or higher, and the thermal conductivity of the second region 102 at 25°C is 80 W/mK or lower. By providing the support member 100 with portions having different thermal conductivity, the thermal insulation properties (heat flow through the support member 100) can be adjusted. As a result, the symmetry of the temperature distribution on the mounting surface of the substrate holding member can be adjusted. The symmetry of the temperature distribution on the mounting surface of the substrate holding member refers to a predetermined temperature gradient from the center of the mounting surface towards the outer periphery.

Figures 2(a) to 2(f) are schematic cross-sectional views showing modified examples of the support member according to the embodiment of the present invention. The shape of the support member 100 and the position of the boundary between the first region 101 and the second region 102 constituting the support member 100 can vary, as shown in Figures 2(a) to 2(f), etc. The first region 101 may consist only of the enlarged diameter portion, or it may extend partway up the cylindrical portion. Furthermore, there may be no enlarged diameter portion, or there may be no flange portion on the side facing the enlarged diameter portion. Also, the enlarged diameter portion may be formed in both the first region 101 and the second region 102, or there may be a step in the enlarged diameter portion. Furthermore, the enlarged diameter portion may be formed in the second region 102, or, although not shown, at least one of the first region 101 or the second region 102 may be formed separately. In this way, by configuring the support member 100 with regions having different thermal conductivity, the thermal insulation properties of the support member 100 can be adjusted. Furthermore, the region constituting the support member 100 can be designed considering both the connection with the electrode embedded member and the thermal conductivity.

The ceramic sintered bodies forming the first region 101 and the second region 102 both have the same main component, AlN, and their shrinkage rates during sintering are similar. Therefore, the different regions can be integrated without distortion, resulting in a strong bond at the interface between the first region 101 and the second region 102. Furthermore, since the thermal expansion coefficients of the first region 101 and the second region 102 are similar when using the substrate holding member equipped with the support member 100, the risk of cracks or other damage occurring at the interface can be reduced even with repeated use.

The Y-component in the first region 101 _{, converted to Y₂O₃ ,} is preferably 0.4 wt% or more and 5 wt% or less. This allows the thermal conductivity of the first region 101 at 25°C to be easily adjusted to 100 W/mK or more when _Y₂O₃ is used as a sintering aid. Furthermore, the Y- _component in the second region 102, converted to _{Y₂O₃ ,} is preferably 0.1 wt% or less. This allows the thermal conductivity of the second region ₁₀₂ at 25°C to be easily adjusted to 80 W/mK or less when _Y₂O₃ is used as a sintering aid. In addition, by providing portions with different Y concentrations in the AlN support member 100 in this way, portions with different thermal conductivity can be easily provided. As a result, the thermal insulation properties of the support member 100 can be adjusted by the combined thermal conductivity characteristics.

_{The Y₂O₃ equivalent} concentration of component Y in the second region 102 being 0.1 wt% or less includes 0 wt%, meaning that component Y is substantially not added. Substantially not added means that component Y is not added as a sintering aid, and if component Y is included as an impurity and its _Y₂O₃ equivalent concentration is less than 10 ppm, _it is considered substantially 0 wt%.

A ceramic sintered body mainly composed of AlN has high thermal conductivity and excellent heat resistance and plasma resistance. _It is known that in the range where the Y component's _Y₂O₃ equivalent concentration is 10 wt% or less, the lower the concentration, the lower the thermal conductivity, so the thermal conductivity can be easily adjusted. Therefore, by forming a first region 101 and a second region 102 using a ceramic sintered body mainly composed of AlN, the thermal conductivity can be adjusted for each region, and a support member 100 with excellent heat resistance and plasma resistance can be constructed.

Preferably, one end of the support member 100 is composed of a first region 101, and the other end of the support member 100 is composed of a second region 102. In this way, by having different thermal conductivity at one end of the support member 100 and the other end, that is, by configuring the portion of the support member 100 with different thermal conductivity characteristics in the vertical direction of the support member 100, the heat flow passing through the support member 100 can be controlled.

The support member of the present invention can adjust the thermal insulation (heat flow through the support member) and the symmetry of the temperature distribution on the mounting surface of the substrate holding member.

[Configuration of substrate holding member]
Next, the configuration of the substrate holding member according to an embodiment of the present invention will be described. Figure 3 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 comprises an electrode embedding member 120 and a support member 100. The substrate holding member 200 of the present invention is applicable to a heater with a shaft, an electrostatic chuck with a shaft, and the like.

The electrode embedding member 120 is made of a ceramic sintered body mainly composed of AlN and is formed in a flat plate shape. "Mainly composed of AlN" means that the ceramic sintered body contains 90 wt% or more of AlN. The electrode embedding member 120 has a mounting surface 122 on one of its main surfaces for placing a substrate. Furthermore, the shape of the electrode embedding member 120 can be various, such as a disc shape, polygonal shape, or elliptical shape.

A ceramic sintered body primarily composed of AlN has high thermal conductivity and excellent heat resistance and plasma resistance. Therefore, by forming the electrode embedding member 120 using a ceramic sintered body primarily composed of AlN, an electrode embedding member 120 with excellent heat resistance and plasma resistance can be constructed.

The electrode embedding member 120 has an electrode 130 embedded inside. The electrode 130 can have various shapes, such as mesh or foil. Furthermore, it can be made from various materials, such as molybdenum or tungsten.

The electrode embedding member 120 may have multiple electrodes 130. For example, by including a heater electrode and an electrostatic adsorption electrode, the substrate holding member 200 can be used as a heater-equipped electrostatic chuck.

The support member 100 is made of a ceramic sintered body mainly composed of AlN, and has an enlarged diameter portion 112 and a cylindrical portion 114 with a smaller diameter than the enlarged diameter portion provided at the end facing the electrode embedding member 120, thereby supporting the electrode embedding member 120. "Mainly composed of AlN" means that the ceramic sintered body contains 90 wt% or more of AlN. In Figure 3, the end portion 116 facing the enlarged diameter portion is also a flange portion with a larger diameter than the cylindrical portion 114, similar to the enlarged diameter portion 112; however, the support member 100 and substrate holding member 200 of the present invention are not limited to this.

The thermal conductivity of the end of the enlarged diameter portion 112 of the support member 100 differs from that of the end 116 facing the enlarged diameter portion. By configuring the support member 100 in a way that the thermal conductivity differs between the end of the enlarged diameter portion 112 and the end 116 facing the enlarged diameter portion—that is, by configuring a portion of the support member 100 with different thermal conductivity characteristics in the vertical direction—the heat flow passing through the support member 100 can be controlled. As a result, heat transfer between the electrode embedding member 120 and the support member 100 can be adjusted, and the symmetry of the temperature distribution on the substrate mounting surface 122 can be adjusted. Note that the end of the enlarged diameter portion refers to a predetermined area of the enlarged diameter portion 112 of the support member 100 on the electrode embedding member 120 side, and may be a part of the electrode embedding member 120 side or the entire enlarged diameter portion 112.

Figure 4 is a schematic cross-sectional view showing a modified example of a substrate holding member according to an embodiment of the present invention. As shown in Figure 4, in the substrate holding member 200, the boss 118 may be joined to the support member 100 during the joining of the electrode embedding member 120 and the support member 100. In this case, although the boss 118 is formed as part of the electrode embedding member 120 during the manufacturing process, in the substrate holding member 200 of the present invention, the boss 118 joined to the support member 100 is considered to be part of the support member 100, i.e., the enlarged diameter portion 112. Therefore, when the boss 118 is formed, the thermal conductivity of the boss 118 is equal to the thermal conductivity of the end of the enlarged diameter portion 112. Consequently, in this case as well, the thermal conductivity of the end of the enlarged diameter portion 112 is different from the thermal conductivity of the end 116 on the side opposite to the enlarged diameter portion. In this case, the end of the enlarged diameter portion 112 includes the boss 118 and is a predetermined region extending beyond the boss 118.

Preferably, the Y-component Y-concentration in _Y₂O₃ equivalent to the _Y component contained in the end of the enlarged diameter portion 112 of the support member 100 is 0.4 wt% or more and 5 wt% or less, and the Y-component Y-concentration Y-concentration in _Y₂O₃ equivalent to the Y component contained in the end ₁₁₆ on the side facing the enlarged diameter portion 112 is 0.1 wt% or less. In this way, by providing portions with different Y concentrations in the vertical direction of the AlN support member 100, portions with different thermal conductivity in the vertical direction can be provided, and a substrate holding member 200 in which the heat flow passing through the support member 100 is controlled can be actually constructed.

If a boss 118 is not formed, it is preferable that the _Y2O3 equivalent concentration of the Y component contained in the joint 124 between the electrode embedding member 120 and the support member ₁₀₀ is approximately the same as the _Y2O3 equivalent concentration of the Y component contained in the end of the enlarged diameter portion 112 of the support member 100. In this way, by having approximately the same _{Y2O3 equivalent} concentration of the Y component in the joint 124 of the electrode embedding member 120 and the end of the enlarged diameter portion ₁₁₂ of the support member 100, the bonding strength of the joint surface is stable _, resulting in a highly reliable substrate holding member 200. Note that approximately the same _Y2O3 equivalent concentration of the Y component means that the difference in the _Y2O3 equivalent concentration of each _Y component is 0.1 wt% or less.

The substrate holding member 200 is equipped with terminals 140 and terminal holes 142, in addition to the above-mentioned components. This allows power to be supplied to the electrodes 130.

The substrate holding member of the present invention can adjust the thermal insulation properties of the support member (heat flow through the support member) and the symmetry of the temperature distribution on the mounting surface of the substrate holding member.

[Manufacturing method for substrate holding member]
Next, a method for manufacturing a substrate holding member according to an embodiment of the present invention will be described. Figure 5 is a flowchart showing an example of a method for manufacturing a substrate holding member according to an embodiment of the present invention. As shown in Figure 5, the method for manufacturing a substrate holding member according to an embodiment of the present invention comprises a support member precursor formation step STEP 1, a support member precursor firing step STEP 2, a third ceramic molded body formation step STEP 3, a third ceramic degreased body production step STEP 4, an electrode embedding member precursor formation step STEP 5, an electrode embedding member precursor firing step STEP 6, and a joining step STEP 7.

In the support member precursor formation step 1, a support member precursor 30 is formed, consisting of ceramic raw material powders mainly composed of AlN with varying amounts of sintering aid added. Various methods can be considered for forming the support member precursor 30, which consists of ceramic raw material powders mainly composed of AlN with varying amounts of sintering aid added. For example, it can be formed by the following method. Figures 6(a) to 6(c) are schematic cross-sectional views showing one step of the manufacturing process of a support member according to an embodiment of the present invention.

In the first ceramic molded body formation step STEP 1-1, one or more first ceramic molded bodies 11 are formed from a first ceramic raw material powder mainly composed of AlN, with an adjusted amount of sintering aid added. For example, a slurry can be prepared by mixing ceramic raw material powder with appropriate additives such as _Y₂O₃ as the Y component of the sintering aid, a binder, a plasticizer, and a dispersant _. After granulation of the granules (first ceramic raw material powder) by spray drying or the like, one or more first ceramic molded bodies 11 can be formed by pressure molding. The Y component of the sintering aid may be _Y₂O₃ , or an _oxide containing Y, such as YAG, YAP, YAM, or _{Y₂O₃ ,} may be added as a result of sintering.

The ceramic raw material powder is preferably of high purity, preferably 96% or higher, and more preferably 98% or higher. Furthermore, the average particle size of the ceramic raw material powder is preferably 0.1 μm or more and 1.0 μm or less.

The mixing method may be either wet or dry, and mixers such as ball mills or vibratory mills can be used. For the molding method, known methods such as uniaxial pressure molding or cold isostatic pressing (CIP) can be used. Furthermore, the method for forming the first ceramic molded body 11 is not limited to pressure molding; other methods such as green sheet lamination, casting, or extrusion molding are also applicable.

In the second ceramic molded body formation step STEP 1-2, one or more second ceramic molded bodies 12 are formed from a second ceramic raw material powder, which mainly consists of AlN, with the amount of sintering aid added adjusted to be less than the amount of sintering aid added to the first ceramic raw material powder, or with no sintering aid added. Details such as the method for producing the second ceramic raw material powder and the method for forming the second ceramic molded body 12 may be the same as in the first ceramic molded body formation step STEP 1-1.

One or more first ceramic molded bodies 11 may have their shape refined by machining after molding. Similarly, one or more second ceramic molded bodies 12 may have their shape refined by machining after molding.

In this case, a portion of one ceramic molded body may be shaped to accommodate a containment space provided in the other ceramic molded body. Furthermore, the shrinkage rate of the ceramic molded body with the containment space may be formed to be greater than the shrinkage rate of the portion of the ceramic molded body contained within the containment space. This results in greater shrinkage of the ceramic molded body with the containment space during sintering, causing the outer shape of the containment space to become smaller than the outer shape of the portion of the contained ceramic molded body. As a result, no gap is created between the fired ceramic molded body with the containment space and the fired ceramic molded body containing the containment space at the contact points, and they adhere closely to each other. The difference in shrinkage rates is preferably 0.3% or less.

For example, the shrinkage rate can be varied by changing the molding pressure during the molding of the ceramic molded bodies 11 and 12, such as the CIP pressure, casting pressure, or extrusion pressure, thereby changing the bulk density. Furthermore, the shrinkage rate can also be varied by changing the ceramic particle size and binder ratio of the ceramic molded bodies 11 and 12.

Figure 6(a) shows the first ceramic molded body 11 and the second ceramic molded body 12 after machining so that a portion of the second ceramic molded body 12 is housed within the first ceramic molded body 11.

In the combination process STEP 1-3, one or more first ceramic molded bodies 11 and one or more second ceramic molded bodies 12 are combined to form a support member precursor 30. In this way, a support member precursor 30 can be formed, which is composed of ceramic raw material powders mainly composed of AlN and with different amounts of sintering aid added.

Furthermore, the support member precursor 30, which is composed of ceramic raw material powders with AlN as the main component and varying amounts of sintering aids, may be formed, for example, by the following method. Figures 7(a) to 7(c) are schematic cross-sectional views showing different manufacturing steps of the support member according to the embodiment of the present invention.

In ceramic raw material powder preparation step 1'-1, a first ceramic raw material powder mainly composed of AlN with an adjusted amount of sintering aid is prepared, and a second ceramic raw material powder mainly composed of AlN with an adjusted amount of sintering aid compared to the first ceramic raw material powder, or without any sintering aid. The details of the preparation methods for the first and second ceramic raw material powders in this step may be the same as those in the first ceramic molded body formation step STEP 1-1.

In the support member precursor formation step 1'-2, the support member precursor 30 is formed by placing either the first ceramic raw material powder or the second ceramic raw material powder into a mold and pre-forming it, then placing the other powder into the mold and pre-forming it again, repeating this process one or more times. In this way, a support member precursor 30 can be formed, which is mainly composed of AlN and consists of a first region 101 and a second region 102 with different amounts of sintering aid added.

Furthermore, the pre-formed support member precursor 30 may be shaped by machining after pre-formation. Alternatively, the pre-formed support member precursor 30 may be pre-formed in a simplified shape such as a columnar or cylindrical shape, and the shape of the enlarged diameter portion may be shaped by machining.

The region where the ceramic sintered body formed from the first ceramic raw material powder is placed is called the first region 101, and the region where the ceramic sintered body formed from the second ceramic raw material powder is placed is called the second region 102. That is, in the support member precursor formation process STEP 1, the region where the first ceramic molded body 11 is placed becomes the first region 101 after sintering, and the region where the second ceramic molded body 12 is placed becomes the second region 102 after sintering. The first region 101 of the support member 100, where the first ceramic molded body 11 is fired, has a thermal conductivity of 100 W/mK or higher at 25°C. Furthermore, the second region 102 of the support member 100, where the second ceramic molded body 12 is fired, has a thermal conductivity of 80 W/mK or lower at 25°C.

In the support member precursor firing process STEP 2, the support member precursor 30 is fired to form the support member 100 that supports the electrode embedding member 120. The firing of the support member 100 is preferably performed under atmospheric pressure. Furthermore, the firing temperature is preferably between 1800°C and 2000°C. The firing time is preferably between 1 hour and 12 hours. The firing atmosphere is, for example, a nitrogen or inert gas atmosphere, but an atmosphere such as vacuum may also be used.

In the third ceramic molded body formation step STEP 3, multiple third ceramic molded bodies 13 are formed from a third ceramic raw material powder mainly composed of AlN with a predetermined amount of sintering aid added. Details such as the method for producing the third ceramic raw material powder and the method for forming the third ceramic molded bodies 13 may be the same as in the first ceramic molded body formation step STEP 1-1. Figures 8(a) to 8(d) and 9(a) and 9(b) are schematic cross-sectional views showing one step of the manufacturing process for a substrate holding member according to an embodiment of the present invention.

In the third ceramic molded body formation step STEP 3, some of the ceramic molded bodies may be formed as one or more fourth ceramic molded bodies from a fourth ceramic raw material powder, which mainly consists of AlN and to which a predetermined amount of sintering aid different from that of the third ceramic raw material powder has been added. In this case, the number of third ceramic molded bodies 13 may be one. That is, multiple third and fourth ceramic molded bodies can be produced in combination. In this case, the following description of the third ceramic molded body may also be applied to the fourth ceramic molded body.

The multiple third ceramic molded bodies 13 may be shaped by machining after molding. Furthermore, a groove matching the shape of the electrode 130 may be formed on one side of the third ceramic molded body 13 (the bonding surface with other third ceramic molded bodies 13). Grooves matching the shape of the electrode 130 may also be formed on one side of each of the two third ceramic molded bodies 13. Machining may be performed after degreasing.

In the third ceramic degreased body manufacturing process, STEP 4, multiple third ceramic molded bodies 13 are degreased at a predetermined temperature and for a predetermined time to produce multiple third ceramic degreased bodies 23. For example, they are heat-treated at a temperature of 500°C to 900°C to become the third ceramic degreased bodies 23. The degreasing time is preferably 1 hour to 120 hours. An atmospheric furnace or a nitrogen atmosphere furnace can be used for degreasing, but an atmospheric furnace is preferred.

In step 5, the electrode embedding member precursor formation process, the electrode 130 is prepared, and the electrode 130 and multiple third ceramic degreased bodies 23 are combined to form an electrode embedding member precursor 40, which is formed in a flat plate shape, has a mounting surface 122 on one main surface, and has the electrode 130 embedded in it.

The electrode 130 is prepared by processing it into a shape according to the design of the substrate holding member 200. The electrode 130 can be in various shapes, such as mesh or foil. Furthermore, it can be made from various materials, such as molybdenum or tungsten.

In STEP 6, the electrode embedding member precursor firing process, the formed electrode embedding member precursor 40 is fired under uniaxial pressure perpendicular to the main surface to produce the electrode embedding member 120. The pressing force is preferably 1 MPa or more. The firing temperature is preferably 1700°C to 2000°C. The firing time is preferably 1 hour to 12 hours, and more preferably 1 hour to 5 hours. The firing atmosphere is, for example, a nitrogen or inert gas atmosphere, but may also be a vacuum atmosphere. As a result, multiple third ceramic degreased bodies 23 are sintered to form a ceramic sintered body, which is then integrated to obtain an electrode embedding member 120 with the electrode 130 embedded within it.

In joining step STEP 7, the electrode embedding member 120 and the support member 100 are joined. The joining can be performed using either a joining method with a joining material or a joining method without a joining material.

First, a joining method using a bonding material will be described. First, prepare the bonding material 150 and apply it to at least one of the joining portion 124 that joins the support member 100 on the lower surface facing the mounting surface 122 of the electrode embedding member 120, or to the end face of the support member 100 on the joining portion side. It is preferable to polish the joining portion 124 and the end face of the support member 100 on the joining portion side to a surface roughness Ra of 1.6 μm or less, more preferably 0.4 μm or less. The thickness of the bonding material to be applied is preferably 5 μm or more and 30 μm or less. Next, place the support member 100 on the joining portion 124 and heat while applying pressure perpendicular to the main surface (mounting surface 122). The pressure applied is preferably 5 kPa or more. The heating temperature is preferably 1500°C or more and 1800°C or less. The heating time is preferably 0.5 hours or more and 5 hours or less. The heating atmosphere is, for example, a nitrogen or inert gas atmosphere, but it may also be an atmosphere such as a vacuum. This allows the electrode embedding member 120 and the support member 100 to be joined together.

In this case, it is preferable that the Y component, converted to _Y₂O₃ , is approximately the same in composition between the joint portion ₁₂₄ of the electrode embedding member 120 and the support member 100. When they are approximately the same, the components contained in the bonding material diffuse symmetrically to both the joint portion of the electrode embedding member 120 and the support member 100, so that the components after bonding are symmetrical with respect to the bonding surface, and a good bonding surface is formed. The bonding material can be anything as long as it can bond the electrode embedding member 120 and the support member 100. For example, it may be a paste of mixed powder containing at least _Y₂O₃ powder in AlN powder, which is the same main component as the electrode embedding member ₁₂₀ and the support member 100. Alternatively, it may be a paste containing 90 wt% to 95 wt _% AlN, 5 wt% or more _Y₂O₃ , and containing CaO, MgO, _ZrO₂ , and _SiO₂ to adjust the temperature at which it becomes a melt during bonding as needed.

Next, a joining method without using the bonding material 150 will be described. The support member 100 is placed at the joint 124 on the lower surface of the electrode embedding member 120, which faces the mounting surface 122. It is preferable to polish the joint 124 and the end face of the support member 100 on the joint side to a surface roughness Ra of 0.1 μm or less. Next, the main surface (mounting surface 122) is heated while applying pressure perpendicular to it. The pressure applied is preferably 1 MPa or more. The heating temperature is preferably 1600°C to 2000°C. The heating time is preferably 0.5 hours to 6 hours. The heating atmosphere is, for example, nitrogen or an inert gas atmosphere, but it may also be an atmosphere such as a vacuum. This allows the electrode embedding member 120 and the support member 100 to be joined.

In this case, it is preferable that the _Y2O3 component is substantially the same in the composition of the joint portion 124 of the electrode embedding member 120 and the support member 100. When _they are substantially the same, the oxide components formed on the surface of the AlN particles contained in the joint portion 124 of the electrode embedding member 120 and the support member 100 diffuse symmetrically to the support member 100 and the joint portion 124 of the electrode embedding member 120, respectively, so that the components after bonding become symmetrical with respect to the bonding surface, and a good bonding surface is formed.

Next, the necessary terminal holes 142 are provided in the substrate holding member 200. The drilling of the terminal holes 142 may be performed before or after joining with the support member 100. Then, the terminals 140 are connected to the terminal holes 142 using brazing material or the like. The terminals 140 can be made of Ni or the like. The brazing material can be Au brazing material or the like.

By doing so, it is possible to adjust the thermal insulation properties of the support member (heat flow through the support member) and manufacture a substrate holder that can adjust the symmetry of the temperature distribution on the mounting surface of the substrate holder.

[Examples and Comparative Examples]
(Example 1)
(Fabrication of support members)
A first ceramic raw material powder mainly composed of AlN _with 5 wt% _Y₂O₃ added was prepared. Using this, a first ceramic molded body was formed into a ring shape with an outer diameter of Φ90 mm, an inner diameter of Φ50 mm, a thickness of 25 mm, and a counterbore of Φ65 mm and a depth of 15 mm formed on one side, and was molded using the CIP (Cleaning Injection Plane) method. The bulk density was 2.29 g/ ^cm³ when the molding pressure was adjusted to 1000 kgf/ ^cm² , and the shrinkage rate when fired was 17.31%.

Furthermore, a second ceramic raw material powder mainly composed of AlN without the addition of a sintering aid was prepared. Using this, a second ceramic molded body with a cylindrical section having an outer diameter of Φ65 mm, an inner diameter of Φ50 mm, and a height of 150 mm, and a lower flange section having an outer diameter of Φ90 mm, an inner diameter of 50 mm, and a thickness of 25 mm was formed using the CIP (Cleaning Injection Plane) method. When the molding pressure was adjusted to 1400 kgf/ ^cm² , the bulk density was 2.32 g/ ^cm³ , and the shrinkage rate when fired was 17.01%.

A support member precursor was fabricated by combining the first and second ceramic molded bodies. This was then fired at atmospheric pressure in an _N2 atmosphere at a maximum temperature of 1900°C for a maximum temperature holding time of 2 hours. After the fired support member was processed into a predetermined shape, the end face on the enlarged diameter side was machined to a thickness of Ra 0.4 μm. At this time, the diameter of the enlarged diameter was Φ70 mm.

(Fabrication of electrode embedding components)
A first ceramic raw material powder mainly composed of AlN _with 5 wt% _Y₂O₃ added was prepared. That is, it was the same raw material powder as the one used to form the enlarged diameter portion of the support member in Example 1. Using this, a certain amount of raw material powder was placed in a carbon mold with an inner diameter of Φ320 mm, and after preliminary pressing and leveling, heater electrodes cut from Mo mesh (wire diameter 0.1 mm, mesh size #50, plain weave) into a predetermined shape were placed on top. Furthermore, W pellets (Φ8 mm × 0.2 mm) which would serve as connecting members were placed at the power supply terminal positions, and raw material powder was added to embed the electrodes. Then, after setting the carbon punch, it was hot-pressed and fired at 1800°C or higher and a pressure of 1 MPa or higher. After firing, a boss with a diameter of 310 mm, a thickness of 25 mm, and an outer diameter of 70 mm, an inner diameter of 50 mm, and a height of 2 mm was provided on one side by post-firing processing. The end face of the boss was processed to Ra 0.4 μm.

(Joining)
A 15 μm layer of AlN bonding paste containing 10 wt% _Y₂O₃ was applied to the joint, a support member was placed, and the joint was bonded by heating at 1700°C for 1 hour while applying a force of 5 _kPa perpendicular to the mounting surface. Subsequently, holes were drilled at the positions of the power supply terminals until the W pellets were exposed, and a Φ5 mm, 250 mm long Ni rod was brazed with Au brazing material at 1000°C in a vacuum. Finally, as a finishing process, the outer shape was processed to the predetermined shape. In this way, the substrate holding member of Example 1 was manufactured.

(Example 2)
(Fabrication of support members)
In Example 2, the support member was constructed by using the second ceramic raw material powder to create the enlarged diameter portion and the first ceramic raw material powder to create the cylindrical portion. All other conditions were the same as those for the support member in Example 1.

(Fabrication of electrode embedding components)
A first ceramic raw material powder mainly composed of AlN with 5 _wt % _Y₂O₃ added was prepared. That is, it is the same raw material powder as the one used to form the cylindrical portion of the support member in Example 2. Using this, a third ceramic molded body with a diameter of Φ320 mm and a thickness of 15 mm, and a third ceramic molded body with a diameter of Φ320 mm and a thickness of 20 mm were produced by CIP molding. In addition, a second ceramic raw material powder mainly composed of AlN without any added sintering aid was prepared. That is, it is the same raw material powder as the one used to form the enlarged diameter portion of the support member in Example 2. Using this, a fourth ceramic molded body with a diameter of Φ90 mm and a thickness of 5 mm was formed by CIP molding. This molded body will become the boss after firing.

An electrode identical to that in Example 1 was placed between the third ceramic molded body, and the fourth ceramic molded body was positioned on the bottom side. The molded body was then hot-pressed at 1800°C or higher and a pressure of 1 MPa or higher. Post-firing processing resulted in a boss with a diameter of 310 mm, a thickness of 25 mm, and on one side, an outer diameter of 70 mm, an inner diameter of 50 mm, and a height of 2 mm. The end face of the boss was machined to a thickness of Ra 0.4 μm.

(Joining)
The joining was performed using the same joining material as in Example 1. Finally, as a finishing process, the outer shape was processed to a predetermined shape. In this way, the substrate holding member of Example 2 was manufactured.

(Example 3)
(Fabrication of support members)
A first ceramic raw material powder mainly composed of AlN _with 5 wt% _Y₂O₃ added, and a second ceramic raw material powder mainly composed of AlN without the addition of a sintering aid were prepared. In other words, these are the same raw material powders as the two types of ceramic raw material powders used to form the support member in Example 1.

First ceramic raw material powder was filled into a mold and pre-pressed. Then, second ceramic raw material powder was filled into the mold and pre-pressed again, followed by CIP molding to produce a ceramic molded body with two layers: one made of first ceramic raw material powder and the other of second ceramic raw material powder. A support member precursor was produced by machining this ceramic molded body. In Example 3, the support member precursor was formed from the first ceramic raw material powder from the enlarged diameter portion to about the middle of the cylindrical portion, and from about the middle of the cylindrical portion downwards to the second ceramic raw material powder. This was fired at atmospheric pressure in an _N2 atmosphere at a maximum temperature of 1900°C for a maximum temperature holding time of 2 hours. After firing the support member into a predetermined shape, the end face on the enlarged diameter portion side was machined to Ra 0.4 μm. The diameter of the enlarged diameter portion at this time was Φ70 mm.

(Fabrication of electrode embedding components)
The electrode embedding member was the same as in Example 1. The end face of the boss was machined to a thickness of Ra 0.4 μm.

(Joining)
The bonding was performed by diffusion bonding at 1800°C and 1 MPa without the use of a bonding agent. Finally, as a finishing process, the outer shape was processed to the predetermined shape. In this way, the substrate holding member of Example 3 was manufactured.

[Measurement of thermal conductivity]
Using the first and second ceramic raw material powders, test pieces with a diameter of Φ10 mm and a thickness of 2 mmt were cut from the first and second regions of a member manufactured in the same manner as the support member of Example 1, and their thermal conductivity was measured by the laser flash method. As a result, the thermal conductivity of the first region was 160 W/mK, and that of the second region was 70 W/mK.

[Repeated heating test]
The substrate holding member of the example was subjected to 20 repeated heating cycles from 100°C to 600°C. Afterward, He leakage from the bonding surface was measured and remained consistently low, at 1 × ^10⁻¹⁰ Pa· ^m³ /s or less. Since bonding defects almost always occur within this number of cycles or less, it was confirmed that the substrate holding member of the example is a highly reliable substrate holding member free from bonding defects.

[Symmetry of temperature distribution on the mounting surface]
A substrate was placed on the substrate holding member of the embodiment, and the surface temperature of the center of the substrate was adjusted to 400°C. In this case, in Embodiment 1, a gentle concentric temperature gradient of 4.5°C was generated from the center of the substrate towards the outer edge. In Embodiment 2, a temperature gradient of 1.7°C similar to that of Embodiment 1 was generated, and in Embodiment 3, a temperature gradient of 3.3°C was generated. This confirmed that the substrate holding member of the embodiment can adjust the symmetry of the temperature distribution of the substrate.

Based on the above, it has been confirmed that the support member and substrate holding member of the present invention do not experience stress defects after joining, and that the symmetry of the temperature distribution of the substrate can be adjusted by adjusting the thermal insulation properties of the support member. Furthermore, it has been confirmed that the manufacturing method of the present invention can produce such a substrate holding member.

The present invention is not limited to the embodiments described above, and it goes without saying that it extends to various modifications and equivalents within the spirit and scope of the present invention. Furthermore, the structure, shape, number, position, size, etc., of the components shown in each drawing are for illustrative purposes only and may be modified as appropriate.

11 First ceramic molded body 12 Second ceramic molded body 13 Third ceramic molded body 23 Third degreased ceramic body 30 Support member precursor 40 Electrode embedding member precursor 100 Support member 101 First region 102 Second region 112 Enlarged diameter portion 114 Cylindrical portion 116 End portion 118 facing the enlarged diameter portion Boss 120 Electrode embedding member 122 Mounting surface 124 Joint portion 130 Electrode 140 Terminal 142 Terminal hole 150 Joining material 200 Substrate holding member

Claims (8)

A substrate holding member for mounting a substrate, the support member having a plate-shaped member having one main surface on which the substrate is mounted and another main surface facing the first main surface perpendicular to it, and a boss located on the other main surface of the plate-shaped member,
The support member is formed in a hollow cylindrical shape from a ceramic sintered body mainly composed of AlN.
The support member is composed of a first region and a second region arranged in the vertical direction,
The second region is a ring-shaped disc joined to the boss and having the same outer diameter as the boss.
The first region is a hollow cylindrical member joined to the disc,
The thermal conductivity of the first region at 25°C is 100 W/mK or more.
A support member characterized in that the thermal conductivity of the second region at 25°C is 80 W/mK or less. The Y _{-2O -3} equivalent concentration of the Y component included in the first region is 0.4 wt% or more and 5 wt% or less.
The support member according to claim 1 _, characterized in that the Y component contained in the second region has a _Y2O3 equivalent concentration of 0.1 wt% or less. The support member according to claim 1 or 2, characterized in that one end of the support member is composed of the first region, and the other end of the support member is composed of the second region. A substrate holding member,
An electrode embedding member having electrodes embedded in a flat plate-shaped electrode, made of a ceramic sintered body mainly composed of AlN, comprising a plate-shaped member having one main surface on which a substrate is placed and another main surface facing the first main surface perpendicular to it, and an electrode embedding member having a cylindrical boss located on the other main surface of the plate-shaped member,
It comprises a ceramic sintered body mainly composed of AlN, having an enlarged diameter portion provided at the end on the electrode embedding member side and a cylindrical portion with a smaller diameter than the enlarged diameter portion, and a support member for supporting the electrode embedding member,
The enlarged diameter portion and the cylindrical portion are aligned in the vertical direction.
The enlarged portion is joined to the boss, and the outer diameter of the enlarged portion is the same as the outer diameter of the boss.
A substrate holding member characterized in that the thermal conductivity of the enlarged diameter portion is the same as that of the boss, the thermal conductivity of the cylindrical portion is different from that of the enlarged diameter portion, and the thermal conductivity of the cylindrical portion is the same as that of the plate-shaped member. The Y-component Y _equivalent concentration contained in the end of the enlarged diameter portion is 0.4 wt% or _more and 5 wt% or less.
The substrate holding member according to claim 4, characterized in that the Y-component _{Y equivalent} concentration of the end portion on the side facing the enlarged diameter portion is 0.1 wt% or less. The substrate holding member according to claim ₅ , characterized in that the Y _- component concentration of Y contained in the boss of the electrode embedding member is substantially the same as the Y _- component concentration of _Y contained in the end of the enlarged diameter portion of the support member. A method for manufacturing a substrate holding member,
A step of forming one or more first ceramic molded bodies from a first ceramic raw material powder having AlN as the main component and an adjusted amount of sintering aid added,
A step of forming one or more second ceramic molded bodies from a second ceramic raw material powder, the second ceramic raw material powder having AlN as the main component, wherein the amount of sintering aid added is adjusted to be less than the amount of sintering aid added to the first ceramic raw material powder, or the second ceramic raw material powder to which no sintering aid is added,
A step of forming a support member precursor by combining the one or more first ceramic molded bodies and the one or more second ceramic molded bodies,
A step of manufacturing a support member by firing the support member precursor,
A step of forming a plurality of third ceramic molded bodies from a third ceramic raw material powder mainly composed of AlN with a predetermined amount of sintering aid added, and a step of forming a fourth ceramic molded body from a fourth ceramic raw material powder,
A step of producing a plurality of degreased third ceramic bodies by degreasing the plurality of third ceramic molded bodies at a predetermined temperature and for a predetermined time and longer,
A step of producing a boss precursor by degreasing the fourth ceramic molded body at a predetermined temperature and for a predetermined time,
The process involves preparing electrodes, combining the electrodes and the plurality of third ceramic degreased bodies to form an electrode embedding member precursor that has a mounting surface on one main surface, is formed in a flat plate shape, and has electrodes embedded in it.
A step of manufacturing an electrode embedding member by uniaxial pressure firing perpendicular to the main surface of the electrode embedding member precursor, with the boss precursor placed on top of the other main surface of the electrode embedding member precursor,
The process includes the steps of joining the electrode embedding member and the support member by placing the support member on the boss formed by the boss precursor of the electrode embedding member and heating it while applying pressure perpendicular to the main surface, or by preparing a bonding material, applying the bonding material to at least one of the boss of the electrode embedding member or the end face of the support member to be joined, placing the support member on the boss and heating it while applying pressure perpendicular to the main surface,
The outer diameter of the second ceramic molded body is the same as the outer diameter of the boss, and is joined to the boss.
The one or more first ceramic molded bodies are arranged perpendicularly to the second ceramic molded body,
The first region of the support member where the first ceramic molded body is fired has a thermal conductivity of 100 W/mK or more at 25°C.
A method for manufacturing a substrate holding member, characterized in that the second region of the support member where the second ceramic molded body is fired has a thermal conductivity of 80 W/mK or less at 25°C. A method for manufacturing a substrate holding member,
A step of preparing a first ceramic raw material powder mainly composed of AlN with an adjusted amount of sintering aid added, and a second ceramic raw material powder mainly composed of AlN with an adjusted amount of sintering aid added, or a second ceramic raw material powder in which no sintering aid is added,
A step of forming a support member precursor by placing either the first ceramic raw material powder or the second ceramic raw material powder into a mold and pre-forming it, and then placing the other into the mold and pre-forming it, and repeating this process one or more times,
A step of manufacturing a support member by firing the support member precursor,
A step of forming a plurality of third ceramic molded bodies from a third ceramic raw material powder mainly composed of AlN with a predetermined amount of sintering aid added, and a step of forming a fourth ceramic molded body from a fourth ceramic raw material powder,
A step of producing a plurality of degreased third ceramic bodies by degreasing the plurality of third ceramic molded bodies at a predetermined temperature and for a predetermined time and longer,
A step of producing a fourth degreased ceramic body by degreasing the fourth ceramic molded body at a predetermined temperature and for a predetermined time,
The process involves preparing electrodes, combining the electrodes and the plurality of third ceramic degreased bodies to form an electrode embedding member precursor that has a mounting surface on one main surface, is formed in a flat plate shape, and has electrodes embedded in it.
The process involves forming a cylindrical boss precursor from the fourth ceramic degreased body,
A step of manufacturing an electrode embedding member by uniaxial pressure firing perpendicular to the main surface of the electrode embedding member precursor, with the boss precursor placed on top of the other main surface of the electrode embedding member precursor,
The process includes the steps of joining the electrode embedding member and the support member by placing the support member on the boss formed by the boss precursor of the electrode embedding member and heating it while applying pressure perpendicular to the main surface, or preparing a bonding material, applying the bonding material to at least one of the end faces of the electrode embedding member to be joined to the boss or the support member, placing the support member on the boss and heating it while applying pressure perpendicular to the main surface,
The molded body of the second ceramic raw material powder is a ring-shaped disc having the same outer diameter as the boss, and is joined to the boss.
The molded body of the first ceramic raw material powder is arranged perpendicularly to the molded body of the second ceramic raw material powder,
The first region of the support member where the molded body of the first ceramic raw material powder is fired has a thermal conductivity of 100 W/mK or more at 25°C.
A method for manufacturing a substrate holding member, characterized in that the second region of the support member where the molded body of the second ceramic raw material powder is fired has a thermal conductivity of 80 W/mK or less at 25°C.