Holding device

Abstract

The temperature distribution of the workpiece held by the holding device is made uniform. [Solution] The holding device (1) includes a base member (20) having a flow path (28) formed therein. The base member (20) includes a first member (21), a second member (22) that is stacked on the first member (21) in a first direction, and a joining member (23) that joins the first member (21) and the second member (22). The first member (21) has a first hole (211) that penetrates the first member (21) in the first direction. The second member (22) has a second hole (221) that penetrates the second member (22) in the first direction. The joining member (23) has a third hole (231) that penetrates the joining member (23) in the first direction and is connected to the first hole (211) and the second hole (221). At least one of the central axes (L1) of the first hole (211), the central axis (L2) of the second hole (221), and the central axis (L3) of the third hole (231) is positioned at a different position from the other central axes when viewed in the first direction.

Description

[Technical Field]

[0001] The present disclosure relates to a retention device. [Background technology]

[0002] An electrostatic chuck is known as an example of a holding device for holding a workpiece such as a wafer during semiconductor manufacturing. An electrostatic chuck generally includes a ceramic substrate and a cooling base (base member) for cooling the ceramic substrate, and is configured to hold a wafer on the surface of the ceramic substrate by electrostatic attraction. The ceramic substrate and the base member are bonded to each other by a bonding layer interposed therebetween. The ceramic substrate is cooled by heat transfer (heat dissipation) between the base member and the ceramic substrate via the bonding layer.

[0003] The ceramic substrate has electrodes such as a wafer attracting electrode (chuck electrode) inside. A power supply terminal is electrically connected to the chuck electrode through a via and a terminal connection portion. An electrostatic attraction is generated when power is supplied from an external power source to the chuck electrode through the power supply terminal, and this electrostatic attraction attracts and holds the wafer on the holding surface of the ceramic substrate. Terminal holes are formed inside the ceramic substrate and the base member for inserting the power supply terminal. Furthermore, in plasma processing such as plasma etching, a thermally conductive gas such as helium gas is supplied between the ceramic substrate and the wafer to remove heat from the wafer. Gas holes are formed inside the ceramic substrate and the base member, extending from the back surface of the base member to the holding surface of the ceramic substrate, for allowing the thermally conductive gas supplied from the outside to flow toward the wafer.

[0004] Patent Document 1 discloses an electrostatic chuck in which the cooling substrate is composed of a ceiling substrate and a grooved substrate disposed below the ceiling substrate. The lower surface of the ceiling substrate and the upper surface of the grooved substrate are joined by a ceiling joining layer. The space generated between the grooves formed in the grooved substrate and the ceiling substrate serves as a refrigerant flow path through which a refrigerant for cooling the cooling substrate flows. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 7583698 Summary of the Invention [Problem to be solved by the invention]

[0006] In the configuration disclosed in Patent Document 1, when holes such as terminal holes and gas holes are formed so as to penetrate the cooling substrate, the holes (spaces) are less likely to transfer heat (result in poor heat dissipation) than areas other than the holes. As a result, the temperature of the holes (spaces) may differ from the temperature of areas where no holes are formed. Furthermore, when multiple holes are formed in the cooling substrate, the distance between the refrigerant flow path and the holes often differs for each of the multiple holes, and the temperature of the holes may differ for each of the holes. In such cases, the temperature of the ceramic substrate may not be uniform due to heat transfer (heat dissipation) between the cooling substrate and the ceramic substrate. To ensure uniform processing accuracy, such as etching, on the wafer, it is preferable that the temperature of the entire wafer during processing is uniform.

[0007] An object of the present disclosure is to make the temperature distribution of an object held by a holding device uniform. [Means for solving the problem]

[0008] The holding device according to the present disclosure is a holding device comprising a base member having a flow path formed therein, the base member comprising a first member, a second member stacked on top of the first member in a first direction, and a joining member joining the first member and the second member, wherein the first member has a first hole portion formed therein that penetrates the first member in the first direction, the second member has a second hole portion formed therein that penetrates the second member in the first direction, and the joining member has a third hole portion formed therein that penetrates the joining member in the first direction and is connected to the first hole portion and the second hole portion, and at least one of the first central axis that is the central axis of the first hole portion, the second central axis that is the central axis of the second hole portion, and the third central axis that is the central axis of the third hole portion, and the other central axes are arranged at different positions when viewed in the first direction. [Effects of the Invention]

[0009] According to the present disclosure, the temperature distribution of the workpiece held by the holding device can be made uniform. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is an explanatory diagram that schematically shows the general configuration of a holding device according to a first embodiment. [Figure 2] FIG. 2 is a cross-sectional view that schematically illustrates the internal structure of the holding device according to the first embodiment. [Figure 3] FIG. 3 is a schematic cross-sectional view showing an enlarged view of the periphery of the first hole portion, the second hole portion, and the third hole portion of the base member. [Figure 4] FIG. 4 is a schematic plan view showing an enlarged view of the periphery of the first hole portion, the second hole portion, and the third hole portion of the base member. [Figure 5] FIG. 5 is an enlarged cross-sectional view schematically illustrating the internal structure of the holding device according to the first embodiment. [Figure 6] FIG. 6 is a schematic cross-sectional view showing an enlarged view of the periphery of the first hole, the second hole, and the third hole of the base member according to a modified example of the first embodiment. [Figure 7]FIG. 7 is a schematic cross-sectional view showing an enlarged view of the periphery of the first hole portion, the second hole portion, and the third hole portion of the base member according to the second embodiment. [Figure 8] FIG. 8 is a schematic cross-sectional view showing an enlarged view of the periphery of the first hole portion, the second hole portion, and the third hole portion of the base member according to the third embodiment. [Figure 9] FIG. 9 is a schematic cross-sectional view showing an enlarged view of the periphery of the first hole portion, the second hole portion, and the third hole portion of the base member according to the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] First, embodiments of the present disclosure will be listed and described. (1) A holding device according to the present disclosure is a holding device comprising a base member having a flow path formed therein, the base member comprising a first member, a second member stacked on the first member in a first direction, and a joining member joining the first member and the second member, wherein the first member has a first hole portion formed therein that penetrates the first member in the first direction, the second member has a second hole portion formed therein that penetrates the second member in the first direction, and the joining member has a third hole portion formed therein that penetrates the joining member in the first direction and is connected to the first hole portion and the second hole portion, and at least one of the first central axis that is the central axis of the first hole portion, the second central axis that is the central axis of the second hole portion, and the third central axis that is the central axis of the third hole portion, and the other central axes are arranged at different positions when viewed in the first direction.

[0012] At least one of the first, second, and third central axes is positioned at a different position from the other central axes when viewed in the first direction. In this case, a portion of a component constituting one of the first, second, and third holes, whose central axis is positioned at a different position from that of one of the first, second, and third holes, is disposed inside a single hole (space) formed by the connection of the first, second, and third holes. Therefore, heat is conducted from the internal spaces of the first, second, and third holes through a portion of the component disposed inside the single space. This results in a more gradual temperature gradient within the space formed by the connection of the holes than when the central axes of the first, second, and third holes are positioned at the same position when viewed in the first direction, making it easier to achieve a uniform temperature distribution throughout the base member. In this way, the holding device according to the present disclosure can uniform the temperature distribution of the workpiece.

[0013] (2) In the holding device described in (1), the spatial regions formed inside each of the first hole portion, the second hole portion, and the third hole portion in the base member may be arranged to overlap each other when viewed in the first direction.

[0014] In this case, the first hole portion, the second hole portion, and the third hole portion form a through hole that penetrates the base member in the first direction, and the formed through hole can be used without hindrance for purposes such as a terminal hole, a gas hole, etc. Also, the thermal conductivity in the portion where such a through hole is formed in the base member is improved.

[0015] (3) In the holding device described in (1) or (2), it is preferable that the diameter of the third hole portion is equal to or larger than the diameter of the first hole portion and the diameter of the second hole portion.

[0016] In this case, it is possible to prevent a portion of the joining member forming the third hole portion from peeling off and entering the first hole portion and the second hole portion. Furthermore, since it is possible to prevent the joining member forming the third hole portion from being disposed inside the first hole portion and the second hole portion, it becomes easier to insert another component into the through hole formed by the first hole portion, the second hole portion, and the third hole portion. In this case, it is more preferable that the diameter of the second hole portion is equal to or larger than the diameter of the first hole portion. This makes it easier to insert another component into the through hole formed by the first hole portion, the second hole portion, and the third hole portion.

[0017] (4) In the holding device described in any one of (1) to (3), the flow path may be formed in any one of the first member, the second member, and the joining member, and at least one of the first hole portion, the second hole portion, and the third hole portion formed in a member in which the flow path is not formed may be located closer to the flow path when viewed in the first direction than the hole portion formed in the member in which the flow path is formed.

[0018] When a heat medium flows inside the flow path, the temperature of the heat medium is more easily transferred to the first member, the second member, and the joining member that constitute the base member, the closer the portion is to the flow path. In the base member, at least one of the holes formed in the member in which the flow path is not formed is provided closer to the flow path as viewed in the first direction than the hole formed in the member in which the flow path is formed. This allows the temperature of the internal space of the through hole formed by the first hole, the second hole, and the third hole to be closer to the temperature of the heat medium than when the first hole, the second hole, and the third hole are provided at positions the same distance from the flow path.

[0019] (5) In the holding device described in any one of (1) to (4), the flow path may be formed in any two of the first member, the second member, and the joining member, and the first hole portion, the second hole portion, and the third hole portion formed in the member in which the flow path is not formed may be located closer to the flow path when viewed in the first direction than the hole portion formed in the member in which the flow path is formed.

[0020] When a heat medium flows inside the flow path, the temperature of the heat medium is more easily transferred to the first member, the second member, and the joining member that constitute the base member the closer they are to the flow path. In the base member, the holes formed in the members that do not have flow paths are located closer to the flow path as viewed in the first direction than the holes formed in the members that have flow paths. This allows the temperature of the internal space of the through hole formed by the first hole, the second hole, and the third hole to be closer to the temperature of the heat medium than when the first hole, the second hole, and the third hole are located at positions that are the same distance from the flow path.

[0021] (6) The holding device described in any of (1) to (5) may include a plate-like member having a first surface for holding the workpiece and a second surface opposite to the first surface, the plate-like member being stacked in the first direction on the second member of the base member with the second surface facing the base member, and an adhesive layer bonding the second surface of the plate-like member to the second member of the base member.

[0022] Since the temperature of the base member is uniform, heat is transferred from the base member to the plate-like member through the adhesive layer, thereby uniforming the temperature of the plate-like member, and thereby uniforming the temperature of the workpiece held on the first surface of the plate-like member.

[0023] (7) In the holding device described in any one of (1) to (6), the plate-shaped member has a fourth hole portion formed therein that is recessed at least from the second surface of the plate-shaped member toward the first surface, and the adhesive layer has a fifth hole portion formed therein that penetrates the adhesive layer in the first direction and is connected to the second hole portion and the fourth hole portion, and when the central axis of the fourth hole portion is defined as a fourth central axis and the central axis of the fifth hole portion is defined as a fifth central axis, at least one of the first central axis, the second central axis, and the third central axis and at least one of the fourth central axis and the fifth central axis may be positioned at different positions when viewed in the first direction.

[0024] In this case, a single space is formed by the through-holes formed by the first, second, and third holes penetrating the base member in the first direction and the holes formed by the fourth and fifth holes connecting to each other. At least one of the first, second, and third central axes and at least one of the fourth and fifth central axes are positioned at different positions when viewed in the first direction, so that at least a portion of the member forming the first, second, or third hole is disposed within the single space. Therefore, heat is conducted within the internal space of each hole through a portion of the member disposed within the single space. This improves thermal conductivity within the space formed by the interconnection of the holes compared to when the central axes of the first, second, third, fourth, and fifth holes are positioned at the same position when viewed in the first direction.

[0025] (8) In the holding device described in any one of (1) to (7), the plate-shaped member has a fourth hole portion formed therein that is recessed at least from the second surface of the plate-shaped member toward the first surface, and the adhesive layer has a fifth hole portion formed therein that penetrates the adhesive layer in the first direction and is connected to the second hole portion and the fourth hole portion, and when the central axis of the fourth hole portion is defined as a fourth central axis and the central axis of the fifth hole portion is defined as a fifth central axis, at least one of the second central axis, the fourth central axis, and the fifth central axis may be positioned at a different position from the other central axes when viewed in the first direction.

[0026] In this case, a single space is formed by the through-holes formed by the first, second, and third holes penetrating the base member in the first direction and the holes formed by the fourth and fifth holes connecting to each other. At least one of the second, fourth, and fifth central axes is positioned at a different location when viewed in the first direction, so that a portion of the member forming any of the first, second, and third holes and at least a portion of the plate-like portion or adhesive layer are disposed within the single space. Therefore, heat is conducted within the internal space of each hole through a portion of the member disposed within the single space. This improves thermal conductivity within the space formed by the interconnection of the holes compared to when the central axes of the second, fourth, and fifth holes are positioned at the same location when viewed in the first direction.

[0027] <Details of the first embodiment of the present disclosure> The schematic configuration of a first embodiment of the present disclosure will be described with reference to FIGS. 1 to 5. The present disclosure is not limited to these examples, but is defined by the claims, and all modifications within the meaning and scope of the claims are intended to be included. In the following description, for multiple identical components, only some components may be designated by reference numerals, and the reference numerals for other components may be omitted. In this specification, the configuration of the holding device 1 will be described with the positive Z-axis direction as the upward direction, the negative Z-axis direction as the downward direction, and the XY plane direction as the horizontal direction. However, in actual use of the holding device 1, different arrangements may be used. Furthermore, in this specification, "horizontal" and "parallel" are intended to include arrangements that are recognized as substantially horizontal and parallel.

[0028] The holding device 1 of the first embodiment is an electrostatic chuck that can attract and hold a workpiece (hereinafter referred to as a "wafer W"). The workpiece may be a semiconductor wafer, a glass substrate, or the like. The electrostatic chuck is attached, for example, inside a processing chamber of a semiconductor manufacturing device (not shown), and is used to perform various processes, such as film formation and etching, on the wafer W using plasma.

[0029] 1, the holding device 1 of the first embodiment includes a plate-shaped member 10 and a base member 20. The plate-shaped member 10 and the base member 20 are bonded to each other by an adhesive layer 30 disposed between the plate-shaped member 10 and the base member 20. The adhesive layer 30 is made of an adhesive such as a silicone-based resin, an acrylic-based resin, or an epoxy-based resin.

[0030] The plate-shaped member 10 is a plate-shaped member that is substantially circular when viewed in the Z-axis direction and has insulating properties. In the first embodiment, the plate-shaped member 10 has a shape with a diameter of about 300 mm and a thickness of about 3 mm, for example. The plate-shaped member 10 is formed of a ceramic containing, for example, alumina (Al2O3), aluminum nitride (AlN), or the like as its main component. In this specification, "containing" as a "main component" means that the content of that component is the highest.

[0031] The plate-shaped member 10 has a first surface S1 for holding the wafer W, and a second surface S2 (shown in FIG. 2) located on the opposite side of the first surface S1. The first surface S1 and the second surface S2 are substantially circular surfaces extending in a direction perpendicular to the Z-axis direction (the XY plane direction, the horizontal direction). The first surface S1 is disposed on the upper side of the plate-shaped member 10, and the second surface S2 is disposed on the lower side of the plate-shaped member 10.

[0032] A chuck electrode 51 made of a conductive material such as tungsten or molybdenum is disposed inside the plate-like member 10. The chuck electrode 51 has a planar shape that is, for example, substantially parallel to the first surface S1. A power supply terminal 91 shown in FIG. 1 is electrically connected to the chuck electrode 51 through a via 93 and a terminal connection portion 92 shown in FIG. 2. Power is supplied to the chuck electrode 51 from an external power supply (not shown) through the power supply terminal 91. When power is supplied from the external power supply to the chuck electrode 51 through the power supply terminal 91, an electrostatic attraction force is generated, and the wafer W is attracted and held on the first surface S1 by the electrostatic attraction force. Note that the power supply terminal 91 is not shown in FIG. 2 and subsequent figures in order to clearly show the configuration of a holding device non-through hole 90 (described later).

[0033] 1, the base member 20 is a substantially disk-shaped member having the same diameter as the plate-shaped member 10. The base member 20 is disk-shaped with a larger diameter than the plate-shaped member 10, for example, having a diameter of about 340 mm and a thickness of about 20 mm. The base member 20 is formed from a metal such as aluminum or an aluminum alloy, a ceramic containing silicon carbide (SiC), alumina, aluminum nitride, or the like as its main component, or a composite material of a metal and ceramic.

[0034] 2, the base member 20 has a third surface S3 disposed on the plate-shaped member 10 side, and a fourth surface S4 disposed on the opposite side to the third surface S3. The third surface S3 and the fourth surface S4 are each a substantially circular surface extending in a direction perpendicular to the Z-axis direction. The third surface S3 is disposed on the upper side of the base member 20, and the fourth surface S4 is disposed on the lower side of the base member 20. The third surface S3 is adhered to the second surface S2 of the plate-shaped member 10 by an adhesive layer 30.

[0035] A flow path 28 is formed inside the base member 20. The flow path 28 is a flow path with a width of approximately 5 mm to 10 mm and a depth of approximately 10 mm, and is formed inside the base member 20 so as to have, for example, a spiral shape in a plan view. A portion of the flow path 28 is formed with an end 28B extending from the spiral portion toward the fourth surface S4 of the base member 20, and the end 28B is connected to a refrigerant circulator (not shown). The refrigerant circulator is configured to circulate a refrigerant through the flow path 28. The refrigerant may be a fluorine-based inert liquid, water, or the like. When the refrigerant flows through the flow path 28, the base member 20 is cooled. The plate-shaped member 10 is cooled by heat transfer between the base member 20 and the plate-shaped member 10 via the adhesive layer 30. This controls the temperature of the wafer W held on the first surface S1 of the plate-shaped member 10. Note that the flow path 28 is not limited to a refrigerant, and various heat transfer media, such as a heating medium for transferring heat to the base member 20 to warm it, may also be used. As shown in FIG. 2, the flow path 28 is formed to have a rectangular shape in the cross section of the XZ plane, but the flow path 28 may be formed to have other shapes such as a circle or an ellipse.

[0036] The adhesive layer 30 is disposed between the second surface S2 of the plate-like member 10 and the third surface S3 of the base member 20. The thickness of the adhesive layer 30 is, for example, about 0.1 mm to 1 mm. The adhesive layer 30 is made of an adhesive having a predetermined thermal conductivity and thermal expansion. The adhesive that constitutes the adhesive layer 30 may be an organic resin material, a metal adhesive material, or an inorganic adhesive material. The organic resin material may be, for example, a silicone-based resin, a fluororesin, an acrylic resin, or an epoxy-based resin. The metal adhesive material may be, for example, a metal such as aluminum or an aluminum alloy. The inorganic adhesive material may be, for example, a material whose main components are ceramic and an inorganic polymer.

[0037] The plate-shaped member 10 is stacked in the first direction on the second member 22 of the base member 20 with the second surface S2 facing the base member 20. In this state, the second surface S2 of the plate-shaped member 10 and the upper surface 22A of the second member 22 of the base member 20 are bonded together by an adhesive layer 30. In this specification, the first direction is the up-down direction (Z-axis direction) that is perpendicular to each of the first surface S1, the second surface S2, the third surface S3, and the fourth surface S4.

[0038] 1 and 2, the base member 20 includes a first member 21 and a second member 22. The first member 21 and the second member 22 are joined by a joining member 23 disposed between the first member 21 and the second member 22. The joining member 23 is a metal such as aluminum or an aluminum alloy, and the first member 21 and the second member 22 are joined by melting the joining member 23 at a high temperature.

[0039] Both the first member 21 and the second member 22 are formed in a substantially circular plate shape when viewed in the Z-axis direction. As shown in FIGS. 2 and 3 , the first member 21 has a lower surface 21B that forms the fourth surface S4 and an upper surface 21A located opposite the lower surface 21B. The second member 22 has an upper surface 22A that forms the third surface S3 and a lower surface 22B located opposite the upper surface 22A. The second member 22 is overlapped on the upper surface 21A of the first member 21 in the first direction (Z-axis direction) with the lower surface 22B facing the first member 21, and the upper surface 21A of the first member 21 and the lower surface 22B of the second member 22 are joined by a joining member 23. In the first embodiment, a groove recessed from the lower surface 22B of the second member 22 toward the upper surface 22A is formed in the second member 22, thereby forming the flow path 28 described above inside the second member 22.

[0040] 3, a first upper hole 211A is formed in the upper surface 21A of the first member 21. A first lower hole 211B is formed in the lower surface 21B. The first upper hole 211A and the first lower hole 211B are connected to each other, thereby forming a first hole 211 that penetrates the first member 21 in the first direction (Z-axis direction).

[0041] A second upper hole 221A is formed in the upper surface 22A of the second member 22. A second lower hole 221B is formed in the lower surface 22B. The second upper hole 221A and the second lower hole 221B are connected to each other, thereby forming a second hole 221 that penetrates the second member 22 in the first direction (Z-axis direction).

[0042] A third upper hole 231A is formed in the joining member 23 at a position on the second member 22 side facing the second lower hole 221B formed in the lower surface 22B of the second member 22. A third lower hole 231B is formed in the joining member 23 at a position on the first member 21 side facing the first upper hole 211A formed in the upper surface 21A of the first member 21. The third upper hole 231A and the third lower hole 231B are connected to each other, thereby forming a third hole 231 that penetrates the joining member 23 in the first direction (Z-axis direction) and is connected to the first hole 211 and the second hole 221. A hole that penetrates the base member 20 in the first direction, formed by the first hole 211, the second hole 221, and the third hole 231 being connected to each other, is referred to as a base through-hole 40.

[0043] The base through-holes 40 are connected to the plate-like member through-holes 60 or the plate-like member non-through-holes 70 described below to form the holding device through-holes 80 or the holding device non-through-holes 90. The holding device through-holes 80 function as gas holes or lift pin holes. The gas holes are holes for allowing thermally conductive gas supplied from the outside to flow from the inside of the base member 20 toward the first surface S1 of the plate-like member 10. The lift pin holes are holes for inserting lift pins that move the wafer W up and down relative to the first surface S1. The holding device non-through-holes 90 function as terminal holes for arranging power supply terminals 91 inside the holding device 1.

[0044] 3 and 4, the detailed configurations of the first hole 211, the second hole 221, and the third hole 231 (base through-hole 40) in the base member 20 will be described. FIG. 3 shows a cross section of the base member 20 cut along an XY plane that passes through the first hole 211, the second hole 221, and the third hole 231. FIG. 4(A) shows the first hole 211, the second hole 221, the third hole 231, and their vicinity of the base member 20 as viewed in a first direction. Here, "viewed in the first direction" corresponds to viewing the base member 20 from the Z-axis positive direction side (viewed from above) and from the Z-axis negative direction side (viewed from below), and FIG. 4 particularly shows a view from the Z-axis positive direction side. is equivalent to

[0045] As shown in FIG. 3, the first upper hole 211A and the first lower hole 211B are provided as round holes having approximately the same diameter on the upper surface 21A and the lower surface 21B of the first member 21, respectively. The first upper hole 211A and the first lower hole 211B are arranged at approximately the same position on the upper surface 21A and the lower surface 21B of the first member 21 when viewed in the first direction (Z-axis direction). The first hole 211 formed by connecting the first upper hole 211A and the first lower hole 211B is a cylindrical hole extending in the first direction so as to be perpendicular to the upper surface 21A and the lower surface 21B of the first member 21. That is, the central axis L1 of the first hole 211 extends in the first direction. The central axis L1 is an example of a first central axis.

[0046] The second upper hole 221A and the second lower hole 221B are provided as round holes having approximately the same diameter on the upper surface 22A and the lower surface 22B of the second member 22, respectively. The second upper hole 221A and the second lower hole 221B are arranged at approximately the same position on the upper surface 22A and the lower surface 22B of the second member 22, respectively, when viewed in the first direction (Z-axis direction). The second hole 221 formed by connecting the second upper hole 221A and the second lower hole 221B is a cylindrical hole extending in the first direction so as to be perpendicular to the upper surface 22A and the lower surface 22B of the second member 22. That is, the central axis L2 of the second hole 221 extends in the first direction. The central axis L2 is an example of a second central axis.

[0047] The third upper hole 231A and the third lower hole 231B are round holes having approximately the same diameter and are formed in the upper and lower parts of the joining member 23. The third upper hole 231A and the third lower hole 231B are arranged in approximately the same position in the upper and lower parts of the joining member 23 when viewed in the first direction (Z-axis direction). The third hole 231 formed by connecting the third upper hole 231A and the third lower hole 231B is a cylindrical hole extending in the first direction, similar to the first hole 211 and the second hole 221. That is, the central axis L3 of the third hole 231 extends in the first direction. The central axis L3 is an example of a third central axis.

[0048] 3, the central axis L1 of the first hole portion 211, the central axis L2 of the second hole portion 221, and the central axis L3 of the third hole portion 231 are disposed at different positions from one another when viewed in the first direction (Z-axis direction). That is, the central axis L1, the central axis L2, and the central axis L3 extend parallel to one another in the base through-hole 40 and are disposed without overlapping.

[0049] Fig. 4(A) shows the arrangement of the first hole portion 211, the second hole portion 221, and the third hole portion 231 in the base member 20 as viewed from above. Fig. 4(B) shows the arrangement of the first hole portion 211, the second hole portion 221, and the third hole portion 231 in a conventional base member 29 as viewed from above. In conventional base member 29, the first hole portion 211, the second hole portion 221, and the third hole portion 231 are generally formed with the central axis L1, the central axis L2, and the central axis L3 each being positioned at the same position as viewed in the first direction (Z-axis direction).

[0050] The internal space of the base through-hole 40 has lower thermal conductivity than the surrounding area of ​​the base through-hole 40. Therefore, in the base member 20, the area where the base through-hole 40 is formed and the surrounding area may become hotter than other areas, and may have a different temperature than other areas.

[0051] To solve this problem, as shown in FIG. 4A , the base member 20 is formed with the first hole 211, the second hole 221, and the third hole 231 such that the central axes L1, L2, and L3 are positioned at different positions when viewed in the first direction (Z-axis direction). As a result, when the base through-hole 40 is viewed in the first direction, a portion of the upper surface 21A of the first member 21, which is the periphery of the first hole 211, overlaps with a portion of the space inside the second hole 221. The portion of the upper surface 21A of the first member 21 overlaps with a portion of the space inside the second hole 221, facilitating heat conduction between the first hole 211, the second hole 221, and the third hole 231 via the overlapping portion. This allows the base member 20 to improve the heat conductivity inside the base through-hole 40 compared to when a portion of the member forming the base through-hole 40 is not disposed inside the base through-hole 40. Therefore, the temperature of the portion of the base member 20 where the base through-hole 40 is formed and its surrounding area is prevented from becoming different from the temperature of other portions.

[0052] In the first embodiment, as shown in FIGS. 3 and 4 , the spatial regions formed inside the first hole portion 211, the second hole portion 221, and the third hole portion 231 are arranged to overlap each other when viewed in the first direction (Z-axis direction). In this case, the internal space of the base through-hole 40 is arranged to penetrate the base member 20 in the first direction. This allows a lift pin or a power supply terminal 91 to be inserted in the first direction into the inside of the holding device through-hole 80 or the holding device non-through-hole 90 formed using the base through-hole 40. Therefore, the holding device through-hole 80 or the holding device non-through-hole 90 can function as a lift pin hole, a terminal hole, or the like. Furthermore, when the holding device through-hole 80 formed using the base through-hole 40 is used as a gas hole, a thermally conductive gas can be smoothly flowed in the first direction from the inside of the base member 20 toward the first surface S1 of the plate-like member 10.

[0053] The hole diameter of the first hole portion 211 is defined as hole diameter R1. Hole diameter R1 corresponds to the hole diameter of the first upper hole portion 211A and the first lower hole portion 211B in the horizontal direction. The hole diameter of the second hole portion 221 is defined as hole diameter R2. Hole diameter R2 corresponds to the hole diameter of the second upper hole portion 221A and the second lower hole portion 221B in the horizontal direction. The hole diameter of the third hole portion 231 is defined as hole diameter R3. Hole diameter R3 corresponds to the hole diameter of the third upper hole portion 231A and the third lower hole portion 231B in the horizontal direction. As shown in FIGS. 3 and 4 , the hole diameter R3 of the third hole portion 231 is preferably equal to or greater than the hole diameter R1 of the first hole portion 211 and the hole diameter R2 of the second hole portion 221. When a portion of the bonding member 23 is disposed so as to protrude from a position overlapping at least one of the first hole portion 211 and the second hole portion 221 in the internal space of the base through-hole 40 as viewed from the first direction (Z-axis direction), there is a possibility that a portion of the bonding member 23 forming the third hole portion 231 may peel off and enter the first hole portion 211 and the second hole portion 221 when a thermally conductive gas, a lift pin, or the like moves through the base through-hole 40. By setting the hole diameter R3 of the third hole portion 231 to be equal to or greater than the hole diameter R1 of the first hole portion 211 and the hole diameter R2 of the second hole portion 221, the occurrence of such a situation is suppressed. Furthermore, by forming the hole diameter R3 of the third hole portion 231 in this manner, components such as the lift pin and the power supply terminal 91 can be easily inserted into the base through-hole 40 without interfering with the bonding member 23. In this case, it is more preferable that the hole diameter R2 of the second hole portion 221 is equal to or larger than the hole diameter R1 of the first hole portion 211. By doing so, when components such as lift pins and power supply terminals 91 are inserted from below into the base through-hole 40 formed by the first hole portion 211, the second hole portion 221, and the third hole portion 231, the components are prevented from getting caught on the edges of the second hole portion 221. This makes it easier to insert the components into the base through-hole 40.

[0054] In the first embodiment, the central axes L1, L2, and L3 are disposed at different positions from one another when viewed in the first direction (Z-axis direction). In this regard, it is sufficient that at least one of the central axes L1, L2, and L3 is disposed at a different position from the other central axes when viewed in the first direction. For example, the central axes L2 and L3 may be disposed at the same position when viewed in the first direction, and the central axis L1 may be disposed at a different position from the central axes L2 and L3 when viewed in the first direction. The central axes L1 and L3 may be disposed at the same position when viewed in the first direction, and the central axis L2 may be disposed at a different position from the central axes L1 and L3 when viewed in the first direction. The central axes L1 and L2 may be disposed at the same position when viewed in the first direction, and the central axis L3 may be disposed at a different position from the central axes L1 and L2 when viewed in the first direction. As a result, when the first hole portion 211, the second hole portion 221, and the third hole portion 231 are viewed in the first direction, a part of the member constituting one of the first hole portion 211, the second hole portion 221, and the third hole portion 231 is disposed inside the other hole portion, thereby improving the thermal conductivity inside the base through-hole 40.

[0055] The first upper hole 211A, the first lower hole 211B, the second upper hole 221A, the second lower hole 221B, the third upper hole 231A, and the third lower hole 231B may be formed in a shape other than a circle, such as an ellipse or a polygon. The hole diameter of the first upper hole 211A and the hole diameter of the first lower hole 211B may be the same or different. The hole diameter of the second upper hole 221A and the hole diameter of the second lower hole 221B may be the same or different. The hole diameter of the third upper hole 231A and the hole diameter of the third lower hole 231B may be the same or different.

[0056] Furthermore, the first upper hole 211A and the first lower hole 211B may be arranged at different positions when viewed from the first direction (Z-axis direction), and the first hole 211 may be formed so that the central axis L1 extends obliquely and not orthogonal to the fourth surface S4. The second upper hole 221A and the second lower hole 221B may be arranged at different positions when viewed from the first direction, and the second hole 221 may be formed so that the central axis L2 extends obliquely and not orthogonal to the fourth surface S4. The third upper hole 231A and the third lower hole 231B may be arranged at different positions when viewed from the first direction, and the third hole 231 may be formed so that the central axis L3 extends obliquely and not orthogonal to the third surface S3 and the fourth surface S4. In other words, the first direction is not limited to the up-down direction orthogonal to the third surface S3 and the fourth surface S4, but may be a direction obliquely intersecting the third surface S3 and the fourth surface S4.

[0057] 5, the detailed configuration of the holding device through hole 80 or the holding device non-through hole 90 in the holding device 1 will be described. A fourth upper hole 52A, which is a circular hole, is formed in the first surface S1 of the plate-shaped member 10. A fourth lower hole 52B, which is a circular hole, is formed in the second surface S2. The fourth upper hole 52A and the fourth lower hole 52B are arranged at approximately the same position when viewed in the first direction (Z-axis direction). The fourth upper hole 52A and the fourth lower hole 52B are connected to each other, thereby forming a through hole 52 that penetrates the plate-shaped member 10 in the first direction. In other words, the through hole 52 is a cylindrical hole that extends in the first direction inside the plate-shaped member 10 so as to be perpendicular to the first surface S1 and the second surface S2.

[0058] The plate-shaped member 10 also has a cylindrical non-through hole portion 53 extending upward from a fourth lower hole portion 52B formed in the second surface S2 and extending in a first direction through the interior of the plate-shaped member 10. The non-through hole portion 53 does not penetrate the plate-shaped member 10 in the first direction, but is recessed from the second surface S2 toward the first surface S1. Hereinafter, the through hole portion 52 and the non-through hole portion 53 will be collectively referred to as a fourth hole portion 55. That is, the fourth hole portion 55 includes the through hole portion 52 extending from the fourth lower hole portion 52B formed in the second surface S2 toward the first surface S1 and penetrating the plate-shaped member 10 in the first direction, and the non-through hole portion 53 recessed from the fourth lower hole portion 52B toward the first surface S1 but not penetrating the plate-shaped member 10 in the first direction. A terminal connection portion 92 is disposed above the non-through hole portion 53. The terminal connection portion 92 is electrically connected to the lower end of a via 93 that is connected to the chuck electrode 51 and extends downward from the chuck electrode 51. The terminal connection portion 92 is electrically connected to the upper end of a power supply terminal 91 that is housed inside the non-through hole portion 53. In this manner, the central axis L4 of the fourth hole portion 55 extends in the first direction. The central axis L4 is an example of a fourth central axis.

[0059] A fifth lower hole 32B is formed on the base member 20 side of the adhesive layer 30 at a position facing the second upper hole 221A formed in the upper surface 22A of the second member 22 of the base member 20. A fifth upper hole 32A is formed on the plate-like member 10 side of the adhesive layer 30 at a position facing the fourth lower hole 52B formed in the second surface S2 of the plate-like member 10. The fifth upper hole 32A and the fifth lower hole 32B are arranged at approximately the same position in the upper and lower parts of the adhesive layer 30 when viewed in the first direction (Z-axis direction). The fifth hole 32 formed by connecting the fifth upper hole 32A and the fifth lower hole 32B is a cylindrical hole extending in the first direction. In other words, the central axis L5 of the fifth hole 32 extends in the first direction. The fifth hole portion 32 is formed in the adhesive layer 30 so as to be continuous with the second hole portion 221 and the fourth hole portion 55. The central axis L5 is an example of a fifth central axis.

[0060] The fifth hole portion 32 and the through hole portion 52 are connected to each other, forming a hole portion that penetrates the adhesive layer 30 and the plate-shaped member 10 in the first direction (Z-axis direction). This hole portion is referred to as the plate-shaped member through hole 60. The fifth hole portion 32 and the non-through hole portion 53 are connected to each other, forming a hole portion that penetrates the adhesive layer 30 in the first direction and extends inside the plate-shaped member 10 in the first direction. This hole portion is referred to as the plate-shaped member non-through hole 70. The plate-shaped member through hole 60 and the base through hole 40 are connected to each other, forming a holding device through hole 80 that penetrates the holding device 1 in the first direction. As described above, the holding device through hole 80 functions as a gas hole or a lift pin hole. The plate-shaped member non-through hole 70 and the base through hole 40 are connected to each other, forming a holding device non-through hole 90 that extends inside the holding device 1 in the first direction. As described above, the holding device non-through hole 90 functions as a terminal hole.

[0061] The diameter of the fifth hole portion 32 formed in the adhesive layer 30 is preferably equal to or larger than the diameter of the fourth hole portion 55. This prevents a portion of the adhesive layer 30 from being disposed so as to protrude into the internal spaces of the holding device through-hole 80 and the holding device non-through-hole 90. Therefore, when a thermally conductive gas or a lift pin moves inside the holding device through-hole 80 or when a power supply terminal 91 is disposed inside the holding device non-through-hole 90, a portion of the adhesive layer 30 is prevented from being torn off and entering the fourth hole portion 55 or the base through-hole 40.

[0062] The holding device through hole 80 will be described as an example. As shown in FIG. 5 , in the plate-like member through hole 60 that forms the holding device through hole 80, the central axis L4 of the through hole portion 52 of the plate-like member 10 and the central axis L5 of the fifth hole portion 32 of the adhesive layer 30 are disposed at different positions from each other when viewed in the first direction (Z-axis direction). That is, the central axis L4 and the central axis L5 extend parallel to each other in the plate-like member through hole 60 and are disposed without overlapping. Furthermore, in the holding device through hole 80, the central axis L1 of the first hole portion 211, the central axis L2 of the second hole portion 221, the central axis L3 of the third hole portion 231, the central axis L4 of the through hole portion 52, and the central axis L5 of the fifth hole portion 32 are disposed at different positions from each other when viewed in the first direction. Furthermore, the central axes L1, L2, L3, L4, and L5 extend parallel to each other in the holding device through hole 80 and are disposed without overlapping.

[0063] In this case, by arranging a part of the first member 21 forming the first hole portion 211 (the peripheral portion of the first hole portion 211), a part of the second member 22 forming the second hole portion 221 (the peripheral portion of the second hole portion 221), a part of the plate-like member 10 forming the through hole portion 52 (the peripheral portion of the through hole portion 52), and the like in the space inside the holding device through hole 80, it becomes possible to conduct heat to the space inside the holding device through hole 80 via these. This improves the thermal conductivity inside the holding device through hole 80 compared to, for example, a case where the central axes of the holes are arranged at the same position when viewed in the first direction. Therefore, it is possible to prevent the temperature of the portion of the plate-like member 10 where the first hole portion 211 is formed and its surrounding portion from being different from the temperature of other portions.

[0064] In the holding device through hole 80, the central axes L1, L2, L3, L4, and L5 are located at different positions from one another when viewed in the first direction (Z-axis direction). In this regard, it is sufficient that at least one of the central axes L1, L2, and L3 and at least one of the central axes L4 and L5 are located at different positions when viewed in the first direction. That is, it is sufficient that any of the central axis L1 of the first hole portion 211 of the first member 21, the central axis L2 of the second hole portion 221 of the second member 22, and the central axis L3 of the third hole portion 231 of the joining member 23, which form the base through hole 40, and any of the central axis L4 of the through hole portion 52 and the central axis L5 of the fifth hole portion 32, which form the plate-like member through hole 60, are located at different positions when viewed in the first direction. As a result, when the holding device through hole 80 is viewed in the first direction, at least one of a portion of the member forming the base through hole 40 and a portion of the member forming the plate-shaped member through hole 60 is arranged inside the holding device through hole 80, thereby improving thermal conductivity inside the holding device through hole 80.

[0065] 5, in the plate-like member non-through hole 70 forming the holding device non-through hole 90, the central axis L4 of the non-through hole portion 53 of the plate-like member 10 and the central axis L5 of the fifth hole portion 32 of the adhesive layer 30 are disposed at different positions when viewed in the first direction (Z-axis direction), similar to the holding device through hole 80. Furthermore, in the holding device non-through hole 90, the central axis L2 of the second hole portion 221 and the central axis L4 of the non-through hole portion 53 are disposed at the same position when viewed in the first direction, but the central axis L5 of the fifth hole portion 32 is disposed at a different position from the central axis L2 and the central axis L5 when viewed in the first direction.

[0066] In this case, by arranging at least one of a part of the second member 22 and a part of the member forming the plate-shaped member non-through hole 70 at a position in the internal space of the holding device non-through hole 90 where the base through hole 40 and the plate-shaped member non-through hole 70 are connected, it becomes possible to conduct heat to the internal space of the holding device non-through hole 90 via them. This improves the thermal conductivity inside the holding device non-through hole 90 compared to when, for example, the central axis L2 and the central axis L5 are arranged at the same position when viewed in the first direction, and prevents the temperature of the portion of the plate-shaped member 10 around the holding device non-through hole 90 from being different from the temperature of other portions.

[0067] In the retaining device non-through hole 90, the central axis L2 and the central axis L4 are disposed at the same position as viewed in the first direction (Z-axis direction), and the central axis L5 is disposed at a different position from the central axis L2 and the central axis L4 as viewed in the first direction. In this regard, it is sufficient that at least one of the central axes L2, L4, and L5 and the other central axes are disposed at different positions as viewed in the first direction. For example, the central axis L2 and the central axis L5 may be disposed at the same position as viewed in the first direction, and the central axis L4 may be disposed at a different position from the central axis L2 and the central axis L5 as viewed in the first direction. The central axis L4 and the central axis L5 may be disposed at the same position as viewed in the first direction, and the central axis L2 may be disposed at a different position from the central axis L4 and the central axis L5 as viewed in the first direction. Furthermore, the central axis L2, the central axis L4, and the central axis L5 may be disposed at different positions as viewed in the first direction. That is, it is only necessary that the central axis L2 of the second hole portion 221 of the base through-hole 40 that is continuous with the holding device through-hole 80, and at least one of the central axis L4 of the non-through hole portion 53 that forms the plate-shaped member non-through hole 70 and the central axis L5 of the fifth hole portion 32 are arranged at different positions when viewed in the first direction. This allows at least one of a part of the second member 22 and a part of the member that forms the plate-shaped member non-through hole 70 to be arranged at a position in the internal space of the holding device non-through hole 90 where the base through-hole 40 and the plate-shaped member non-through hole 70 are continuous, thereby improving thermal conductivity inside the holding device non-through hole 90.

[0068] The arrangement of the central axes L1 to L5 inside the retaining device through-hole 80 may be the same as the arrangement of the central axes L1 to L5 inside the retaining device non-through-hole 90. The arrangement of the central axes L1 to L5 inside the retaining device non-through-hole 90 may be the same as the arrangement of the central axes L1 to L5 inside the retaining device through-hole 80. Furthermore, the fourth upper hole portion 52A, the fourth lower hole portion 52B, the fifth upper hole portion 32A, and the fifth lower hole portion 32B may be formed in a shape other than a circle, such as an elliptical shape or a polygonal shape. The diameter of the fourth upper hole portion 52A and the diameter of the fourth lower hole portion 52B may be the same or different. The diameter of the fifth upper hole portion 32A and the diameter of the fifth lower hole portion 32B may be the same or different.

[0069] As described above, the holding device 1 includes a base member 20 having a flow path 28 formed therein. The base member 20 includes a first member 21, a second member 22 that is stacked on the first member 21 in the first direction (Z-axis direction), and a joining member 23 that joins the first member 21 and the second member 22. The first member 21 is formed with a first hole portion 211 that penetrates the first member 21 in the first direction. The second member 22 is formed with a second hole portion 221 that penetrates the second member 22 in the first direction. The joining member 23 is formed with a third hole portion 231 that penetrates the joining member 23 in the first direction and is connected to the first hole portion 211 and the second hole portion 221. At least one of the central axis L1, which is the central axis of the first hole portion 211, the central axis L2, which is the central axis of the second hole portion 221, and the central axis L3, which is the central axis of the third hole portion 231, and the other central axes are arranged at different positions when viewed in the first direction.

[0070] At least one of the central axes L1, L2, and L3 is disposed at a different position from the other central axes when viewed in the first direction. In this case, a part of a member constituting another hole portion, the other hole portion having a different central axis from any one of the first hole portion 211, the second hole portion 221, and the third hole portion 231, is disposed in the internal space of the base through hole 40, which is a single hole portion formed by connecting the first hole portion 211, the second hole portion 221, and the third hole portion 231. For this reason, heat is conducted from the internal spaces of the first hole portion 211, the second hole portion 221, and the third hole portion 231 via the part of the member disposed in the internal space of the base through hole 40. As a result, the temperature gradient in the space inside the base through-hole 40 formed by the connection of the holes becomes gentler than when the central axes L1, L2, L3 of the first hole 211, the second hole 221, and the third hole 231 are arranged at the same position when viewed in the first direction, and the temperature distribution throughout the base member 20 becomes more uniform. In this way, the holding device 1 can make the temperature distribution of the wafer W uniform.

[0071] In the base member 20, the spatial regions formed inside the first hole portion 211, the second hole portion 221, and the third hole portion 231 are arranged so as to overlap with each other when viewed in the first direction.

[0072] In this case, the first hole 211, the second hole 221, and the third hole 231 form the base through hole 40 that penetrates the base member 20 in the first direction, and the formed base through hole 40 can be used without hindrance for purposes such as a terminal hole, a gas hole, etc. Also, the thermal conductivity in the portion of the base member 20 where such a base through hole 40 is formed is improved.

[0073] The hole diameter R3 of the third hole portion 231 is equal to or larger than the hole diameter R1 of the first hole portion 211 and the hole diameter R2 of the second hole portion 221.

[0074] In this case, it is possible to prevent a portion of the joining member 23 forming the third hole portion 231 from peeling off and entering the first hole portion 211 and the second hole portion 221. Furthermore, it is possible to prevent the joining member 23 forming the third hole portion 231 from being disposed inside the first hole portion 211 and the second hole portion 221, which makes it easier to insert other components such as the power supply terminal 91 into the base through hole 40 formed by the first hole portion 211, the second hole portion 221, and the third hole portion 231. In this case, it is more preferable that the hole diameter R2 of the second hole portion 221 is equal to or greater than the hole diameter R1 of the first hole portion 211. This makes it easier to insert other components such as the power supply terminal 91 into the base through hole 40.

[0075] The holding device 1 includes a plate-like member 10 having a first surface S1 for holding the wafer W and a second surface S2 opposite the first surface S1, and stacked in a first direction on a second member 22 of the base member 20 with the second surface S2 facing the base member 20, and an adhesive layer 30 for bonding the second surface S2 of the plate-like member 10 to the second member 22 of the base member 20.

[0076] Since the temperature in the base member 20 is made uniform, the temperature of the plate-shaped member 10 is made uniform by heat transfer from the base member 20 to the plate-shaped member 10 via the adhesive layer 30. This makes it possible to make the temperature of the wafer W held on the first surface S1 of the plate-shaped member 10 uniform.

[0077] The plate-shaped member 10 has fourth hole portions 55 formed therein that are recessed at least from the second surface S2 toward the first surface S1 of the plate-shaped member 10. The fourth hole portions 55 include through-hole portions 52 and non-through-hole portions 53. The adhesive layer 30 has fifth hole portions 32 formed therein that penetrate the adhesive layer 30 in the first direction and are connected to the second hole portions 221 and the fourth hole portions 55. The central axis of the fourth hole portions 55 is defined as central axis L4, and the central axis of the fifth hole portions 32 is defined as central axis L5. At least one of the central axis L1, central axis L2, and central axis L3 and at least one of the central axis L4 and central axis L5 are disposed at different positions when viewed in the first direction.

[0078] In this case, the base through hole 40 formed by the first hole portion 211, the second hole portion 221, and the third hole portion 231, which penetrates the base member 20 in the first direction, is connected to the plate-shaped member through hole 60 or the plate-shaped member non-through hole 70 formed by the fourth hole portion 55 and the fifth hole portion 32, which extends in the first direction, to form the holder through hole 80 or the holder non-through hole 90. At least one of the central axis L1, the central axis L2, and the central axis L3 and at least one of the central axis L4 and the central axis L5 are arranged in different positions when viewed in the first direction, so that at least a portion of the member forming the first hole portion 211, the second hole portion 221, and the third hole portion 231 is arranged in the internal space of the holder through hole 80 or the holder non-through hole 90. Therefore, heat is conducted from the internal space of each hole portion via a portion of the member arranged in the internal space of the holder through hole 80 or the holder non-through hole 90. This improves the thermal conductivity of the internal space of the holding device through hole 80 or the holding device non-through hole 90 formed by the connection of each hole portion compared to when the central axes of the first hole portion 211, the second hole portion 221, the third hole portion 231, the fourth hole portion 55 and the fifth hole portion 32 are arranged in the same position when viewed in the first direction.

[0079] The plate-shaped member 10 has formed therein fourth hole portions 55 (through hole portions 52 and non-through hole portions 53) that are recessed at least from the second surface S2 toward the first surface S1 of the plate-shaped member 10. The adhesive layer 30 has formed therein fifth hole portions 32 that penetrate the adhesive layer 30 in the first direction and are connected to the second hole portions 221 and the fourth hole portions 55. The central axis of the fourth hole portions 55 is defined as central axis L4, and the central axis of the fifth hole portions 32 is defined as central axis L5. At least one of the central axes L2, L4, and L5 is located at a different position from the other central axes when viewed in the first direction.

[0080] In this case, the base through hole 40, which is formed by the first hole portion 211, the second hole portion 221, and the third hole portion 231 and which penetrates the base member 20 in the first direction, and the plate-shaped member through hole 60 or the plate-shaped member non-through hole 70, which is formed by the fourth hole portion 55 and the fifth hole portion 32 and extends in the first direction, are connected to form the holder through hole 80 or the holder non-through hole 90. Since at least one of the central axis L2, the central axis L4, and the central axis L5 is arranged at a different position when viewed in the first direction, at least one of a part of the second member 22 and a part of the member forming the plate-shaped member through hole 60 or the plate-shaped member non-through hole 70 is arranged at a position within the space inside the holder through hole 80 or the holder non-through hole 90 where the base through hole 40 and the plate-shaped member through hole 60 or the plate-shaped member non-through hole 70 are connected to each other. For this reason, heat is conducted in the internal space of each hole portion via a part of the member arranged in the internal space of the holding device through hole 80 or the holding device non-through hole 90. This improves the thermal conductivity of the internal space of the holding device through hole 80 or the holding device non-through hole 90 formed by the connection of the hole portions compared to when the central axes of the second hole portion 221, the fourth hole portion 55, and the fifth hole portion 32 are arranged in the same position when viewed in the first direction.

[0081] <Details of the Modification of the First Embodiment of the Present Disclosure> Next, a modified example of the first embodiment of the present disclosure will be described with reference to FIG. 6 . When a flow path 28 is formed inside the second member 22 of the base member 20 as in the first embodiment, when the heat medium flows inside the flow path 28, the heat of the heat medium is transferred to the second member 22. Although the heat of the heat medium is transferred to some parts of the joining member 23 from the bottom surface of the flow path 28, this has little effect, and the heat of the heat medium is mainly transferred via the second member 22 that is in contact with the joining member 23. The heat of the heat medium is transferred to the first member 21 via the joining member 23. Therefore, the heat of the heat medium flowing through the flow path 28 is more easily transferred to the second hole 221 formed in the second member 22 than to the first hole 211 and the third hole 231 formed in the first member 21 and the joining member 23, in which the flow path 28 is not formed. In addition, "a flow path 28 is formed inside the second member 22" means that the side wall of the flow path 28 (the boundary between the flow path 28 and the second member 22, which extends in the Z-axis direction) is formed by the second member 22.

[0082] Here, the closer a portion of each of the first member 21, the second member 22, and the joining member 23 constituting the base member 20 is to the flow path 28, the more easily the temperature of the heat medium flowing through the flow path 28 is transferred to that portion. Therefore, it is preferable that at least one of the first hole portion 211 formed in the first member 21 of the base member 20 in which the flow path 28 is not formed and the third hole portion 231 formed in the joining member 23 be provided closer to the flow path 28 as viewed in the first direction (Z-axis direction) than the second hole portion 221 of the second member 22 in which the flow path 28 is formed. In this case, the temperatures of the internal spaces of the first hole portion 211 and the third hole portion 231 can be made closer to the temperature of the heat medium, and the temperature of the entire internal space of the base through-hole 40 can be made uniform.

[0083] In particular, when multiple base through holes 40 are formed in the base member 20, the distance between each base through hole 40 and the flow path 28 varies. For each base through hole 40, it is preferable that at least one of the first hole portion 211 formed in the first member 21 in which the flow path 28 is not formed and the third hole portion 231 formed in the joining member 23 is provided closer to the flow path 28 as viewed in the first direction (Z-axis direction) than the second hole portion 221 in the second member 22 in which the flow path 28 is formed. This prevents the temperature of the portion of the base member 20 in which the base through hole 40 is formed and its surrounding portion from being different from the temperature of other portions. This allows the temperature of the entire base member 20 to be uniform.

[0084] Specifically, as shown in Fig. 6(A), the edge portions of the first hole portion 211 and the third hole portion 231 may be provided at positions closer to the flow path 28 as viewed in the first direction (Z-axis direction) than the edge portions of the second hole portion 221. In this case, the edge portions of the first hole portion 211 and the third hole portion 231 may be provided at the same positions as viewed in the first direction, as shown in Fig. 6(A).

[0085] In this case, as shown in Fig. 6(B), of the respective edges of the first hole portion 211 and the third hole portion 231, the edge portion of the third hole portion 231 may be provided at a position closer to the flow path 28 as viewed in the first direction (Z-axis direction) than the edge portion of the second hole portion 221. In this case, as shown in Fig. 6(B), the edge portion of the first hole portion 211 may be provided at the same position as the edge portion of the second hole portion 221 as viewed in the first direction. Furthermore, the edge portion of the first hole portion 211 may be provided at a position closer to the flow path 28 as viewed in the first direction than the edge portion of the second hole portion 221.

[0086] 6(C), of the respective edges of the first hole portion 211 and the third hole portion 231, the edge portion of the first hole portion 211 may be provided at a position closer to the flow path 28 as viewed in the first direction (Z-axis direction) than the edge portion of the second hole portion 221. In this case, the edge portion of the third hole portion 231 may be provided at the same position as the edge portion of the second hole portion 221 as viewed in the first direction, as shown in FIG. 6(C). The edge portion of the third hole portion 231 may be provided at a position closer to the flow path 28 as viewed in the first direction than the edge portion of the second hole portion 221.

[0087] <Details of the second embodiment of the present disclosure> Next, a base member 120 according to a second embodiment of the present disclosure will be described with reference to Fig. 7. In the second embodiment, the same components as those in the first embodiment are designated by the same reference numerals, and redundant descriptions of the structure, action, and effect will be omitted.

[0088] The base member 120 according to the second embodiment includes a first member 210 and a second member 220. The first member 210 and the second member 220 are joined by a joining member 23 disposed between the first member 210 and the second member 220. A groove recessed from the upper surface 21A toward the lower surface 21B is formed in the first member 210, thereby forming a flow path 128 inside the first member 210 through which a heat transfer medium can flow. Note that "the flow path 128 is formed inside the first member 210" means that a side wall of the flow path 128 (a boundary between the flow path 128 and the first member 210, which extends in the Z-axis direction) is formed by the first member 210.

[0089] In this case, when the heat medium flows inside the flow path 128, the heat of the heat medium is transferred to the first member 210. Although the heat of the heat medium is transferred to some parts of the joining member 23 from the upper surface of the flow path 128, the influence of this is small, and the heat of the heat medium is mainly transferred via the first member 210 that is in contact with the joining member 23. The heat of the heat medium is transferred to the second member 220 via the joining member 23. For this reason, the heat of the heat medium flowing through the flow path 128 is more easily transferred to the first hole 211 formed in the first member 210 than to the second hole 221 and the third hole 231 formed in the second member 220 and the joining member 23 in which the flow path 128 is not formed. Therefore, it is preferable that at least one of the second hole portion 221 formed in the second member 220 of the base member 120 in which the flow path 128 is not formed and the third hole portion 231 formed in the joining member 23 be provided closer to the flow path 128 as viewed in the first direction (Z-axis direction) than the first hole portion 211 of the first member 210 in which the flow path 128 is formed. In this case, the temperature of the internal space of the second hole portion 221 and the third hole portion 231 can be made closer to the temperature of the heat medium, thereby making the temperature uniform throughout the internal space of the base through-hole 40. When multiple base through-holes 40 are formed in the base member 120, it is preferable that each of the base through-holes 40 is formed in this manner. This makes it possible to make the temperature uniform throughout the base member 120.

[0090] Specifically, as shown in Fig. 7(A), the edge portions of the second hole portion 221 and the third hole portion 231 may be provided at positions closer to the flow path 128 as viewed in the first direction (Z-axis direction) than the edge portion of the first hole portion 211. In this case, the edge portions of the second hole portion 221 and the third hole portion 231 may be provided at the same position as viewed in the first direction, as shown in Fig. 7(A).

[0091] In this case, as shown in Fig. 7(B), of the respective edges of the second hole portion 221 and the third hole portion 231, the edge portion of the third hole portion 231 may be provided at a position closer to the flow path 128 as viewed in the first direction (Z-axis direction) than the edge portion of the first hole portion 211. In this case, as shown in Fig. 7(B), the edge portion of the second hole portion 221 may be provided at the same position as the edge portion of the first hole portion 211 as viewed in the first direction. Furthermore, the edge portion of the second hole portion 221 may be provided at a position closer to the flow path 128 as viewed in the first direction than the edge portion of the first hole portion 211.

[0092] 7(C), of the respective edge portions of the second hole portion 221 and the third hole portion 231, the edge portion of the second hole portion 221 may be provided at a position closer to the flow path 128 as viewed in the first direction (Z-axis direction) than the edge portion of the first hole portion 211. In this case, the edge portion of the third hole portion 231 may be provided at the same position as the edge portion of the first hole portion 211 as viewed in the first direction, as shown in FIG. 7(C). Furthermore, the edge portion of the third hole portion 231 may be provided at a position closer to the flow path 128 as viewed in the first direction than the edge portion of the first hole portion 211.

[0093] Although not shown, a flow path corresponding to the flow path 28 in the first embodiment may be formed inside the joining member 23, rather than inside the first member 21 and the second member 220. In this case, it is preferable that at least one of the first hole portion 211 formed in the first member 21 in which no flow path is formed and the second hole portion 221 formed in the second member 220 is provided closer to the flow path as viewed in the first direction (Z-axis direction) than the third hole portion 231 of the joining member 23 in which the flow path is formed.

[0094] As described above, the flow paths 28, 128 are formed in any one of the first members 21, 210, the second members 22, 220, and the joining member 23, and at least one of the first hole portion 211, the second hole portion 221, and the third hole portion 231 formed in the member in which the flow paths 28, 128 are not formed is located closer to the flow path when viewed in the first direction than the hole portion formed in the member in which the flow paths 28, 128 are formed.

[0095] When the heat medium flows inside the flow passages 28, 128, the temperature of the heat medium is more easily transferred to the first members 21, 210, the second members 22, 220, and the joining members 23 that constitute the base member 20, 120, the closer the portions are to the flow passages 28, 128. In the base member 20, 120, at least one of the holes formed in the members in which the flow passages 28, 128 are not formed is provided closer to the flow passages 28, 128 as viewed in the first direction than the holes formed in the members in which the flow passages 28, 128 are formed. This makes it possible to bring the temperature of the internal space of the base through-hole 40 formed by the first hole 211, the second hole 221, and the third hole 231 closer to the temperature of the heat medium than when the first hole 211, the second hole 221, and the third hole 231 are provided at positions the same distance from the flow passages 28, 128.

[0096] <Details of the third embodiment of the present disclosure> Next, a base member 320 according to a third embodiment of the present disclosure will be described with reference to Fig. 8. In the third embodiment, the same components as those in the first and second embodiments are designated by the same reference numerals, and redundant descriptions of the structure, operation, and effects will be omitted.

[0097] A base member 320 according to the third embodiment includes a first member 210 and a second member 220. The first member 210 and the second member 220 are joined by a joining member 230 disposed between the first member 210 and the second member 220. A groove recessed from the upper surface 21A toward the lower surface 21B is formed in the first member 210. The joining member 230 is not disposed in the region between the first member 210 and the second member 220 where the groove is formed in the first member 210. As a result, a flow path 228 through which a heat transfer medium can flow is formed inside the first member 210 and the joining member 230. Note that "the flow path 228 is formed inside the first member 210 and the joining member 230" means that the side wall of the flow path 228 (the boundary between the flow path 228 and the first member 210 and the joining member 230, which extends in the Z-axis direction) is formed by the first member 210 and the joining member 230.

[0098] In this case, when the heat medium flows inside the flow path 228, the heat of the heat medium is transferred to the first member 210 and the joining member 230. Although the heat of the heat medium is transferred to some parts of the second member 220 from the upper surface of the flow path 228, this has little effect, and the heat of the heat medium is mainly transferred via the joining member 230 that contacts the second member 220. For this reason, the heat of the heat medium flowing through the flow path 228 is more easily transferred to the first hole portion 211 formed in the first member 210 and the third hole portion 231 formed in the joining member 230 than to the second hole portion 221 formed in the second member 220 in which the flow path 228 is not formed. Therefore, it is preferable that the second hole portion 221 formed in the second member 220 of the base member 320 in which the flow path 228 is not formed is provided closer to the flow path 228 as viewed in the first direction (Z-axis direction) than the first hole portion 211 of the first member 210 in which the flow path 228 is formed and the third hole portion 231 of the joining member 230. In this case, the temperature of the space inside the second hole portion 221 can be made closer to the temperature of the heat medium, and the temperature of the entire internal space of the base through-hole 40 can be made uniform. When multiple base through-holes 40 are formed in the base member 320, it is preferable that each of the base through-holes 40 is formed in this manner. This makes it possible to make the temperature of the entire base member 320 uniform.

[0099] Specifically, as shown in Fig. 8(A), the edge of the second hole portion 221 may be located closer to the flow path 228 as viewed in the first direction (Z-axis direction) than the edges of the first hole portion 211 and the third hole portion 231. In this case, as shown in Fig. 8(A), the edge of the third hole portion 231 may be located closer to the flow path 228 as viewed in the first direction than the edge of the second hole portion 221, and the edge of the first hole portion 211 may be located farther from the flow path 228 as viewed in the first direction than the edge of the third hole portion 231. Furthermore, although not shown, the edge of the first hole portion 211 may be located closer to the flow path 228 as viewed in the first direction than the edge of the second hole portion 221, and the edge of the third hole portion 231 may be located farther from the flow path 228 as viewed in the first direction than the edge of the first hole portion 211.

[0100] In this case, as shown in Fig. 8(B), the edges of the first hole 211 and the third hole 231 may be provided at the same position when viewed in the first direction (Z-axis direction). As shown in Fig. 8(C), the edges of the second hole 221 and the third hole 231 may be provided at the same position when viewed in the first direction.

[0101] <Details of the Fourth Embodiment of the Present Disclosure> Next, a base member 420 according to a fourth embodiment of the present disclosure will be described with reference to Fig. 9. In the fourth embodiment, the same components as those in the first, second, and third embodiments are designated by the same reference numerals, and redundant descriptions of the structure, operation, and effects will be omitted.

[0102] The base member 420 according to the fourth embodiment includes a first member 21 and a second member 22. The first member 21 and the second member 22 are joined by a joining member 330 disposed between the first member 21 and the second member 22. The second member 22 has a groove recessed from its lower surface 22B toward its upper surface 22A. The joining member 330 is not disposed in the region between the first member 21 and the second member 22 where the groove is formed in the second member 22. As a result, a flow path 328 through which the heat transfer medium can flow is formed inside the second member 22 and the joining member 330. Note that the phrase "the flow path 328 is formed inside the second member 22 and the joining member 330" means that the sidewall of the flow path 328 (the boundary between the flow path 328 and the second member 22 and the joining member 330, and the portion extending in the Z-axis direction) is formed by the second member 22 and the joining member 330.

[0103] In this case, when the heat medium flows inside the flow path 328, the heat of the heat medium is transferred to the second member 22 and the joining member 330. Although the heat of the heat medium is transferred to some parts of the first member 21 from the bottom surface of the flow path 328, this has little effect, and the heat of the heat medium is mainly transferred via the joining member 330 that contacts the first member 21. For this reason, the heat of the heat medium flowing through the flow path 328 is more easily transferred to the second hole portion 221 formed in the second member 22 and the third hole portion 231 formed in the joining member 330 than to the first hole portion 211 formed in the first member 21 in which the flow path 328 is not formed. Therefore, it is preferable that the first hole portion 211 formed in the first member 21 of the base member 420, in which the flow path 228 is not formed, is located closer to the flow path 328 as viewed in the first direction (Z-axis direction) than the second hole portion 221 of the second member 22 in which the flow path 328 is formed and the third hole portion 231 of the joining member 330. In this case, the temperature of the space inside the first hole portion 211 can be made closer to the temperature of the heat medium, and the temperature of the entire internal space of the base through-hole 40 can be made uniform. When multiple base through-holes 40 are formed in the base member 420, it is preferable that each of the base through-holes 40 is formed in this manner. This makes it possible to make the temperature of the entire base member 420 uniform.

[0104] 9(A), the edge of the first hole portion 211 may be located closer to the flow path 328 as viewed in the first direction (Z-axis direction) than the edges of the second hole portion 221 and the third hole portion 231. In this case, as shown in FIG. 9(A), the edge of the third hole portion 231 may be located closer to the flow path 328 as viewed in the first direction than the edge of the first hole portion 211, and the edge of the second hole portion 221 may be located farther from the flow path 328 as viewed in the first direction than the edge of the third hole portion 231. Furthermore, although not shown, the edge of the second hole portion 221 may be located closer to the flow path 328 as viewed in the first direction than the edge of the first hole portion 211, and the edge of the third hole portion 231 may be located farther from the flow path 328 as viewed in the first direction than the edge of the second hole portion 221.

[0105] In this case, as shown in Fig. 9(B), the edges of the second hole 221 and the third hole 231 may be provided at the same position when viewed in the first direction (Z-axis direction). As shown in Fig. 9(C), the edges of the first hole 211 and the third hole 231 may be provided at the same position when viewed in the first direction.

[0106] As described above, the flow paths 228, 328 are formed in any two of the first members 21, 210, the second members 22, 220, and the joining members 230, 330, and the hole portions formed in the members among the first hole portion 211, the second hole portion 221, and the third hole portion 231 in which the flow paths 228, 328 are not formed are located closer to the flow paths 228, 328 when viewed in the first direction than the hole portions formed in the members in which the flow paths 228, 328 are formed.

[0107] When the heat medium flows inside the flow paths 228, 328, the temperature of the heat medium is more easily transferred to the first members 21, 210, the second members 22, 220, and the joining members 230, 330 constituting the base member 320, 420, the closer the portions are to the flow paths 228, 328. In the base member 320, 420, the holes formed in the members in which the flow paths 228, 328 are not formed are located closer to the flow paths 228, 328 as viewed in the first direction than the holes formed in the members in which the flow paths 228, 328 are formed. This allows the temperature of the internal space of the base through-hole 40 formed by the first hole 211, the second hole 221, and the third hole 231 to be closer to the temperature of the heat medium than when the first hole 211, the second hole 221, and the third hole 231 are located at positions the same distance from the flow paths 228, 328.

[0108] <Other embodiments> The present disclosure is not limited to the embodiments described above and in the drawings, and for example, the following embodiments are also included within the technical scope of the present disclosure. Furthermore, various modifications other than those described below can be made without departing from the spirit of the present disclosure.

[0109] (1) When the base through-hole 40 forms a part of the holding device through-hole 80 and the holding device through-hole 80 functions as a gas hole, a porous body, which is a porous, breathable, insulating member, may be disposed somewhere inside the holding device through-hole 80. The porous body may be formed of a ceramic material or the like. By disposing the porous body, even when high-frequency power is applied to the base member 20, 120, 320, 420 and a bias voltage is generated on the wafer W, the occurrence of abnormal discharge in the space extending inside the holding device through-hole 80 in the first direction (Z-axis direction) is reduced. The porous body may be disposed inside the plate-shaped member through-hole 60 or inside the base through-hole 40.

[0110] (2) The first surface S1 of the plate-like member 10 may be provided with a plurality of protrusions for supporting the wafer W.

[0111] (3) An electrode other than the chuck electrode 51, such as an electrode for a heater, may be provided inside the plate-shaped member 10. The holding device non-through hole 90 may be used as a terminal hole in which a terminal is disposed for supplying power to an electrode other than the chuck electrode 51. Furthermore, the plate-shaped member 10 does not necessarily have to include an electrode such as the chuck electrode 51 inside.

[0112] (4) Although not shown, a protective member such as an O-ring may be disposed inside the third hole portion 231 and the fifth hole portion 32 to protect the joining member 230 and the adhesive layer 30.

[0113] (5) The present disclosure can also be applied to holes formed inside the holding device 1 and extending in the first direction, in addition to gas holes, lift pin holes, and terminal holes. [Explanation of symbols]

[0114] 1: Holding device 10: Plate-shaped member 20, 120, 320, 420: Base member 21, 210: First member 22, 220: Second member 23, 230, 330: Joining member 28, 128, 228, 328: Flow path 30: Adhesive layer 32: Fifth hole portion 40: Base through-hole 52: Through-hole portion 53: Non-through-hole portion 55: Fourth hole portion 60: Plate-shaped member through-hole 70: Plate-shaped member non-through-hole 80: Holding device through-hole 90: Holding device non-through-hole 211: First hole portion 221: Second hole portion 231: Third hole portion L1, L2, L3, L4, L5: Central axis R1, R2, R3: Hole diameter S1: First surface S2: Second surface S3: Third surface S4: Fourth surface W: Wafer

Claims

1. A holding device comprising a base member having a flow path formed therein, The base member is A first member; a second member that is overlapped with the first member in a first direction; a joining member that joins the first member and the second member; Equipped with a first hole portion penetrating the first member in the first direction is formed in the first member; a second hole portion penetrating the second member in the first direction is formed in the second member; a third hole portion that penetrates the joining member in the first direction and is connected to the first hole portion and the second hole portion, At least one of a first central axis that is a central axis of the first hole portion, a second central axis that is a central axis of the second hole portion, and a third central axis that is a central axis of the third hole portion is disposed at a different position from the other central axes when viewed in the first direction. holding device.

2. The holding device according to claim 1, wherein the spatial regions formed inside the first hole portion, the second hole portion, and the third hole portion in the base member are arranged to overlap each other when viewed in the first direction.

3. The holding device according to claim 1 , wherein the diameter of the third hole portion is equal to or larger than the diameter of the first hole portion and the diameter of the second hole portion.

4. the flow path is formed in any one of the first member, the second member, and the joining member, At least one of the first hole portion, the second hole portion, and the third hole portion formed in a member in which the flow path is not formed is provided closer to the flow path as viewed in the first direction than a hole portion formed in a member in which the flow path is formed. The retaining device of claim 1 .

5. the flow path is formed in any two of the first member, the second member, and the joining member, Among the first hole portion, the second hole portion, and the third hole portion, the hole portion formed in the member in which the flow path is not formed is provided closer to the flow path as viewed in the first direction than the hole portion formed in the member in which the flow path is formed. The retaining device of claim 1 .

6. a plate-like member having a first surface for holding an object to be processed and a second surface opposite to the first surface, the plate-like member being stacked on the second member of the base member in the first direction with the second surface facing the base member; an adhesive layer that bonds the second surface of the plate-like member and the second member of the base member; The retaining device of claim 1 , comprising:

7. a fourth hole portion recessed at least from the second surface toward the first surface of the plate-like member is formed in the plate-like member; a fifth hole portion that penetrates the adhesive layer in the first direction and is connected to the second hole portion and the fourth hole portion is formed in the adhesive layer; When the central axis of the fourth hole portion is defined as a fourth central axis and the central axis of the fifth hole portion is defined as a fifth central axis, 7. The holding device according to claim 6, wherein at least one of the first center axis, the second center axis, and the third center axis and at least one of the fourth center axis and the fifth center axis are arranged at different positions when viewed in the first direction.

8. a fourth hole portion recessed at least from the second surface toward the first surface of the plate-like member is formed in the plate-like member; a fifth hole portion that penetrates the adhesive layer in the first direction and is connected to the second hole portion and the fourth hole portion is formed in the adhesive layer; When the central axis of the fourth hole portion is defined as a fourth central axis and the central axis of the fifth hole portion is defined as a fifth central axis, The holding device according to claim 6 , wherein at least one of the second central axis, the fourth central axis, and the fifth central axis is disposed at a different position from the other central axes when viewed in the first direction.

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