Holding device

Abstract

To provide a holding device that can suppress corrosion of the bonding layer. [Solution] The holding device 1 comprises a plate-shaped member 10 having a first surface S1 and a second surface S2 located on the opposite side of the first surface, a base member having a third surface S3 positioned opposite to the second surface S2 and a fourth surface S4 located on the opposite side of the third surface S3, and a bonding layer 30 positioned between the second surface S2 and the third surface S3 to join the second surface S2 and the third surface S3. The base member 20 comprises a bonding layer arrangement portion 21 on which the bonding layer 30 is arranged, an outer peripheral flow path 23 which is a gas flow path provided on the outer peripheral side of the bonding layer arrangement portion 21 and formed in the shape of a groove so as to surround the bonding layer arrangement portion 21, and a penetrating flow path 24 which is a gas flow path extending from the outer peripheral flow path 23 toward the fourth surface S4 and formed to penetrate the base member 20 in the thickness direction.

Description

Technical Field

[0001] This disclosure relates to a holding device.

Background Art

[0002] As an example of a holding device for holding a wafer during semiconductor manufacturing, an electrostatic chuck described in Patent Document 1 is known. This type of electrostatic chuck includes a ceramic substrate forming a chuck body and a base member for cooling the ceramic substrate, and can hold a wafer on the surface of the ceramic substrate by electrostatic attraction. The ceramic substrate and the base member are joined to each other by a bonding layer interposed therebetween. Such an electrostatic chuck is attached inside a processing chamber of a semiconductor manufacturing apparatus and is used to perform various processes such as film formation and etching on the wafer using plasma.

[0003] A refrigerant flow path is provided inside the base member, and by flowing refrigerant through this refrigerant flow path, cooling of plasma heat is performed. Specifically, the base member is cooled, and the holding substrate is cooled by heat transfer (heat extraction) between the base member and the holding substrate through the bonding layer. As a result, the wafer held on the surface of the ceramic substrate is cooled. Patent Document 1 discloses an electrostatic chuck provided with a cooling gas passage for supplying a cooling gas for cooling an O-ring that protects the bonding layer between the ceramic substrate and the base member in addition to such a refrigerant passage.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In plasma processing, the inside of the processing chamber is subjected to a process gas atmosphere at a predetermined pressure. Highly reactive gases are sometimes used as the process gas. If the bonding layer of an electrostatic chuck is exposed to the reactive gas and corrosion progresses, problems may occur such as a loss of heat transfer performance between the base member and the holding substrate, or the corroded bonding layer turning into dust.

[0006] The purpose of this disclosure is to provide a holding device that can suppress corrosion of the bonding layer. [Means for solving the problem]

[0007] The holding device of the present disclosure comprises a plate-shaped member having a first surface and a second surface located opposite to the first surface; a base member having a third surface disposed opposite to the second surface and a fourth surface located opposite to the third surface; and a bonding layer disposed between the second surface and the third surface and joining the second surface and the third surface, wherein the base member comprises a bonding layer arrangement portion in which the bonding layer is disposed; an outer peripheral flow path which is a gas flow path provided at a position on the outer periphery of the bonding layer arrangement portion and formed in the shape of a groove so as to surround the bonding layer arrangement portion; and a penetrating flow path which is a gas flow path that extends from the outer peripheral flow path toward the fourth surface and is formed to penetrate the base member in the thickness direction. [Effects of the Invention]

[0008] According to this disclosure, a retaining device that can suppress corrosion of the joint layer can be provided. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic diagram illustrating the general configuration of the holding device according to the first embodiment. [Figure 2] Figure 2 is a cross-sectional view obtained by cutting Figure 1 through the XZ plane. [Figure 3] Figure 3 is a plan view of the holding device according to the first embodiment, in which the plate-shaped member is omitted. [Figure 4]Figure 4 is a perspective view of the holding device according to the first embodiment, in which the plate-shaped member is omitted. [Figure 5] Figure 5 is a partial cross-sectional view of the holding device according to the second embodiment, when cut in the XZ plane. [Figure 6] Figure 6 is a partial cross-sectional view of the holding device according to the third embodiment, when cut in the XZ plane. [Figure 7] Figure 7 is a partial cross-sectional view of the holding device according to the fourth embodiment, when cut in the XZ plane. [Figure 8] Figure 8 is a partial cross-sectional view of the holding device according to the fifth embodiment, when cut in the XZ plane. [Figure 9] Figure 9 is a partial cross-sectional view of the holding device according to the sixth embodiment, when cut in the XZ plane. [Figure 10] Figure 10 is a plan view of the holding device according to the sixth embodiment, in which the plate-shaped member is omitted. [Figure 11] Figure 11 is a perspective view of the holding device according to the sixth embodiment, in which the plate-shaped member is omitted. [Figure 12] Figure 12 is a partial cross-sectional view of the holding device according to the seventh embodiment, when cut in the XZ plane. [Figure 13] Figure 13 is a perspective view of the holding device according to the seventh embodiment, in which the plate-shaped member is omitted. [Figure 14] Figure 14 is a partial cross-sectional view of the holding device according to the eighth embodiment, when cut in the XZ plane. [Modes for carrying out the invention]

[0010] First, embodiments of this disclosure will be listed and described. (1) The holding device of the present disclosure comprises a plate-shaped member having a first surface and a second surface located opposite to the first surface; a base member having a third surface disposed opposite to the second surface and a fourth surface located opposite to the third surface; and a bonding layer disposed between the second surface and the third surface and bonding the second surface and the third surface, wherein the base member comprises a bonding layer arrangement portion in which the bonding layer is disposed; an outer peripheral flow path which is a gas flow path provided at a position on the outer periphery of the bonding layer arrangement portion and formed in the shape of a groove so as to surround the bonding layer arrangement portion; and a penetrating flow path which is a gas flow path that extends from the outer peripheral flow path toward the fourth surface and is formed to penetrate the base member in the thickness direction.

[0011] When the inside of the processing chamber is subjected to a reactive gas atmosphere, the holding device according to this disclosure has an outer peripheral channel, so some of the reactive gas from outside the holding device toward the bonding layer enters the outer peripheral channel and accumulates there. The holding device according to this disclosure has a through channel in the outer peripheral channel, so the reactive gas accumulated in the outer peripheral channel can be exhausted from the outer peripheral channel toward the fourth surface via the through channel. Furthermore, the holding device according to this disclosure can reduce the concentration of the reactive gas accumulated in the outer peripheral channel and exhaust the reactive gas accumulated in the outer peripheral channel toward the outside of the outer peripheral channel by supplying an inert gas such as helium through the through channel. In this way, the holding device according to this disclosure can suppress the accumulation of reactive gas in contact with the bonding layer at a high concentration. Therefore, the holding device according to this disclosure can suppress corrosion of the bonding layer.

[0012] (2) The holding device of the present disclosure includes a plate-like member having a first surface and a second surface located on the opposite side of the first surface, a base member having a third surface disposed opposite to the second surface and a fourth surface located on the opposite side of the third surface, and a bonding layer disposed between the second surface and the third surface for bonding the second surface and the third surface. The base member includes a bonding layer arrangement portion where the bonding layer is disposed, a through-flow path that is provided at a position on the outer peripheral side of the bonding layer arrangement portion and is formed to extend from the third surface toward the fourth surface so as to penetrate the base member in the thickness direction, and an outer peripheral convex portion that protrudes from the third surface toward the second surface so as to surround the through-flow path and the bonding layer arrangement portion at a position on the outer peripheral side of the through-flow path.

[0013] When the inside of the processing chamber is set to a reactive gas atmosphere, since the holding device according to the present disclosure is provided with an outer peripheral convex portion, it is possible to block the reactive gas flowing from the outside of the holding device toward the bonding layer. Further, since the holding device according to the present disclosure forms a through-flow path at a position on the outer peripheral side of the base member rather than the bonding layer arrangement portion, it is possible to exhaust the reactive gas staying between the outer peripheral convex portion and the bonding layer arrangement portion toward the fourth surface through the through-flow path. Further, the holding device according to the present disclosure can reduce the concentration of the reactive gas staying between the outer peripheral convex portion and the bonding layer arrangement portion by supplying an inert gas from the through-flow path, and can exhaust the reactive gas staying between the outer peripheral convex portion and the bonding layer arrangement portion so as to be pushed out toward the outer peripheral side from between the outer peripheral convex portion and the second surface to the outside of the holding device. In this way, the holding device according to the present disclosure can suppress the reactive gas from staying in a state of being in contact with the bonding layer at a high concentration. Therefore, the holding device according to the present disclosure can suppress the corrosion of the bonding layer.

[0014] (3) In the holding device according to (2), an outer peripheral flow path, which is a gas flow path formed in a groove shape so as to surround the bonding layer arrangement portion, is formed between the outer peripheral convex portion and the bonding layer arrangement portion, and the through-flow path may be formed to extend from the outer peripheral flow path toward the fourth surface.

[0015] In this case, since the holding device forms an outer peripheral flow path between the outer peripheral convex portion and the bonding layer arrangement portion, the reactive gas that has entered between the outer peripheral convex portion and the bonding layer arrangement portion can be retained in the outer peripheral flow path. Since a through-flow path extends from this outer peripheral flow path toward the fourth surface, the holding device can exhaust the reactive gas retained in the outer peripheral flow path from the outer peripheral flow path toward the fourth surface through the through-flow path. Further, the holding device can supply an inert gas from the through-flow path, thereby reducing the concentration of the reactive gas retained in the outer peripheral flow path and exhausting the reactive gas retained in the outer peripheral flow path so as to extrude it toward the outer peripheral side outside the outer peripheral flow path. Therefore, the holding device can further suppress the corrosion of the bonding layer.

[0016] (4) In the holding device according to any one of (1) to (3), another through-flow path that does not communicate with the through-flow path may be formed at a position on the outer peripheral side of the through-flow path.

[0017] In this case, by exhausting or supplying an inert gas also in the another through-flow path, it is further suppressed that the reactive gas stays in a state of contacting the bonding layer at a high concentration.

[0018] <Details of the First Embodiment of the Present Disclosure> The schematic configuration of the first embodiment of the present disclosure will be described with reference to FIGS. 1 to 4. Note that the present disclosure is not limited to these examples, and is indicated by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims. In the following description, for a plurality of identical members, only some members may be labeled with reference numerals, and the reference numerals of other members may be omitted. In this specification, the positive direction of the Z-axis is the upward direction, the negative direction of the Z-axis is the downward direction, and the XY plane direction is the horizontal direction, and the configuration of the holding device 1 will be described. However, in the actual usage mode of the holding device 1, it may be arranged differently. Further, in this specification, "horizontal" and "parallel" shall also include arrangements in a mode that is substantially recognized as horizontal and parallel.

[0019] The holding device 1 of the first embodiment is an electrostatic chuck capable of adsorbing and holding a workpiece (hereinafter referred to as "wafer W"). The workpiece is a semiconductor wafer, a glass substrate, etc. The electrostatic chuck is installed, for example, inside the processing chamber of a semiconductor manufacturing apparatus (not shown) and used to perform various processes on the wafer W, such as film deposition and etching, using plasma.

[0020] The holding device 1 of the first embodiment comprises a plate-shaped member 10 and a base member 20, as shown in Figure 1. The plate-shaped member 10 and the base member 20 are joined to each other by a bonding layer 30 disposed between the plate-shaped member 10 and the base member 20.

[0021] The plate-shaped member 10 is a plate-shaped member that is approximately circular in shape when viewed in the Z-axis direction and has insulating properties. In the first embodiment, the plate-shaped member 10 has a shape having, for example, a diameter of about 300 mm and a thickness of about 3 mm. The plate-shaped member 10 is formed of ceramics mainly composed of, for example, alumina (Al2O3) or aluminum nitride (AlN). In this specification, "main component" means that the component present in the largest proportion.

[0022] As shown in Figure 2, the plate-shaped member 10 comprises a central portion 10A and a flange portion 10B extending around the outer circumference of the central portion 10A. The central portion 10A constitutes the central part of the plate-shaped member 10 and extends upward from the flange portion 10B. The upper surface of the central portion 10A is the first surface S1 for holding the wafer W. The surface of the plate-shaped member 10 located on the opposite side of the first surface S1 is the second surface S2 shown in Figure 2. The first surface S1 and the second surface S2 are substantially circular surfaces extending in a direction perpendicular to the Z-axis direction (horizontal direction). The first surface S1 is located on the upper side of the plate-shaped member 10, and the second surface S2 is located on the lower side of the plate-shaped member 10, that is, below the central portion 10A and the flange portion 10B. Note that the plate-shaped member 10 may be formed without the flange portion 10B, with the first surface S1 extending over the entire upper surface of the plate-shaped member 10.

[0023] As shown in Figure 2, a chuck electrode 40 made of a conductive material including tungsten, molybdenum, etc., is arranged inside the plate-shaped member 10. The chuck electrode 40 is, for example, planar and substantially parallel to the first surface S1. The chuck electrode 40 is provided with a power supply terminal (not shown), and an electrostatic attraction force is generated when power is supplied to the chuck electrode 40 from an external power source via the power supply terminal. The wafer W is attracted and held on the first surface S1 by this electrostatic attraction force.

[0024] The plate-shaped member 10 with the above configuration can be manufactured, for example, by creating multiple green sheets made of ceramics, processing a predetermined green sheet by forming via holes, filling it with metallizing paste, printing, etc., heat-pressing these green sheets together, cutting or other processing, and then firing them.

[0025] As shown in Figure 1, the base member 20 is a substantially disc-shaped member having a diameter equivalent to that of the plate-shaped member 10. In the first embodiment, the base member 20 has a diameter of about 300 mm and a thickness of about 15 mm to 30 mm. The base member 20 is formed from a metal such as aluminum or an aluminum alloy, a ceramic mainly composed of silicon carbide (SiC), alumina, aluminum nitride, or a composite material of metal and ceramic. When the base member 20 is formed from a metal, it is preferable to form it from an aluminum alloy such as A5052 or A6061, which is easy to shape and has corrosion resistance, or from a pure titanium plate such as TP340. When the base member 20 is made of ceramics, it is preferable that its thermal conductivity is 70 W / m·K or higher. In this case, since the thermal conductivity of the base member 20 is relatively high, the heat exchange efficiency with the refrigerant flowing through the refrigerant flow path 29, which will be described later, is improved.

[0026] In the first embodiment, the base member 20 is made of a sintered ceramic body mainly composed of silicon carbide. If the sintered ceramic body mainly composed of silicon carbide is conductive, the base member 20 can be given the function of an electrode to which a high-frequency voltage for generating plasma is applied. If the base member 20 is made of a non-conductive material, a conductive film may be formed on the surface of the base member 20. This allows the base member 20 to function as an electrode during plasma processing. Similarly, if the base member 20 is made mainly of silicon carbide, a similar conductive film may be formed on the surface of the base member 20.

[0027] As shown in Figure 2, the base member 20 has a third surface S3 located on the plate-shaped member 10 side and a fourth surface S4 located on the opposite side from the third surface S3. The third surface S3 and the fourth surface S4 are both substantially circular surfaces extending in a direction perpendicular to the Z-axis direction (horizontal direction). The third surface S3 is located on the upper side of the base member 20, and the fourth surface S4 is located on the lower side of the base member 20. The third surface S3 is joined to the second surface S2 of the plate-shaped member 10 by a bonding layer 30. The surface roughness (Ra) of the third surface S3 and the fourth surface S4 is preferably about 0.8 μm to 2.0 μm.

[0028] A refrigerant channel 29 is formed inside the base member 20. The refrigerant channel 29 is a channel with a width of approximately 5 mm to 10 mm and a depth of approximately 10 mm, and is formed in a spiral shape in a plan view inside the base member 20. The refrigerant channel 29 is connected to a refrigerant circulation device (not shown). The refrigerant circulation device is configured to circulate the refrigerant through the refrigerant channel 29. A fluorine-based inert liquid, water, etc., is used as the refrigerant. When the refrigerant flows through the refrigerant channel 29, 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 bonding layer 30. As a result, the wafer W held on the first surface S1 of the plate-shaped member 10 is cooled. In this way, the temperature of the wafer W is controlled.

[0029] In recent years, the amount of heat generated by plasma processing has increased, and maintaining the heat transfer performance between the plate-shaped member 10 and the base member 20 is crucial in order to maintain the wafer W temperature at a predetermined temperature. In this embodiment, both the plate-shaped member 10 and the base member 20 are made of ceramic material. In such cases, the thermal conductivity of the plate-shaped member 10 and the base member 20 can be relatively similar, making it easier to maintain the heat transfer performance between the plate-shaped member 10 and the base member 20 via the bonding layer 30. As shown in Figure 2, the refrigerant flow path 29 is formed to be rectangular in the XZ plane cross-section view, but the refrigerant flow path 29 may be formed to have other shapes such as circular or elliptical.

[0030] The base member 20 of the above configuration can be made, for example, by molding ceramic raw material powder by CIP (cold isohydrostatic pressing), degreasing the resulting molded body by holding it at a predetermined temperature, heating the degreased molded body to a high temperature in a nitrogen gas atmosphere or the like, and appropriately molding the sintered body obtained by heating.

[0031] The bonding layer 30 is positioned between the second surface S2 of the plate-shaped member 10 and the third surface S3 of the base member 20. The bonding layer 30 is composed of an adhesive having a predetermined thermal conductivity and thermal expansion properties. As the adhesive constituting the bonding layer 30, an organic resin material or an inorganic adhesive material is used. Organic resin materials include, for example, silicone resin, fluororesin, acrylic resin, and epoxy resin. Inorganic adhesive materials are, for example, mainly composed of ceramics and inorganic polymers. When the bonding layer 30 is composed of an adhesive made of an organic resin material, the thickness T1 of the bonding layer 30 shown in Figure 4 is, for example, about 10 μm to 800 μm.

[0032] The detailed configuration of the base member 20 will be described with reference to Figures 2 to 4. Figure 3 shows the holding device 1 with the plate-shaped member 10 omitted, viewed in the Z-axis direction. The central flat portion of the third surface S3 of the base member 20 is the bonding layer arrangement portion 21 where the bonding layer 30 is placed. Figure 3 shows the state in which the bonding layer 30 is placed over the entire upper side of this bonding layer arrangement portion 21. The portion of the base member 20 that is on the outer periphery of the bonding layer arrangement portion 21 is the outer periphery portion 22. The outer periphery portion 22 extends substantially horizontally below the flange portion 10B of the plate-shaped member 10.

[0033] An outer peripheral channel 23 is formed in the outer peripheral portion 22. As shown in Figures 3 and 4, the outer peripheral channel 23 is a gas flow channel formed as a groove that is recessed in an annular shape on the outer peripheral portion 22, surrounding the bonding layer arrangement portion 21 in a view along the Z axis. As shown in Figures 2 and 4, the outer peripheral channel 23 is formed as a rectangular recess in an XZ plan cross-sectional view, extending from the outer peripheral portion 22 toward the fourth surface S4. There are no particular restrictions on the depth D1 of the outer peripheral channel 23 shown in Figure 2, but in this embodiment, the depth D1 is set to about 1 mm, taking into consideration the ease of gas flow inside the outer peripheral channel 23.

[0034] A through-channel 24, which is a gas channel, is formed in the base member 20, extending from the outer peripheral channel 23 toward the fourth surface S4 and penetrating the base member 20 in its thickness direction. As shown in Figure 3, multiple through-channels 24 are formed at predetermined intervals in the circumferential direction in which the outer peripheral channel 23 extends, at the bottom of the outer peripheral channel 23. A fitting (not shown) is connected to the fourth surface S4 side of the through-channel 24, and a pipe (not shown) is connected to the fitting.

[0035] When the holding device 1 is placed inside the processing chamber and plasma processing is performed on the wafer W held by the holding device 1, the inside of the processing chamber may be subjected to a process gas atmosphere. The outer peripheral channel 23 and the through channel 24 are provided to suppress corrosion of the bonding layer 30 by exposure to the reactive gas when a reactive gas is used as the process gas. Examples of reactive gases used include NF3, Cl2, CF4, CCl4, HF, ClF3, and HCl. When the holding device 1 is placed in a reactive gas atmosphere, the reactive gas flows from the outside of the base member 20 towards the outer peripheral portion 22 of the base member 20, and the reactive gas that has gone towards the outer peripheral portion 22 flows inward through the outer peripheral channel 23. The outer peripheral channel 23 is formed on the base member 20 at a position on the outer periphery of the base member 20, further outward than the bonding layer placement portion 21. Therefore, the base member 20 can prevent the reactive gas flowing from the outer peripheral portion 22 towards the inside of the holding device 1 from coming into contact with the bonding layer 30 by allowing it to accumulate inside the outer peripheral channel 23.

[0036] An exhaust device (not shown) capable of exhausting gas can be connected to the aforementioned piping. In this case, the gas containing reactive gas that has accumulated inside the outer peripheral channel 23 can be drawn in by the exhaust device through the through-channel 24 toward the fourth surface S4 and exhausted to the outside of the base member 20 via the joint and piping. As a result, the gas containing reactive gas is exhausted from inside the outer peripheral channel 23, and the concentration of reactive gas near the bonding layer 30 is reduced. In this way, the accumulation of reactive gas in contact with the bonding layer 30 at a high concentration is suppressed, thereby suppressing corrosion of the bonding layer 30.

[0037] Furthermore, an air supply device (not shown) capable of supplying gas can be connected to the aforementioned piping. In this case, the air supply device can supply an inert gas such as helium to the inside of the outer peripheral flow path 23 through the through-flow path 24 via the piping and fittings. In this case, the reactive gas accumulating inside the outer peripheral flow path 23 is diluted by the inert gas. In addition, by supplying the inert gas to the inside of the outer peripheral flow path 23, the gas containing the reactive gas accumulating inside the outer peripheral flow path 23 is exhausted by being pushed outwards towards the outer periphery of the base member 20. In this way, the accumulation of reactive gas in a high concentration in contact with the bonding layer 30 is suppressed, thereby suppressing corrosion of the bonding layer 30.

[0038] As described above, the holding device 1 comprises a plate-shaped member 10 having a first surface S1 and a second surface S2 located on the opposite side of the first surface S1, a base member 20 having a third surface S3 positioned opposite to the second surface S2 and a fourth surface S4 located on the opposite side of the third surface S3, and a bonding layer 30 positioned between the second surface S2 and the third surface S3 to join the second surface S2 and the third surface S3. The base member 20 comprises a bonding layer arrangement portion 21 on which the bonding layer 30 is arranged, an outer peripheral flow path 23 which is a gas flow path provided on the outer peripheral side of the bonding layer arrangement portion 21 and formed in the shape of a groove so as to surround the bonding layer arrangement portion 21, and a penetrating flow path 24 which is a gas flow path extending from the outer peripheral flow path 23 toward the fourth surface S4 and formed to penetrate the base member 20 in the thickness direction.

[0039] When the inside of the processing chamber is a reactive gas atmosphere, the holding device 1 is equipped with an outer peripheral channel 23, so some of the reactive gas from outside the holding device 1 toward the bonding layer 30 enters the outer peripheral channel 23 and accumulates there. The holding device 1 is equipped with a through channel 24 in the outer peripheral channel 23, so the reactive gas accumulated in the outer peripheral channel 23 can be exhausted from the outer peripheral channel 23 toward the fourth surface S4 via the through channel 24. In addition, the holding device 1 can reduce the concentration of the reactive gas accumulated in the outer peripheral channel 23 by supplying an inert gas such as helium from the through channel 24, and can also exhaust the reactive gas accumulated in the outer peripheral channel 23 by pushing it toward the outer peripheral side toward the outside of the outer peripheral channel 23. In this way, the holding device 1 can suppress the accumulation of reactive gas in contact with the bonding layer 30 at a high concentration. Therefore, the holding device 1 can suppress corrosion of the bonding layer 30.

[0040] <Details of the second embodiment of this disclosure> Next, a holding device 100 according to the second embodiment of this disclosure will be described with reference to Figure 5. In the second embodiment, the same reference numerals are used for the same parts as in the first embodiment, and redundant explanations of the structure, operation, and effect will be omitted.

[0041] As shown in Figure 5, the holding device 100 comprises a plate-shaped member 110, a base member 120, and a bonding layer 130. The plate-shaped member 110 comprises a central portion 110A, a flange portion 110B, and a downward extension portion 110C. The central portion 110A and the flange portion 110B correspond to the central portion 10A and the flange portion 10B of the first embodiment, respectively. The downward extension portion 110C is the portion that extends downward from the flange portion 110B. The second surface S2 of the plate-shaped member 110 is located below the central portion 110A, below the portion of the flange portion 110B that is close to the central portion 110A, and on the inside and below the downward extension portion 110C.

[0042] The base member 120 comprises a bonding layer arrangement portion 121 and an outer peripheral portion 122. The bonding layer arrangement portion 121 constitutes the central part of the base member 120 and extends upward from the outer peripheral portion 122. The downward extension portion 110C of the plate-shaped member 110 is arranged to surround the outside of the outer peripheral end face 121B of the bonding layer arrangement portion 121. In the second embodiment, the bonding layer arrangement portion 121 comprises an upper surface 121A and an outer peripheral end face 121B, and the bonding layer 130 is arranged on the upper side of the upper surface 121A and the outer peripheral end face 121B, respectively. The outer peripheral portion 122 extends below the downward extension portion 110C of the plate-shaped member 110. The plate-shaped member 110 and the base member 120 are joined to each other by the bonding layer 130 arranged between the plate-shaped member 110 and the base member 120.

[0043] An outer peripheral channel 123 is formed in the outer peripheral portion 122 of the base member 120. Although not shown in the figure, the outer peripheral channel 123 is a gas channel formed as a groove that is recessed in an annular shape on the outer peripheral portion 122, surrounding the bonding layer arrangement portion 121 when viewed in the Z-axis direction. As shown in Figure 5, the outer peripheral channel 123 is formed as a rectangular recess in the XZ plan cross-section view, extending from the outer peripheral portion 122 toward the fourth surface S4. The depth of the outer peripheral channel 123 is approximately 1 mm, similar to the depth D1 mentioned above.

[0044] A through-channel 124, which is a gas channel, is formed in the base member 120, extending from the outer peripheral channel 123 toward the fourth surface S4 and penetrating the base member 120 in its thickness direction. Although not shown in the figures, multiple through-channels 124 are formed at predetermined intervals in the circumferential direction along which the outer peripheral channel 123 extends, at the bottom of the outer peripheral channel 123. A fitting (not shown) is connected to the fourth surface S4 side of the through-channel 124, and a pipe (not shown) is connected to this fitting. An exhaust device or supply device (not shown) is connected to this pipe.

[0045] When an exhaust device is connected to this piping, the gas containing reactive gas that has accumulated inside the outer peripheral flow path 123 is drawn in by the exhaust device through the through-flow path 124 toward the fourth surface S4 and exhausted to the outside of the base member 120 via the joint and piping. As a result, the gas containing reactive gas is exhausted from inside the outer peripheral flow path 123, reducing the concentration of reactive gas near the bonding layer 130.

[0046] Furthermore, when an air supply device is connected to this piping, the air supply device can supply an inert gas such as helium to the inside of the outer peripheral flow path 123 through the through-flow path 124 via the piping and fittings. In this case, the reactive gas accumulating inside the outer peripheral flow path 123 is diluted by the inert gas. In addition, by supplying the inert gas to the inside of the outer peripheral flow path 123, the reactive gas accumulating inside the outer peripheral flow path 123 is exhausted by being pushed outwards towards the outer periphery of the base member 120. In this way, the accumulation of reactive gas in a high concentration in contact with the bonding layer 130 is suppressed.

[0047] Thus, even if the shapes of the outer peripheral portions of the plate-shaped member 110 and the base member 120 differ from those of the first embodiment, corrosion of the bonding layer 130 is suppressed by forming the outer peripheral channel 123 and the through channel 124 at a position on the outer peripheral side of the bonding layer arrangement portion 121 of the base member 120.

[0048] <Details of the third embodiment of this disclosure> Next, a holding device 200 according to the third embodiment of this disclosure will be described with reference to Figure 6. In the third embodiment, the same reference numerals are used for the same parts as in the first embodiment, and redundant explanations of the structure, operation, and effect will be omitted.

[0049] As shown in Figure 6, the holding device 200 comprises a plate-shaped member 10, a base member 220, and a bonding layer 230. The central planar portion of the third surface S3 of the base member 220 is the bonding layer arrangement portion 221 where the bonding layer 230 is placed. The portion of the base member 220 that is on the outer periphery of the bonding layer arrangement portion 221 is the outer periphery portion 222. An outer periphery flow path 223 is formed in the outer periphery portion 222. The outer periphery flow path 223 is a gas flow path formed in the shape of a groove that is recessed in an annular shape on the outer periphery portion 222, surrounding the bonding layer arrangement portion 221 when viewed in the Z-axis direction. The outer periphery flow path 223 is formed to a depth similar to the depth D1, similar to the outer periphery flow path 23 of the first embodiment.

[0050] A through-channel 224, which is a gas channel, is formed in the base member 220, extending from the outer peripheral channel 223 toward the fourth surface S4 and penetrating the base member 220 in its thickness direction. Although not shown in the figures, multiple through-channels 224 are formed at predetermined intervals in the circumferential direction in which the outer peripheral channel 223 extends, at the bottom of the outer peripheral channel 223. A fitting (not shown) is connected to the fourth surface S4 side of the through-channel 224, and piping (not shown) is connected to the fitting.

[0051] When the base member 20 according to the first embodiment and the base member 220 according to the third embodiment are the same size when viewed in the Z-axis direction, the bonding layer arrangement portion 221 is narrower than the bonding layer arrangement portion 21. That is, the outer peripheral end face of the bonding layer 230 according to the third embodiment is positioned further inward in the holding device 200 than the outer peripheral end face of the bonding layer 30 according to the first embodiment. In this way, by positioning the outer peripheral end face of the bonding layer 230 further away from the outer peripheral flow path 223 and inside the holding device 200, contact between the reactive gas and the bonding layer 230 when reactive gas accumulates in the outer peripheral flow path 223 is further suppressed. Furthermore, when an exhaust device (not shown) is connected to the through-flow path 224 via a joint and piping, gas containing the reactive gas is exhausted from inside the outer peripheral flow path 223. In this case as well, by positioning the outer peripheral end face of the bonding layer 230 away from the outer peripheral flow channel 223 and inside the holding device 200, even if reactive gas flows from outside the base member 220 toward the outer peripheral flow channel 223, contact with the bonding layer 230 is suppressed. Therefore, corrosion of the bonding layer 230 is suppressed.

[0052] In the holding device 200, the outer peripheral end face of the bonding layer 230 is positioned away from the outer peripheral flow channel 223 and towards the inside of the holding device 200, thereby forming a space SP surrounded by the outer peripheral end face of the bonding layer 230, the second surface S2 of the plate-shaped member 10, and the third surface S3 of the base member 220. This space SP may be filled with a plasma-resistant paste-like material. Alternatively, a sealing member such as an O-ring made of a plasma-resistant material may be placed in this space SP. In these cases, corrosion of the bonding layer 130 is further suppressed.

[0053] <Details of the fourth embodiment of this disclosure> Next, a holding device 300 according to the fourth embodiment of this disclosure will be described with reference to Figure 7. In the fourth embodiment, the same reference numerals are used for the same parts as in the first embodiment, and redundant explanations of the structure, operation, and effect will be omitted.

[0054] As shown in Figure 7, the holding device 300 comprises a plate-shaped member 10, a base member 320, and a bonding layer 30. The central flat portion of the third surface S3 of the base member 320 is designated as the bonding layer arrangement portion 321 where the bonding layer 30 is located. The portion of the base member 320 that is on the outer periphery of the bonding layer arrangement portion 321 is designated as the outer periphery portion 322. An outer periphery flow path 323 is formed in the outer periphery portion 322. The outer periphery flow path 323 is a gas flow path formed as a groove that is recessed in an annular shape on the outer periphery portion 322, surrounding the bonding layer arrangement portion 321 when viewed in the Z-axis direction.

[0055] As shown in Figure 7, the outer peripheral channel 323 is formed in a trapezoidal shape with a lower base shorter than the upper base in an XZ plan cross-sectional view. The depth of the outer peripheral channel 323 is approximately 1 mm, similar to the depth D1 mentioned above. At the bottom of the outer peripheral channel 323, which corresponds to the lower base of the trapezoid, a through channel 324 is formed with a diameter approximately the same as the length of the bottom, extending from the outer peripheral channel 323 toward the fourth surface S4 and penetrating the base member 320 in its thickness direction. In other words, the inner region of the outer peripheral channel 323 is formed to narrow from the upper part of the outer peripheral channel 323 toward the lower part where it connects to the through channel 324. Although not shown, multiple through channels 324 are formed at predetermined intervals in the circumferential direction along which the outer peripheral channel 323 extends, at the bottom of the outer peripheral channel 323. A joint (not shown) is connected to the fourth surface S4 side of the through channel 324, and piping (not shown) is connected to this joint. An exhaust device or air supply device (not shown) is connected to this piping.

[0056] Because the outer peripheral channel 323 is shaped in this way, when an exhaust device is connected to the piping, the gas containing reactive gas that remains inside the outer peripheral channel 323 flows easily into the through-channel 324 and is easily exhausted to the outside of the base member 320 via the joints and piping. When an air supply device is connected to the piping, the inert gas that has passed through the through-channel 324 via the piping and joints fills the inside of the outer peripheral channel 323 by spreading upward from the bottom of the outer peripheral channel 323, and the reactive gas that remains inside the outer peripheral channel 323 can be efficiently diluted. Furthermore, by supplying inert gas to the inside of the outer peripheral channel 323, the gas containing reactive gas does not remain inside the outer peripheral channel 323 and is easily exhausted by being pushed outwards towards the outer periphery of the base member 320.

[0057] Thus, by designing the shape of the outer peripheral channel 323, the contact of the reactive gas with the bonding layer 30 while its concentration remains high may be further suppressed. The shape of the outer peripheral channel 323 is not limited to this example; for example, it may have a rounded bottom in an XZ plan view. Alternatively, for example, in an XZ plan view, it may have a dovetail groove shape that widens from top to bottom, in the opposite direction to the outer peripheral channel 323.

[0058] <Details of the fifth embodiment of this disclosure> Next, a holding device 400 according to the fifth embodiment of this disclosure will be described with reference to Figure 8. In the fifth embodiment, the same reference numerals are used for the same parts as in the first embodiment, and redundant explanations of the structure, operation, and effect are omitted.

[0059] As shown in Figure 8, the holding device 400 comprises a plate-shaped member 410, a base member 420, and a bonding layer 430. The plate-shaped member 410 comprises a central portion 410A and a flange portion 410B. The central portion 410A and the flange portion 410B correspond to the central portion 10A and the flange portion 10B of the first embodiment, respectively. The flange portion 410B is configured to extend outwards from the outer circumference of the central portion 410A, and the width of the flange portion 410B in a view along the Z-axis is wider than that of the flange portion 10B extending outwards from the outer circumference of the central portion 10A.

[0060] The base member 420 comprises a bonding layer arrangement portion 421 and an outer peripheral portion 422. The bonding layer arrangement portion 421 constitutes the central part of the base member 420. The bonding layer 430 is arranged on the upper side of the bonding layer arrangement portion 421. The outer peripheral portion 422 extends substantially horizontally below the flange portion 410B of the plate-shaped member 410. The plate-shaped member 410 and the base member 420 are joined to each other by the bonding layer 430.

[0061] An outer peripheral channel 423 and a through-channel 424 are formed in the outer peripheral portion 422. The outer peripheral channel 423 and the through-channel 424 correspond to the outer peripheral channel 23 and the through-channel 24 of the first embodiment, respectively. A fitting (not shown) is connected to the fourth surface S4 side of the through-channel 424, and piping (not shown) is connected to the fitting. An exhaust device or an air supply device (not shown) is connected to this piping.

[0062] In the fifth embodiment, an outer peripheral channel 427 is further formed on the outer peripheral portion 422 at a position further outward than the outer peripheral channel 423. The outer peripheral channel 427 is formed as a groove that is recessed in an annular shape on the outer peripheral portion 422, surrounding the outer peripheral channel 423 and the through channel 424. The outer peripheral channel 427 is formed as a rectangular recess in an XZ plan cross-sectional view from the outer peripheral portion 422 toward the fourth surface S4. The depth of the outer peripheral channel 427 is the same as that of the outer peripheral channel 423. The depth of the outer peripheral channel 427 may be shallower or deeper than that of the outer peripheral channel 423.

[0063] A through-channel 428, which is a gas channel, is formed in the base member 420, extending from the outer peripheral channel 427 toward the fourth surface S4 and penetrating the base member 420 in its thickness direction. Although not shown in the figures, multiple through-channels 428 are formed at predetermined intervals in the circumferential direction along which the outer peripheral channel 427 extends, at the bottom of the outer peripheral channel 427. The through-channels 428 do not communicate with the through-channels 424 and are formed on the outer peripheral portion 422 at a position further outward than the through-channels 424. A fitting (not shown) is connected to the fourth surface S4 side of the through-channel 428, and piping (not shown) is connected to this fitting. An exhaust device or supply device (not shown) is connected to this piping.

[0064] When exhaust devices are connected to each of the through-flow channels 424 and 428 via joints and piping, the gas containing reactive gas that has accumulated inside each of the outer peripheral flow channels 423 and 427 is discharged to the fourth surface S4 side of the base member 420 through each of the through-flow channels 424 and 428. In this way, by including the outer peripheral flow channel 427 and through-flow channel 428 in addition to the outer peripheral flow channel 423 and through-flow channel 424, the contact of reactive gas with the bonding layer 430 at a high concentration is further suppressed.

[0065] Furthermore, when an air supply device is connected to each of the through-flow channels 424 and 428 via joints and piping, the gas containing reactive gases that has accumulated inside each of the outer peripheral flow channels 423 and 427 is diluted by the inert gas supplied through each of the through-flow channels 424 and 428. In addition, by supplying inert gas to each of the outer peripheral flow channels 423 and 427, the gas containing reactive gases inside each of the outer peripheral flow channels 423 and 427 is easily exhausted by being pushed outwards towards the outer periphery of the base member 420. In this way, by including the outer peripheral flow channels 427 and through-flow channels 428 in addition to the outer peripheral flow channels 423 and through-flow channels 424, the contact of reactive gases with the bonding layer 430 at a high concentration is further suppressed.

[0066] Furthermore, an air supply device may be connected to the through-channel 424 via joints and piping, and an exhaust device may be connected to the through-channel 428. In this case, the concentration of reactive gas inside the outer peripheral channel 423 is reduced, and the gas containing reactive gas inside the outer peripheral channel 423 is discharged, while the gas accumulated inside the outer peripheral channel 423 is exhausted toward the fourth surface S4, thereby suppressing exposure of the bonding layer 430 to reactive gas. Similarly, by connecting an exhaust device to the through-channel 424 via joints and piping, and an air supply device to the through-channel 428, exposure of the bonding layer 430 to reactive gas is also suppressed.

[0067] As described above, the base member 420 has another through-channel 428 located on the outer circumference of the through-channel 424, which does not communicate with the through-channel 424.

[0068] In this case, exhaust or inert gas supply is also performed in another through-flow channel 428, further suppressing the accumulation of reactive gas in contact with the bonding layer 430 at a high concentration.

[0069] <Details of the sixth embodiment of this disclosure> Next, a holding device 500 according to the sixth embodiment of this disclosure will be described with reference to Figures 9 to 11. In the sixth embodiment, the same reference numerals are used for the same parts as in the first embodiment, and redundant explanations of the structure, operation, and effect are omitted.

[0070] As shown in Figure 9, the holding device 500 comprises a plate-shaped member 10, a base member 520, and a bonding layer 530. The base member 520 is a substantially disc-shaped member having the same diameter as the plate-shaped member 10. The base member 520 has a third surface S3 located on the side of the plate-shaped member 10 and a fourth surface S4 located on the opposite side from the third surface S3.

[0071] The central flat portion of the third surface S3 of the base member 520 is designated as a bonding layer arrangement portion 521 where the bonding layer 530 is placed. Figure 10 shows the state in which the bonding layer 530 is placed over the entire bonding layer arrangement portion 521. When the bonding layer 530 is composed of an adhesive made of an organic resin material, the thickness T2 of the bonding layer 530 shown in Figure 9 is the same as the thickness T1 of the bonding layer 30 in the first embodiment, and is approximately 10 μm to 800 μm.

[0072] Furthermore, the portion of the base member 520 that is on the outer periphery of the joining layer arrangement portion 521 is designated as the outer periphery portion 522. The outer periphery portion 522 is positioned below the flange portion 10B of the plate-shaped member 10. As shown in Figure 10, with a portion of the joining layer 530 omitted, in the sixth embodiment, a groove portion corresponding to the outer periphery flow channel 23 in the first embodiment is not formed around the joining layer arrangement portion 521, and the portion of the outer periphery portion 522 that is continuous with the joining layer arrangement portion 521 extends horizontally at approximately the same height as the joining layer arrangement portion 21.

[0073] In this outer peripheral portion 522, through-channels 524, which are gas passages, are formed, extending from the third surface S3 to the fourth surface S4 and penetrating the base member 520 in its thickness direction. As shown in Figure 10, multiple through-channels 524 are formed at predetermined intervals, surrounding the bonding layer arrangement portion 521.

[0074] At a position on the outer circumference of the base member 520 where the through-channel 524 is formed, an outer peripheral projection 525 is formed, projecting from the third surface S3 toward the second surface S2 of the plate-like member 10, surrounding the through-channel 524 and the bonding layer arrangement portion 521. As shown in Figure 10, the outer peripheral projection 525 is an annular projection in the Z-axis direction, formed on the outer peripheral end of the base member 520. In the sixth embodiment, as shown in Figures 9 and 11, the outer peripheral projection 525 is formed to rise from the outermost position of the outer peripheral portion 522 toward the second surface S2. The outer peripheral projection 525 only needs to be located on the outer circumference of the through-channel 524; for example, it may be located slightly closer to the through-channel 524 than the outer peripheral end of the outer peripheral portion 522.

[0075] The height at which the outer peripheral projection 525 protrudes from the third surface S3 is such that the gap G1 between the upper end of the outer peripheral projection 525 and the second surface S2 of the plate-like member 10 is 0 or as narrow as possible. Preferably, the gap G1 is 0 μm to 30 μm. More preferably, the gap G1 is 0 μm to 5 μm. By providing such an outer peripheral projection 525, even when the holding device 500 is placed in a reactive gas atmosphere, the outer peripheral projection 525 prevents reactive gas from outside the holding device 500 from entering the inside of the holding device 500. As a result, the bonding layer 530 is less likely to be exposed to reactive gas, and corrosion of the bonding layer 530 is suppressed.

[0076] A fitting (not shown) is connected to the fourth surface S4 side of the through-flow channel 524, and piping (not shown) is connected to this fitting. An exhaust device or air supply device (not shown) is connected to this piping. If reactive gas enters the inside of the retaining device 500 through the gap G1, the invading reactive gas may accumulate in the region enclosed by the inner surface of the outer peripheral protrusion 525, the second surface S2, the third surface S3, and the outer peripheral end face of the bonding layer 530. If an exhaust device is connected to the piping, the gas containing the reactive gas accumulated in the above region is drawn in by the exhaust device towards the fourth surface S4 through the through-flow channel 524 and exhausted to the outside of the base member 520 via the fitting and piping. This reduces the concentration of reactive gas near the bonding layer 530.

[0077] Furthermore, when an air supply device is connected to the above-mentioned piping, the air supply device can supply an inert gas such as helium to the above-mentioned area through the through-flow channel 524 via the piping and fittings. In this case, the reactive gas accumulating near the joint layer 530 is diluted by the inert gas. In addition, by supplying the inert gas near the joint layer 530, the gas containing the reactive gas accumulating near the joint layer 530 is exhausted by being pushed out from the gap G1 toward the outside of the holding device 500 toward the outer circumference of the base member 520. In this way, the accumulation of reactive gas in contact with the joint layer 530 at a high concentration is suppressed, thereby suppressing corrosion of the joint layer 530.

[0078] As described above, the holding device 500 comprises a plate-shaped member 10 having a first surface S1 and a second surface S2 located on the opposite side of the first surface S1; a base member 520 having a third surface S3 positioned opposite to the second surface S2 and a fourth surface S4 located on the opposite side of the third surface S3; and a bonding layer 530 positioned between the second surface S2 and the third surface S3 to join the second surface S2 and the third surface S3. The base member 520 includes a bonding layer arrangement portion 521 on which the bonding layer 530 is disposed, a through-flow channel 524 which is a gas flow path provided on the outer periphery of the bonding layer arrangement portion 521 and extending from the third surface S3 to the fourth surface S4 and penetrating the base member 520 in the thickness direction, and an outer peripheral projection 525 which is located on the outer periphery of the through-flow channel 524 and protrudes from the third surface S3 to the second surface S2 so as to surround the through-flow channel 524 and the bonding layer arrangement portion 521.

[0079] When the inside of the processing chamber is subjected to a reactive gas atmosphere, the holding device 500 has an outer peripheral protrusion 525, which can block reactive gas from flowing from outside the holding device 500 toward the bonding layer 530. Furthermore, since the holding device 500 has a through-channel 524 located on the outer peripheral side of the base member 520 than the bonding layer arrangement portion 521, the reactive gas accumulated between the outer peripheral protrusion 525 and the bonding layer arrangement portion 521 can be exhausted toward the fourth surface S4 via the through-channel 524. In addition, by supplying inert gas from the through-channel 524, the holding device 500 can reduce the concentration of reactive gas accumulated between the outer peripheral protrusion 525 and the bonding layer arrangement portion 521, and can also exhaust the reactive gas accumulated between the outer peripheral protrusion 525 and the bonding layer arrangement portion 521 by pushing it outwards toward the outside of the holding device 500 through the gap G1 between the outer peripheral protrusion 525 and the second surface S2. In this way, the holding device 500 can prevent the reactive gas from remaining in contact with the bonding layer 530 at a high concentration. Therefore, the holding device 500 can suppress corrosion of the bonding layer 530.

[0080] <Details of the seventh embodiment of this disclosure> Next, a holding device 600 according to the seventh embodiment of this disclosure will be described with reference to Figures 12 and 13. In the seventh embodiment, the same reference numerals are used for the same parts as in the first embodiment, and redundant explanations of the structure, operation, and effect are omitted.

[0081] As shown in Figure 12, the holding device 600 comprises a plate-shaped member 10, a base member 620, and a bonding layer 630. The base member 620 is a substantially disc-shaped member having the same diameter as the plate-shaped member 10. The base member 620 has a third surface S3 located on the side facing the plate-shaped member 10, and a fourth surface S4 located on the opposite side from the third surface S3. A bonding layer arrangement portion 621, corresponding to the bonding layer arrangement portion 521 of the fifth embodiment, is provided in the central flat portion of the third surface S3 of the base member 620. The bonding layer 630 is arranged on the upper side of the bonding layer arrangement portion 621. When the bonding layer 530 is composed of an adhesive made of an organic resin material, the thickness T3 of the bonding layer 630 shown in Figure 12 is the same as the thickness T1 of the bonding layer 30 of the first embodiment, and is approximately 10 μm to 800 μm.

[0082] As shown in Figures 12 and 13, an outer peripheral projection 625, corresponding to the outer peripheral projection 525 of the fifth embodiment, is formed on the outer peripheral end of the base member 620. The gap G2 between the upper end of the outer peripheral projection 625 and the second surface S2 of the plate-shaped member 10 is preferably 0 μm to 30 μm, similar to the gap G1 of the fifth embodiment. Even when the holding device 600 is placed in a reactive gas atmosphere, the outer peripheral projection 525 prevents reactive gas from outside the holding device 600 from entering the inside of the holding device 600. As a result, the bonding layer 630 is less likely to be exposed to reactive gas, and corrosion of the bonding layer 630 is suppressed.

[0083] Furthermore, in the sixth embodiment, an outer peripheral channel 623 is formed between the outer peripheral protrusion 625 and the bonding layer arrangement portion 621 of the base member 620. The outer peripheral channel 623 corresponds to the outer peripheral channel 23 in the first embodiment and is formed as a gas channel that is recessed in an annular shape so as to surround the bonding layer arrangement portion 621. As shown in Figure 12, the depth D2 of the outer peripheral channel 623, that is, the length from the third surface S3 to the bottom of the outer peripheral channel 623, is about 1 mm, similar to the depth D1 of the outer peripheral channel 23 in the first embodiment.

[0084] The outer peripheral channel 623 is formed in the base member 620 at a position on the outer periphery of the bonding layer arrangement portion 621. Therefore, the base member 620 can prevent reactive gas that enters the inside of the holding device 600 from the gap G2 from coming into contact with the bonding layer 630 by allowing it to accumulate inside the outer peripheral channel 623.

[0085] Furthermore, in the sixth embodiment, multiple through-channels 624, corresponding to the through-channel 524 of the fifth embodiment, are formed so as to surround the joint layer arrangement portion 621. As shown in Figures 12 and 13, the through-channels 624 are formed at the bottom of the outer peripheral channel 623, extending from the outer peripheral channel 623 toward the fourth surface S4. A joint (not shown) is connected to the fourth surface S4 side of the through-channel 624, and piping (not shown) is connected to the joint. An exhaust device or air supply device (not shown) is connected to this piping.

[0086] When an exhaust device is connected to the piping, the gas containing reactive gas that has accumulated inside the outer peripheral flow path 623 is drawn in by the exhaust device through the through-flow path 624 toward the fourth surface S4 and exhausted to the outside of the base member 620 via the joint and piping. This reduces the concentration of reactive gas near the bonding layer 630.

[0087] Furthermore, when an air supply device is connected to the above piping, the air supply device can supply inert gas to the inside of the outer peripheral flow path 623 via the piping and fittings through the through-flow path 624. In this case, the reactive gas accumulating inside the outer peripheral flow path 623 and near the bonding layer 630 is diluted by the inert gas. In addition, by supplying inert gas to the inside of the outer peripheral flow path 623, the gas containing the reactive gas accumulating inside the outer peripheral flow path 623 and near the bonding layer 630 is exhausted by being pushed out from the gap G2 toward the outside of the holding device 600 towards the outer peripheral side of the base member 620. In this way, the accumulation of reactive gas in a high concentration in contact with the bonding layer 630 is suppressed, thereby suppressing corrosion of the bonding layer 630.

[0088] As described above, the base member 620 has an outer peripheral channel 623 formed in a groove shape between the outer peripheral protrusion 625 and the bonding layer arrangement portion 621, which is a gas flow path that surrounds the bonding layer arrangement portion 621. The through channel 624 is formed extending from the outer peripheral channel 623 toward the fourth surface S4.

[0089] In this case, the holding device 600 forms an outer peripheral channel 623 between the outer peripheral protrusion 625 and the bonding layer arrangement portion 621, so that reactive gas that enters between the outer peripheral protrusion 625 and the bonding layer arrangement portion 621 can be retained in the outer peripheral channel 623. Since a through channel 624 extends from this outer peripheral channel 623 toward the fourth surface S4, the holding device 600 can exhaust the gas containing the reactive gas retained in the outer peripheral channel 623 from the outer peripheral channel 623 toward the fourth surface S4 via the through channel 624. Furthermore, by supplying inert gas from the through channel 624, the holding device 600 can reduce the concentration of reactive gas retained in the outer peripheral channel 623 and exhaust the reactive gas retained in the outer peripheral channel 623 toward the outer peripheral side toward the outside of the outer peripheral channel 623. Therefore, the holding device 600 can further suppress corrosion of the bonding layer 630.

[0090] <Details of the eighth embodiment of this disclosure> Next, a holding device 700 according to the eighth embodiment of this disclosure will be described with reference to Figure 14. In the eighth embodiment, the same reference numerals are used for the same parts as in the first and fifth embodiments, and redundant explanations of the structure, operation, and effect are omitted.

[0091] As shown in Figure 14, the holding device 700 comprises a plate-shaped member 410, a base member 720, and a bonding layer 730. The base member 720 has a bonding layer placement section 721 in its central part. The bonding layer 730 is placed on the upper side of the bonding layer placement section 721.

[0092] In the base member 720, an annular recessed outer channel 723 is formed surrounding the bonding layer arrangement portion 721. In addition, a through channel 724, corresponding to the through channel 624 of the sixth embodiment, is formed extending from the outer channel 723 toward the fourth surface S4. Although not shown in the figures, multiple through channels 724 are formed at predetermined intervals in the circumferential direction in which the outer channel 723 extends, at the bottom of the outer channel 723.

[0093] Furthermore, an outer peripheral projection 725 is formed at a position on the outer peripheral side of the base member 720, relative to the outer peripheral channel 723. The outer peripheral projection 725 corresponds to the outer peripheral projection 525 of the fifth embodiment and is a projection that protrudes from the third surface S3 toward the second surface S2 of the plate-like member 10. In other words, the outer peripheral projection 725 is provided so as to surround the bonding layer arrangement portion 721, the outer peripheral channel 723, and the through channel 724, and protrudes from the third surface S3 of the base member 720 toward the second surface S2 of the plate-like member 410. Although not shown in the figures, the outer peripheral projection 725 protrudes in an annular shape on the third surface S3 in a view along the Z axis, surrounding the bonding layer arrangement portion 721, the outer peripheral channel 723, and the through channel 724.

[0094] In the base member 720, an outer peripheral channel 727 is further formed at a position further outward than the outer peripheral channel 723. The outer peripheral channel 727 is formed as a groove that is annularly recessed in a view along the Z axis, surrounding the outer peripheral channel 723 and the through channel 724. In addition, a through channel 728 is formed in the base member 720, extending from the outer peripheral channel 727 toward the fourth surface S4 and penetrating the base member 720 in its thickness direction. Although not shown in the figures, multiple through channels 728 are formed at predetermined intervals in the circumferential direction in which the outer peripheral channel 727 extends, at the bottom of the outer peripheral channel 727. The through channels 728 do not communicate with the through channel 724 and are formed at a position further outward than the through channel 724 in the outer peripheral portion 722. Furthermore, an outer peripheral protrusion 729 is formed so as to surround the outer peripheral channel 727 and the through channel 728. The outer peripheral projection 729, like the outer peripheral projection 725, protrudes in an annular shape on the third surface S3 when viewed in the Z-axis direction. In this way, since two projections, the outer peripheral projections 725 and 729, are provided between the outer peripheral end of the base member 720 and the bonding layer arrangement portion 721, the reactive gas directed from outside the holding device 700 to the bonding layer 730 is effectively prevented.

[0095] A fitting (not shown) is connected to the fourth surface S4 side of the through-flow channels 724 and 728, and a pipe (not shown) is connected to this fitting. An exhaust device or an air supply device (not shown) is connected to this pipe.

[0096] When exhaust devices are connected to each of the through-flow channels 724 and 728 via joints and piping, the gas containing reactive gas that has accumulated inside each of the outer peripheral flow channels 723 and 727 is discharged to the fourth surface S4 side of the base member 720 through each of the through-flow channels 724 and 728. In this way, because the base member 720 forms outer peripheral flow channels 727 and through-flow channels 728 in addition to outer peripheral flow channels 723 and through-flow channel 724, the contact of reactive gas with the bonding layer 730 at a high concentration is further suppressed.

[0097] Furthermore, when an air supply device is connected to each of the through-flow channels 724 and 728 via joints and piping, the gas containing reactive gases that has accumulated inside each of the outer perimeter flow channels 723 and 727 is diluted by the inert gas supplied through each of the through-flow channels 724 and 728. In addition, by supplying inert gas to each of the outer perimeter flow channels 723 and 727, the gas containing reactive gases inside each of the outer perimeter flow channels 723 and 727 is easily exhausted by being pushed outwards towards the outer perimeter of the base member 720. In this way, by including the outer perimeter flow channels 727 and through-flow channels 728 in addition to the outer perimeter flow channel 723 and through-flow channel 724, the contact of reactive gases with the bonding layer 730 at a high concentration is further suppressed.

[0098] In the eighth embodiment, an example was shown in which the base member 720 is formed such that the outer peripheral protrusions 725, 729, outer peripheral channels 723, 727, and through channels 724, 728 surround the joint layer arrangement portion 721. On the other hand, the base member 720 may be formed such that at least the outer peripheral protrusions 725, 729 and through channels 724, 728 surround the joint layer arrangement portion 721, and the outer peripheral channels 723, 727 are not formed. Even in this case, air is supplied or exhausted through the through channels 724, 728 to the region surrounded by the inner surfaces of the outer peripheral protrusions 725, 729 and the second surface S2 and the third surface S3, thereby reducing the concentration of reactive gases accumulating in these regions and suppressing corrosion of the joint layer 730.

[0099] As explained above, the base member 720 has another through-channel 728 located on the outer circumference of the through-channel 724, which does not communicate with the through-channel 724.

[0100] In this case, exhaust or inert gas supply is also performed in another through-flow channel 728, further suppressing the accumulation of reactive gas in contact with the bonding layer 730 at a high concentration.

[0101] <Other Embodiments> This disclosure is not limited to the embodiments described above and in the drawings. For example, the following embodiments are also included in the technical scope of this disclosure, and furthermore, various modifications can be made without departing from the spirit of the disclosure.

[0102] (1) The second surface S2 of the plate-shaped members 10, 110, 410, 510 and the third surface S3 of the base members 20, 120, 220, 320, 420, 520, 620, 720 are joined by brazing or soldering, and the joining layer 30, 130, 230, 530, 630, 730 may be composed of a layer of metal made of brazing material or solder. Such a joining layer 30, 130, 230, 530, 630, 730 may be formed of a metal such as aluminum or indium. When the joining layer 30, 130, 230, 530, 630, 730 is formed of a metal such as aluminum or indium, its thickness is, for example, about 10 μm to 300 μm.

[0103] (2) The second surface S2 of the plate-shaped members 10, 110, 410, 510 and the third surface S3 of the base members 20, 120, 220, 320, 420, 520, 620, 720 may be joined by screw fastening. In this case, a portion of the screw shaft is positioned between the second surface S2 of the plate-shaped members 10, 110, 410, 510 and the third surface S3 of the base members 20, 120, 220, 320, 420, 520, 620, 720. A portion of the screw positioned between the second surface S2 and the third surface S3 corresponds to the joining layers 30, 130, 230, 530, 630, 730. When the second surface S2 of the plate-shaped members 10, 110, 410, 510 and the third surface S3 of the base members 20, 120, 220, 320, 420, 520, 620, 720 are joined by screw fastening, it is preferable that a through hole is formed in the thickness direction of either the plate-shaped members 10, 110, 410, 510 or the base members 20, 120, 220, 320, 420, 520, 620, 720, and that a screw hole is formed in the other of the plate-shaped members 10, 110, 410, 510 or the base members 20, 120, 220, 320, 420, 520, 620, 720, and that a screw is fastened into that screw hole. In this case, a sealing member such as an O-ring may be provided around the through hole to suppress the intrusion of reactive gas into the through hole and the screw hole.

[0104] (3) The through-channels 24, 124, 224, 324, 424, 524, 624, and 724 may be provided one at a time around the joint layer arrangement section 21, 121, 221, 321, 421, 521, 621, and 721, or multiple through-channels may be provided. If multiple through-channels 24, 124, 224, 324, 424, 524, 624, and 724 are provided around the joint layer arrangement section 21, 121, 221, 321, 421, 521, 621, and 721, they may be provided at equal intervals or randomly.

[0105] (4) When multiple through-flow channels 24, 124, 224, 324, 424, 524, 624, 724 are provided around the joint layer arrangement section 21, 121, 221, 321, 421, 521, 621, 721, an exhaust device may be connected to one of the multiple through-flow channels 24, 124, 224, 324, 424, 524, 624, 724 via piping, and an air supply device may be connected to the remaining ones via piping.

[0106] (5) The first surface S1 of the plate-shaped members 10, 110, 410, and 510 may be provided with a plurality of protrusions for supporting the wafer W.

[0107] (6) The outer peripheral ends of the first surface S1 of the plate-shaped members 10, 110, 410, and 510 may be provided with annular protrusions for supporting the wafer W.

[0108] (7) Other electrodes besides the chuck electrode 40, such as heater electrodes, may be provided inside the plate-shaped members 10, 110, 410, and 510. Also, the plate-shaped members 10, 110, 410, and 510 do not need to contain electrodes such as the chuck electrode 40 inside them. [Explanation of Symbols]

[0109] 1,100,200,300,400,500,600,700: Holding device 10,110,410,510: Plate-shaped member 20,120,220,320,420,520,620,720: Base member 21,121,221,321,421,521,621,721: Joint layer arrangement section 24,124,224,324,424,524,624,724: Through-flow channel 23,123,223,323,423,427,623,723,727: Outer peripheral flow channel 30,130,230,430,530,630,730: Joint layer 525,625,725,729: Outer peripheral protrusion S1: 1st surface S2: 2nd surface S3: 3rd surface S4: 4th surface W: Wafer

Claims

1. A plate-shaped member having a first surface and a second surface located on the opposite side of the first surface, A base member having a third surface positioned opposite the second surface and a fourth surface located on the opposite side of the third surface, A bonding layer is disposed between the second surface and the third surface and joins the second surface and the third surface, The base member is The bonding layer arrangement portion where the bonding layer is arranged, An outer channel is a gas flow path provided at a position on the outer periphery of the aforementioned bonding layer arrangement portion, and is formed in a groove shape to surround the aforementioned bonding layer arrangement portion. A through-channel is a gas channel formed to extend from the outer peripheral channel toward the fourth surface and penetrate the base member in the thickness direction, A holding device equipped with the following features.

2. A plate-shaped member having a first surface and a second surface located on the opposite side of the first surface, A base member having a third surface positioned opposite the second surface and a fourth surface located on the opposite side of the third surface, A bonding layer is disposed between the second surface and the third surface and joins the second surface and the third surface, The base member is The bonding layer arrangement portion where the bonding layer is arranged, A through-channel is provided at a position on the outer periphery of the bonding layer arrangement portion, and is formed as a gas flow path that extends from the third surface to the fourth surface and penetrates the base member in the thickness direction, At a position on the outer circumference side of the through-flow channel, an outer peripheral projection is provided that surrounds the through-flow channel and the bonding layer arrangement portion, and protrudes from the third surface toward the second surface, A holding device equipped with the following features.

3. Between the outer peripheral protrusion and the bonding layer arrangement portion, an outer peripheral channel is formed, which is a gas flow path formed in a groove shape to surround the bonding layer arrangement portion. The holding device according to claim 2, wherein the through-flow channel is formed extending from the outer peripheral flow channel toward the fourth surface.

4. The holding device according to any one of claims 1 to 3, wherein another through-channel is formed at a position on the outer circumference side of the aforementioned through-channel, and does not communicate with the aforementioned through-channel.

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