JP7747580B2 - Semiconductor manufacturing equipment and holding equipment - Google Patents

Description

This disclosure relates to metal members, semiconductor manufacturing equipment, and holding devices.

One example of a holding device is the electrostatic chuck described in Patent Document 1 below. This electrostatic chuck includes a support body that has an electrode inside and supports a substrate, a cooling base that is coupled to the support body and controls the temperature of the support body, and a facility plate that is coupled to the cooling base. The electrostatic chuck is placed in a processing chamber for plasma processing of the substrate.

A groove for placing a seal (O-ring) is formed on the underside of the cooling base. The seal placed in this groove is compressed between the cooling base and the facility plate, preventing the passage of fluid between the cooling base and the facility plate. The seal is placed to surround the area connecting the electrostatic chuck to devices located outside the processing chamber (e.g., electrode power supplies, coolant supply devices, gas supply devices, etc.). This prevents outside air from entering the processing chamber.

Japanese Patent Application Laid-Open No. 2020-13993

In processing chambers like the one described above, it is known that the high-frequency power applied during plasma processing can cause unintended abnormal discharges (arcing) in the gas flow paths of the electrostatic chuck. When abnormal discharges occur, the processing quality of the substrate deteriorates, resulting in lower yields. To reduce the occurrence of abnormal discharges, the surface of the cooling base is typically insulated by anodizing or other methods.

However, in the past, the inner walls of the grooves in which the seals were placed were not anodized. This was because it was difficult to reduce the surface roughness of the inner walls of anodized grooves. If the surface roughness of the inner walls of the grooves was high, gaps would form between the seals and the inner walls of the grooves, making it impossible to ensure the sealing of the processing chamber. As a result, the metal was exposed on the inner walls of the grooves, and no measures were taken to prevent abnormal discharge.

This disclosure was developed based on the above circumstances, and aims to reduce the occurrence of abnormal discharge in semiconductor manufacturing equipment compared to conventional methods while ensuring sealing performance.

The metal member disclosed herein is a metal member that is bonded to another member via a sealing member, and includes an opposing surface that faces the other member, and a recess that is recessed from the opposing surface and has the sealing member disposed therein. The recess includes a bottom wall and a pair of side walls that connect both side edges of the bottom wall to the opposing surface. The opposing surface, the bottom wall, and the pair of side walls have a barrier layer, and the bottom wall has a silicone layer on the barrier layer of the bottom wall.

This disclosure makes it possible to reduce the occurrence of abnormal discharge in semiconductor manufacturing equipment compared to conventional methods while ensuring sealing performance.

FIG. 1 is a perspective view schematically illustrating the external configuration of an electrostatic chuck according to a first embodiment. FIG. 2 is a cross-sectional view schematically showing the connection between the electrostatic chuck and the chamber in the semiconductor manufacturing apparatus according to the first embodiment. FIG. 3 is an enlarged cross-sectional view schematically illustrating the periphery of the recess according to the first embodiment. FIG. 4 is an enlarged cross-sectional view schematically showing the periphery of a recess according to a comparative example. FIG. 5 is a cross-sectional view schematically showing the connection between the electrostatic chuck and the mounting plate in the semiconductor manufacturing apparatus according to the second embodiment. FIG. 6 is a cross-sectional view schematically showing the bonding between the metal member and the ceramic member in the electrostatic chuck according to the third embodiment.

Description of the embodiments of the present disclosure
First, embodiments of the present disclosure will be listed and described.
(1) The metal member of the present disclosure is a metal member that is joined to another member via a sealing member, and includes an opposing surface that faces the other member, and a recess that is recessed from the opposing surface and has the sealing member disposed therein. The recess includes a bottom wall portion and a pair of side wall portions that connect both side edges of the bottom wall portion to the opposing surface. The opposing surface, the bottom wall portion, and the pair of side wall portions have a barrier layer, and the bottom wall portion includes a silicone layer on the barrier layer of the bottom wall portion.

The recessed portion is provided with a barrier layer, which helps prevent arcing in the recessed portion when the metal component is used in semiconductor manufacturing equipment.

Because the barrier layer on the bottom wall of the recess is recessed from the opposing surface, it is difficult to perform polishing processes, resulting in a high level of surface roughness. When the bottom wall of the recess has a high level of surface roughness, compressing the sealing member between the bottom wall and another member can create a gap between the sealing member and the bottom wall, potentially resulting in an inability to seal the joint between the metal member and the other member. In such cases, atmospheric air leaks into the vacuum system of the semiconductor manufacturing equipment. However, with the above configuration, the bottom wall is provided with a silicone layer covering the barrier layer, allowing the silicone layer to adhere tightly to the sealing member. This prevents a gap from forming between the bottom wall and the sealing member, ensuring a seal between the joint between the metal member and the other member. This prevents atmospheric air leaks into the vacuum system of the semiconductor manufacturing equipment.

(2) The maximum surface height Rz of the silicone layer is preferably 60 μm or less.

The above configuration facilitates adhesion between the silicone layer and the sealing member, further ensuring the sealing performance of the sealing member. Note that the maximum height Rz (JIS B0601:2013) is one of the parameters that indicate surface roughness.

(3) The hardness of the silicone layer is preferably 10 or more and 60 or less in Shore A hardness.

The silicone layer has a hardness of 10 or more and 60 or less on the Shore A hardness scale, making it relatively softer than, for example, metal members or barrier layers, making it easy to adhere the silicone layer to the sealing member. Furthermore, when the sealing member is compressed between the bottom wall and another member, the reaction force from the sealing member acting on the bottom wall can be alleviated. Because the reaction force from the sealing member can be alleviated, the range of options for the hardness of the sealing member can be expanded.

(4) The thickness of the silicone layer is preferably 15 to 25% of the depth of the recess.

Increasing the thickness of the silicone layer makes it easier to reduce the surface roughness of the bottom wall, but it also increases the reaction force from the sealing member, making it difficult to bond the metal member to other members. With the above configuration, the sealing performance of the sealing member is ensured while reducing the reaction force from the sealing member, making it easier to bond the metal member to other members.

(5) The semiconductor manufacturing apparatus of the present disclosure may be a semiconductor manufacturing apparatus including the above-described metal member, a sealing member disposed in the recess, and a chamber including a chamber bottom wall to which the metal member is coupled via the sealing member.

(6) The semiconductor manufacturing apparatus disclosed herein may also include the above-described metal member, a sealing member disposed in the recess, and an installation plate to which the metal member is joined via the sealing member.

The above-mentioned semiconductor manufacturing equipment can suppress arcing and ensure the sealing performance of the sealing member.

(7) The holding device of the present disclosure may be a holding device including the above-mentioned metal member, a sealing member disposed in the recess, and a ceramic member to which the metal member is joined via the sealing member.

The above-mentioned holding device can suppress arcing and ensure the sealing performance of the sealing member.

[Details of the First Embodiment of the Present Disclosure]
A first embodiment of the present disclosure will be described with reference to Figures 1 to 4. Note that the present disclosure is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims. In the following description, when multiple identical components are used, only some of the components may be designated by reference numerals, and the reference numerals for other components may be omitted.

<Semiconductor manufacturing equipment>
The semiconductor manufacturing apparatus 70 of the first embodiment is for performing various processes (such as film formation and etching) on semiconductor wafers, glass substrates, or the like (hereinafter referred to as "wafers W") using plasma under reduced pressure. As shown in Fig. 2, the semiconductor manufacturing apparatus 70 includes a chamber 50, an electrostatic chuck 10 fixed within the chamber 50, and an external device 60 disposed outside the chamber 50. The external device 60 includes, for example, a vacuum pump 61, a gas supply device 62, a coolant circulation device 63, a power supply 64, and the like.

The chamber 50 defines a closed internal space 53, excluding the portion connecting to the external device 60. The chamber 50 includes a chamber bottom wall 51 (an example of another member) to which the metal member 30 of the electrostatic chuck 10 is coupled. The chamber bottom wall 51 is provided with a through-hole 52 for introducing piping, wiring, etc. connected to the external device 60 into the chamber 50. A sealing member S1, such as an O-ring or MSE seal, is disposed around the through-hole 52. The sealing member S1 is compressed between the metal member 30 and the chamber bottom wall 51, preventing outside air from entering through the through-hole 52. This allows the pressure inside the chamber 50 to be reduced by a vacuum pump 61. Note that the distance between the metal member 30 and the chamber bottom wall 51 is exaggerated in the drawings for clarity.

<Electrostatic chuck>
As shown in Fig. 1, the electrostatic chuck 10 includes a ceramic member 20 and a metal member 30. As shown in Fig. 2, the ceramic member 20 and the metal member 30 are bonded together by a bonding portion 26. The bonding portion 26 is formed of an adhesive such as a silicone-based resin, an acrylic-based resin, or an epoxy-based resin. The electrostatic chuck 10 is capable of attracting and holding the wafer W by electrostatic attraction.

<Ceramics components>
The ceramic member 20 has an overall disk shape and can be formed into a shape with, for example, a diameter of approximately 300 mm and a thickness of approximately 3 mm. As shown in FIG. 2 , the ceramic member 20 has a first surface 20A for holding the wafer W and a second surface 20B disposed on the opposite side of the first surface 20A. The first surface 20A is disposed on the upper side of the ceramic member 20, and the second surface 20B is disposed on the lower side of the ceramic member 20. The ceramic member 20 includes a ceramic insulator 21 and a chuck electrode 27 and a heater electrode (not shown) disposed inside the insulator 21. The chuck electrode 27 is disposed closer to the first surface 20A. The heater electrode is disposed below the chuck electrode 27. The chuck electrode 27 exerts an electrostatic chucking force when a voltage is applied. The heater electrode is configured to generate heat when a voltage is applied and a current flows through it.

The chuck electrode 27 and heater electrode are primarily composed of tungsten, molybdenum, alloys of these, or carbides of these. The chuck electrode and heater electrode may also be made of metallized material with a sintered conductive layer printed with conductive paste, metal foil, metal mesh, etc.

A terminal 24 (only one shown) is connected to each of the heater electrode and the chuck electrode 27. Each terminal 24 is arranged to penetrate the metal member 30 in the vertical direction. Each terminal 24 is connected to a power source 64 located outside the chamber 50 via wiring or the like.

<Insulator>
The insulator 21 is mainly composed of alumina, aluminum nitride, yttria, or a composite material of alumina and silicon carbide.

A gas flow path 22 is formed inside the insulator 21, through which an inert gas such as helium flows. An outlet 23 that communicates with the gas flow path 22 is formed on the surface of the insulator 21. The inert gas supplied to the gas flow path 22 from the gas supply device 62 is discharged from the outlet 23. This introduces the inert gas into the space between the wafer W and the ceramic member 20. Introducing the inert gas into this space can improve thermal conduction between the wafer W and the ceramic member 20.

<Metallic parts>
The metal member 30 is a substantially circular, flat, plate-like member having the same diameter as or a larger diameter than the ceramic member 20. For example, the metal member 30 can be formed into a shape having a diameter of approximately 340 mm and a thickness of approximately 20 mm. The metal member 30 is primarily composed of aluminum, an aluminum alloy, or the like. The metal member 30 has a third surface 30A disposed on the ceramic member 20 side and a fourth surface 30B disposed on the chamber bottom wall 51 side. The third surface 30A is disposed on the upper side of the metal member 30, and the fourth surface 30B is disposed on the lower side of the metal member 30. The third surface 30A is bonded to the second surface 20B of the ceramic member 20 by a bonding portion 26. The fourth surface 30B (an example of an opposing surface) faces the chamber bottom wall 51.

A refrigerant flow path 31 is provided inside the metal member 30. The refrigerant flow path 31 is connected to a refrigerant circulation device 63 via piping or the like. The refrigerant circulation device 63 is configured to circulate a refrigerant, such as a fluorine-based inert liquid or water, through the refrigerant flow path 31. When the refrigerant flows through the refrigerant flow path 31, the metal member 30 is cooled, and heat transfer (heat dissipation) between the metal member 30 and the ceramic member 20 via the joint 26 cools the ceramic member 20, thereby cooling the wafer W held by the first surface 20A of the ceramic member 20. This allows the temperature of the wafer W to be controlled.

The metal member 30 is provided with a terminal hole 32 that receives the terminal 24 and a gas inlet passage 33 that communicates with the gas flow path 22 of the ceramic member 20. The terminal hole 32 and the gas inlet passage 33 are formed to penetrate the metal member 30 in the vertical direction. The gas inlet passage 33 is connected to a gas supply device 62 located outside the chamber 50 via piping or the like.

The metal member 30 is connected to the chamber bottom wall 51 via a sealing member S1. Although not shown, the metal member 30 and the chamber bottom wall 51 can be connected, for example, by bolt fastening. A configuration can be employed in which insertion holes through which bolts are inserted are formed on the outer periphery of the metal member 30, and fastening portions into which the bolts are fastened are provided on the chamber bottom wall 51.

As shown in FIG. 3 , the metal member 30 has a groove-shaped recess 34 recessed from the fourth surface 30B. A sealing member S1 is disposed within the recess 34. The recess 34 includes a bottom wall 35 and a pair of side walls 36 connecting both side edges of the bottom wall 35 to the fourth surface 30B. The fourth surface 30B, the bottom wall 35, and the pair of side walls 36 have an anodized aluminum layer AL (an example of a barrier layer). This anodized aluminum layer AL is formed by anodizing the metal member 30. The anodized aluminum layer AL may also be provided on the third surface 30A or side surface of the metal member 30. Providing the anodized aluminum layer AL on the metal member 30 reduces the occurrence of abnormal discharge during plasma processing in the semiconductor manufacturing apparatus 70.

When the anodized aluminum layer AL is first formed by anodizing, it has a high surface roughness. The surface roughness of the anodized aluminum layer AL on the fourth surface 30B has been reduced by polishing. However, it is difficult to reduce the surface roughness of the anodized aluminum layer AL on the bottom wall portion 35 and the pair of side wall portions 36, which are located recessed from the fourth surface 30B, by polishing.

Now, referring to FIG. 4, consider a comparative example in which the bottom wall 35 and the pair of sidewalls 36 have high surface roughness, a seal member S1 is placed in the recess 34, and the metal member 30 is bonded to the chamber bottom wall 51. In this case, when the seal member S1 is compressed between the bottom wall 35 and the chamber bottom wall 51, a small gap is created between the seal member S1 and the anodized aluminum layer AL of the bottom wall 35. This gap is large enough to allow fluid to pass through, allowing outside air to enter the interior space 53 of the chamber 50 through the through-hole 52 in the chamber bottom wall 51 located inside the seal member S1. For example, in FIG. 4, arrows indicate the entry of outside air into the interior space 53 of the chamber 50 through the through-hole 52 through which the connection wiring 25 connecting the terminal 24 to the power source 64 outside the chamber 50 is introduced. Therefore, even if the gas in the interior space 53 of the chamber 50 is exhausted by the vacuum pump 61, the pressure inside the chamber 50 cannot be reduced (see FIG. 2). As a result, plasma cannot be generated in the semiconductor manufacturing equipment 70, and wafer W cannot be processed.

In contrast, in this embodiment, as shown in Figure 3, a silicone layer SL is formed on the outside of the anodized aluminum layer AL of the bottom wall portion 35. The silicone layer SL is formed by applying a curable silicone resin to the bottom wall portion 35 and then curing it. This eliminates the uneven shape of the anodized aluminum layer AL of the bottom wall portion 35.

In this embodiment, when the sealing member S1 disposed within the recess 34 is compressed between the bottom wall 35 and the chamber bottom wall 51, the sealing member S1 adheres to the silicone layer SL, thereby ensuring the sealing performance of the sealing member S1. For example, in FIG. 3, outside air that enters the terminal hole 32 from the through-hole 52 through which the connection wiring 25 connecting the terminal 24 to the power source 64 outside the chamber 50 is introduced cannot penetrate between the bottom wall 35 and the sealing member S1 and into the internal space 53 of the chamber 50 because the silicone layer SL and the sealing member S1 are in close contact. Therefore, the pressure inside the chamber 50 can be reduced by the vacuum pump 61, enabling processing of wafers W in the semiconductor manufacturing apparatus 70 (see FIG. 2).

<Metallic member manufacturing method>
An example of a method for manufacturing the metal member 30 of this embodiment will be described below.
First, a metal disk-shaped member that will form the metal member 30 is prepared. This disk-shaped member is machined to form the recess 34. An anodized aluminum layer AL is formed on the disk-shaped member with the recess 34. This results in the formation of an anodized aluminum layer AL on the outer surface of the disk-shaped member (e.g., the third surface 30A, side surfaces, etc.) and on the bottom wall 35 and pair of side wall portions 36 of the recess 34. Note that the manufacture of the metal member 30 may begin after preparing a disk-shaped member on which the manufacturing process up to this point (i.e., the formation of the recess 34 and the anodizing treatment) has been completed. Next, a silicone-based resin is applied to the anodized aluminum layer AL on the bottom wall portion 35 of the recess 34 and cured. This allows the silicone layer SL to be formed on the anodized aluminum layer AL on the bottom wall portion 35. This completes the manufacture of the metal member 30 of this embodiment.

<Effects of First Embodiment>
As described above, the metal member 30 of embodiment 1 is a metal member 30 that is joined to another member (chamber bottom wall 51) via the sealing member S1, and includes an opposing surface (fourth surface 30B) that faces the other member, and a recess 34 that is recessed from the opposing surface and has the sealing member S1 disposed therein. The recess 34 includes a bottom wall portion 35 and a pair of side wall portions 36 that connect both side edges of the bottom wall portion 35 to the opposing surface. The opposing surface, the bottom wall portion 35, and the pair of side wall portions 36 have a barrier layer (anodized layer AL), and the bottom wall portion 35 includes a silicone layer SL on the barrier layer of the bottom wall portion 35.

Because the recess 34 is provided with a barrier layer, arcing can be suppressed in the recess 34 when the metal component 30 is used in the semiconductor manufacturing equipment 70.

Because the barrier layer on the bottom wall 35 of the recess 34 is recessed from the opposing surface, it is difficult to perform polishing or other processes, resulting in high surface roughness. If the bottom wall 35 of the recess 34 has high surface roughness, compressing the seal member S1 between the bottom wall 35 and another component can create a gap between the seal member S1 and the bottom wall 35, potentially resulting in an inability to seal the joint between the metal component 30 and the other component. In such cases, atmospheric air leaks into the vacuum system of the semiconductor manufacturing equipment 70. However, with the above configuration, the bottom wall 35 includes a silicone layer SL covering the barrier layer, allowing the silicone layer SL to be tightly attached to the seal member S1. This prevents a gap from forming between the bottom wall 35 and the seal member S1, ensuring a seal between the joint between the metal component 30 and the other component. This prevents atmospheric air leaks into the vacuum system of the semiconductor manufacturing equipment 70.

In embodiment 1, the maximum height Rz of the surface of the silicone layer SL is preferably 60 μm or less.

With the above configuration, the surface of the silicone layer SL does not have large irregularities. This makes it easier for the silicone layer SL and the sealing member S1 to adhere to each other, further ensuring the sealing properties of the sealing member S1.

In embodiment 1, the hardness of the silicone layer SL is preferably 10 or more and 60 or less in Shore A hardness.

The silicone layer SL has a hardness of 10 or more and 60 or less on the Shore A hardness scale, making it relatively softer than, for example, the metal member 30 or the barrier layer, making it easy to adhere the silicone layer SL to the sealing member S1. Furthermore, when the sealing member S1 is compressed between the bottom wall portion 35 and another member, the reaction force from the sealing member S1 applied to the bottom wall portion 35 can be alleviated. Because the reaction force from the sealing member S1 can be alleviated, the range of options for the hardness of the sealing member S1 is expanded. The hardness of the silicone layer SL can be adjusted by adjusting the filler content in the uncured silicone-based resin that forms the silicone layer SL.

In embodiment 1, the thickness of the silicone layer SL is preferably 15 to 25% of the depth of the recess 34.

Increasing the thickness of the silicone layer SL makes it easier to reduce the surface roughness of the bottom wall portion 35, but increases the reaction force from the sealing member S1, making it difficult to bond the metal member 30 to other members. With the above configuration, the sealing performance of the sealing member S1 is ensured while reducing the reaction force from the sealing member S1, making it easier to bond the metal member 30 to other members.

The semiconductor manufacturing apparatus 70 of embodiment 1 includes the above-described metal member 30, a seal member S1 disposed within the recess 34, and a chamber 50 including a chamber bottom wall 51 to which the metal member 30 is coupled via the seal member S1.

The semiconductor manufacturing apparatus 70 of embodiment 1 can suppress arcing and ensure the sealing performance of the sealing member S1.

[Details of the Second Embodiment of the Present Disclosure]
A second embodiment of the present disclosure will be described with reference to FIG. 5 . A semiconductor manufacturing apparatus 170 of the second embodiment further includes a mounting plate 40 between a chamber bottom wall 51 and a metal member 30, and the metal member 30 is coupled to the mounting plate 40 (an example of another member). The other configurations of the second embodiment are similar to those of the first embodiment. Hereinafter, the same members as those of the first embodiment will be assigned the same reference numerals as those of the first embodiment, and a description of the same configurations, functions, and effects as those of the first embodiment will be omitted.

<Installation board>
The mounting plate 40 is made of metal and has a disk shape. The mounting plate 40 has a fifth surface 40A disposed on the metal member 30 side and a sixth surface 40B disposed on the chamber bottom wall 51 side. The fifth surface 40A is disposed on the upper side of the mounting plate 40, and the sixth surface 40B is disposed on the lower side of the mounting plate 40. Similar to the metal member 30, the mounting plate 40 has a terminal hole 42 and a gas introduction path 43 formed therein. The mounting plate 40 also has a coolant introduction path 41 that communicates with the coolant flow path 31.

The installation plate 40 has a recess 44 recessed from the sixth surface 40B. Although not shown in detail, the recess 44 is configured similarly to the recess 34 of the metal member 30. That is, although not shown, the recess 44 has a bottom wall and a pair of side walls, and the bottom wall, the pair of side walls, and the sixth surface 40A have an anodized aluminum layer AL (see Figure 3). The anodized aluminum layer AL on the bottom wall of the recess 44 is covered with a silicone layer SL. With a sealing member S2 disposed inside the recess 44, the installation plate 40 is joined to the chamber bottom wall 51 by bolting or the like.

In this embodiment, the sealing member S1 disposed within the recess 34 of the metal member 30 is compressed between the bottom wall portion 35 and the fifth surface 40A of the installation plate 40. Because the bottom wall portion 35 has a silicone layer SL, the silicone layer SL and the sealing member S1 come into close contact with each other, preventing fluid from passing between the bottom wall portion 35 and the sealing member S1. This ensures sealing performance by the sealing member S1. Similarly, the sealing member S2 disposed within the recess 44 of the installation plate 40 comes into close contact with the silicone layer SL on the bottom wall of the recess 44, ensuring sealing performance by the sealing member S2.

<Effects of the Second Embodiment>
The semiconductor manufacturing apparatus 170 of the second embodiment includes a metal member 30, a seal member S1 disposed in the recess 34, and a mounting plate 40 to which the metal member 30 is coupled via the seal member S1.

This semiconductor manufacturing equipment 170 can suppress arcing and ensure the sealing performance of the sealing member S1.

[Details of Embodiment 3 of the Present Disclosure]
A third embodiment of the present disclosure will be described with reference to FIG. 6 . In an electrostatic chuck 210 (an example of a holding device) of a semiconductor manufacturing apparatus 270 of the third embodiment, a ceramic member 220 and a metal member 230 are not joined by a joint, and the metal member 230 is coupled to the ceramic member 220 (an example of another member) via a seal member S3 by bolt fastening or the like. Specifically, an insertion hole 228 through which a bolt B1 is inserted is formed on the outer periphery of the ceramic member 220. A fastening portion 237 through which the bolt B1 is fastened is provided on the outer periphery of the metal member 230. The remaining configuration of the third embodiment is similar to that of the first embodiment. Hereinafter, the same components as those of the first embodiment will be designated by the same reference numerals as those used in the first embodiment, and a description of the same configurations, functions, and effects as those of the first embodiment will be omitted.

The metal member 230 has a third surface 230A (an example of an opposing surface) facing the ceramic member 220, and a fourth surface 30B disposed on the chamber bottom wall 51 side. The metal member 230 has a recess 234 recessed from the third surface 230A. The recess 234 is configured similarly to the recess 34 provided on the fourth surface 30B side. That is, although not shown, the recess 234 has a bottom wall and a pair of side walls, and the bottom wall, the pair of side walls, and the third surface 230A have an anodized aluminum layer AL (see Figure 3). The anodized aluminum layer AL on the bottom wall of the recess 234 is covered with a silicone layer SL.

In this embodiment, the sealing member S3 disposed within the recess 234 of the metal member 230 is compressed between the bottom wall of the recess 234 and the second surface 20B of the ceramic member 220. Because the bottom wall of the recess 234 has a silicone layer SL, the silicone layer SL and the sealing member S3 come into close contact with each other, preventing fluid from passing between the bottom wall of the recess 234 and the sealing member S3. This ensures the sealing performance of the sealing member S3.

<Effects of the Third Embodiment>
The holding device (electrostatic chuck 210) of embodiment 3 includes a metal member 230, a seal member S3 disposed in the recess 234, and a ceramic member 220 to which the metal member 230 is joined via the seal member S3.

This holding device suppresses arcing and ensures the sealing performance of the sealing member S3.

<Other Embodiments>
(1) In FIG. 3 of the first embodiment, the entire anodized aluminum layer AL of the bottom wall portion 35 is covered with the silicone layer SL. However, the silicone layer need only cover the anodized aluminum layer of the bottom wall portion to an extent that abnormal discharge can be suppressed, and a configuration in which only a portion of the anodized aluminum layer of the bottom wall portion is not covered by the silicone layer may also be adopted.

(2) In embodiment 1, the metal member 30 is coupled to the chamber bottom wall 51 via the sealing member S1, in embodiment 2 the metal member 30 is coupled to the installation plate 40 via the sealing member S1, and in embodiment 3 the metal member 230 is coupled to the ceramic member 220 via the sealing member S3, but the metal member may also be coupled to a member other than those described above via a sealing member.

(3) In embodiment 1, the cross-sectional shape of the recess 34 was rectangular, but the recess may also be dovetail-shaped.

10, 210...Electrostatic chuck (holding device)
DESCRIPTION OF SYMBOLS 20, 220...Ceramic member 20A...First surface 20B...Second surface 21...Insulator 22...Gas flow path 23...Outlet 24...Terminal 25...Connection wiring 26...Joint 27...Chuck electrode 228...Insertion hole 30, 230...Metal member 30A, 230A...Third surface 30B...Fourth surface 31...Coolant flow path 32...Terminal hole 33...Gas introduction path 34, 234...Recess 35...Bottom wall 36...Side wall 237...Fastening portion 40...Installation plate 40A...Fifth surface 40B...Sixth surface 41...Coolant introduction path 42...Terminal hole 43...Gas introduction path 44...Recess 50...Chamber 51...Chamber bottom wall 52...Through hole 53...Inner space 60...External device 61...Vacuum pump 62...Gas supply device 63...Refrigerant circulation device 64...Power supply 70, 170, 270...Semiconductor manufacturing device AL...Alumite layer (barrier layer) B1...Bolt S1, S2, S3...Sealing member SL...Silicone layer W...Wafer

Claims (7)

A holding device that adsorbs and holds a wafer by electrostatic attraction, the holding device comprising: a ceramic member; a metal member; and a joint portion disposed between the ceramic member and the metal member,
the metal member is connected to another member via a sealing member,
the metal member includes an opposing surface facing the other member, and a recess recessed from the opposing surface and having the seal member disposed therein;
the recess includes a bottom wall portion and a pair of side wall portions connecting both side edges of the bottom wall portion to the opposing surface,
the opposing surface, the bottom wall portion, and the pair of side wall portions have a barrier layer;
The bottom wall comprises a silicone layer on the barrier layer of the bottom wall. The holding device according to claim 1 , wherein the maximum height Rz of the surface of the silicone layer is 60 μm or less. The retaining device according to claim 1 , wherein the silicone layer has a hardness of 10 or more and 60 or less in Shore A hardness. The retaining device according to claim 1 , wherein the thickness of the silicone layer is 15 to 25% of the depth of the recess. A holding device according to any one of claims 1 to 4;
a sealing member disposed within the recess;
a chamber having a chamber bottom wall to which the metal member is joined via the seal member. A holding device according to any one of claims 1 to 4;
a sealing member disposed within the recess;
a mounting plate to which the metal member is joined via the sealing member. A holding device according to any one of claims 1 to 4,
a sealing member disposed within the recess;
a ceramic member to which the metal member is joined via the seal member.