Holding device

Abstract

The objective is to provide a technology that suppresses the occurrence of arcing and prevents leakage of the bonding material. [Solution] The gas flow path FPB includes a base material side gas flow path FPB1 formed inside the base material 210, a plate-shaped member side gas flow path FPB2 formed inside the plate-shaped member, a metal bonding layer side gas flow path FPB3 formed inside the metal bonding layer, and an annular member side gas flow path FPB4 formed inside the annular member and communicating with at least one of the base material side gas flow path and the plate-shaped member side gas flow path. The porous body 250 is arranged inside at least one of the base material side gas flow path FPB1 and the plate-shaped member side gas flow path FPB2, and the annular member 233 is arranged inside the metal bonding layer side gas flow path FPB3 when viewed from the upper surface 220a of the plate-shaped member 220, and covers at least a part of the porous body.

Description

Technical Field

[0001] The present disclosure relates to a holding device for holding an object.

Background Art

[0002] As a holding device for holding a wafer in a semiconductor processing apparatus, for example, an electrostatic chuck is used. An electrostatic chuck generally has a ceramic member having an adsorption surface and a base material. The ceramic member and the base material are bonded by an adhesive. A chuck electrode is provided inside the ceramic member. By utilizing the electrostatic attraction generated when a voltage is applied to the chuck electrode, the electrostatic chuck adsorbs and holds the wafer on the adsorption surface of the ceramic member.

[0003] Some semiconductor processing apparatuses have an electrostatic chuck with a large number of through-holes for processing a semiconductor wafer with plasma. In this semiconductor processing apparatus, an inert gas is supplied to the space where the back surface of the semiconductor wafer is exposed through the large number of through-holes in the electrostatic chuck. The inert gas can keep the in-plane temperature distribution of the semiconductor wafer substantially uniform.

[0004] Patent Document 1 discloses a technique for joining a first member 10 and a second member 12 by sandwiching a joining material 2 containing indium and melting point depressants 1A and 1B for lowering the melting point of indium between the first member 10 and the second member 12 (paragraph

[0049] of Patent Document 1). Further, a technique for disposing an O-ring 23 as an airtight sealant inside the indium-containing joining layer 2 is disclosed (paragraph

[0063] of Patent Document 1).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the technology described in Patent Document 1, there is a risk of arcing occurring in the gap inside the O-ring 23. Furthermore, because indium has a low melting point, there is a risk of it melting and leaking out depending on the usage environment. The problem that the technology disclosed aims to solve is to provide a technology that suppresses the occurrence of arcing and prevents leakage of the bonding material. [Means for solving the problem]

[0007] A holding device according to the present disclosure comprises a plate-shaped member having a first surface, a base material, a metal bonding layer disposed between the base material and the plate-shaped member, a porous body, an annular member, and a gas flow path, wherein the gas flow path comprises a base material side gas flow path formed inside the base material, a plate-shaped member side gas flow path formed inside the plate-shaped member, a metal bonding layer side gas flow path formed inside the metal bonding layer, and an annular member side gas flow path formed inside the annular member and communicating with at least one of the base material side gas flow path and the plate-shaped member side gas flow path, the porous body is disposed inside the metal bonding layer side gas flow path when viewed from a first direction perpendicular to the first surface, and covers at least a portion of the porous body. [Effects of the Invention]

[0008] The holding device of this disclosure can suppress the occurrence of arcing and prevent leakage of the bonding material. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a perspective view showing the electrostatic chuck 100 of the first embodiment. [Figure 2] Figure 2 is a cross-sectional view showing the internal structure of the electrostatic chuck 100 shown in Figure 1. [Figure 3] Figure 3 is a plan view showing the periphery of the cylindrical member 140 of the electrostatic chuck 100 according to the first embodiment. [Figure 4] Figure 4 is a cross-sectional view showing the periphery of the cylindrical member 140 of the electrostatic chuck 100 according to the first embodiment. [Figure 5] Figure 5 is a cross-sectional view showing the internal structure of the electrostatic chuck 200 of the second embodiment. [Figure 6] Figure 6 is a cross-sectional view showing the periphery of the metal bonding layer 230 of the electrostatic chuck 200 of the second embodiment. [Figure 7] Figure 7 shows the projection region in the electrostatic chuck 200 of the second embodiment, where the second metal bonding layer 232, the annular member 233, and the porous body 250 are projected onto the upper surface 220a of the plate-shaped member 220. [Figure 8] Figure 8 is a cross-sectional view showing the periphery of the metal bonding layer 330 of the electrostatic chuck 300 in a first modified example of the second embodiment. The electrostatic chuck 300 includes a base material 210, a plate-shaped member 220, a metal bonding layer 330, a cylindrical member 240, and a porous body 350. [Figure 9] Figure 9 shows the projection region in the electrostatic chuck 300 in the first modified example of the second embodiment, where the second metal bonding layer 232, the annular member 333, and the porous body 350 are projected onto the upper surface 220a of the plate-shaped member 220. [Figure 10] Figure 10 is a cross-sectional view showing the periphery of the metal bonding layer 430 of the electrostatic chuck 400 in a second modified example of the second embodiment. [Figure 11] Figure 11 shows the projection region in the electrostatic chuck 400 in a second modified example of the second embodiment, where the second metal bonding layer 232, the annular member 433, and the porous body 250 are projected onto the upper surface 220a of the plate-shaped member 220. [Figure 12] Figure 12 is a cross-sectional view showing the periphery of the porous body 550 of the electrostatic chuck 500 according to the third embodiment. [Figure 13] Figure 13 is a schematic diagram showing the cross-sectional structure of the porous body 550 of the electrostatic chuck 500 of the third embodiment. [Figure 14] Figure 14 is a schematic diagram showing the gas flow inside the porous body 550 in the electrostatic chuck 500 of the third embodiment. [Figure 15]FIG. 15 is a cross-sectional view showing the periphery of the porous body 550 of the electrostatic chuck 600 in the first modification of the third embodiment. [Figure 16] FIG. 16 is a cross-sectional view showing the periphery of the porous body 550 of the electrostatic chuck 700 in the second modification of the third embodiment. [Figure 17] FIG. 17 is a cross-sectional view showing the periphery of the porous body 850 of the electrostatic chuck 800 in the third modification of the third embodiment. [Figure 18] FIG. 18 is a diagram schematically showing the gas flow inside the porous body 850 of the electrostatic chuck 800 in the third modification of the third embodiment.

Embodiments for Carrying Out the Invention

[0010] [Details of Embodiments of the Present Disclosure] Embodiments of the present disclosure will be listed and described.

[0011] (1) The holding device of the present disclosure is a holding device having a plate-like member having a first surface, a base material, a metal bonding layer disposed between the base material and the plate-like member, a porous body, an annular member, and a gas flow path. The gas flow path includes a base material side gas flow path formed inside the base material, a plate-like member side gas flow path formed inside the plate-like member, a metal bonding layer side gas flow path formed inside the metal bonding layer, and an annular member side gas flow path formed inside the annular member and communicating with at least one of the base material side gas flow path and the plate-like member side gas flow path. The porous body is disposed inside at least one of the base material side gas flow path and the plate-like member side gas flow path. The annular member is disposed inside the metal bonding layer side gas flow path when viewed from a first direction perpendicular to the first surface, and covers at least a part of the porous body.

[0012] (2) In the holding device of (1) above, a part of the porous body is disposed inside the annular member side gas flow path of the annular member.

[0013] (3) In the holding device of (1) or (2) above, the annular member is ring-shaped, and the porous body is cylindrical.

[0014] (4) In the holding device described in (3) above, the outer diameter of the annular member is larger than the outer diameter of the porous body.

[0015] (5) In the holding device described in any of (1) to (4) above, the material of the annular member is resin.

[0016] [Details of the embodiments of this disclosure] The following describes specific embodiments, using a holding device for holding semiconductor wafers and the like in a semiconductor processing apparatus as an example, with reference to the figures. A semiconductor processing apparatus, for example, uses plasma to deposit a semiconductor film on a semiconductor wafer or to etch a semiconductor. However, the technology described herein is not limited to these embodiments. Furthermore, the thicknesses of each layer in the drawings do not necessarily represent the ratio of actual thicknesses.

[0017] In this disclosure, the holding device has a gas channel. The gas channel includes at least a portion of the substrate-side gas channel, the plate-shaped member-side gas channel, the bonding layer-side gas channel, the cylindrical member-side gas channel, the annular member-side gas channel, and the porous body-side gas channel.

[0018] (First Embodiment) A first embodiment will now be described. As will be described later, the first embodiment is characterized by a cylindrical member arranged on a plate-shaped member.

[0019] 1. Electrostatic chuck Figure 1 is a perspective view showing the electrostatic chuck 100 of the first embodiment. Figure 2 is a cross-sectional view showing the internal structure of the electrostatic chuck 100 of Figure 1.

[0020] The electrostatic chuck 100 is a holding device for holding a semiconductor wafer W1 in a semiconductor processing apparatus. The electrostatic chuck 100 can also hold glass substrates and the like. The electrostatic chuck 100 can attract and hold semiconductor wafers and the like when performing plasma processing on semiconductor wafers and the like in a reduced-pressure chamber.

[0021] The electrostatic chuck 100 includes a base material 110, a plate-shaped member 120, a bonding layer 130, a cylindrical member 140, and a porous body 150. As shown in Figure 1, the plate-shaped member 120 has a mounting surface 120c. The mounting surface 120c is the surface on which the semiconductor wafer W1 is mounted.

[0022] 2. Gas flow path The electrostatic chuck 100 has a gas channel FPA. The gas channel FPA is a channel for supplying gas to space SP1. The gas supplied to space SP1 is an inert gas such as helium gas. By supplying the inert gas to space SP1 facing the back surface of the semiconductor wafer W1, the temperature distribution of the semiconductor wafer W1 is kept almost uniform across the surface.

[0023] The gas flow path FPA comprises a base material side gas flow path FPA1, a plate-shaped member side gas flow path FPA2, a bonding layer side gas flow path FPA3, and a cylindrical member side gas flow path FPA4. The base material side gas flow path FPA1 is formed inside the base material 110. The plate-shaped member side gas flow path FPA2 is formed inside the plate-shaped member 120. The bonding layer side gas flow path FPA3 is formed inside the bonding layer 130. The cylindrical member side gas flow path FPA4 is formed inside the cylindrical member 140. In the gas flow path FPA, the gas flow paths are arranged in the order of base material side gas flow path FPA1, bonding layer side gas flow path FPA3, plate-shaped member side gas flow path FPA2, and cylindrical member side gas flow path FPA4 from the base material 110 side. The plate-shaped member side gas flow path FPA2 includes the cylindrical member side gas flow path FPA4.

[0024] A gas channel FPA2, through which a gas such as helium flows, is formed inside the plate-shaped member 120. The gas channel FPA2 consists of vertical and horizontal holes. An outlet communicating with the gas channel FPA2 is formed on the surface of the plate-shaped member 120. Gas supplied to the gas channel FPA2 from a gas supply source (not shown) is discharged from the outlet via the vertical and horizontal holes. This introduces the gas into the space SP1 between the semiconductor wafer W1 and the plate-shaped member 120.

[0025] 3. Base material The base material 110 has a refrigerant channel 111, a gas channel FPA1, and a porous body 150. The refrigerant channel 111 is a channel for flowing a refrigerant to cool the base material 110. The gas channel FPA1 is in communication with the gas channel FPA2 of the plate-shaped member 120, which will be described later.

[0026] The base material 110 is disc-shaped. The diameter of the base material 110 is larger than the diameter of the plate-shaped member 120 so that the entire plate-shaped member 120 can be placed on it.

[0027] The substrate 110 has an upper surface 110a and a lower surface 110b. The lower surface 110b is the surface opposite to the upper surface 110a. The semiconductor wafer W1 will be placed on the side of the upper surface 110a of the substrate 110. The plate-shaped member 120 is arranged on the side of the upper surface 110a of the substrate 110.

[0028] The base material 110 is a component mainly composed of aluminum, an aluminum alloy, a composite of metal and ceramics (Al-SiC), or ceramics (SiC). When the base material 110 is mainly composed of Al-SiC, for example, the aluminum component (weight %) is in the range of 30 ≤ Al ≤ 90 (e.g., 30 wt%), and the silica component (weight %) is in the range of 10 ≤ Si ≤ 70 (e.g., 70 wt%).

[0029] The thermal expansion coefficient of the base material 110 is in the range of 5 ppm / °C to 9 ppm / °C (e.g., 6.9 ppm / °C), and its thermal conductivity is 180 W / m·K, which is higher than that of the plate-shaped member 120. By using materials with the above-described composition as the materials for the plate-shaped member 120 and the base material 110, the difference in thermal expansion coefficients between the plate-shaped member 120 and the base material 110 is within 5 ppm / °C (e.g., 0.7 ppm / °C), which is a very small value.

[0030] 4. Plate-shaped member The plate-shaped member 120 is a component that adsorbs the semiconductor wafer W1 with an internal chuck electrode 122 and uniformly controls the temperature distribution of the semiconductor wafer W1 with a heater electrode 123, which will be described later.

[0031] The plate-shaped member 120 comprises a base material 121, a chuck electrode 122 positioned between the heater electrode 123 and the upper surface 120a inside the plate-shaped member 120, a heater electrode 123 positioned inside the plate-shaped member 120, and a cylindrical member 140. The chuck electrode 122 and the heater electrode 123 are arranged side by side in the vertical direction, with the chuck electrode 122 positioned closer to the upper surface 120a and the heater electrode 123 positioned below the chuck electrode 122.

[0032] The plate-shaped member 120 has an upper surface 120a and a lower surface 120b. The upper surface 120a of the plate-shaped member 120 is, for example, the first surface. The lower surface 120b of the plate-shaped member 120 is, for example, the second surface. The lower surface 120b is the surface opposite to the upper surface 120a. The base material 110 is positioned facing the lower surface 120b of the plate-shaped member 120.

[0033] The upper surface 120a of the plate-shaped member 120 may have a plurality of protrusions. The plurality of protrusions may be arranged concentrically, or on the grid points of an equilateral triangle or square. The pitch spacing between the protrusions is, for example, 1 mm or more and 20 mm or less. If the pitch is too large, the semiconductor wafer W1 may bend due to electrostatic attraction force and come into contact with the plate-shaped member 120. If the pitch is too small, the area in contact between the semiconductor wafer W1 and the gas will be reduced, which may cause an uneven distribution of the in-plane temperature of the semiconductor wafer W1.

[0034] The height of the protrusion is, for example, 30 μm or less. Preferably, it is between 5 μm and 15 μm. The angle θ between the top surface and the side surface of the protrusion is, for example, between 90° and 170°. The angle θ can be adjusted by the processing method.

[0035] The base material 121 of the plate-shaped member 120 is mainly composed of alumina, aluminum nitride, yttria, or a composite material of alumina and silicon carbide. The thermal expansion coefficient of the base material 121 of the plate-shaped member 120 is in the range of 6 ppm / °C to 8 ppm / °C (for example, 7.6 ppm / °C), and its thermal conductivity is 18 W / (m·K).

[0036] 4-1. Chuck electrode The chuck electrode 122 is mainly composed of tungsten, molybdenum, or an alloy thereof. The chuck electrode 122 exhibits electrostatic attraction force when a voltage is applied. As for the type of electrostatic attraction force, Coulomb force, Johnsen-Rabec force, or gradient force can be used. In the first embodiment, the chuck electrode 122 uses a metallized conductor layer on which a conductive paste has been printed and sintered, but metal foil, metal mesh, etc. may also be used.

[0037] The chuck electrode 122 is positioned at a distance of 0.05 mm to 4 mm from the upper surface 120a of the plate-shaped member 120. Preferably, the distance is 0.2 mm to 1 mm. The chuck electrode 122 is, for example, a bipolar electrode with crescent-shaped electrodes facing each other.

[0038] 4-2. Heater electrodes The heater electrode 123 is mainly composed of tungsten, molybdenum, or alloys thereof, or carbides thereof. Although the heater electrode 123 is located inside the plate-shaped member 120, it may also be located on the surface of the plate-shaped member 120 or inside a separate heater member (polyimide heater) from the plate-shaped member 120. In the first embodiment, the heater electrode 123 uses a metallized conductive layer on which a conductive paste has been printed and sintered, but metal foil, metal mesh, etc., may also be used.

[0039] The chuck electrode 122 and the heater electrode 123 are electrically connected to a power supply (not shown) by wiring (not shown).

[0040] 5.Joining layer The bonding layer 130 adheres the base material 110 and the plate-shaped member 120. The bonding layer 130 is positioned between the upper surface 110a of the base material 110 and the lower surface 120b of the plate-shaped member 120. The main component of the bonding layer 130 is, for example, indium, aluminum, silicone resin, or epoxy resin. If the main component of the bonding layer 130 is aluminum, the bonding layer 130 may also contain Si or Mg as minor components. For example, a paste-like or sheet-like adhesive may be used as the bonding layer 130.

[0041] In addition to bonding the base material 110 and the plate-shaped member 120, the bonding layer 130 also plays a role in conducting heat between the base material 110 and the plate-shaped member 120, and in relieving stress caused by thermal expansion between the base material 110 and the plate-shaped member 120.

[0042] 6. Cylindrical member Figure 3 is a plan view showing the periphery of the cylindrical member 140 of the electrostatic chuck 100 of the first embodiment. Figure 4 is a cross-sectional view showing the periphery of the cylindrical member 140 of the electrostatic chuck 100 of the first embodiment. Note that Figure 4 shows a cross-section of the plate-shaped member 120 without the lateral holes of the plate-shaped member side gas flow path FPA2.

[0043] The cylindrical member 140 has a cylindrical shape. The cylindrical member 140 is located inside the base material 121 of the plate-shaped member 120. The cylindrical member 140 is located in the middle of the plate-shaped member side gas flow path FPA2 of the plate-shaped member 120. The cylindrical member 140 has a cylindrical member side gas flow path FPA4. The cylindrical member side gas flow path FPA4 has a cylindrical member side first opening A1 and a cylindrical member side second opening A2, which will be described later, and connects the cylindrical member side first opening A1 and the cylindrical member side second opening A2. The plate-shaped member side gas flow path FPA2 includes the cylindrical member side gas flow path FPA4.

[0044] The outer diameter of the cylindrical member 140 is, for example, 20 mm or less. The length between the upper surface 140a and the lower surface 140b of the cylindrical member 140 is, for example, 10 mm or less.

[0045] The cylindrical member 140 is made of a material that is easier to process than the base material 121 of the plate-shaped member 120. The material of the cylindrical member 140 is, for example, machinable ceramics. The material of the cylindrical member 140 preferably has layered crystals. The material of the cylindrical member 140 preferably has cleavage planes. Materials with cleavage planes have the property of cracking along the cleavage planes. Because the cylindrical member 140 is made of a material with excellent processability, small diameter through holes can be machined into the cylindrical member 140. The material of the cylindrical member 140 is, for example, a material made of AlN and BN. Alternatively, it may be an Al2O3-SiO2 system material. For example, it may be Macol® or Hotover®. AlN-BN is particularly preferred because it has excellent processability and excellent thermal conductivity.

[0046] The Vickers hardness of the cylindrical member 140 is, for example, 2 GPa or more and 7 GPa or less. The Vickers hardness of the cylindrical member 140 may be 3 GPa or more and 6 GPa or less. The Vickers hardness of the cylindrical member 140 is 20% or more and 80% or less of the Vickers hardness of the base material 121 of the plate-shaped member 120. The Vickers hardness of the cylindrical member 140 may be 30% or more and 70% or less of the Vickers hardness of the base material 121 of the plate-shaped member 120.

[0047] The Young's modulus of the cylindrical member 140 is, for example, 100 GPa or more and 280 GPa or less. The Young's modulus of the cylindrical member 140 may be 150 GPa or more and 250 GPa or less. The Young's modulus of the cylindrical member 140 is 20% or more and 80% or less of the Young's modulus of the base material 121 of the plate-shaped member 120. The Young's modulus of the cylindrical member 140 may be 30% or more and 70% or less of the Young's modulus of the base material 121 of the plate-shaped member 120.

[0048] The thermal conductivity of the cylindrical member 140 is, for example, 50 W / (m·K) or more and 130 W / (m·K) or less. The thermal conductivity of the cylindrical member 140 may be 60 W / (m·K) or more and 120 W / (m·K) or less. The thermal conductivity of the cylindrical member 140 is 50% or more of the thermal conductivity of the base material 121 of the plate-shaped member 120. The thermal conductivity of the cylindrical member 140 may be 60% or more of the thermal conductivity of the base material 121 of the plate-shaped member 120. The cylindrical member 140 is denser than the porous body 150. That is, the porosity of the cylindrical member 140 is lower than the porosity of the porous body 150. And the thermal conductivity of the cylindrical member 140 is higher than the thermal conductivity of the porous body 150.

[0049] The cylindrical member 140 has a through hole X1. The through hole X1 is formed from the upper surface 140a to the lower surface 140b of the cylindrical member 140. The through hole X1 is the gas passage FPA4 on the cylindrical member side. The inner diameter of the through hole X1 is, for example, 0.1 mm or less. Preferably, it is 0.02 mm or more and 0.06 mm or less. This through hole X1 can be machined using, for example, an electroplated grinding wheel, a diamond-coated drill, a laser, etc. Note that the cylindrical member 140 may have multiple through holes X1.

[0050] A hole X2 is formed in the base material 121 of the plate-shaped member 120. The hole X2 has a first opening B1 on the base material side and a second opening B2 on the base material side. That is, the base material 121 has a first opening B1 on the base material side and a second opening B2 on the base material side. The hole X2 constitutes a gas flow path FPA2 on the plate-shaped member side. The gas flow path FPA2 on the plate-shaped member side connects the first opening B1 on the base material side and the second opening B2 on the base material side.

[0051] The cylindrical member 140 has a first opening A1 on the cylindrical member side and a second opening A2 on the cylindrical member side. The base material 121 has a first opening B1 on the base material side and a second opening B2 on the base material side. The first opening A1 on the cylindrical member side of the cylindrical member 140 is located on the side of the first opening B1 on the base material side of the base material 121. The second opening A2 on the cylindrical member side of the cylindrical member 140 is located on the side of the second opening B2 on the base material side of the base material 121. Furthermore, the second opening A2 on the cylindrical member side of the cylindrical member 140 is located on the side of the porous body 150.

[0052] The inner diameter of the first opening A1 on the cylindrical member side is, for example, 0.1 mm or less. The inner diameter of the second opening A2 on the cylindrical member side is, for example, 0.1 mm or less.

[0053] The upper surface 120a of the plate-shaped member 120 has the upper surface 121a of the base material 121 and the upper surface 140a of the cylindrical member 140. The surface roughness of the upper surface 140a of the cylindrical member 140 is rougher than the surface roughness of the upper surface 121a of the base material 121 of the plate-shaped member 120. The upper surface 140a of the cylindrical member 140 is, for example, the first cylindrical member surface. The upper surface 121a of the base material 121 is, for example, the first base material surface. The thermal conductivity of the cylindrical member 140 is lower than that of the base material 121. Because the surface roughness of the cylindrical member 140 is rough, the surface area of ​​the cylindrical member 140 is relatively large. Therefore, the heat transfer performance of the cylindrical member 140 may be improved. The upper surface 121a of the base material 121 surrounds the periphery of the upper surface 140a of the cylindrical member 140.

[0054] The cylindrical member 140 is integral with the base material 121 of the plate-shaped member 120. In other words, the base material 121 and the cylindrical member 140 are manufactured by firing them at the same time. Therefore, there is no joining material between the base material 121 and the cylindrical member 140.

[0055] 7. Porous material The porous body 150 is positioned inside a portion of the substrate-side gas channel FPA1. That is, the interior of the substrate-side gas channel FPA1 of the substrate 110 is filled with the porous body 150. The porous body 150 is a gas-permeable member containing numerous pores, mainly composed of insulating ceramics. The porous body 150 is cylindrical overall.

[0056] Inside the porous body 150, a network of ventilation channels is formed to allow inert gas to pass through. These ventilation channels consist of numerous interconnected pores within the porous body 150. The pores are formed as traces left behind when particulate pore-forming material disappears during the manufacturing (firing) of the porous body 150. Examples of pore-forming materials include synthetic resin beads and carbon powder.

[0057] The outer diameter of the porous body 150 is larger than the outer diameter of the cylindrical member 140. The thermal conductivity of the cylindrical member 140 is lower than that of the base material 121. Therefore, considering the in-plane temperature distribution of the plate-shaped member 120, a smaller outer diameter of the cylindrical member 140 is preferable. The larger the outer diameter of the porous body 150, the greater the flow rate of gas delivered to the gas channel FPA2 on the plate-shaped member side. Therefore, a larger outer diameter of the porous body 150 is preferable.

[0058] 8. Effects of the First Embodiment The electrostatic chuck 100 of the first embodiment has a base material 121 and a cylindrical member 140. The cylindrical member 140 is made of a material that is easier to process than the base material 121. Therefore, a through hole X1 with a small inner diameter can be machined into the cylindrical member 140. Because the diameter of the through hole X1 is very small, arcing is less likely to occur.

[0059] 9. Variations 9-1. Arrangement method of cylindrical members In the first embodiment, the cylindrical member 140 of the electrostatic chuck 100 is integral with the base material 121. However, the cylindrical member 140 may be bonded to the base material 121. The cylindrical member 140 may be press-fitted into the base material 121. The cylindrical member 140 may be shrink-fitted or cold-fitted into the base material 121.

[0060] 9-2. Position of the cylindrical member In the electrostatic chuck 100 of the first embodiment, the upper surface 120a of the plate-shaped member 120 has the upper surface 121a of the base material 121 and the upper surface 140a of the cylindrical member 140. However, the upper surface 140a of the cylindrical member 140 may protrude beyond the upper surface 121a of the base material 121. Also, the upper surface 140a of the cylindrical member 140 may be recessed from the upper surface 121a of the base material 121. The upper surface 140a of the cylindrical member 140 may be located further away from or closer to the upper surface 121a of the base material 121 when viewed from the lower surface 120b of the plate-shaped member 120.

[0061] 9-3. Conductive Film A conductive film may be formed between the substrate 110 and the bonding layer 130. This conductive film can be used as an electrode for generating plasma in a semiconductor processing apparatus.

[0062] 9-4. Combinations Modifications of the first embodiment may be freely combined.

[0063] (Second Embodiment) A second embodiment will now be described. As will be described later, the second embodiment is characterized by an annular member arranged in the metal bonding layer. The differences from the first embodiment will be explained in detail.

[0064] 1. Electrostatic chuck Figure 5 is a cross-sectional view showing the internal structure of the electrostatic chuck 200 of the second embodiment. The electrostatic chuck 200 includes a base material 210, a plate-shaped member 220, a metal bonding layer 230, a cylindrical member 240, and a porous body 250. The base material 210 includes a refrigerant flow path 211 and the porous body 250. The plate-shaped member 220 includes the cylindrical member 240. The base material 210 and the plate-shaped member 220 are joined by the metal bonding layer 230.

[0065] Figure 6 is a cross-sectional view showing the periphery of the metal bonding layer 230 of the electrostatic chuck 200 of the second embodiment. The base material 210 has an upper surface 210a and a lower surface 210b. The plate-like member 220 has an upper surface 220a and a lower surface 220b. The upper surface 210a of the base material 210 and the lower surface 220b of the plate-like member 220 are positioned facing each other.

[0066] The metal bonding layer 230 joins the base material 210 and the plate-shaped member 220. Therefore, the metal bonding layer 230 is positioned between the base material 210 and the plate-shaped member 220. The metal bonding layer 230 comprises a first metal bonding layer 231, a second metal bonding layer 232, and an annular member 233. The first metal bonding layer 231 has an upper surface 231a and a lower surface 231b. The second metal bonding layer 232 has an upper surface 232a and a lower surface 232b. The annular member 233 has an upper surface 233a and a lower surface 233b. The inner surface of the annular member 233 constitutes the annular member-side gas flow path FPB3.

[0067] The lower surface 231b of the first metal bonding layer 231 is in contact with the upper surface 210a of the base material 210. The upper surface 231a of the first metal bonding layer 231 is in contact with the lower surface 232b of the second metal bonding layer 232. The upper surface 232a of the second metal bonding layer 232 is in contact with the lower surface 221b of the base material 221 of the plate-shaped member 220.

[0068] The lower surface 233b of the annular member 233 faces the upper surface 250a of the porous body 250. The lower surface 233b of the annular member 233 may also be in contact with the upper surface 250a of the porous body 250. The upper surface 233a of the annular member 233 faces the lower surface 221b of the base material 221 of the plate-shaped member 220 and the lower surface 240b of the cylindrical member 240. The upper surface 233a of the annular member 233 may also be in contact with the lower surface 221b of the base material 221 of the plate-shaped member 220 and the lower surface 240b of the cylindrical member 240.

[0069] The cylindrical member 240 has an upper surface 240a and a lower surface 240b. The upper surface 220a of the plate-shaped member 220 has the upper surface 221a of the base material 221 and the upper surface 240a of the cylindrical member 240. The upper surface 240a of the cylindrical member 240 is connected to the upper surface 221a of the base material 221. The lower surface 240b of the cylindrical member 240 faces the upper surface 233a of the annular member 233. The lower surface 240b of the cylindrical member 240 may be in contact with the upper surface 233a of the annular member 233.

[0070] The porous body 250 has an upper surface 250a. The upper surface 250a of the porous body 250 faces the lower surface 233b of the annular member 233. The upper surface 250a of the porous body 250 may also be in contact with the lower surface 233b of the annular member 233.

[0071] 2. Gas flow path The electrostatic chuck 200 has a gas flow path FPB. The gas flow path FPB includes a base material side gas flow path FPB1, a plate-shaped member side gas flow path FPB2, a bonding layer side gas flow path FPB3, a cylindrical member side gas flow path FPB4, and an annular member side gas flow path FPB5.

[0072] The gas channel FPB2 on the plate-shaped member side includes the gas channel FPB4 on the cylindrical member side. Since the gas channel FPB4 is located immediately inside the gas channel FPB2 on the plate-shaped member side, gas does not pass immediately inside the gas channel FPB2 on the plate-shaped member side. The gas channel FPB3 on the bonding layer side includes the gas channel FPB5 on the annular member side.

[0073] The gas channel FPB5 on the annular member side is formed inside the annular member 233. The gas channel FPB5 on the annular member side is in communication with at least one of the gas channel FPB1 on the substrate side and the gas channel FPB2 on the plate-shaped member side.

[0074] No gas flows inside the second metal bonding layer 232. No gas flows in the space SP2 between the second metal bonding layer 232 and the annular member 233.

[0075] A porous body 250 is positioned in the middle of the substrate-side gas channel FPB1. Therefore, from the substrate 210 side, the substrate-side gas channel FPB1, the porous body 250, the bonding layer-side gas channel FPB3, and the cylindrical member-side gas channel FPB4 are arranged. In the second embodiment, the cylindrical member-side gas channel FPB4 occupies the inside of the plate-shaped member-side gas channel.

[0076] 3. Cylindrical member The cylindrical member 240 is made of a material that is easier to process than the base material 221 of the plate-shaped member 220. The length of the cylindrical member 240 from the upper surface 240a to the lower surface 240b is the same as the length of the base material 221 of the plate-shaped member 220 from the upper surface 221a to the lower surface 221b. Except for the length of the cylindrical member 240, the cylindrical member 240 may be the same as the cylindrical member 140 of the first embodiment. Alternatively, the cylindrical member 240 may not be provided, and a plate-shaped member side gas flow path FPB2 may be provided within the base material 221.

[0077] 4. Porous material The porous body 250 is positioned filled inside the gas channel FPB1 on the substrate side. The porous body 250 may also be positioned inside the gas channel FPB2 on the plate-shaped member side.

[0078] In the base material side gas channel FPB1 of the base material 210, a porous material chamber RM1 is formed on the side of the plate-shaped member 220. The porous material chamber RM1 is a chamber for arranging the porous material 250. The porous material chamber RM1 is a counterbore formed on the side of the upper surface 210a of the base material 210. The inner width of the porous material chamber RM1 is larger than the inner diameter of the base material side gas channel FPB1.

[0079] 5.Metal bonding layer The metal bonding layer 230 comprises a first metal bonding layer 231, a second metal bonding layer 232, and an annular member 233. The first metal bonding layer 231 is, for example, Al. The second metal alloy layer 232 is, for example, In. The first metal bonding layer 231 has through holes Y1 extending from the plate-shaped member 220 to the base material 210. The second metal bonding layer 232 has through holes Y2 extending from the plate-shaped member 220 to the base material 210.

[0080] The first metal bonding layer 231, the second metal bonding layer 232, and the plate-shaped member 220 are arranged in that order from the base material 210 side. The first metal bonding layer 231 is in contact with the upper surface 210a of the base material 210. The second metal bonding layer 232 is in contact with the lower surface 220b of the plate-shaped member 220.

[0081] The melting point of the second metal alloy layer 232 is lower than that of the first metal bonding layer 231. The melting point of the second metal alloy layer 232 is relatively low. On the other hand, the electrostatic chuck 200 is sometimes used at relatively high temperatures. Therefore, when the electrostatic chuck 200 is used in a semiconductor processing apparatus, there is a risk that the second metal alloy layer 232 may melt.

[0082] 6. Annular member The annular member 233 is annular in shape. The material of the annular member 233 is resin. Examples of materials for the annular member 233 include polyimide, silicone resin, and Kapton (registered trademark). It is preferable that the material of the annular member 233 has resistance to plasma.

[0083] The annular member 233 is positioned inside the through-hole Y2 of the second metal bonding layer 232. That is, the annular member 233 is positioned inside the bonding layer-side gas flow path FPB3 when viewed from the upper surface 220a of the plate-shaped member 220. The annular member 233 also covers at least a portion of the porous body 250. The annular member 233 and the second metal bonding layer 232 are positioned between the first metal bonding layer 231 on the base material 210 and the plate-shaped member 220.

[0084] The annular member 233 has an upper surface 233a and a lower surface 233b. The lower surface 233b is the surface opposite to the upper surface 233a and is positioned on the base material 210 side. The upper surface 233a of the annular member 233 faces the lower surface 220b of the plate-shaped member 220 and the lower surface 230b of the cylindrical member 240, and is in contact with the lower surface 220b of the plate-shaped member 220 and the lower surface 230b of the cylindrical member 240. The lower surface 233b of the annular member 233 faces the upper surface 231a of the first metal bonding layer 231 and the upper surface 250a of the porous body 250, and is in contact with the upper surface 231a of the first metal bonding layer 231 and the upper surface 250a of the porous body 250.

[0085] The distance between the upper surface 233a and the lower surface 233b of the annular member 233, i.e., the thickness of the annular member 233, is, for example, 0.15 mm or less. The outer diameter of the annular member 233 is, for example, 0.2 mm or more and 5.0 mm or less.

[0086] The inner surface of the annular member 233 constitutes the bonding layer-side gas flow path FPB3. The bonding layer-side gas flow path FPB3 is also the annular member-side gas flow path. The bonding layer-side gas flow path FPB3 is adjacent to the cylindrical member-side gas flow path FPB4 and communicates with the cylindrical member-side gas flow path FPB3.

[0087] Although the annular member 233 is in contact with the base material 210 and the plate-like member 220, it is not joined to the base material 210 and the plate-like member 220. Furthermore, although the annular member 233 faces the porous body 250 and covers the upper surface 250a of the porous body 250, it is not joined to the porous body 250.

[0088] 7. Peripheral structure of the annular member

[0089] Figure 7 shows the projection region of the electrostatic chuck 200 of the second embodiment, in which the second metal bonding layer 232, the annular member 233, and the porous body 250 are projected onto the upper surface 220a of the plate-shaped member 220. In Figure 7, the annular member 233 is drawn with a solid line, and the porous body 250 is drawn with a dashed line. As shown in Figure 7, the annular member 233 and the porous body 250 are arranged concentrically. Although not shown, it is preferable that the annular member 233 and the cylindrical member 240 are also arranged concentrically.

[0090] As shown in Figure 7, when the second metal bonding layer 232, the annular member 233, and the porous body 250 are projected onto the upper surface 220a of the plate-shaped member 220, the region onto which the second metal bonding layer 232 is projected is designated as the first projection region PR1, the region onto which the porous body 250 is projected is designated as the second projection region PR2, and the region onto which the annular member 233 is projected is designated as the third projection region PR3. At this time, a part of the third projection region PR3 exists between the first projection region PR1 and the second projection region PR2. The portion of the third projection region PR3 located between the first projection region PR1 and the second projection region PR2 is designated as the fourth projection region PR4.

[0091] The annular member 233 has a first portion R1. The first portion R1 corresponds to a fourth projection region PR4 when projected onto the upper surface 220a of the plate-shaped member 220. The first portion R1 is located on the outer circumference of the annular member 233.

[0092] Thus, when projected onto the upper surface 220a of the plate-shaped member 220, at least a portion of the annular member 233 exists between the easily meltable second metal bonding layer 232 and the porous body 250.

[0093] When the electrostatic chuck 200 is in use and the second metal bonding layer 232 melts, the molten metal flows into the space SP2. At this time, the first portion R1 of the annular member 233 blocks the molten metal. Therefore, there is almost no risk of the molten metal reaching the porous body 250.

[0094] The annular member 233 is circular in shape, and the porous body 250 is cylindrical. The outer diameter of the annular member 233 is larger than the outer diameter of the porous body 250.

[0095] As shown in Figure 6, the upper surface 232a of the second metal bonding layer 232 is bonded to the lower surface 220b of the plate-shaped member 220. The lower surface 232b of the second metal bonding layer 232 is bonded to the upper surface 231a of the first metal bonding layer 231. An annular member 233 is positioned inside the through-hole Y2 of the second metal bonding layer 232. Therefore, the space SP2 including the inner surface constituting the through-hole Y2 of the second metal bonding layer 232 is not in communication with the gas flow path FPB. The surface of the porous body 250 is not exposed to the space SP2. The porous body 250 is isolated from the second metal bonding layer 232 by the annular member 233.

[0096] Space SP2 is a closed space surrounded by the second metal bonding layer 232, the first metal bonding layer 231, the plate-like member 220, and the annular member 233. Space SP2 facing the through hole Y2 inside the second metal bonding layer 232 is sealed by the first metal bonding layer 231, the plate-like member 220, and the annular member 233. No gas flows through space SP2 facing the through hole Y2 inside the second metal bonding layer 232. Space SP2 facing the second metal bonding layer 232 and the gas flow path FPB are not in communication and are isolated. The annular member 233 acts as a partition separating space SP2 and the gas flow path FPB.

[0097] Furthermore, the inner diameter of the through-hole Y2 formed in the second metal bonding layer 232 is larger than the outer diameter of the porous body 250. For this reason, the first projection region PR1, which is the projection of the second metal bonding layer 232 onto the upper surface 220a of the plate-shaped member 220, and the second projection region PR2, which is the projection of the porous body 250 onto the upper surface 220a of the plate-shaped member 220, do not overlap.

[0098] 8. Effects of the second embodiment The electrostatic chuck 200 of the second embodiment includes a base material 210, a plate-shaped member 220, a metal bonding layer 230, and a porous body 250. The metal bonding layer 230 has a first metal bonding layer 231 and a second metal bonding layer 232. An annular member 233 is positioned between the porous body 250 and the second metal bonding layer 232. Therefore, even if the second metal bonding layer 232 melts slightly, the annular member 233 prevents the molten metal from reaching the porous body 250. Consequently, in the electrostatic chuck 200, there is almost no risk of the second metal bonding layer 232 filling the pores on the surface of the porous body 250.

[0099] 9. Manufacturing method A brief explanation of the manufacturing method for the electrostatic chuck 200 is provided. First, a first metal bonding layer 231 is bonded to the base material 210, and a porous body 250 is press-fitted into the porous body chamber RM1. Next, an annular member 233 is placed on top of the first metal bonding layer 231. The base material 221 and the cylindrical member 240, which are fired simultaneously, are bonded to this laminate with a second metal bonding layer 232. After this, the upper surface 220a of the plate-shaped member 220 is processed to form protrusions, etc. Then, through holes are formed in the cylindrical member 240, etc.

[0100] 10. Variations 10-1. First variation Figure 8 is a cross-sectional view showing the periphery of the metal bonding layer 330 of the electrostatic chuck 300 in a first modified example of the second embodiment. The electrostatic chuck 300 includes a base material 210, a plate-shaped member 220, a metal bonding layer 330, a cylindrical member 240, and a porous body 350.

[0101] The metal bonding layer 330 comprises a first metal layer 231, a second metal bonding layer 232, and an annular member 333. The annular member 333 is positioned inside the through-hole Y2 of the second metal bonding layer 232. A portion of the porous body 350 is positioned inside the annular member-side gas flow path FPB3 of the annular member 333. The upper surface 350a of the porous body 350 faces the lower surface 220b of the plate-shaped member 220 and the lower surface 240b of the cylindrical member 240. The upper surface 350a of the porous body 350 may also be in contact with the lower surface 220b of the plate-shaped member 220 and the lower surface 240b of the cylindrical member 240.

[0102] Figure 9 shows the projection region in the electrostatic chuck 300 in the first modified example of the second embodiment, where the second metal bonding layer 232, the annular member 333, and the porous body 350 are projected onto the upper surface 220a of the plate-shaped member 220.

[0103] As shown in Figure 9, when the second metal bonding layer 232, the annular member 333, and the porous body 350 are projected onto the upper surface 220a of the plate-shaped member 220, the region onto which the second metal bonding layer 232 is projected is designated as the first projection region PR1, the region onto which the porous body 350 is projected is designated as the second projection region PR2, and the region onto which the annular member 333 is projected is designated as the third projection region PR3. In this case, the third projection region PR3 exists between the first projection region PR1 and the second projection region PR2. The portion of the third projection region PR3 located between the first projection region PR1 and the second projection region PR2 is designated as the fourth projection region PR4. In the electrostatic chuck 300, the third projection region PR3 and the fourth projection region PR4 coincide.

[0104] Even in this case, the annular member 333 can block the molten metal.

[0105] 10-2. Second variation Figure 10 is a cross-sectional view showing the area around the metal bonding layer 430 of the electrostatic chuck 400 in a second modified example of the second embodiment. The electrostatic chuck 400 includes a base material 210, a plate-shaped member 220, a metal bonding layer 430, a cylindrical member 440, and a porous body 250.

[0106] The metal bonding layer 430 comprises a first metal layer 231, a second metal bonding layer 232, and an annular member 433. The annular member 433 is positioned inside the through-hole Y2 of the second metal bonding layer 232. The upper surface 250a of the porous body 250 faces the lower surface 220b of the plate-shaped member 220 and the lower surface 440b of the cylindrical member 440. The upper surface 250a of the porous body 250 may also be in contact with the lower surface 220b of the plate-shaped member 220 and the lower surface 440b of the cylindrical member 440.

[0107] Figure 11 shows the projection region in the electrostatic chuck 400 in a second modified example of the second embodiment, where the second metal bonding layer 232, the annular member 433, and the porous body 250 are projected onto the upper surface 220a of the plate-shaped member 220.

[0108] As shown in Figure 11, when the second metal bonding layer 232, the annular member 433, and the porous body 250 are projected onto the upper surface 220a of the plate-shaped member 220, the region onto which the second metal bonding layer 232 is projected is designated as the first projection region PR1, the region onto which the porous body 250 is projected is designated as the second projection region PR2, and the region onto which the annular member 433 is projected is designated as the third projection region PR3. In this case, the third projection region PR3 exists between the first projection region PR1 and the second projection region PR2. The portion of the third projection region PR3 located between the first projection region PR1 and the second projection region PR2 is designated as the fourth projection region PR4. The first portion R3 corresponding to the fourth projection region PR4 is located near the outer circumference of the annular member 433.

[0109] Even in this case, the annular member 433 can block the molten metal.

[0110] 10-3. Material of the second metal bonding layer The material of the second metal bonding layer 232 may be a metal or alloy other than In. For example, other indium-based materials, Al-based metals, Al-based alloys, Mg-based metals, Mg-based alloys, solder, brazing materials. The material of the second metal bonding layer 232 may also be other alloys. However, the melting point of the second metal bonding layer 232 is lower than the melting point of the first metal bonding layer 231.

[0111] 10-4. Material of the first metal bonding layer The material of the first metal bonding layer 231 may be a metal or alloy other than Al.

[0112] 10-5.Metal bonding layer The metal bonding layer 230 may consist only of the second metal bonding layer 232.

[0113] 10-6. Length of the cylindrical member The length of the cylindrical member 240 from its upper surface 240a to its lower surface 240b does not have to be the same as the length of the base material 221 of the plate-shaped member 220 from its upper surface 221a to its lower surface 221b.

[0114] 10-7. Combinations It may be acceptable to combine different variations.

[0115] (Third embodiment) A third embodiment will now be described. As will be described later, the third embodiment is characterized by a porous material. The differences from the first and second embodiments will be explained in detail.

[0116] 1. Electrostatic chuck Figure 12 is a cross-sectional view showing the periphery of the porous body 550 of the electrostatic chuck 500 of the third embodiment. The electrostatic chuck 500 includes a base material 210, a plate-shaped member 220, a metal bonding layer 330, a cylindrical member 240, and a porous body 550.

[0117] 2. Gas flow path The electrostatic chuck 500 has a gas channel FPC. The gas channel FPC includes a base material side gas channel FPC1, a plate-shaped member side gas channel FPC2, a bonding layer side gas channel FPC3, a cylindrical member side gas channel FPC4, an annular member side gas channel FPC5, and a porous body side gas channel FPC6. The plate-shaped member side gas channel FPC2 includes the cylindrical member side gas channel FPC4. The bonding layer side gas channel FPC3 includes the annular member side gas channel FPC5. Inside the bonding layer side gas channel FPC3 is the porous body side gas channel FPC6, and in practice, the gas passes through the porous body side gas channel FPC6. A porous body 550 is placed in the middle of the base material side gas channel FPC1. Therefore, from the base material 210 side, the base material side gas channel FPC1, the porous body 550, the porous body side gas channel FPC6, and the cylindrical member side gas channel FPC4 are arranged.

[0118] As shown in Figure 12, the gas channel FPC4 on the cylindrical member side and the gas channel FPC6 on the porous body side are in communication.

[0119] 3. Porous material Figure 13 is a schematic diagram showing the cross-sectional structure of the porous body 550 of the electrostatic chuck 500 of the third embodiment. The porous body 550 has an upper surface 550a, a lower surface 550b, and an outer surface 550c. The porous body 550 is cylindrical in shape, and the outer surface 550c is the outer surface of the cylinder. The material of the porous body 550 is the same as that of the porous body 150 of the first embodiment. The porous body 550 is gas permeable.

[0120] As shown in Figure 13, the porous body 550 has a bottomed hole Z1 formed in the direction from the upper surface 550a to the lower surface 550b. The bottomed hole Z1 is a hole that is open on the side of the upper surface 220a of the plate-shaped member 220 and closed on the opposite side of the upper surface 220a. After the porous body 550 is placed in the porous body chamber RM1 of the base material 210 and the base material 210 and the plate-shaped member 220 are joined, the upper surface 550a and the lower surface 550b of the porous body 550 are parallel to the upper surface 220a of the plate-shaped member 220 within the range of processing accuracy.

[0121] When length H is the length of the porous body 550 in a direction perpendicular to the upper surface 220a of the plate-shaped member 220, and length L is the depth of the porous body 550 from the upper surface 550a in the bottomed hole Z1 of the porous body 550, then length L and length H satisfy the following equation. H / 2 < L < H Length L is the length of the bottomed hole Z1 in a direction perpendicular to the upper surface 220a of the plate-shaped member 220.

[0122] Here, the inner diameter of the bottomed hole Z1 of the porous body 550 is preferably greater than or equal to the inner diameter of the through hole X1 of the cylindrical member 240. The inner diameter of the bottomed hole Z1 is, for example, 0.2 mm or less. The inner diameter of the through hole X1 is, for example, 0.1 mm or less. Alternatively, the inner diameter of the bottomed hole Z1 of the porous body 550 may be greater than or equal to the inner diameter of the gas flow path FPC2 on the plate-shaped member side.

[0123] The porous body-side gas channel FPC6, which is formed by the bottomed holes Z1 of the porous body 550, is in communication with the plate-shaped member-side gas channel FPC2 or the cylindrical member-side gas channel FPC4.

[0124] 4. Effects of the Third Embodiment Figure 14 is a schematic diagram showing the gas flow inside the porous body 550 in the electrostatic chuck 500 of the third embodiment. As shown in Figure 14, gas entering from the lower surface 550b of the porous body 550 passes through the interior of the porous body 550 and reaches the bottomed hole Z1. The gas exiting from the bottomed hole Z1 travels toward the upper surface 220a of the plate-shaped member 220.

[0125] Thus, the inner surface 550d and bottom surface 550e of the bottomed hole Z1 serve as gas outlets in the porous body 550. The surface area for gas outlets is sufficiently large. For this reason, the electrostatic chuck 500 of the third embodiment delivers a large flow rate of gas to the back surface of the semiconductor wafer W1 per unit time. For example, the gas flow rate in the electrostatic chuck 500 of the third embodiment is greater than the gas flow rate in the electrostatic chuck 200 of the second embodiment.

[0126] 5. Variations 5-1. First variation Figure 15 is a cross-sectional view showing the periphery of the porous body 550 of the electrostatic chuck 600 in a first modified example of the third embodiment. The electrostatic chuck 600 comprises a base material 210, a plate-shaped member 620, a metal bonding layer 330, and a porous body 550. The plate-shaped member 620 does not have a cylindrical member. That is, the electrostatic chuck 600 does not have a cylindrical member.

[0127] As shown in Figure 15, the gas channel FPC2 on the plate-shaped member side and the gas channel FPC6 on the porous body side are in communication.

[0128] Even in this case, the electrostatic chuck 600 can deliver a sufficient flow rate of gas to the back surface of the semiconductor wafer W1.

[0129] 5-2. Second Variation Figure 16 is a cross-sectional view showing the periphery of the porous body 550 of the electrostatic chuck 700 in a second modified example of the third embodiment. The electrostatic chuck 700 includes a base material 210, a plate-shaped member 720, a metal bonding layer 330, and a porous body 550. The plate-shaped member 720 does not have a cylindrical member. That is, the electrostatic chuck 700 does not have a cylindrical member.

[0130] As shown in Figure 16, a counterbore portion 721 is formed on the lower surface 720b of the plate-shaped member 720. Thus, the gas channel FPC2 on the plate-shaped member side has a counterbore portion 721 with a small diameter portion on the upper surface 720a side and a large diameter portion on the lower surface 720b side. Here, the inner diameter of the large diameter portion is larger than the inner diameter of the small diameter portion. The porous chamber RM2 is the space formed by combining the counterbore portion on the base material 210 side and the counterbore portion 721 on the plate-shaped member 720 side. As shown in Figure 16, the gas channel FPC2 on the plate-shaped member side and the gas channel FPC6 on the porous body side are in communication.

[0131] In the counterbore portion 721, the thickness between the upper surface 720a and surface 720c of the plate-shaped member 720 should be 0.5 mm or more. That is, the thickness of the large-diameter portion of the counterbore portion 721 in the direction perpendicular to the upper surface 720a is 0.5 mm or more. This thickness is the thickness of the counterbore portion 721 in the direction perpendicular to the upper surface 720a of the plate-shaped member 720.

[0132] Even in this case, the electrostatic chuck 700 can deliver a sufficient flow rate of gas to the back surface of the semiconductor wafer W1.

[0133] 5-3. Third Variation Figure 17 is a cross-sectional view showing the periphery of the porous body 850 of the electrostatic chuck 800 in a third modified example of the third embodiment. The electrostatic chuck 800 includes a base material 210, a plate-shaped member 820, a metal bonding layer 330, and a porous body 550. The plate-shaped member 820 does not have a cylindrical member. That is, the electrostatic chuck 800 does not have a cylindrical member.

[0134] As shown in Figure 17, a counterbore portion 821 is formed on the lower surface 820b of the plate-shaped member 820. The porous chamber RM2 is the space formed by combining the counterbore portion on the base material 210 side and the counterbore portion 821 on the plate-shaped member 820 side. As shown in Figure 17, the gas channel FPC2 on the plate-shaped member side and the gas channel FPC6 on the porous body side are in communication.

[0135] The porous body 850 has an upper surface 850a, a lower surface 850b, an outer surface 850c, an inner surface 850d, and a bottom surface 850e. An adhesive layer 860 is placed between the upper surface 850a of the porous body 850 and the surface 820c of the counterbore portion 821 of the plate-shaped member 820. The adhesive layer 860 adheres the plate-shaped member 820 and the porous body 850.

[0136] Furthermore, a point-shaped adhesive portion 870 is positioned between the lower surface 850c of the porous body 850 and the base material 210. The point-shaped adhesive portion 870 adheres the lower surface 850c of the porous body 850 to the base material 210 in a point-like manner. As a result, gas can flow into the surface of the outer surface 850c of the porous body 850.

[0137] Figure 18 is a schematic diagram showing the gas flow inside the porous body 850 of the electrostatic chuck 800 in a third modified example of the third embodiment.

[0138] The gas enters the porous body 850 from its lower surface 850c and outer surface 850c, and exits from its inner surface 850d and bottom surface 850e. In the electrostatic chuck 800 of the third modified example, the surface area for the gas to enter the porous body 850 is large, and the surface area for the gas to exit the porous body 850 is also large. Therefore, the electrostatic chuck 800 can deliver a sufficient flow rate of gas to the back surface of the semiconductor wafer W1 compared to the other electrostatic chucks of the third embodiment.

[0139] Thus, there is a gap between at least one of the substrate-side gas channel FPC1 and the plate-shaped member-side gas channel FPC2 and the outer surface 850c of the porous body 850. This gap is connected to the substrate-side gas channel FPC1 without passing through the porous body 850 and also constitutes a part of the gas channel FPC.

[0140] 5-4. Manufacturing method of the third modified example The surface 820c of the counterbore portion 821 of the plate-shaped member 820 and the upper surface 850a of the porous body 850 are bonded together with the adhesive layer 860. Next, a point-shaped adhesive portion 870 is placed on the bottom surface of the porous body chamber RM2 of the base material 210. Then, the base material 210 and the plate-shaped member 820 are joined together so that the porous body 850 is housed in the porous body chamber RM2.

[0141] 5-5. Variations of the third variation It is not necessary to provide the point-shaped adhesive portion 870. It is sufficient that the porous body 850 is bonded to the plate-shaped member 820 by the adhesive layer 860.

[0142] 5-6. Multiple drainage holes The holding device may have a plurality of plate-shaped member-side gas flow paths FPC2 and a plurality of bottomed holes Z1.

[0143] 5-7. Combinations You are free to combine each variation as you wish.

[0144] (Combination of embodiments) Except in cases where the structure of each part differs, the first to third embodiments may be freely combined, including variations.

[0145] (Gas flow path) One gas flow path may contain other gas flow paths. For example, in Figure 6, the cylindrical member gas flow path FPB4 is located immediately inside the plate-shaped member gas flow path FPB2. In this case, gas does not flow directly inside the plate-shaped member gas flow path FPB2, but gas flows into the cylindrical member gas flow path FPB4, which is further inside the plate-shaped member gas flow path FPB2. In this disclosure, even in such cases, or even when gas does not flow immediately inside as in the plate-shaped member gas flow path FPB2, the gas flow path will be defined as a flow path through which gas flows further inside via other members. [Explanation of Symbols]

[0146] 100, 200, 300, 400, 500, 600, 700, 800... Electrostatic chucks (holding devices) 110, 210...Base material 110a, 210a...Top surface, 110b, 210b...Bottom surface 120, 210, 620, 720, 820… Plate-shaped members 120a, 220a...Top surface 120b, 220b...Bottom surface 130…Joining layer 230, 330, 430…Metal joining layer 231...First metal bonding layer 232...Second metal bonding layer 233, 333, 334… Annular members 140, 240…Cylindrical members 150, 250, 350, 850... Porous material

Claims

1. A plate-shaped member having a first surface, Substrate and A metal bonding layer disposed between the substrate and the plate-shaped member, Porous material and Annular member and, gas flow path and In a holding device having, The aforementioned gas flow path is A gas channel on the substrate side formed inside the substrate, A gas flow path on the plate-shaped member side is formed inside the plate-shaped member, A metal bonding layer side gas channel formed inside the metal bonding layer, The annular member has an annular member-side gas passage formed inside the annular member and communicating with the base material-side gas passage and the plate-shaped member-side gas passage, The porous body Displaced inside at least one of the gas flow path on the substrate side and the gas flow path on the plate-shaped member side, The aforementioned annular member is When viewed from a first direction perpendicular to the first surface, it is located inside the metal bonding layer side gas flow path and is positioned between the substrate and the plate-shaped member. It covers at least a portion of the porous body, The aforementioned metal bonding layer is It comprises a first metal bonding layer, a second metal bonding layer, and the annular member, The first metal bonding layer is Al, The aforementioned second metal bonding layer is In. holding device.

2. In the holding device according to claim 1, When the second metal bonding layer, the porous body, and the annular member are projected onto the first surface of the plate-shaped member, and the region onto which the second metal bonding layer is projected is designated as the first projection region, the region onto which the porous body is projected is designated as the second projection region, and the region onto which the annular member is projected is designated as the third projection region, A portion of the third projection region exists between the first projection region and the second projection region. holding device.

3. In the holding device according to claim 1, Having a closed space surrounded by the first metal bonding layer, the second metal bonding layer, the plate-like member, and the annular member, holding device.

4. In the holding device according to claim 1, A part of the porous body, It is located inside the gas flow path on the annular member side of the annular member, When the second metal bonding layer, the porous body, and the annular member are projected onto the first surface of the plate-shaped member, and the region onto which the second metal bonding layer is projected is designated as the first projection region, the region onto which the porous body is projected is designated as the second projection region, and the region onto which the annular member is projected is designated as the third projection region, A third projection region exists between the first projection region and the second projection region. holding device.

5. In the holding device according to claim 1, The aforementioned annular member is It is located inside the through-hole of the second metal bonding layer, The surface of the porous body on the plate-like member side is, It faces the opposite side of the first surface of the plate-shaped member, When the second metal bonding layer, the porous body, and the annular member are projected onto the first surface of the plate-shaped member, and the region onto which the second metal bonding layer is projected is designated as the first projection region, the region onto which the porous body is projected is designated as the second projection region, and the region onto which the annular member is projected is designated as the third projection region, A third projection region exists between the first projection region and the second projection region. holding device.

6. In the holding device according to claim 1, A part of the porous body, Displaced inside the annular member side gas flow path of the annular member, holding device.

7. In the holding device according to claim 1, The aforementioned annular member is It is ring-shaped, The porous body It is cylindrical in shape. holding device.

8. In the holding device according to claim 7, The outer diameter of the annular member is, Larger than the outer diameter of the aforementioned porous body, holding device.

9. In the holding device according to claim 1, The material of the annular member is It is a resin. holding device.

10. In the holding device according to claim 1, The surface of the annular member on the substrate side is, The surface of the porous body facing the plate-like member side, The porous body is placed in the middle of the gas flow path on the substrate side. holding device.

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