Member for semiconductor fabrication apparatus

Abstract

A wafer chuck table 10 comprises: a ceramic plate 20 incorporating an electrostatic electrode 22; a base plate 30 incorporating a refrigerant channel 32; a through hole 34 penetrating the base plate 30 in a vertical direction at a position away from the center of the base plate 30; an insulating tube 50 inserted into the through hole 34; a power supply member 70 inserted into the insulating tube 50 and having a tip electrically connected to the electrostatic electrode 22; and an adhesive layer 60 having a first adhesive part 61 provided in a first gap G1 between the insulating tube 50 and the through hole 34 and a second adhesive part 62 provided in a second gap G2 between the insulating tube 50 and the power supply member 70. An undersurface 70b of the power supply member 70 is located below a bottom surface 30b of the refrigerant channel 32. An undersurface 61b of the first adhesive part 61 and / or an undersurface 62b of the second adhesive part 62 is located at the same height as or above a bottom surface 32b of the refrigerant channel 32.

Description

Member for semiconductor manufacturing equipment

[0001] The present invention relates to a member for a semiconductor manufacturing apparatus.

[0002] Conventionally, a member for a semiconductor manufacturing apparatus for processing a wafer placed on a wafer placement surface has been known. For example, the member for a semiconductor manufacturing apparatus described in Patent Document 1 has a wafer placement surface on its upper surface, an electrostatic chuck sheet incorporating an electrode, an aluminum susceptor adhered to the lower surface of the electrostatic chuck sheet, a through hole penetrating the susceptor in the vertical direction, an insulating tube inserted into the through hole, and a rod-shaped power supply member inserted into the insulating tube and having an upper end electrically connected to the electrode. The entire gap between the insulating tube and the through hole and the entire gap between the insulating tube and the power supply member are filled with an adhesive layer.

[0003] Japanese Patent Laid-Open No. 7-161803

[0004] However, when used in a high-temperature process or a high-power process, if the adhesive layer fills the entire gap between the insulating tube and the through hole and the entire gap between the insulating tube and the power supply member as in Patent Document 1, there may be an obstacle to the connection between the power supply member and the electrode.

[0005] The present invention has been made to solve such problems, and the main object is to suppress an obstacle to the connection between the power supply member and the electrode.

[0006] [1] The semiconductor manufacturing apparatus component of the present invention comprises: a ceramic plate having a wafer mounting surface on its upper surface and containing electrodes; a base plate provided on the lower surface of the ceramic plate and containing a refrigerant flow path; a base plate through hole that penetrates the base plate vertically at a position off-center from the base plate; an insulating tube inserted into the base plate through hole; a power supply member inserted into the insulating tube and having its tip electrically connected to the electrodes; and an adhesive layer having a first adhesive portion provided in a first gap between the insulating tube and the base plate through hole and a second adhesive portion provided in a second gap between the insulating tube and the power supply member, wherein the lower surface of the power supply member is below the bottom surface of the refrigerant flow path, and at least one of the lower surface of the first adhesive portion and the lower surface of the second adhesive portion is at the same height as or above the bottom surface of the refrigerant flow path.

[0007] In this semiconductor manufacturing equipment component, when heat is input from the wafer mounting surface side, it deforms in a convex shape upwards. The way in which the semiconductor manufacturing equipment component deforms at this time differs between the upper and lower sides, separated by a plane that includes the bottom surface of the refrigerant flow path. In this invention, at least one of the lower surfaces of the first adhesive portion and the second adhesive portion is at the same height as or above the bottom surface of the refrigerant flow path. Therefore, even if the way in which the semiconductor manufacturing equipment component deforms differs between the upper and lower sides, separated by a plane that includes the bottom surface of the refrigerant flow path, it is possible to suppress interference with the connection between the power supply component and the electrode as a result.

[0008] In this specification, the present invention may be described using terms such as up and down, left and right, front and back, but up and down, left and right, and front and back are merely relative positional relationships. Therefore, when the orientation of a semiconductor manufacturing equipment component is changed, up and down may become down and up, left and right, or front and back, but such cases are also included within the technical scope of the present invention.

[0009] [2] In the semiconductor manufacturing apparatus component of the present invention (the semiconductor manufacturing apparatus component described in [1] above), the absolute value of the difference in thermal expansion coefficients between the ceramic plate and the base plate at 40 to 570°C may be 1.0 ppm / K or less. This makes it possible to suppress interference with the connection between the power supply component and the electrode due to the difference in thermal expansion between the ceramic plate and the base plate.

[0010] [3] In the semiconductor manufacturing apparatus component of the present invention (the semiconductor manufacturing apparatus component described in [1] or [2] above), the lower surface of the first adhesive portion and the lower surface of the second adhesive portion may both be at the same height as or below the ceiling surface of the refrigerant flow path. In this case, heat at the position directly above the through-hole of the base plate is efficiently transferred to the refrigerant in the refrigerant flow path via the first and second adhesive portions, thereby improving the uniformity of the wafer's temperature.

[0011] [4] In the semiconductor manufacturing apparatus member of the present invention (the semiconductor manufacturing apparatus member described in any of [1] to [3] above), the lower surface of the first adhesive portion and the lower surface of the second adhesive portion may both be at the same height as or above the bottom surface of the refrigerant flow path. In this way, even if the amount of deformation of the semiconductor manufacturing apparatus member differs between the upper and lower sides of the bottom surface of the refrigerant flow path, it is possible to further suppress any interference with the connection between the power supply member and the electrode caused by this difference.

[0012] [5] In the semiconductor manufacturing apparatus component of the present invention (the semiconductor manufacturing apparatus component described in any of [1] to [4] above), the area of ​​the first gap may be smaller than the area of ​​the second gap in a plan view. This makes it easier to form a structure in which the lower surface of the second adhesive portion is above the lower surface of the first adhesive portion.

[0013] [6] In the semiconductor manufacturing apparatus component of the present invention (the semiconductor manufacturing apparatus component described in any of [1] to [5] above), the lower surface of the power supply member may be provided with a connector that can be connected to the tip of an external cable and may be located above the lower surface of the insulating tube, and the lower surface of the second adhesive portion may be located above the lower surface of the power supply member. In this way, the second adhesive portion is less likely to adhere to the connector on the lower surface of the power supply member.

[0014] [7] In the semiconductor manufacturing apparatus component of the present invention (the semiconductor manufacturing apparatus component described in any of [1] to [6] above), the thermal conductivity of the base plate may be 50 W / mK or more. In this case, the heat of the wafer is efficiently transferred to the refrigerant in the refrigerant flow path via the base plate, thereby improving the uniformity of the wafer's temperature.

[0015] [8] In the semiconductor manufacturing apparatus component of the present invention (the semiconductor manufacturing apparatus component described in any of [1] to [7] above), the thermal conductivity of the adhesive layer may be 0.5 W / mK or higher. In this case, the heat at the position directly above the through-hole of the base plate is efficiently transferred to the refrigerant in the refrigerant flow path via the first and second adhesive portions, thereby improving the uniformity of the wafer's temperature.

[0016] [9] In the semiconductor manufacturing apparatus component of the present invention (the semiconductor manufacturing apparatus component described in any of [1] to [8] above), the cross-sectional area of ​​the refrigerant flow path may be smaller in the region surrounding the base plate through-hole than in the region outside the region surrounding the base plate through-hole. This increases the flow velocity of the refrigerant flowing in the region surrounding the base plate through-hole of the refrigerant flow path. As a result, heat at the position directly above the base plate through-hole is efficiently transferred to the refrigerant in the refrigerant flow path, improving the uniformity of the wafer's temperature. In reducing the cross-sectional area of ​​the refrigerant flow path, for example, if the cross-section of the refrigerant flow path is rectangular, the width of the rectangle (horizontal length) may be shortened, or the height of the rectangle (vertical length) may be shortened.

[0017]

[10] In the semiconductor manufacturing apparatus component of the present invention (the semiconductor manufacturing apparatus component described in any of [1] to [9] above), the distance from the wafer mounting surface to the ceiling surface of the refrigerant flow path may be shorter in the region surrounding the base plate through hole than in the region outside the region surrounding the base plate through hole. In this case, heat at the position directly above the base plate through hole is efficiently transferred to the refrigerant in the refrigerant flow path, thereby improving the uniformity of the wafer's temperature.

[0018] Plan view of the wafer mounting table 10. Cross-sectional view along line A-A in Figure 1. Enlarged section of Figure 2. Cross-sectional view along line B-B in Figure 3. Explanatory diagram showing the bonding process of the insulating tube 50 in this embodiment. Enlarged section of the longitudinal cross-section of the wafer mounting table 910 (comparative form). Enlarged section of the longitudinal cross-section of another embodiment. Enlarged section of the longitudinal cross-section of another embodiment. Enlarged section of the longitudinal cross-section of another embodiment. Longitudinal cross-sectional view of another embodiment. Longitudinal cross-sectional view of another embodiment. Longitudinal cross-sectional view of another embodiment.

[0019] Preferred embodiments of the present invention will be described with reference to the drawings. Figure 1 is a plan view of the wafer mounting stage 10, Figure 2 is a cross-sectional view taken along line A-A in Figure 1, Figure 3 is a partially enlarged view of Figure 2 (enlarged view within the frame indicated by the dashed line), and Figure 4 is a cross-sectional view taken along line B-B in Figure 3.

[0020] The wafer mounting stage 10 is an example of a semiconductor manufacturing apparatus component of the present invention, and as shown in Figure 2, it comprises a ceramic plate 20, a base plate 30, a bonding layer 40, a base plate through hole 34, an insulating tube 50, an adhesive layer 60, and a power supply member 70.

[0021] The ceramic plate 20 is a ceramic disc (for example, 300 mm in diameter and 5 mm thick) made of an alumina sintered body or an aluminum nitride sintered body. The upper surface of the ceramic plate 20 is a wafer mounting surface 21 on which the wafer W is placed. The ceramic plate 20 incorporates electrostatic electrodes 22. On the wafer mounting surface 21 of the ceramic plate 20, although not shown in the figure, an annular sealing band is formed along the outer edge, and a plurality of small circular protrusions are formed on the entire inner surface of the sealing band. The electrostatic electrodes 22 are planar mesh electrodes and are connected to an external DC power supply (not shown) via a power supply member 70. When a DC voltage is applied to the electrostatic electrodes 22, the wafer W is attracted and fixed to the wafer mounting surface 21 by electrostatic attraction force, and when the application of the DC voltage is removed, the attraction and fixation of the wafer W to the wafer mounting surface 21 is released.

[0022] The base plate 30 is a disc with good electrical and thermal conductivity (for example, a disc with the same or larger diameter as the ceramic plate 20 and a thickness of 25 mm). A refrigerant flow path 32 is formed inside the base plate 30 through which the refrigerant circulates. The refrigerant flowing through the refrigerant flow path 32 is preferably a liquid and preferably electrically insulating. Examples of electrically insulating liquids include fluorine-based inert liquids. As shown in Figure 1, the refrigerant flow path 32 is formed in a spiral shape in a single continuous line across the entire base plate 30 in a plan view, from one end (inlet 32in) to the other end (outlet 32out). The inlet 32in and outlet 32out of the refrigerant flow path 32 are connected to a supply port and a recovery port of an external refrigerant device (not shown), respectively. The refrigerant supplied from the supply port of the external refrigerant device to the inlet 32in of the refrigerant flow path 32 passes through the refrigerant flow path 32 and returns to the recovery port of the external refrigerant device from the outlet 32out of the refrigerant flow path 32. After temperature adjustment, it is supplied again from the supply port to the inlet 32in of the refrigerant flow path 32. The base plate 30 is connected to a high-frequency (RF) power supply and is also used as an RF electrode.

[0023] The material of the base plate 30 can be, for example, a metal or a composite material of metal and ceramic. Examples of metal materials include Al, Ti, Mo, or alloys thereof. Examples of composite materials of metal and ceramic include metal matrix composites (MMC) and ceramic matrix composites (CMC). Specific examples of such composite materials include materials containing Si, SiC, and Ti (also called SiSiCTi), materials in which Al and / or Si are impregnated into a porous SiC body, and composite materials of Al2O3 and TiC. It is preferable to select a material for the base plate 30 that has a coefficient of thermal expansion (CTE) close to that of the ceramic plate 20.

[0024] Preferably, the absolute value of the CTE difference between the ceramic plate 20 and the base plate 30 at 40 to 570°C is 1.0 ppm / K or less. For example, if the material of the ceramic plate 20 is alumina (CTE at 40 to 570°C is 7.0 to 8.0 ppm / K), then the material of the base plate 30 is preferably AlSiC (SiC 75%) (CTE at 40 to 570°C is 7.0 to 9.0 ppm / K) or SiSiCTi (CTE at 40 to 570°C is 7.5 to 8.0 ppm / K). When the CTE at 0°C is 4.0 to 5.0 ppm / K, the base plate 30 is preferably made of Mo (CTE at 40 to 570°C is 5.0 to 6.0 ppm / K). The thermal conductivity of the base plate 30 is preferably 50 W / mK or higher. Examples of materials with a thermal conductivity of 50 W / mK or higher include the aforementioned AlSiC (75% SiC), AlSiC (85% SiC), and SiSiCTi.

[0025] The bonding layer 40 is a metal layer that joins the lower surface of the ceramic plate 20 to the upper surface of the base plate 30. The metal layer can be formed by a well-known thermal compression bonding (TCB) using a metal bonding material (e.g., an Al-Mg-based bonding material or an Al-Si-Mg-based bonding material).

[0026] The base plate through-hole 34 is a substantially cylindrical hole that penetrates the base plate 30 in the vertical direction, and is positioned off-center from the base plate 30 so as not to penetrate the refrigerant flow path 32. The base plate through-hole 34 communicates with the bonding layer through-hole 44. The bonding layer through-hole 44 is a substantially cylindrical hole that penetrates the bonding layer 40 in the vertical direction, and is positioned opposite the base plate through-hole 34. The opening edge of the base plate through-hole 34 may be chamfered.

[0027] The insulating tube 50 is housed in the through-hole 34 of the base plate and the through-hole 44 of the bonding layer. The insulating tube 50 is a substantially cylindrical member made of an electrically insulating material (for example, ceramic or resin), and has an insulating tube through-hole 54 that penetrates the insulating tube 50 vertically along its central axis. A first gap G1 is formed between the outer circumferential surface of the insulating tube 50 and the inner circumferential surface of the through-hole 34 in the base plate 30. A second gap G2 is formed between the inner circumferential surface of the insulating tube 50 and the outer circumferential surface of the power supply member 70. The insulating tube 50 is fixed to the through-hole 34 in the base plate 30 by the adhesive layer 60. As shown in Figure 4, the area S1 of the ring-shaped first gap G1 in plan view is smaller than the area S2 of the ring-shaped second gap G2. Also, the width w1 (radial length) of the first gap G1 is smaller than the width w2 of the second gap G2.

[0028] The power supply member 70 is a metal rod and is inserted into the insulating tube through hole 54 of the insulating tube 50. The power supply member 70 has a socket portion 72 on its lower surface 70b. The metal used for the power supply member 70 is preferably W, Mo, Ni, etc., and it is preferable that the thermal expansion coefficient of the metal is close to that of the ceramic plate 20. The socket portion 72 is a connector that can be connected to the end of the external cable 90. The external cable 90 is connected to a DC power supply for electrostatic adsorption (not shown). In this embodiment, the socket portion 72 can be used to insert and remove a plug 92 provided at the end of the external cable 90. For example, the socket portion 72 may be a banana socket and the plug 92 may be a banana plug. The lower surface 70b of the power supply member 70 is below the bottom surface 32b of the refrigerant flow path 32 and above the lower surface 50b of the insulating tube 50. The upper surface 70a of the power supply member 70 is electrically connected to the electrostatic electrode 22 exposed at the bottom of the hole 24 in the ceramic plate by a brazing material or the like. The hole 24 in the ceramic plate is a roughly cylindrical hole provided from the lower surface 23 of the ceramic plate 20 to the electrostatic electrode 22, and has a smaller diameter than the insulating tube through hole 54. The power supply member 70 is electrically insulated from the base plate 30 by the insulating tube 50.

[0029] The adhesive layer 60 has a first adhesive portion 61, a second adhesive portion 62, and a third adhesive portion 63. The upper surface 60a of the adhesive layer 60 (the upper surface of the first adhesive portion 61, the upper surface of the second adhesive portion 62, and the upper surface of the third adhesive portion 63) is in contact with the lower surface 23 of the ceramic plate 20. The first adhesive portion 61 is provided in the first gap G1. The lower surface 61b of the first adhesive portion 61 is above the bottom surface 32b of the refrigerant flow path 32 and below the top surface 32a of the refrigerant flow path 32. The second adhesive portion 62 is provided in the second gap G2. The lower surface 62b of the second adhesive portion 62 is above the bottom surface 32b of the refrigerant flow path 32 and below the top surface 32a of the refrigerant flow path 32. The lower surface 61b of the first adhesive portion 61 is below the lower surface 62b of the second adhesive portion 62. The third adhesive portion 63 is provided in the small gap between the upper surface 50a of the insulating tube 50 and the lower surface 23 of the ceramic plate 20. The third adhesive portion 63 is optional. In that case, the upper surface 50a of the insulating tube 50 and the lower surface 23 of the ceramic plate 20 are in contact. Examples of materials for the adhesive layer 60 include insulating resins such as epoxy resin, acrylic resin, and silicone resin. The adhesive layer 60 may also be an insulating resin containing a filler. The filler preferably has a higher thermal conductivity than the insulating resin of the adhesive layer 60, and may be alumina or aluminum nitride, for example. The thermal conductivity of the adhesive layer 60 is preferably 0.5 W / mK or higher. For example, a silicone resin containing alumina filler (thermal conductivity 2.2 W / mK) may be used as the adhesive layer 60. For example, the ceiling surface 32a of the refrigerant flow path 32 is formed at a location 1 to 8 mm from the lower surface of the bonding layer 40, preferably at a location 2 to 6 mm from the lower surface. Furthermore, for example, the distance from the top surface 32a of the refrigerant flow path 32 to the bottom surface 32b of the refrigerant flow path 32 may be 5 to 15 mm.

[0030] Next, the process of bonding the insulating tube 50, which is part of the manufacturing method of the wafer mounting table 10, will be explained using Figure 5. Figure 5 is an explanatory diagram of this process. In Figures 5A to 5C, the wafer mounting surface 21 of the ceramic plate 20 is facing downwards. Also, Figures 5A to 5C are enlarged partial views showing the area around the through-hole 34 of the base plate.

[0031] First, a joint is prepared in which a ceramic plate 20 and a base plate 30 are joined by a bonding layer 40 (Figure 5A). In this joint, electrostatic electrodes 22 are embedded in the ceramic plate 20. In this joint, a power supply member 70 is placed in the through-hole 34 of the base plate and the through-hole 44 of the bonding layer, and is also inserted through the closed-end hole 24 of the ceramic plate, and is electrically connected to the electrostatic electrodes 22. Next, adhesive 60x is placed on the lower surface 23 of the ceramic plate 20 (Figure 5B). Then, the insulating tube 50 is inserted into the through-hole 34 of the base plate so that the upper surface 50a of the insulating tube 50 faces the adhesive 60x. Next, when the insulating tube 50 is pushed towards the ceramic plate 20, the adhesive 60x crawls up through the gap between the lower surface 23 of the ceramic plate 20 and the upper surface 50a of the insulating tube 50, the first gap G1 between the inner circumferential surface of the base plate through hole 34 and the outer circumferential surface of the insulating tube 50, and the second gap G2 between the outer circumferential surface of the power supply member 70 and the inner circumferential surface of the insulating tube 50. Furthermore, when the insulating tube 50 is pushed towards the ceramic plate 20, the gap between the lower surface 23 of the ceramic plate 20 and the upper surface 50a of the insulating tube 50 narrows. Here, the width w1 of the first gap G1 is smaller than the width w2 of the second gap G2, and in plan view, the area S1 of the first gap G1 is smaller than the area S2 of the second gap G2 (see Figure 4). Therefore, the height to which the adhesive 60x crawls up through the first gap G1 is higher than the height to which it crawls up through the second gap G2. These heights are determined by the amount of adhesive 60x. In this state, as the adhesive 60x solidifies, the insulating tube 50 is bonded to the ceramic plate 20, the base plate 30, and the power supply member 70 via the adhesive layer 60 having the first adhesive portion 61 and the second adhesive portion 62. In this way, the wafer mounting stage 10 is obtained (Figure 5C).

[0032] Next, an example of using the wafer mounting stand 10 configured in this way will be described. First, with the wafer mounting stand 10 installed in a chamber (not shown), the wafer W is placed on the wafer mounting surface 21. Then, the pressure inside the chamber is reduced using a vacuum pump to adjust to a predetermined vacuum level, and a DC voltage is applied to the electrostatic electrode 22 of the ceramic plate 20 to generate electrostatic adsorption force, thereby adsorbing and fixing the wafer W to the wafer mounting surface 21. Next, the inside of the chamber is made into a reaction gas atmosphere with a predetermined pressure (for example, several tens to several hundreds of Pa), and in this state, an RF voltage is applied between an upper electrode (not shown) provided on the ceiling of the chamber and the base plate 30 of the wafer mounting stand 10 to generate plasma. The surface of the wafer W is treated by the generated plasma. Coolant is circulated in the coolant channel 32 of the base plate 30 as needed. When the wafer W is treated with plasma in this way, the heat input by the plasma is dissipated by the base plate 30, and the wafer mounting surface 21 is controlled to a desired temperature.

[0033] When processing the wafer W with plasma, the wafer mounting table 10 becomes hotter at the top and colder at the bottom due to the heat input from the plasma. As a result, the wafer mounting table 10 bends upwards, becoming convex. In other words, the wafer mounting table 10 bends into a shape where the center is higher and the outer edge gradually becomes lower. Since the power supply member 70 is located off-center from the wafer mounting table 10, it tilts diagonally with respect to the central axis of the wafer mounting table 10 as the wafer mounting table 10 bends into a convex shape.

[0034] The inventors performed a displacement analysis on the wafer mounting table 910 shown in Figure 6. The wafer mounting table 910 is a comparative configuration, in which the lower surface 961b of the first adhesive portion 961 and the lower surface 962b of the second adhesive portion 962 of the adhesive layer 960 are located below the bottom surface 32b of the refrigerant flow path 32. In the wafer mounting table 910 of Figure 5, the same reference numerals are used for the same components as in the wafer mounting table 10. When the upper part of the wafer mounting table 910 becomes hot and the lower part becomes cold, the wafer mounting table 910 bends into a convex shape. Analysis of the deformation at that time revealed that the way the wafer mounting table 10 deforms differs depending on whether the surface including the bottom surface 32b of the refrigerant flow path 32 (the dashed line in Figure 5) is the boundary. In the wafer mounting table 910, the power supply member 70 is fixed by the second adhesive portion 962 down to below the bottom surface 32b of the refrigerant flow path 32, and the insulating tube 50 is fixed by the first adhesive portion 961 down to below the bottom surface 32b of the refrigerant flow path 32. Therefore, if the deformation of the wafer mounting table 910 differs on either side of the plane including the bottom surface 32b of the refrigerant flow path 32, the deformation of both the power supply member 70 and the insulating tube 50 will change midway, and as a result, a shear force will act on the connection between the power supply member 70 and the electrostatic electrode 22. Since the connection between the power supply member 70 and the electrostatic electrode 22 is not very strong, there is a risk that the power supply member 70 may detach from the electrostatic electrode 22 when such a shear force is applied.

[0035] In contrast, in the wafer mounting table 10 of this embodiment, the lower surface 62b of the second adhesive portion 62 of the adhesive layer 60 is located above the bottom surface 32b of the refrigerant flow path 32. In other words, the portion of the power supply member 70 below the bottom surface 32b of the refrigerant flow path 32 is not fixed by the second adhesive portion 62 and is in a free state. Therefore, even if the way the wafer mounting table 10 deforms differs on either side of the plane including the bottom surface 32b of the refrigerant flow path 32 when the wafer mounting table 10 is bent into a convex shape, the way the power supply member 70 deforms does not change midway. Consequently, almost no shear force acts on the connection between the power supply member 70 and the electrostatic electrode 22. Also, the lower surface 61b of the first adhesive portion 61 of the adhesive layer 60 is located above the bottom surface 32b of the refrigerant flow path 32. In other words, the portion of the insulating tube 50 below the bottom surface 32b of the refrigerant flow path 32 is not fixed by the first adhesive portion 61 and is in a free state. Therefore, even if the wafer mounting base 10 deforms differently when it bends into a convex shape, depending on whether the wafer mounting base 10 deforms in the same way as the bottom surface 32b of the refrigerant flow path 32, neither the insulating tube 50 nor the power supply member 70 changes its deformation pattern along the way. Consequently, almost no shear force acts on the connection between the power supply member 70 and the electrostatic electrode 22.

[0036] As described above, the wafer mounting table 10 deforms upwards and becomes convex when heat is input from the wafer mounting surface 21. The way the wafer mounting table 10 deforms at this time differs between the upper and lower sides, separated by the plane including the bottom surface 32b of the refrigerant flow path 32. In this embodiment, both the lower surface 61b of the first adhesive portion 61 and the lower surface 62b of the second adhesive portion 62 are above the bottom surface 32b of the refrigerant flow path 32. Therefore, even if the way the wafer mounting table 10 deforms differs between the upper and lower sides, separated by the plane including the bottom surface 32b of the refrigerant flow path 32, it is possible to suppress interference with the connection between the power supply member 70 and the electrostatic electrode 22 as a result.

[0037] Furthermore, it is preferable that the absolute value of the difference in thermal expansion coefficients between the ceramic plate 20 and the base plate 30 at 40 to 570°C be 1.0 ppm / K or less. This prevents interference with the connection between the power supply member 70 and the electrostatic electrode 22 due to the difference in thermal expansion between the ceramic plate 20 and the base plate 30.

[0038] Furthermore, the lower surfaces 61b of the first adhesive portion 61 and 62b of the second adhesive portion 62 are both at the same height as or below the ceiling surface 32a of the refrigerant flow path 32. As a result, heat at the position directly above the base plate through hole 34 is efficiently transferred to the refrigerant in the refrigerant flow path 32 via the first and second adhesive portions 61 and 62, compared to the case where both the lower surfaces 61b of the first adhesive portion 61 and 62b of the second adhesive portion 62b are above the ceiling surface 32a of the refrigerant flow path 32. Therefore, the uniformity of heat distribution of the wafer W is improved.

[0039] Furthermore, in a plan view, the area S1 of the first gap G1 is smaller than the area S2 of the second gap G2. As a result, when bonding the insulating tube 50 with adhesive 60x (see Figure 5B), the amount of adhesive 60x that spreads up is greater in the first gap G1 than in the second gap G2. Consequently, it is easier to form a structure in which the lower surface 62b of the second bonding portion 62 is higher than the lower surface 61b of the first bonding portion 61.

[0040] Furthermore, the lower surface 70b of the power supply member 70 is equipped with a socket portion 72 (connector) that can be connected to the end of the external cable 90 and is located above the lower surface 50b of the insulating tube 50, and the lower surface 62b of the second adhesive portion 62 is located above the lower surface 70b of the power supply member 70. Therefore, the second adhesive portion 62 is less likely to adhere to the socket portion 72 on the lower surface 70b of the power supply member 70.

[0041] Furthermore, it is preferable that the thermal conductivity of the base plate 30 be 50 W / mK or higher. This allows the heat from the wafer W to be efficiently transferred to the refrigerant in the refrigerant channel 32 via the base plate 30, thereby improving the uniformity of the wafer W's temperature. Also, it is preferable that the thermal conductivity of the adhesive layer 60 be 0.5 W / mK or higher. This allows the heat directly above the base plate through-hole 34 to be efficiently transferred to the refrigerant in the refrigerant channel 32 via the adhesive layer 60 (first and second adhesive portions 61, 62), thereby improving the uniformity of the wafer W's temperature.

[0042] It goes without saying that the present invention is not limited in any way to the embodiments described above, and can be implemented in various forms as long as they fall within the technical scope of the present invention.

[0043] In the above-described embodiment, an example in which the lower surface 62b of the second adhesive portion 62 is located above the lower surface 61b of the first adhesive portion 61 has been shown. However, as shown in FIG. 7, the lower surface 61b of the first adhesive portion 61 may be located above the lower surface 62b of the second adhesive portion 62. In FIG. 7, the same reference numerals are given to the same components as those in the above-described embodiment. In FIG. 7, in a plan view, the area of the first gap G1 is larger than the area of the second gap G2. As a result, when the insulating tube 50 is adhered with the adhesive 60x (see FIG. 5B), the amount of the adhesive 60x climbing up is larger in the second gap G2 than in the first gap G1. As a result, it is easy to form the structure of FIG. 7 in which the lower surface 61b of the first adhesive portion 61 is located above the lower surface 62b of the second adhesive portion 62.

[0044] In the above-described embodiment, both the lower surface 61b of the first adhesive portion 61 and the lower surface 62b of the second adhesive portion 62 are located above the bottom surface 32b of the refrigerant flow path 32. However, at least one of the lower surface 61b of the first adhesive portion 61 and the lower surface 62b of the second adhesive portion 6 is located above the bottom surface 32b of the refrigerant flow path 32.

[0045] For example, if the lower surface 62b of the second adhesive portion 62 is at the same height as or above the bottom surface 32b of the refrigerant flow path 32, the lower surface 61b of the first adhesive portion 61 may be at the same height as the bottom surface 32b of the refrigerant flow path 32 or may be below it. An example thereof is shown in FIG. 8. In FIG. 8, the same reference numerals are given to the same components as those in the above-described embodiment. As shown in FIG. 8, if the lower surface 62b of the second adhesive portion 62 is at the same height as or above the bottom surface 32b of the refrigerant flow path 32, the portion of the power supply member 70 below the bottom surface 32b of the refrigerant flow path 32 is not fixed by the first adhesive portion 61 of the adhesive layer 60 and is in a free state. Therefore, even if the portion of the insulating tube 50 below the bottom surface 32b of the refrigerant flow path 32 is fixed by the first adhesive portion 61, the power supply member 70 only deforms in accordance with the deformation above the surface including the bottom surface 32b of the refrigerant flow path 32 of the wafer mounting stage 10. That is, even if the upper part of the wafer mounting stage is at a high temperature and the lower part is at a low temperature and the wafer mounting stage is warped into a convex shape, the power supply member 70 does not change the way of deformation halfway. Therefore, almost no shearing force acts on the connection portion between the power supply member 70 and the electrostatic electrode 22.

[0046] Alternatively, if the lower surface 61b of the first adhesive portion 61 is at the same height as or above the bottom surface 32b of the refrigerant flow path 32, the lower surface 62b of the second adhesive portion 62 may be at the same height as or below the bottom surface 32b of the refrigerant flow path 32. An example of this is shown in Figure 9. In Figure 9, the same reference numerals are used for the same components as in the embodiments described above. As shown in Figure 9, if the lower surface 61b of the first adhesive portion 61 is at the same height as or above the bottom surface 32b of the refrigerant flow path 32, the portion of the insulating tube 50 below the bottom surface 32b of the refrigerant flow path 32 is not fixed by the first adhesive portion 61 and is in a free state. Therefore, even if the portion of the power supply member 70 below the bottom surface 32b of the refrigerant flow path 32 is fixed by the second adhesive portion 62, the insulating tube 50, which is integrated with the power supply member 70 and the second adhesive portion 62, will only deform in accordance with the deformation of the wafer mounting base 10 above the surface including the bottom surface 32b of the refrigerant flow path 32. In other words, even if the wafer mounting table 10 warps into a convex shape due to the upper part becoming hot and the lower part becoming cold, the way in which the insulating tube 50 and the power supply member 70 deform does not change along the way. Therefore, almost no shear force acts on the connection between the power supply member 70 and the electrostatic electrode 22.

[0047] In the above-described embodiment, the shape of the refrigerant flow path 32 was not particularly changed between the peripheral region of the base plate through-hole 34 and the region outside the peripheral region, but it may be changed. For example, in the peripheral region of the base plate through-hole 34, the cross-sectional area of the refrigerant flow path 32 may be made smaller than that in the region outside the peripheral region of the base plate through-hole 34. By doing so, the flow velocity of the refrigerant flowing through the peripheral region of the base plate through-hole 34 in the refrigerant flow path 32 increases. As a result, the heat at the position directly above the base plate through-hole 34 is efficiently transferred to the refrigerant in the refrigerant flow path 32, so that the heat uniformity of the wafer W is improved. When reducing the cross-sectional area of the refrigerant flow path 32, when the cross-section of the refrigerant flow path 32 is rectangular, as shown in FIG. 10, the width (horizontal length) of the refrigerant flow path 32X passing through the peripheral region of the base plate through-hole 34 may be made shorter than the width of the refrigerant flow path 32 passing through the region outside the peripheral region. Alternatively, as shown in FIG. 11, the height (vertical length) of the refrigerant flow path 32X passing through the peripheral region of the base plate through-hole 34 may be made shorter than the height of the refrigerant flow path 32 passing through the region outside the peripheral region. In FIGS. 10 and 11, the same components as those in the above-described embodiment are denoted by the same reference numerals.

[0048] In the above-described embodiment, the height from the ceiling surface of the refrigerant flow path 32 to the wafer placement surface 21 was not particularly changed between the peripheral region of the base plate through-hole 34 and the region outside the peripheral region, but it may be changed. For example, as shown in FIG. 12, the distance from the ceiling surface of the refrigerant flow path 32X passing through the peripheral region of the base plate through-hole 34 in the refrigerant flow path 32 to the wafer placement surface 21 may be made shorter than the distance from the ceiling surface of the refrigerant flow path 32 passing through the region outside the peripheral region to the wafer placement surface 21. As a result, the heat at the position directly above the base plate through-hole 34 is efficiently transferred to the refrigerant in the refrigerant flow path 32, so that the heat uniformity of the wafer W is improved. In FIG. 12, the same components as those in the above-described embodiment are denoted by the same reference numerals.

[0049] In the embodiment described above, both the lower surface 61b of the first adhesive portion 61 and the lower surface 62b of the second adhesive portion 62 are located below the ceiling surface 32a of the refrigerant flow path 32. However, one or both of the lower surfaces 61b of the first adhesive portion 61 and the lower surface 62b of the second adhesive portion 62 may be located above the ceiling surface 32a of the refrigerant flow path 32. However, considering the uniform heating of the wafer W, the embodiment described above is preferable.

[0050] In the embodiment described above, an example was shown in which the lower surface 70b of the power supply member 70 is above the lower surface 50b of the insulating pipe 50, but the embodiment is not limited to this. For example, the lower surface 70b of the power supply member 70 may be at the same height as or below the lower surface 50b of the insulating pipe 50, or at the same height as or below the lower surface of the base plate 30.

[0051] In the embodiment described above, a socket portion 72 is provided on the lower surface 70b of the power supply member 70 and a plug 92 is provided at the end of the external cable 90, but the embodiment is not limited to this. For example, a plug may be provided on the lower surface 70b of the power supply member 70 and a socket may be provided at the end of the external cable 90. Alternatively, the lower surface 70b of the power supply member 70 may be formed in a concave shape, and the end of the external cable 90 may be elastically brought into contact with this lower surface 70b.

[0052] In the embodiments described above, a metal layer was exemplified as the bonding layer 40, but the invention is not limited thereto. For example, a resin layer or an inorganic adhesive may be used as the bonding layer 40. Examples of materials for the resin layer include insulating resins such as epoxy resin, acrylic resin, and silicone resin. The bonding layer 40 may also be an insulating resin containing a filler. The filler preferably has a higher thermal conductivity than the insulating resin of the bonding layer 40, and may be alumina or aluminum nitride, for example. When using a bonding layer with good thermal conductivity, a metal bonding layer is preferable.

[0053] In the embodiment described above, an electrostatic electrode 22 is incorporated into the ceramic plate 20, but the embodiment is not limited thereto. For example, a heater electrode (resistive heating element) or a plasma generating electrode (RF electrode) may be incorporated instead of or in addition to the electrostatic electrode 22.

[0054] This application is based on the priority claim of Japanese Patent Application No. 2024-198269, filed on 13 November 2024, the entire contents of which are incorporated herein by reference.

[0055] This invention can be used in semiconductor manufacturing equipment for processing wafers.

[0056] 10 Wafer mounting stage, 20 Ceramic plate, 21 Wafer mounting surface, 22 Electrostatic electrode, 23 Bottom surface, 24 Ceramic plate with bottom hole, 30 Base plate, 30b Bottom surface, 32 Refrigerant flow path, 32a Top surface, 32b Bottom surface, 32in Inlet, 32out Outlet, 34 Base plate through hole, 40 Bonding layer, 44 Bonding layer through hole, 50 Insulating tube, 50a Top surface, 50b Bottom surface, 54 Insulating tube through hole, 60 Adhesive layer, 60a Top surface, 60x Adhesive, 60X Adhesive, 61 First adhesive part, 61b Bottom surface, 62 Second adhesive part, 62b Bottom surface, 63 Adhesive part, 70 Power supply member, 70a Top surface, 70b Bottom surface, 72 Socket part, 90 External cable, 92 Plug, 910 Wafer mounting platform, 960 adhesive layer, 961 first adhesive portion, 962 second adhesive portion, G1 first gap, G2 second gap, W wafer.

Claims

1. A semiconductor manufacturing apparatus component comprising: a ceramic plate having a wafer mounting surface on its upper surface and containing electrodes; a base plate provided on the lower surface of the ceramic plate and containing a refrigerant flow path; a base plate through-hole extending vertically through the base plate at a position off-center from the base plate; an insulating tube inserted into the base plate through-hole; a power supply member inserted into the insulating tube and having its tip electrically connected to the electrodes; and an adhesive layer having a first adhesive portion provided in a first gap between the insulating tube and the base plate through-hole and a second adhesive portion provided in a second gap between the insulating tube and the power supply member, wherein the lower surface of the power supply member is below the bottom surface of the refrigerant flow path, and at least one of the lower surfaces of the first adhesive portion and the second adhesive portion is at the same height as or above the bottom surface of the refrigerant flow path.

2. The absolute value of the difference in thermal expansion coefficients between the ceramic plate and the base plate at 40 to 570°C is 1.0 ppm / K or less, the semiconductor manufacturing apparatus component according to claim 1.

3. The semiconductor manufacturing apparatus component according to claim 1 or 2, wherein both the lower surface of the first adhesive portion and the lower surface of the second adhesive portion are at the same height as or below the ceiling surface of the refrigerant flow path.

4. The semiconductor manufacturing apparatus component according to claim 1 or 2, wherein both the lower surface of the first adhesive portion and the lower surface of the second adhesive portion are at the same height as or above the bottom surface of the refrigerant flow path.

5. In a plan view, the area of ​​the first gap is smaller than the area of ​​the second gap, the semiconductor manufacturing apparatus component according to claim 1 or 2.

6. The lower surface of the power supply member is provided with a connector that can be connected to the tip of an external cable and is located above the lower surface of the insulating tube, and the lower surface of the second adhesive portion is located above the lower surface of the power supply member, as described in claim 1 or 2.

7. The thermal conductivity of the base plate is 50 W / mK or higher, as described in claim 1 or 2, for semiconductor manufacturing apparatus components.

8. The thermal conductivity of the first and second adhesive portions is 0.5 W / mK or higher, the semiconductor manufacturing apparatus component according to claim 1 or 2.

9. The cross-sectional area of ​​the refrigerant flow path is smaller in the region surrounding the base plate through-hole than in the region outside the region surrounding the base plate through-hole, according to claim 1 or 2.

10. The distance from the wafer mounting surface to the ceiling surface of the refrigerant flow path is shorter in the region surrounding the base plate through-hole than in the region outside the region surrounding the base plate through-hole, as described in claim 1 or 2.

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