Temperature control device and wafer processing system

Abstract

To provide a temperature control device and a wafer processing system in which deformation of a top plate is further suppressed.SOLUTION: A temperature control device comprises: a top plate that forms a disk shape with an axis as a center, and has an arrangement surface where an object is arranged; a Peltier member that is arranged by contacting the top plate from an axial direction; a cooling plate that contacts the Peltier member so as to be arranged on the side opposite to the top plate in the axial direction to the Peltier member, and in which a coolant circulates in the inside; a cover plate that forms a housing space for housing the Peltier member and the cooling plate between itself and the top plate; and a pressure reduction device that reduces a pressure in the housing space. The top plate and the cooling plate do not come into contact with each other.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a temperature adjustment apparatus and a wafer processing system. [Background technology]

[0002] In semiconductor manufacturing equipment, a temperature control device is used to control the temperature of a wafer. A specific example of this type of device is described in Patent Document 1 below. The device according to Patent Document 1 below mainly comprises a circular top plate, a plurality of Peltier modules stacked under the top plate, and a cooling plate that supports the Peltier modules from below and controls the temperature. A refrigerant flows inside the cooling plate. An airtight space is formed between the cooling plate and the top plate, and the Peltier module is housed in the space.

[0003] Here, the above-mentioned temperature control device may be used in a vacuum chamber. In that case, the pressure in the space housing the above-mentioned Peltier module becomes relatively high compared to the surrounding pressure, and the pressure difference causes deformation of the top plate. Therefore, the device is configured to suck air from within the space to reduce the pressure difference with the surroundings. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2022-18881 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the cooling plate itself may deform due to the heat of the Peltier module or the pressure difference, so when a space is formed by joining the top plate and the cooling plate as described above, the top plate may still be affected, causing deformation or distortion.

[0006] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a temperature control apparatus and a wafer processing system in which deformation of the top plate is further suppressed. [Means for solving the problem]

[0007] In order to solve the above problems, the temperature adjustment device of the present invention includes a top plate which is disk-shaped about an axis and has a placement surface on which an object is placed, a Peltier member arranged in contact with the top plate from the axial direction, a cooling plate which is arranged on the opposite side of the Peltier member from the top plate in the axial direction and in contact with the Peltier member and through which a refrigerant flows, a cover plate which forms an accommodation space between the top plate and the cover plate to accommodate the Peltier member and the cooling plate, and a pressure reducing device which reduces pressure in the accommodation space, wherein the top plate and the cooling plate are not in contact with each other.

[0008] A wafer processing system according to the present invention includes the above-mentioned temperature adjustment device and a chamber having a low-pressure space for accommodating the temperature adjustment device. Effect of the Invention

[0009] According to the present invention, it is possible to provide a temperature adjustment apparatus and a wafer processing system in which deformation of the top plate is further suppressed. [Brief description of the drawings]

[0010] [Figure 1] 1 is an overall view showing a configuration of a wafer processing system according to an embodiment of the present invention; [Diagram 2] 1 is a cross-sectional view showing a configuration of a temperature control device according to an embodiment of the present invention. [Diagram 3] FIG. 4 is an enlarged cross-sectional view of a main portion showing a modified example of a temperature control device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] (Configuration of wafer processing system 1) Hereinafter, a wafer processing system 1 and a temperature adjustment device 2 according to an embodiment of the present invention will be described with reference to FIGS.

[0012] The wafer processing system 1 is an apparatus for supporting a silicon wafer (wafer 100) used in semiconductor manufacturing as an object and performing various processes on the wafer 100. As shown in FIG.

[0013] The chamber 10 is a housing with a space formed therein, and the interior is evacuated to form a low-pressure space 11. The pressure of this low-pressure space 11 is preferably 1 Pa or more and 250 Pa or less. More preferably, the pressure of the low-pressure space 11 is 1.5 Pa or more and 230 Pa or less. Most preferably, the pressure of the low-pressure space 11 is 2 Pa or more and 220 Pa or less.

[0014] The chamber 10 is provided with an exhaust pipe 12 for discharging air to the outside. Air in the low pressure space 11 is sucked to the outside through this exhaust pipe 52, and the above-mentioned pressure state is realized. Depending on the type of process performed on the wafer 100, it is not always necessary to reduce the pressure, and the pressure in the chamber 10 may be equivalent to atmospheric pressure. A gas supply device 13 is disposed on the top surface (inner surface facing downward) of the chamber 10. This gas supply device 13 supplies a gas containing a rare gas element such as argon or xenon into the chamber 10.

[0015] (Configuration of temperature control device 2) The temperature control device 2 is disposed on the bottom surface of the chamber 10. The temperature control device 2 is a device for controlling the temperature of the wafer 100. The temperature control device 2 includes a top plate 20, a Peltier member 21, a cooling plate 22, a cover plate 23, a power supply device 24, a cooling water supply device 25, and a vacuum generating device 26 (pressure reducing device).

[0016] The top plate 20 has an arrangement surface 30 on which the wafer 100 is arranged. The arrangement surface 30 faces upward. As shown in FIG. 2, the top plate 20 has a disk shape centered on the axis X. As shown in FIG. 1 again, a Peltier member 21 is provided below the top plate 20. The Peltier member 21 is connected to a power supply device 24. The Peltier member 21 is a collection of circuit elements (Peltier elements) that can generate or absorb heat by receiving a current from the power supply device 24. A cooling plate 22 is provided further below the Peltier member 21. That is, the cooling plate 22 is provided on the opposite side of the top plate 20 with respect to the Peltier member 21. The cooling plate 22 is a member for controlling the temperature of the Peltier member 21 more precisely. A flow path 22a is formed in the cooling plate 22, through which the cooling water (coolant) supplied and discharged from the cooling water supply device 25 flows (see FIG. 2).

[0017] The Peltier member 21 and the cooling plate 22 are accommodated in an accommodation space V formed by a top plate 20 and a cover plate 23. In other words, the cover plate 23 covers the Peltier member 21 and the cooling plate 22 from below. As will be described in detail later, the cover plate 23 is joined to the top plate 20, and the accommodation space V is kept airtight. In order to reduce the pressure in the accommodation space V, a vacuum generator 26 is provided. The vacuum generator 26 is, for example, an ejector, and receives a supply of air from the outside, and guides the air in the accommodation space V to the outside along with the flow of the air. This reduces the pressure in the accommodation space V. As an example, the pressure in the accommodation space V is preferably 3 kPa or more and 30 kPa or less. More preferably, the pressure is 5 kPa or more and 27 kPa or less. Most preferably, the pressure is 7 kPa or more and 25 kPa or less.

[0018] Next, the detailed configuration of the temperature control device 2 will be described with reference to Fig. 2. As shown in the figure, the top plate 20 has a disk-shaped plate body 20a and a flange portion 20b that protrudes from the outer periphery of the plate body 20a. The cover plate 23 has a cover plate body 23a that forms the lower part of the accommodation space V and an opposing flange portion 23b that protrudes from the cover plate body 23a to the outer periphery.

[0019] The flange portion 20b is fastened and fixed by bolts 27 in a state facing the opposing flange portion 23b in the direction of the axis X. In addition, an O-ring serving as a seal member 28 is sandwiched between the flange portion 20b and the opposing flange portion 23b. This ensures airtightness between the accommodation space V and the outside. In addition, since the cover plate 23 is provided, the top plate 20 and the cooling plate 22 do not abut against each other and are not in contact with each other when forming the accommodation space V.

[0020] Additionally, the top plate 20 and the cover plate 23 are fastened to each other at the position of the axis X by a center bolt (bolt) 70. The center bolt 70 is screwed from the cover plate 23 side toward the top plate 20. A heat insulating member 31 is provided at a portion of the cover plate 23 that comes into contact with the center bolt 70. The heat insulating member 31 is preferably made of a resin such as rubber, or a porous body.

[0021] Further, the cover plate 23 is provided with a supply section 40 and a discharge section 50 for supplying and discharging cooling water to and from the flow passage 22a of the cooling plate 22. The supply section 40 has a cylindrical first bracket 41 inserted into an opening provided in the lower part of the cover plate 23, a supply pipe 42 supported by the first bracket 41, and a seal member 28 for filling gaps between the respective parts. The first bracket 41 has a cylindrical main body section 43 and a protruding section 44 protruding from one end of the main body section 43 to the outer periphery. The protruding section 44 is exposed to the outside of the cover plate 23. A seal member 28 is provided between the supply pipe 42 and the bracket, and between the bracket (protruding section 44) and the bottom surface of the cover plate 23. Similarly, the discharge section 50 has a second bracket 51, a discharge pipe 52, and a seal member 28. The position where the seal member 28 is provided is the same as that of the supply section 40. In addition, an exhaust passage 60 connected to a vacuum generator 26 is provided at the bottom of the cover plate 23 .

[0022] When using the temperature adjustment device 2, first, cooling water is supplied to and drained from the cooling plate 22, and an electric current is supplied to the Peltier member 21 to generate heat or cool it. In this state, the wafer 100 is placed on the placement surface 30 of the top plate 20, and various processes such as cleaning, etching, and deposition are performed on the wafer 100. At this time, the temperature adjustment device 2 makes it possible to maintain the temperature of the wafer 100 uniform and constant.

[0023] However, the cooling plate 22 itself may deform due to the heat of the Peltier module or the pressure difference between the surroundings and the accommodation space V. For this reason, when the accommodation space V is formed by joining the top plate 20 and the cooling plate 22 as in the past, the top plate 20 may still be affected, causing deformation or distortion. This may impair the flatness of the top plate 20, affecting the processing of the wafer 100. Therefore, the above-mentioned configurations are adopted in this embodiment.

[0024] <Effects> The temperature control device 2 of the above-described embodiment can achieve the following effects. In this embodiment, an accommodation space V is formed inside by joining the top plate 20 and the cover plate 23, and the top plate 20 and the cooling plate 22 are not in contact with each other.

[0025] As a result, even if the cooling plate 22 is deformed due to heat or a pressure difference, the stress caused by the deformation does not reach the top plate 20. This reduces the possibility that the top plate 20 is deformed or distorted, and makes it possible to maintain a high degree of flatness.

[0026] In this embodiment, a seal member 28 for ensuring airtightness between the top plate 20 and the cover plate 23 is further provided.

[0027] This ensures airtightness within the accommodation space V defined by the top plate 20 and the cover plate 23. Therefore, the pressure within the accommodation space V can be stably reduced by the pressure reducing device.

[0028] In this embodiment, the top plate 20 has a flange portion 20b that protrudes outward more than the Peltier member 21 and the cooling plate 22 when viewed in the direction of the axis X, and the cover plate 23 has an opposing flange portion 23b that faces the flange portion 20b and sandwiches the seal member 28.

[0029] By connecting the top plate 20 and the cover plate 23 with the flange portion 20b and the opposing flange portion 23b, the area of ​​the placement surface 30 of the top plate 20 is not eroded. Also, by simply fastening the flange portion 20b and the opposing flange portion 23b with bolts 27 or the like, it is possible to easily and stably ensure an airtight state within the accommodation space V. This makes it possible to significantly reduce the manufacturing costs and maintenance costs of the device.

[0030] In this embodiment, a center bolt 70 that fastens the top plate 20 and the cooling plate 22 in the direction of the axis X, and a heat insulating member 31 arranged on the portion of the cooling plate 22 that contacts the center bolt 70 are further provided.

[0031] The top plate 20 and the cooling plate 22 need to be fastened and fixed from both sides in the thickness direction (axis X direction) in order to sandwich the Peltier member 21 therebetween. For this purpose, the center bolt 70 is used. However, if the top plate 20 and the cooling plate 22 are thermally connected by the center bolt 70, heat transfer occurs between them, and the temperature uniformity of the top plate 20 is impaired. Therefore, as described above, the heat insulating member 31 is provided at the portion of the cooling plate 22 that contacts the center bolt 70. This thermally insulates the center bolt 70 and the cooling plate 22, and the above-mentioned heat transfer does not occur. Therefore, it is possible to further improve the temperature uniformity of the top plate 20.

[0032] In this embodiment, the dimension of the top plate 20 in the direction of the axis X is not less than 0.1 mm and not more than 5 mm.

[0033] As described above, the pressure inside the accommodation space V is lowered and the pressure difference with the surroundings is reduced, so that the top plate 20 is less likely to deform due to the pressure difference. Therefore, the thickness of the top plate 20 (the dimension in the direction of the axis X) can be kept within a small range of 0.1 mm to 5 mm. As a result, the responsiveness of temperature adjustment by the transfer of heat from the Peltier member 21 to the top plate 20 is improved, and various production processes can be carried out more efficiently and stably.

[0034] In this embodiment, at least one of the top plate 20 and the cover plate 23 is made of one material selected from the group including aluminum, an aluminum alloy, stainless steel, copper, a copper alloy, and ceramics.

[0035] This makes it possible to ensure high levels of rigidity, heat transferability, and manufacturing costs for the top plate 20 and the cover plate 23. Therefore, it becomes possible to achieve a high level of balance between performance and cost of the temperature adjustment device 2.

[0036] Although the embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like that do not deviate from the gist of the present invention are also included.

[0037] For example, as shown as a modified example in FIG. 3, the top plate 20 may cover the Peltier member 21 and the cooling plate 22 from the outer circumferential side and have a cylindrical portion 20c centered on the axis X, and the cover plate 23 may have a cylindrical opposing cylindrical portion 23c that faces the cylindrical portion 20c in the radial direction and sandwiches the sealing member 28.

[0038] According to this configuration, the same effect (sealing effect) as the above-mentioned configuration can be obtained. In addition, since the cylindrical portion 20c and the opposing cylindrical portion 23c are opposed to each other in the radial direction and sandwich the seal member 28, even if the top plate 20 thermally expands in the radial direction, the cylindrical portion 20c is strongly pressed against the opposing cylindrical portion 23c. This makes it possible to ensure even greater airtightness. On the other hand, if the dimensions and hardness of the seal member 28 are adjusted, it becomes possible to absorb the thermal expansion and deformation of the top plate 20 by the deformation of the seal member 28. This makes it possible to further improve the performance of the temperature adjustment device 2.

[0039] In the above embodiment, the Peltier member 21 is described as having a uniform disk shape, but the shape of the Peltier member 21 is not limited to this. As another example, it is also possible to adopt a configuration in which a plurality of Peltier elements are arranged on a plane at intervals. However, in terms of preventing temperature unevenness of the top plate 20, a configuration having a uniform disk shape is more advantageous.

[0040] Furthermore, the temperature control device 2 can be used in various work processes even outside the above-mentioned chamber 10. Even in this case, the same effects as those described above can be obtained.

[0041] The number of seal members 28 in each of the above-mentioned parts is merely an example, and can be changed as appropriate according to the design and specifications. In any case, the same effects as those described above can be obtained. [Explanation of symbols]

[0042] 1...wafer processing system 2...temperature control device 10...chamber 11...low pressure space 12...exhaust pipe 13...gas supply device 20...top plate 20a...plate body 20b...flange portion 20c...cylindrical portion 21...peltier member 22...cooling plate 22a...flow path 23...cover plate 23a...cover plate body 23b...facing flange portion 23c...facing cylindrical portion 24...power supply device 25...cooling water supply device 26...vacuum generator 27...bolt 28...sealing member 30...arrangement surface 31...insulating member 40...supply portion 41...first bracket 42...supply pipe 43...main body portion 44...extension portion 50...exhaust portion 51...second bracket 52...exhaust pipe 60...exhaust flow path 70...center bolt 100...wafer X...axis V...accommodation space

Claims

1. A top plate having a disk shape centered on an axis and having a placement surface on which an object is placed; a Peltier member disposed in contact with the top plate in the axial direction; a cooling plate that is disposed on the Peltier member on the opposite side to the top plate in the axial direction and is in contact with the Peltier member, and through which a refrigerant flows; a cover plate that defines an accommodation space between the cover plate and the top plate to accommodate the Peltier member and the cooling plate; A pressure reducing device for reducing the pressure in the storage space; Equipped with The temperature control device, wherein the top plate and the cooling plate are not in contact with each other.

2. The temperature control device according to claim 1 , further comprising a seal member for ensuring airtightness between the top plate and the cover plate.

3. the top plate has a flange portion that protrudes outward more radially than the Peltier member and the cooling plate when viewed in the axial direction, The temperature control device according to claim 2 , wherein the cover plate has an opposing flange portion that faces the flange portion and holds the seal member therebetween.

4. the top plate covers the Peltier member and the cooling plate from an outer circumferential side and has a cylindrical portion having a cylindrical shape centered on the axis line, The temperature control device according to claim 2 , wherein the cover plate has a cylindrical opposing portion that faces the cylindrical portion in a radial direction and that holds the seal member therebetween.

5. a bolt that fastens the top plate and the cooling plate in the axial direction; A heat insulating member disposed in a portion of the cooling plate in contact with the bolt; The temperature control device according to claim 1 , further comprising:

6. 2. The temperature control device according to claim 1, wherein a dimension of the top plate in the axial direction is not less than 0.1 mm and not more than 5 mm.

7. 2. The temperature control device according to claim 1, wherein at least one of the top plate and the cover plate is made of a material selected from the group consisting of aluminum, aluminum alloy, stainless steel, copper, copper alloy, and ceramics.

8. The temperature control device according to claim 1 ; a chamber having a low pressure space for accommodating the temperature control device; A wafer processing system comprising:

9. 9. The wafer processing system according to claim 8, wherein the pressure in the low pressure space is 1 Pa or more and 250 Pa or less, and the pressure in the accommodation space is 0.3 kPa or more and 30 kPa or less.

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