Holding device

Abstract

A technology for improving thermal uniformity in a holding device is provided. [Solution] The holding device comprises a plurality of flow path forming members that form a flow path through which the refrigerant flows, and a joint that joins the plurality of flow path forming members to each other, and a gap that communicates with the flow path is formed between the flow path forming members and the joint.

Description

[Technical Field]

[0001] The present invention relates to a retaining device. [Background technology]

[0002] BACKGROUND ART Conventionally, there have been known holding devices that have a flow path through which a refrigerant flows and that hold an object (for example, Patent Documents 1 to 4). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-70860 [Patent Document 2] Japanese Patent Publication No. 2023-70861 [Patent Document 3] Japanese Patent Application Publication No. 2019-207969 [Patent Document 4] Japanese Patent Application Laid-Open No. 2016-012733 Summary of the Invention [Problem to be solved by the invention]

[0004] However, even with the prior art such as Patent Documents 1 to 4, there is still room for improvement in the technology for improving the temperature uniformity in the holding device.

[0005] An object of the present invention is to provide a technique for improving the temperature uniformity in a holding device. [Means for solving the problem]

[0006] The present invention has been made to solve at least part of the above-mentioned problems, and can be realized in the following aspects.

[0007] (1) According to one aspect of the present invention, there is provided a holding device for holding an object, the holding device including a plurality of flow path forming members that form a flow path through which a refrigerant flows, and a joint that joins the plurality of flow path forming members to each other, and a gap that communicates with the flow path is formed between the flow path forming members and the joint.

[0008] According to this configuration, the gap formed between the flow path forming member and the joint portion communicates with the flow path, allowing the refrigerant flowing through the flow path to flow in and out. This allows the refrigerant to spread over a wider area inside the holding device than the area occupied by the flow path, thereby improving the thermal uniformity of the holding device.

[0009] (2) The holding device of the above embodiment may further have a mounting surface on which the object is placed, and each of the plurality of flow path forming members may have a plate shape having a pair of main surfaces, and may be arranged so that each of the pair of main surfaces is parallel to the mounting surface, the joint portion may be in contact with at least one of the pair of main surfaces of the flow path forming member, and the plurality of flow path forming members and the joint portion may be stacked. According to this configuration, the flow path forming member having a pair of main surfaces is arranged so as to be parallel to the mounting surface, and the joint portion is in contact with one of the pair of main surfaces of the flow path forming member. As a result, a gap through which the refrigerant flows in and out is formed along a direction parallel to the mounting surface, thereby improving thermal uniformity on the mounting surface.

[0010] (3) In the holding device of the above aspect, in a cross section including a central axis of the holding device and including a plurality of cross sections of the flow channels, the holding device may have a first specific region as a specific region including a region between the flow channel-forming member and the junction, and a second specific region located between the first specific region and a specific flow channel among the plurality of flow channels that is closest to the first specific region, wherein the length of a portion of the second specific region where the flow channel-forming member contacts the junction is shorter than the length of a portion of the first specific region where the flow channel-forming member contacts the junction. According to this configuration, in a cross section including a central axis of the holding device and including a plurality of cross sections of the flow channels, when a first specific region including a region between the flow channel-forming member and the junction and a second specific region closer to the specific flow channel than the first specific flow region are set, the length of the portion of the second specific region where the flow channel-forming member contacts the junction is shorter than the length of the portion of the first specific region where the flow channel-forming member contacts the junction. That is, in the second specific region, which is relatively close to the specific flow path, there are relatively many gaps, i.e., areas where the flow path forming member and the joint are not in contact, so the area over which the refrigerant can circulate is wider, while in the first specific region, which is relatively far from the specific flow path, the area over which the flow path forming member and the joint are in contact is longer, so that multiple flow path forming members can be reliably joined via the joint.

[0011] (4) In the holding device of the above aspect, the length of the portion where the flow path forming member and the joint included in the specific region contact each other may become shorter as the center of the specific region approaches the specific flow path. According to this configuration, the gap is formed so that the length of the portion where the flow path forming member and the joint contact each other becomes shorter as the center of the specific region approaches the specific flow path. This makes it possible to increase the bonding force of the flow path forming member via the joint while widening the range over which the refrigerant is distributed.

[0012] (5) In the holding device of the above aspect, the end of the joint on the flow path side may be formed to protrude. With this configuration, the end of the joint on the flow path side is formed to protrude, which makes it easier for the flow of the refrigerant flowing through the flow path to become turbulent. In other words, the flow of the refrigerant is more likely to become turbulent, which promotes heat exchange between the flow path forming member or the joint and the refrigerant. This can improve the cooling efficiency of the refrigerant.

[0013] (6) In the holding device of the above aspect, the joint may be formed of a metal. According to this configuration, the joint is formed of a metal having a relatively high thermal conductivity. This makes it easier for the cold heat of the refrigerant to be transferred to the flow path forming member via the joint, thereby improving the cooling performance of the holding device.

[0014] The present invention can be realized in various forms, for example, in the form of a method for manufacturing a holding device, a system including a holding device, a control method for a holding device and a system including a holding device, a computer program for executing the manufacture of a holding device and a system including a holding device, etc. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 2 is a perspective view of the holding device of the first embodiment. [Figure 2] FIG. 2 is a cross-sectional view of the holding device of the first embodiment. [Figure 3] FIG. 3 is an enlarged view of part A in FIG. 2. [Figure 4] FIG. 2 is a first diagram illustrating the features of the holding device of the first embodiment. [Figure 5] FIG. 4 is a second diagram illustrating the features of the holding device of the first embodiment. [Figure 6] FIG. 10 is a third diagram illustrating the features of the holding device of the first embodiment. [Figure 7] FIG. 4 is a fourth diagram illustrating the features of the holding device of the first embodiment. [Figure 8] 5A to 5C are diagrams illustrating the effect of the holding device of the first embodiment. [Figure 9] FIG. 10 is a cross-sectional view of a holding device according to a second embodiment. [Figure 10] FIG. 10 is a cross-sectional view of a holding device according to a third embodiment. [Figure 11] FIG. 10 is a cross-sectional view of a holding device according to a fourth embodiment. [Figure 12] FIG. 10 is a cross-sectional view of a holding device according to a fifth embodiment. [Figure 13] FIG. 10 is a cross-sectional view of a holding device according to a sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0016] First Embodiment FIG. 1 is a perspective view of a holding device 1 according to a first embodiment. FIG. 2 is a cross-sectional view of the holding device 1 according to the first embodiment, showing a cross section including a central axis C1 of the holding device 1. The holding device 1 according to the first embodiment is a so-called electrostatic chuck that is installed in, for example, an etching device and holds a wafer W by electrostatic attraction. The holding device 1 includes a first member 10, a second member 20, and a bonding layer 30. As shown in FIG. 1, the holding device 1 is stacked in the following order from the negative side in the z-axis direction (stacking direction). In this embodiment, the holding device 1 is a columnar body having a substantially circular cross-sectional shape perpendicular to the stacking direction. Note that FIGS. 1 and 2 schematically show the arrangement of each part and do not accurately represent the dimensional ratios of each part.

[0017] The first member 10 is a substantially circular member made mainly of silicon carbide (SiC). A flow path 100 is formed inside the first member 10, through which a coolant such as a fluorine-based inert liquid or water flows. The first member 10 functions as a cooling section in the holding device 1. The detailed configuration of the first member 10 will be described later.

[0018] The second member 20 is a substantially circular, flat member made of alumina (Al2O3). The second member 20 functions as a holder for holding the wafer W in the holding device 1. The second member 20 has a mounting surface 20a on which the wafer W is mounted. The wafer W mounted on the mounting surface 20a is attracted and fixed to the mounting surface 20a by electrostatic attraction generated by a chuck electrode 21 disposed inside the second member 20. In this embodiment, a heater electrode 22 for heating the wafer W attracted and fixed to the mounting surface 20a is built into the second member 20. The second member 20 may be made of aluminum nitride (AlN), silicon carbide, or the like. In addition to the chuck electrode 21 and the heater electrode 22, a high-frequency electrode may be built into the second member 20.

[0019] The bonding layer 30 is disposed between the first member 10 and the second member 20, and bonds the first member 10 and the second member 20 together. The bonding layer 30 is a brazing material containing aluminum (Al). The bonding layer 30 of this embodiment has a generally circular disk shape with an outer diameter the same as that of the second member 20. Holes (tunnels) (not shown) are formed in the bonding layer 30 along the stacking direction of the holding device 1. Terminals for supplying electricity to the chuck electrode 21, lift pins (not shown) used to detach the wafer W from the mounting surface 20a, etc. are inserted through the holes formed in the bonding layer 30.

[0020] Next, features of the holding device 1 of this embodiment will be described. The first member 10 included in the holding device 1 includes a plurality of flow path forming members 11, 12, and 13 that form a flow path 100 through which a refrigerant flows, and joints 14 and 15 that join the plurality of flow path forming members 11, 12, and 13. In the first member 10, the plurality of flow path forming members 11, 12, and 13 and the joints 14 and 15 are stacked. Specifically, as shown in FIG. 2, in the first member 10, the flow path forming member 11, the joint 14, the flow path forming member 12, the joint 15, and the flow path forming member 13 are stacked in this order from the positive side in the z-axis direction.

[0021] Each of the multiple flow path forming members 11, 12, and 13 is made of silicon carbide. The flow path forming member 11 has a plate shape with a pair of main surfaces 11a and 11b, and is disposed so that each of the pair of main surfaces 11a and 11b is parallel to the mounting surface 20a. The flow path forming member 12 has a plate shape with a pair of main surfaces 12a and 12b, and is disposed so that each of the pair of main surfaces 12a and 12b is parallel to the mounting surface 20a. The flow path forming member 13 has a plate shape with a pair of main surfaces 13a and 13b, and is disposed so that each of the pair of main surfaces 13a and 13b is parallel to the mounting surface 20a. The flow path forming member 12 is sandwiched between the flow path forming member 11 and the flow path forming member 13, and has a space 12c that becomes the flow path 100. The space 12c is open to each of the pair of main surfaces 12a and 12b. The material forming each of the flow path forming members 11, 12, and 13 may be aluminum, titanium (Ti), molybdenum (Mo), an alloy containing these metals, SUS, alumina, aluminum nitride, metal ceramic composite materials (MMC, Metal Matrix Composites) such as Al / SiC and Ti / SiC, etc.

[0022] The joints 14 and 15 are made of metal. In this embodiment, the joints 14 and 15 are made of aluminum. The joint 14 is disposed between the flow path forming member 11 and the flow path forming member 12. The joint 15 is disposed between the flow path forming member 12 and the flow path forming member 13. The joints 14 and 15 may be formed of a resin material such as silicone or epoxy, titanium, or the like.

[0023] The joint 14 is in contact with the other main surface 11b of the pair of main surfaces 11a, 11b of the flow path forming member 11, and is in contact with one main surface 12a of the pair of main surfaces 12a, 12b of the flow path forming member 12. The joint 14 joins the flow path forming member 11 and the flow path forming member 12 to each other. The joint 15 is in contact with the other main surface 12b of the pair of main surfaces 12a, 12b of the flow path forming member 12, and is in contact with one main surface 13a of the pair of main surfaces 13a, 13b of the flow path forming member 13. The joint 15 joins the flow path forming member 12 and the flow path forming member 13 to each other.

[0024] FIG. 3 is an enlarged view of portion A in FIG. 2. FIG. 3 is a schematic diagram showing an enlarged view of a portion of the cross-sectional view of the holding device 1 shown in FIG. 2 where the flow path forming members 11 and 12 are joined by the joint 14. In the holding device 1 of this embodiment, a gap 110 communicating with the flow path 100 is formed between the flow path forming members 11 and 12 and the joint 14. In FIG. 3, the gap 110, which is not visible in the cross-section shown in FIG. 3, is shown by a dotted line. This allows the refrigerant flowing through the flow path 100 to enter and exit the gap 110. Note that while FIG. 3 shows the gap 110 formed between the flow path forming members 11 and 12 and the joint 14, a gap 110 communicating with the flow path 100 is also formed between the flow path forming members 12 and 13 and the joint 15.

[0025] Here, a method for determining whether the gaps 110 formed between the flow path forming members 11, 12, and 13 and the joints 14 and 15 in the holding device 1 are in communication with the flow path 100 will be described. A cutaway model including the central axis C1 is prepared for the holding device 1. Specifically, the holding device 1 is prepared in a state in which the cross section shown in FIG. 2 is visible. The spread of the liquid when flowing through the flow path 100 of the prepared cutaway model is observed. When the gaps 110 are in communication with the flow path 100, the liquid seeps from the flow path 100 into the gaps 110, resulting in a flow range that is wider than the flow path 100. When the gaps 110 are not in communication with the flow path 100 or when no gaps 110 are formed, the flow range of the liquid is the same as the flow path 100. In this way, by observing the spread of the liquid flowing through the flow path 100, it is possible to determine whether the gaps 110 are in communication with the flow path 100. The method for determining whether the gap 110 is in communication with the flow path 100 is not limited to this.

[0026] In the holding device 1 of this embodiment, the gap 110 is formed within a distance of 0.1 mm to 3 mm from the end of the joints 14, 15 on the flow path 100 side. Specifically, in the cross section of the first member 10 shown in FIG. 3 , if a position P11 is a position 0.1 mm away from the end 14a of the joint 14 in the negative y-axis direction, and a position P12 is a position 3 mm away from the end 14a of the joint 14 in the negative y-axis direction, the gap 110 in the holding device 1 of this embodiment is formed within a range R1 between the positions P11 and P12 shown in FIG. 3 . Forming the gap 110 within the range R1 improves the thermal uniformity of the holding device 1 while ensuring a certain level of bonding strength between the flow path forming member 11 and the joints 14. The same range in which the gap 110 is formed applies to the relationship between the flow path forming member 12 and the joints 14 and between the flow path forming members 12, 13 and the joints 15. In this embodiment, the "distance from the end of the joint on the flow path side" is not limited to the distance on the negative y-axis, but may be any "distance" in the direction away from the flow path on a horizontal plane including the x-axis and y-axis.

[0027] In the holding device 1 of this embodiment, an end 14a of the joint 14 on the flow path 100 side is formed to protrude toward the flow path 100. As shown in FIG. 3 , the end 14a of the joint 14 on the flow path 100 side is located between the other main surface 11b of the flow path forming member 11 and one main surface 12a of the flow path forming member 12. The refrigerant flowing through the flow path 100 flows in and out of the gap 110 through the gap between the other main surface 11b of the flow path forming member 11 and one main surface 12a of the flow path forming member 12.

[0028] FIG. 4 is a first diagram illustrating features of the holding device 1 of this embodiment. FIG. 5 is a second diagram illustrating features of the holding device 1 of this embodiment. FIGS. 4 and 5 are cross-sectional SEM photographs of the holding device 1. FIGS. 4 and 5 show a portion where the flow path forming member 11 and the flow path forming member 12 of the first member 10 are joined by the joint 14. FIG. 5 is a cross-sectional SEM photograph enlarging a portion of portion B of the cross-sectional SEM photograph shown in FIG. 4. From the cross-sectional SEM photograph of FIG. 4, it can be seen that gaps 110 are formed between the flow path forming member 11 and the joint 14 and between the flow path forming member 12 and the joint 14. In FIG. 5, the gaps 110 that are not visible in the cross-sectional SEM photograph are indicated by dashed lines. The gaps 110 visible in the cross-sectional SEM photograph of FIG. 5 are connected to the flow path 100 via the gaps 110 indicated by the dashed lines. 4 and 5, a hollow arrow D100 is shown indicating the direction in which the flow channel 100 is formed relative to the gap 110.

[0029] FIG. 6 is a third diagram illustrating features of the holding device 1 of this embodiment. FIG. 6 is a cross-section including the central axis C1 of the holding device 1 and including multiple cross-sections of the flow paths 100. Specifically, FIG. 6 is a schematic cross-sectional view of a portion where the flow path forming member 11 and the flow path forming member 12 are joined by the joint 14. In the cross-section including the central axis C1 of the holding device 1, the first member 10 of this embodiment has a first specific region SR1 as a specific region including the portion between the flow path forming member 11 and the joint 14, and a second specific region SR2 located between the first specific region SR1 and a specific flow path 100S of the multiple flow paths 100 that is closest to the first specific region SR1. In this case, the length of the portion of the second specific region SR2 where the flow path forming member 11 and the joint 14 contact each other is shorter than the length of the portion of the first specific region SR1 where the flow path forming member 11 and the joint 14 contact each other.

[0030] The relationship between the first specific region SR1 and the second specific region SR2 described above will now be described with reference to FIG. 6. In FIG. 6, a first specific region SR1 is defined that includes the region between the flow path forming member 11 and the joint 14. Next, a specific flow path 100S is defined that is closest to the first specific region SR1 among the multiple flow paths 100 (in FIG. 6, this corresponds to the flow path 100 located on the left side of the flow path forming member 12). Next, in FIG. 6, a second specific region SR2 is defined that is located between the specific flow path 100S and the first specific region SR1. Comparing the lengths of the contact portions between the flow path forming member 11 and the joint 14 for the first specific region SR1 and the second specific region SR2 defined in this manner, the length of the contact portion between the flow path forming member 11 and the joint 14 included in the second specific region SR2 is shorter than the length of the contact portion between the flow path forming member 11 and the joint 14 included in the first specific region SR1. That is, the length of the gap 110 included in the second specific region SR2 is longer than the length of the gap 110 included in the first specific region SR1. This relationship of the length of the contact portion between the flow path forming member 11 and the joint 14 is also true between the flow path forming member 12 and the joint 14, between the flow path forming member 12 and the joint 15, and between the flow path forming member 13 and the joint 15. Note that, since FIG. 6 is described using a cross section perpendicular to the x-axis, the length of the contact portion between the flow path forming member 11 and the joint 14 is the length in the y-axis direction, but the length of the contact portion between the flow path forming members 11, 12, and 13 and the joints 14 and 15 may be the "length" in a horizontal plane including the x-axis and y-axis.

[0031] 6, in the first member 10 of this embodiment, the lengths of the portions where the flow path forming members 11 and the joints 14 included in the multiple specific regions SR1, SR2, SR3, and SR4 are in contact with each other become shorter as the centers CS11, CS12, CS13, and CS14 of the multiple specific regions SR1, SR2, SR3, and SR4, respectively, become closer to the specific flow path 100S. Specifically, in FIG. 6, centers CS11, CS12, CS13, and CS14 are set for the multiple specific regions SR1, SR2, SR3, and SR4, respectively. In FIG. 6, the centers CS11, CS12, CS13, and CS14 are arranged in the order of center CS14, center CS13, center CS11, and center CS12, in order of distance from the specific flow path 100S. When the multiple specific regions SR1, SR2, SR3, and SR4 have this relative positional relationship with respect to one another, the length of the portion where the flow path forming member 11 and the joint 14 contact in the specific region SR1 is shorter than the length of the portion where the flow path forming member 11 and the joint 14 contact in the specific region SR3. Furthermore, the length of the portion where the flow path forming member 11 and the joint 14 contact in the specific region SR3 is shorter than the length of the portion where the flow path forming member 11 and the joint 14 contact in the specific region SR4. Conversely, the length of the portion where the flow path forming member 11 and the joint 14 do not contact, i.e., the gap 110, decreases with increasing distance from the specific flow path 100S. This relationship in the length of the portion where the flow path forming member 11 and the joint 14 contact each other also applies to the portions between the flow path forming member 12 and the joint 14, between the flow path forming member 12 and the joint 15, and between the flow path forming member 13 and the joint 15.

[0032] FIG. 7 is a fourth diagram illustrating features of the holding device 1 of this embodiment. FIG. 7 shows the results of measuring the length of the contact portion between the flow path forming member 11 and the joint 14 for the first member 10 of this embodiment. In FIG. 7, the centers of the captured "SEM images" are set to positions 0.1 mm, 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, and 2.5 mm from the flow path 100. The "SEM images" shown in FIG. 7 were captured so that the distance between the flow path forming member 11 and the joint 14 was 120 μm. Each of the six "SEM images" is marked with a dotted white frame WB indicating the portion where the flow path forming member 11 and the joint 14 do not contact each other.

[0033] FIG. 7 shows the "length (μm) of the non-contact portion" between the flow path forming member 11 and the joint 14, measured using each of six "SEM images." FIG. 7 also shows the "non-bonding rate (%)," which is the length of the non-contact portion relative to a length of 120 μm included in the SEM image, using the measured length of the non-contact portion between the flow path forming member E12 and the joint E14. As shown in FIG. 7, it was confirmed that the "length (μm) of the non-contact portion" increases as the "distance from the flow path (mm)" decreases, and the "non-bonding rate (%)" increases as the "distance from the flow path (mm)" decreases. In other words, it can be said that the smaller the "distance from the flow path (mm)," the more gaps 110 are formed between the flow path forming member 11 and the joint 14.

[0034] Next, we will explain the method for manufacturing the holding device 1. In the method for manufacturing the holding device 1, the first member 10 and the second member 20 are separately manufactured, and then the first member 10 and the second member 20 are joined together.

[0035] In fabricating the first member 10, first, a plurality of silicon carbide disk-shaped members and a plurality of aluminum disk-shaped members are prepared. One of the plurality of silicon carbide disk-shaped members is machined to have a space 12c that will become the flow path 100. An aluminum disk-shaped member is placed on each of a pair of main surfaces of the silicon carbide disk-shaped member with the space 12c machined therein, and a stack is fabricated using the remaining silicon carbide disk-shaped members, sandwiching the silicon carbide disk-shaped member machined together with the aluminum disk-shaped member. The fabricated stack is heated to a predetermined temperature while applying pressure, thereby bonding the plurality of silicon carbide disk-shaped members together with the aluminum disk-shaped member, and the first member 10 having the flow path 100 is fabricated.

[0036] In the fabrication of the first member 10 of this embodiment, when pressure is applied while the laminate is heated, the gaps 110 are formed by adjusting both the temperature of the laminate being heated and the pressure applied to the laminate. As an example, in the first member 10, when the temperature of the laminate being heated is 580°C, the gaps 110 communicating with the flow path 100 can be formed within an appropriate range (e.g., the range R1 shown in FIG. 3 ) by applying a pressure of 5 MPa to 13 MPa to the laminate. As another example, when the temperature of the laminate being heated is 600°C, the gaps 110 can be formed within an appropriate range by applying a pressure of 3 MPa to 10 MPa to the laminate. In this manner, by adjusting both the temperature and the pressure, the gaps 110 are formed between the flow path forming members 11, 12, and 13 and the bonding portions 14 and 15. When the temperature of the laminate being heated is low or when the pressure applied to the laminate is low, gaps are more likely to be formed, which may reduce the bonding strength of the flow path forming members at the bonding portions. If the temperature of the laminate being heated is high or if the pressure applied to the laminate is large, it becomes difficult to form gaps, which may result in a decrease in thermal uniformity in the holding device. Note that the method for producing the first member 10 is not limited to this.

[0037] In fabricating the first member 10 of this embodiment, aluminum disk-shaped members are used to bond multiple silicon carbide disk-shaped members. Therefore, when the laminate is heated and pressurized, a relatively large pressure acts on the laminate. Therefore, a large force that could destroy the bonded portions 14, 15 acts on the corners 12d (see FIG. 3 ) of the flow path 100 side of the flow path forming member 12. However, in fabricating the first member 10 of this embodiment, the flow path forming members 11, 12, 13 are bonded to the bonded portions 14, 15 so that gaps 110 are formed between the flow path forming members 11, 12, 13 and the bonded portions 14, 15, and so that the bonded areas between the flow path forming members 11, 12, 13 and the bonded portions 14, 15 gradually increase with increasing distance from the end portion 14a. This allows the stress acting on the corners 12d to be dispersed, thereby preventing damage to the first member 10.

[0038] To prepare the second member 20, first, a plurality of green sheets and a metallization paste are prepared. A pattern to become the chuck electrode 21 and the heater electrode 22 is printed on the surface of a specific green sheet from among the plurality of green sheets using the metallization paste, and then the green sheet is fired. In this way, the second member 20 having the chuck electrode 21 and the heater electrode 22 is fabricated.

[0039] After the first member 10 and the second member 20 are fabricated, a brazing filler metal containing aluminum is applied to one of a pair of main surfaces of the first member 10 or one of a pair of main surfaces of the second member 20. Next, the applied brazing filler metal is sandwiched between the first member 10 and the second member 20, and the entire assembly is heated. This produces a holding device 1 in which the first member 10 and the second member 20 are bonded via the bonding layer 30. Note that the method for manufacturing the holding device 1 is not limited to this.

[0040] FIG. 8 is a diagram illustrating the effect of the holding device 1 of this embodiment. FIG. 8 is a cross-sectional view of the first member 10 included in the holding device 1, and is a schematic diagram showing a portion of a cross-section perpendicular to the central axis C1 of the holding device 1. The cross-section shown in FIG. 8 is a cross-section including the flow path 100, for example, a cross-section passing near the other main surface 11b of the flow path forming member 11. In FIG. 8, the flow of the refrigerant in the flow path 100 is indicated by a white arrow F1. In the holding device 1 of this embodiment, as shown in FIG. 8, a gap 110 communicating with the flow path 100 is formed. Therefore, the refrigerant flowing through the flow path 100 also flows into the gap 110, as indicated by a white arrow F2 in FIG. 8. As a result, when the holding device 1 is viewed from the mounting surface 20a side (z-axis direction), the range in which the refrigerant flows is the sum of the range of the flow path 100 and the gap 110, thereby improving the thermal uniformity on the mounting surface 20a.

[0041] According to the holding device 1 of this embodiment described above, the gaps 110 formed between the flow path forming members 11, 12, and 13 and the joints 14 and 15 communicate with the flow path 100, allowing the refrigerant flowing through the flow path 100 to flow in and out. This allows the refrigerant to spread over a wider area inside the holding device 1 than the area occupied by the flow path 100. This allows the temperature uniformity of the holding device 1 to be improved.

[0042] Furthermore, according to the holding device 1 of this embodiment, each of the flow path forming members 11, 12, and 13, each having a pair of main surfaces 11a, 11b, 12a, 12b, 13a, and 13b, is arranged parallel to the mounting surface 20a. The joints 14 and 15 contact one of the main surfaces 11b, 12a, 12b, and 13a among the pair of main surfaces 11a, 11b, 12a, 12b, and 13a and 13b of the flow path forming members 11, 12, and 13. As a result, the gap 110 through which the refrigerant flows in and out is formed along a direction substantially parallel to the mounting surface 20a, thereby improving the thermal uniformity on the mounting surface 20a.

[0043] Furthermore, according to the holding device 1 of this embodiment, when a first specific region SR1 including the gap between the flow path forming member 11 and the joint 14 and a second specific region SR2 closer to the specific flow path 100S than the first specific flow region are defined in a cross section of the holding device 1 having a plurality of flow paths 100, the length of the portion in the second specific region SR2 where the flow path forming member 11 and the joint 14 contact each other is shorter than the length of the portion in the first specific region SR1 where the flow path forming member 11 and the joint 14 contact each other. That is, in the second specific region SR2, which is relatively close to the specific flow path 100S, a relatively large number of portions where the flow path forming member 11 and the joint 14 do not contact each other, i.e., gaps 110, are formed. This increases the range through which the refrigerant can be distributed, while in the first specific region SR1, which is relatively far from the specific flow path 100S, the portion where the flow path forming member 11 and the joint 14 contact each other is longer, thereby ensuring reliable joining of the flow path forming member 11 and the flow path forming member 12 via the joint 14.

[0044] Furthermore, according to the holding device 1 of this embodiment, the flow path forming members 11, 12, 13 and the joints 14, 15 are in contact with each other such that the length of the contact portion between the flow path forming members 11, 12, 13 and the joints 14, 15 becomes shorter as the center of the specific region approaches the specific flow path 100S. This allows the range over which the refrigerant is distributed to be further widened, while also increasing the joining force between the flow path forming members 11, 12, 13 via the joints 14, 15.

[0045] Furthermore, according to the holding device 1 of this embodiment, in manufacturing the first member 10, the flow path forming members 11, 12, 13 are joined to the joining portions 14, 15 so that the joining area between the flow path forming members 11, 12, 13 and the joining portions 14, 15 gradually increases with increasing distance from the end portion 14 a. This allows the stress acting on the corner portion 12 d of the flow path forming member 12 to be dispersed, thereby preventing damage to the first member 10.

[0046] Furthermore, according to the holding device 1 of this embodiment, the ends of the joints 14 and 15 on the flow path 100 side are formed to protrude, which makes it easier for the flow of the refrigerant flowing through the flow path 100 to become turbulent. That is, since the flow of the refrigerant is easily turbulent, heat exchange between the refrigerant and the flow path forming members 11, 12, and 13 and the joints 14 and 15 is promoted. This makes it possible to improve the cooling efficiency of the refrigerant.

[0047] Furthermore, according to the holding device 1 of this embodiment, the joints 14 and 15 are made of aluminum, which has relatively high thermal conductivity. This makes it easier for the cold heat of the refrigerant to be transferred to the flow path forming members 11, 12, and 13 via the joints 14 and 15, thereby improving the cooling performance of the holding device 1.

[0048] Second Embodiment 9 is a cross-sectional view of the holding device 2 of the second embodiment. The holding device 2 of the second embodiment is different from the holding device 1 of the first embodiment (FIG. 2) in the configuration of the first member.

[0049] The holding device 2 of the second embodiment includes a first member 40, a second member 20, and a bonding layer 30. The holding device 2 is, for example, an electrostatic chuck that is provided in an etching device or the like and holds the wafer W by attracting it with electrostatic attraction.

[0050] The first member 40 is a substantially circular member made mainly of silicon carbide (SiC). The first member 40 includes a plurality of flow path forming members 11, 12, and 13 that form a flow path 400 through which the refrigerant flows, and bonding portions 44 and 15 that bond the plurality of flow path forming members 11, 12, and 13 together. As shown in FIG. 9 , the bonding portion 44 is disposed over the entire other main surface 11b of the flow path forming member 11, and bonds the flow path forming member 11 and the flow path forming member 12 together.

[0051] In the holding device 2, gaps 410 communicating with the flow path 400 are formed between the flow path forming member 12 and the joint 44, between the flow path forming member 12 and the joint 15, and between the flow path forming member 13 and the joint 15. In the holding device 2, a relatively large number of gaps 410 are formed on the flow path 400 side between the flow path forming members 12, 13 and the joints 44, 15. As a result, when the holding device 2 is viewed from the mounting surface 20a side, the range through which the refrigerant flows is the sum of the range of the flow paths 400 and the gaps 410, thereby improving the thermal uniformity on the mounting surface 20a.

[0052] According to the holding device 2 of this embodiment described above, the gaps 410 formed between the flow path forming members 12, 13 and the joints 44, 15 communicate with the flow path 400, allowing the refrigerant flowing through the flow path 400 to flow in and out. This allows the refrigerant to spread over a wider area inside the holding device 2 than the area occupied by the flow path 400. This allows the temperature uniformity of the holding device 2 to be improved.

[0053] <Third embodiment> 10 is a cross-sectional view of the holding device 3 of the third embodiment. The holding device 3 of the third embodiment differs from the holding device 1 of the first embodiment (FIG. 2) in the configuration of the first member.

[0054] The holding device 3 of the third embodiment includes a first member 50, a second member 20, and a bonding layer 30. The holding device 3 is, for example, an electrostatic chuck that is provided in an etching device or the like and holds the wafer W by attracting it with electrostatic attraction.

[0055] The first member 50 is a substantially circular member made mainly of silicon carbide (SiC). The first member 50 includes a plurality of flow path forming members 11, 12, and 13 that form a flow path 500 through which a refrigerant flows, and bonding portions 54 and 55 that bond the plurality of flow path forming members 11, 12, and 13 together. As shown in FIG. 10 , the bonding portion 54 is disposed over the entire surface of the other main surface 11b of the flow path forming member 11, and bonds the flow path forming member 11 and the flow path forming member 12 together. As shown in FIG. 10 , the bonding portion 55 is disposed over the entire surface of one main surface 13a of the flow path forming member 13, and bonds the flow path forming member 12 and the flow path forming member 13 together.

[0056] In the holding device 3, gaps 510 communicating with the flow path 500 are formed between the flow path forming member 12 and the joint 54, and between the flow path forming member 12 and the joint 55. In the holding device 3, a relatively large number of gaps 510 are formed on the flow path 500 side between the flow path forming member 12 and the joints 54, 55. As a result, when the holding device 3 is viewed from the mounting surface 20a side, the range through which the refrigerant flows is the sum of the range of the flow paths 500 and the gaps 510, thereby improving the thermal uniformity on the mounting surface 20a.

[0057] According to the holding device 3 of this embodiment described above, the gap 510 formed between the flow path forming member 12 and the joints 54, 55 communicates with the flow path 500, allowing the refrigerant flowing through the flow path 500 to flow in and out. This allows the refrigerant to spread over a wider area inside the holding device 3 than the area occupied by the flow path 500. This allows the temperature uniformity of the holding device 3 to be improved.

[0058] <Fourth embodiment> 11 is a cross-sectional view of the holding device 4 of the fourth embodiment. The holding device 4 of the fourth embodiment is different from the holding device 1 of the first embodiment (FIG. 2) in the configuration of the first member.

[0059] The holding device 4 of the fourth embodiment includes a first member 60, a second member 20, and a bonding layer 30. The holding device 4 is, for example, an electrostatic chuck that is provided in an etching device or the like and holds the wafer W by attracting it with electrostatic attraction.

[0060] The first member 60 is a substantially circular member made primarily of silicon carbide (SiC). The first member 60 includes a plurality of flow path forming members 61, 13 that form a flow path 600 through which the refrigerant flows, and a joint 62 that joins the flow path forming members 61 and 13. The flow path forming member 61 is made of silicon carbide (SiC). The flow path forming member 61 has a plate shape with a pair of main surfaces 61a, 61b, and is disposed so that each of the pair of main surfaces 61a, 61b is parallel to the mounting surface 20a. A space 61c that becomes the flow path 600 is formed in the other main surface 61b of the pair of main surfaces 61a, 61b of the flow path forming member 61. The joint 62 is in contact with the other main surface 61b of the flow path forming member 61, as shown in FIG. 11 . The joint 62 joins the flow path forming member 61 and the flow path forming member 13.

[0061] In the holding device 4, gaps 610 communicating with the flow path 600 are formed between the flow path forming member 61 and the joint 62, and between the flow path forming member 13 and the joint 62. In the holding device 4, a relatively large number of gaps 610 are formed on the flow path 600 side between the flow path forming members 61, 13 and the joint 62. As a result, when the holding device 4 is viewed from the mounting surface 20a side, the range through which the refrigerant flows is the sum of the range of the flow paths 600 and the gaps 610, thereby improving the thermal uniformity on the mounting surface 20a.

[0062] According to the holding device 4 of this embodiment described above, the gap 610 formed between the flow path forming members 61, 13 and the joint portion 62 communicates with the flow path 600, allowing the refrigerant flowing through the flow path 600 to flow in and out. This allows the refrigerant to spread over a wider area inside the holding device 4 than the area occupied by the flow path 600. This allows the temperature uniformity of the holding device 4 to be improved.

[0063] Fifth Embodiment 12 is a cross-sectional view of the holding device 5 of the fifth embodiment. The holding device 5 of the fifth embodiment is different from the holding device 1 of the first embodiment (FIG. 2) in the configuration of the first member.

[0064] The holding device 5 of the fifth embodiment includes a first member 70, a second member 20, and a bonding layer 30. The holding device 5 is, for example, an electrostatic chuck that is provided in an etching device or the like and holds the wafer W by attracting it with electrostatic attraction.

[0065] The first member 70 is a substantially circular member made mainly of silicon carbide (SiC). The first member 70 includes a plurality of flow path forming members 61, 13 that form a flow path 700 through which the refrigerant flows, and a joint 72 that joins the flow path forming members 61 and 13. As shown in FIG. 12 , the joint 72 is disposed over the entire surface of one main surface 13a of the flow path forming member 13, and joins the flow path forming member 61 and the flow path forming member 13.

[0066] In the holding device 5, gaps 710 communicating with the flow path 700 are formed between the flow path forming members 61 and the joint 72. In the holding device 5, a relatively large number of gaps 710 are formed on the flow path 700 side between the flow path forming members 61, 13 and the joint 72. As a result, when the holding device 5 is viewed from the mounting surface 20a side, the range through which the refrigerant flows is the sum of the range of the flow paths 700 and the gaps 710, thereby improving the temperature uniformity on the mounting surface 20a.

[0067] According to the holding device 5 of this embodiment described above, the gap 710 formed between the flow path forming member 61 and the joint portion 72 communicates with the flow path 700, allowing the refrigerant flowing through the flow path 700 to flow in and out. This allows the refrigerant to spread over a wider area inside the holding device 5 than the area occupied by the flow path 700. This allows the temperature uniformity of the holding device 5 to be improved.

[0068] Sixth Embodiment 13 is a cross-sectional view of a holding device 6 of the sixth embodiment. The holding device 6 of the sixth embodiment is different from the holding device 1 of the first embodiment (FIG. 3) in the shape of the joint portion of the first member.

[0069] The holding device 6 of the sixth embodiment includes a first member 80, a second member 20, and a bonding layer 30. The holding device 6 is, for example, an electrostatic chuck that is provided in an etching device or the like and holds the wafer W by attracting it with electrostatic attraction.

[0070] The first member 80 is a substantially circular member made mainly of silicon carbide (SiC). The first member 80 includes a plurality of flow path forming members 11, 12, and 13 that form a flow path 800 through which the refrigerant flows, and joints 84 and 15 that join the plurality of flow path forming members 11, 12, and 13. As shown in FIG. 13 , the joint 84 joins the flow path forming member 11 and the flow path forming member 12. In the holding device 6 of this embodiment, a gap 810 that communicates with the flow path 800 is formed between the flow path forming members 11, 12, and 13 and the joints 14 and 15.

[0071] The joint 84 is formed such that an end 84a on the flow path 800 side protrudes into the flow path 800. That is, the end 84a of the joint 84 is located inside the flow path 800, as shown in FIG. 13 . In the holding device 6, gaps 810 communicating with the flow path 800 are formed between the flow path forming member 11 and the joint 84 and between the flow path forming member 12 and the joint 84. In this embodiment, as shown in FIG. 13 , the gaps 810 are formed to be included in a range R6 between a position P61 that is 0.1 mm away in the negative y-axis direction from an inner wall surface 12e that forms the flow path 800 of the flow path forming member 12, and a position P62 that is 3 mm away in the negative y-axis direction from the inner wall surface 12e of the flow path forming member 12.

[0072] According to the holding device 6 of this embodiment described above, the gaps 810 formed between the flow path forming members 11, 12, and 13 and the joints 84 and 15 communicate with the flow path 800, allowing the refrigerant flowing through the flow path 800 to flow in and out. This allows the refrigerant to spread over a wider area inside the holding device 6 than the area occupied by the flow path 800. This allows the temperature uniformity of the holding device 6 to be improved.

[0073] Furthermore, according to the holding device 6 of this embodiment, the end 84a of the joint 84 on the flow path 800 side is formed so as to protrude into the flow path 800, which makes it easier for the flow of the refrigerant flowing through the flow path 800 to become turbulent. In other words, since the flow of the refrigerant is more likely to become turbulent, heat exchange between the refrigerant and the flow path forming members 11, 12, and 13 and the joints 84 and 15 is further promoted. This makes it possible to improve the cooling efficiency of the refrigerant.

[0074] <Modification of this embodiment> The present invention is not limited to the above-described embodiment, and can be embodied in various forms without departing from the spirit of the invention. For example, the following modifications are also possible.

[0075] [Variation 1] In the above-described embodiment, the holding device is a so-called electrostatic chuck that is installed in an etching device or the like and holds the wafer W by attracting it with electrostatic attraction, but the technical field to which the holding device is applied is not limited to this. It may be applied to any technical field that requires holding an object in some way. Therefore, the method of holding the object is not limited to attracting it with electrostatic attraction.

[0076] [Variation 2] In the above-described embodiment, the plate-shaped flow path forming member having a pair of main surfaces is arranged so that each of the pair of main surfaces is parallel to the mounting surface. The shape of the flow path forming member and the positional relationship between the pair of main surfaces of the flow path forming member and the mounting surface are not limited to this. Each of the pair of main surfaces of the flow path forming member does not have to be arranged parallel to the mounting surface. In this case, the gap formed between the flow path forming member and the joint portion may be formed along a direction other than a direction substantially parallel to the mounting surface.

[0077] [Variation 3] In the above-described embodiment, the relationship between the lengths of the contact portions between the flow path forming member and the joint portion in the plurality of specific regions including between the flow path forming member and the joint portion is such that the length closer to the specific flow path is shorter than the length farther from the specific flow path, and the closer to the specific flow path, the shorter the length becomes. The relationship between the lengths of the contact portions between the flow path forming member and the joint portion in the plurality of specific regions is not limited to this.

[0078] [Variation 4] In the above-described embodiment, the relationship regarding the length of the portion where the flow path forming member and the joint portion are in contact with each other in the multiple specific regions described with reference to Fig. 6 is the same between each of the flow path forming members 11, 12, 13 of the first member and the joint portions 14, 15. However, such a relationship does not have to be established between all of the flow path forming members 11, 12, 13 and the joint portions 14, 15. Even if such a relationship is established in only some of the specific regions, it is possible to improve the thermal uniformity.

[0079] [Variation 5] In the above-described embodiment, the end of the joint on the flow path side is formed to protrude. The shape of the end of the joint on the flow path side is not limited to this. Although it may have a flat shape, forming it in a protruding shape can disrupt the flow of the refrigerant flowing through the flow path, thereby improving the cooling efficiency of the refrigerant.

[0080] [Variation 6] In the above-described embodiment, the joints are formed of metal, but the material for forming the joints is not limited to this.

[0081] [Variation 7] In the above-described embodiment, the holding device includes a first member, a second member, and a bonding layer that bonds the first member and the second member. However, the configuration of the holding device is not limited to this. It is sufficient that the holding device includes a plurality of flow path forming members and a bonding portion that bonds the flow path forming members to each other.

[0082] This aspect has been described above based on embodiments and modifications. However, the above-described embodiments are intended to facilitate understanding of this aspect and are not intended to limit this aspect. This aspect may be modified or improved without departing from the spirit and scope of the claims, and equivalents thereof are included in this aspect. Furthermore, if a technical feature is not described as essential in this specification, it may be deleted as appropriate.

[0083] <Application example 1> A holding device for holding an object, a plurality of flow path forming members that form a flow path through which the refrigerant flows; a joining portion that joins the plurality of flow path forming members to each other, A gap communicating with the flow path is formed between the flow path forming member and the joint portion. holding device. <Application example 2> The holding device according to Application Example 1 may further include: a placement surface on which the object is placed, Each of the plurality of flow path forming members includes: It has a plate shape with a pair of main surfaces, The pair of main surfaces are arranged so as to be parallel to the placement surface, the joint portion is in contact with at least one of a pair of main surfaces of the flow path forming member, A plurality of the flow path forming members and the joint portion are stacked. holding device. <Application example 3> The holding device according to Application Example 1 or Application Example 2, In a cross section including a central axis of the holding device and including a plurality of cross sections of the flow path, a first specific region as a specific region including a region between the flow path forming member and the joint portion, and a second specific region located between the first specific region and a specific flow path among the plurality of flow paths that is closest to the first specific region, a length of a portion where the flow path forming member and the joint portion included in the second specific region are in contact with each other is shorter than a length of a portion where the flow path forming member and the joint portion included in the first specific region are in contact with each other. holding device. <Application Example 4> The holding device according to any one of Application Examples 1 to 3, a length of a portion where the flow path forming member and the joint portion included in the specific region are in contact with each other becomes shorter as the center of the specific region approaches the specific flow path; holding device. <Application example 5> The holding device according to any one of Application Examples 1 to 4, The end of the joint portion on the flow path side is formed to protrude. holding device. <Application Example 6> The holding device according to any one of Application Examples 1 to 5, The joint is formed of metal. holding device. [Explanation of symbols]

[0084] 1,2,3,4,5,6...holding device 11, 12, 13, 61 ... Flow path forming member 11a,11b,12a,12b,13a,13b,61a,61b...main surface 14,15,44,54,55,62,72,84…Joint part 100S...Specific flow path 14a, 84a ... (joint) end 20a...Placement surface 100, 400, 500, 600, 700, 800...flow path 110,410,510,610,710,810 …gaps C1...center axis SR1: First specific region SR2: Second specific area SR3: Third specific area SR4...Fourth specific region W...wafer

Claims

1. A holding device for holding an object, a placement surface on which the object is placed; a plurality of flow path forming members that form a flow path through which the refrigerant flows; a joining portion that joins the plurality of flow path forming members to each other, a gap communicating with the flow path is formed between the flow path forming member and the joint portion, Each of the plurality of flow path forming members includes: It has a plate shape with a pair of main surfaces, The pair of main surfaces are arranged so as to be parallel to the placement surface, the joint portion is in contact with at least one of a pair of main surfaces of the flow path forming member, A plurality of the flow path forming members and the joint portion are stacked. holding device.

2. 2. The holding device of claim 1, The end of the joint portion on the flow path side is formed to protrude. holding device.

3. 3. The holding device according to claim 1 or 2, The joint is formed of metal. holding device.

4. A holding device for holding an object, a plurality of flow path forming members that form a flow path through which the refrigerant flows; a joining portion that joins the plurality of flow path forming members to each other, a gap communicating with the flow path is formed between the flow path forming member and the joint portion, In a cross section including a central axis of the holding device and including a plurality of cross sections of the flow path, a first specific region as a specific region including a region between the flow path forming member and the joint portion, and a second specific region located between the first specific region and a specific flow path among the plurality of flow paths that is closest to the first specific region, a length of a portion where the flow path forming member and the joint portion included in the second specific region are in contact with each other is shorter than a length of a portion where the flow path forming member and the joint portion included in the first specific region are in contact with each other, holding device.

5. 5. The holding device according to claim 4, a length of a portion where the flow path forming member and the joint portion included in the specific region are in contact with each other becomes shorter as the center of the specific region approaches the specific flow path; holding device.

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