Base and holding device

Abstract

This invention provides a technology to improve the surface temperature distribution on a base. [Solution] The base comprises a plate-shaped member having a first main surface on which a substrate on which an object to be held is placed is arranged, and a second main surface formed on the opposite side of the first main surface, and a flow path disposed inside the plate-shaped member through which a refrigerant flows. In a cross-section of the plate-shaped member in the thickness direction including the central axis of the plate-shaped member, the cross-section of the plate-shaped member is divided equally into three parts in the thickness direction, and the region on the first main surface side is designated as the first region. The total cross-sectional area of ​​the flow path included in the first region is 0% or more and 30% or less of the total cross-sectional area of ​​the flow path.

Description

Technical Field

[0001] The present invention relates to a base and a holding device.

Background Art

[0002] Conventionally, a base used in a holding device for holding a substrate has been known (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, even with the prior art such as Patent Document 1, there is still room for improvement in the technology for improving the temperature distribution on the surface of the base.

[0005] The present invention has been made to solve the above-described problems, and an object thereof is to provide a technology for improving the temperature distribution on the surface of the base.

Means for Solving the Problems

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

[0007] (1) According to one embodiment of the present invention, a base for use in a holding device is provided. The base comprises a plate-shaped member having a first main surface on which a substrate on which an object to be held is placed is arranged, and a second main surface formed on the opposite side of the first main surface, and a flow path disposed inside the plate-shaped member through which a refrigerant flows, wherein in a cross section of the plate-shaped member in the thickness direction including the central axis of the plate-shaped member, the cross section of the plate-shaped member is divided equally into three parts in the thickness direction, and the region on the first main surface side is designated as the first region, and the total cross-sectional area of ​​the flow path included in the first region is 0% or more and 30% or less of the total cross-sectional area of ​​the flow path.

[0008] In this configuration, the cross-section of the plate-shaped member on which the flow channels are formed is divided equally into three parts in the thickness direction, and the region on the first main surface side is designated as the first region. The total cross-sectional area of ​​the flow channels included in the first region is between 0% and 30% of the total cross-sectional area of ​​the flow channels. In other words, the distance between the first main surface on which the base material is placed and the flow channels of the plate-shaped member is relatively long. As a result, the ratio of the distance of the heat transfer path in the portion of the first main surface that is not directly above the flow channels to the distance of the heat transfer path in the portion directly above the flow channels is relatively small, thus reducing the temperature distribution due to differences in the distance of the heat transfer paths. Therefore, the temperature distribution on the first main surface can be improved.

[0009] (2) In the base of the above form, if the cross section of the plate-shaped member in the thickness direction is divided equally into three parts in the thickness direction, the region on the second main surface side is designated as the third region, and the region between the first region and the third region is designated as the second region, then the total cross-sectional area of ​​the flow channels included in the second region may be 0% or more and 85% or less of the total cross-sectional area of ​​the flow channels, and the total cross-sectional area of ​​the flow channels included in the third region may be 15% or more and 100% or less of the total cross-sectional area of ​​the flow channels. According to this configuration, when the cross section of the plate-shaped member on which the flow channels are formed is divided equally into three parts in the thickness direction, the total cross-sectional area of ​​the flow channels included in the second region is 0% or more and 85% or less of the total cross-sectional area of ​​the flow channels, and the total cross-sectional area of ​​the flow channels included in the third region is 15% or more and 100% or less of the total cross-sectional area of ​​the flow channels. That is, the majority of the flow channels are formed mainly on the second main surface side of the plate-shaped member. As a result, much of the refrigerant flows at a relatively distant location from the first main surface, further reducing the ratio of the heat transfer path distance in the portion of the first main surface that is located away from the flow path to the heat transfer path distance in the portion located directly above the flow path. Therefore, the temperature distribution due to differences in heat transfer path distance can be further reduced, thereby further improving the temperature distribution on the first main surface.

[0010] (3) The base of the above configuration may further include a heat transfer suppression portion disposed between the flow path and the first main surface, which is made of a material with a thermal conductivity lower than that of the material forming the plate-shaped member. With this configuration, the cooling effect of the refrigerant flowing through the flow path is less likely to be transmitted to the portion of the first main surface located directly above the flow path. As a result, the temperature of the portion of the first main surface located directly above the flow path, which is easily cooled by the refrigerant flowing through the flow path, tends to be closer to the ambient temperature. Therefore, the temperature distribution on the first main surface can be further improved.

[0011] (4) In the base of the above form, in the cross section in the thickness direction of the plate-shaped member, the flow channels are arranged in a plurality along the width direction of the plate-shaped member, and if G is the distance between adjacent flow channels among the plurality of flow channels, and W is the average width of each of the adjacent flow channels, then equation (1) may be satisfied. 0.1 ≤ G / W ≤ 1 ···(1) With this configuration, the distance G between adjacent flow paths is small relative to the average width W of each adjacent flow path, so the cooling effect of the refrigerant flowing through the flow paths is easily transmitted evenly across the entire first main surface. This further improves the temperature distribution on the first main surface.

[0012] (5) In the base of the above form, if D1 is the distance between the first main surface and the flow path in the cross-section in the thickness direction of the plate-like member, then equation (2) may be satisfied. D1≧G ···(2) In this configuration, the distance D1 between the first main surface and the flow path is greater than the distance G between adjacent flow paths. Therefore, the cooling effect of the refrigerant flowing through the flow path is more evenly distributed across the entire first main surface. This further improves the temperature distribution on the first main surface.

[0013] (6) In the base of the above form, if the average depth of each of the adjacent flow channels in the cross section in the thickness direction of the plate-shaped member is H and the thickness of the plate-shaped member is D, then equation (3) may be satisfied. 0.1 ≤ H / D < 0.6 ···(3) In this configuration, the average H of the depths of adjacent channels relative to the thickness D of the plate-shaped member is 0.1 or greater, which allows for a certain degree of cooling effect from the refrigerant flowing through the channels, and is less than 0.6, which allows for the maintenance of structural strength. This makes it possible to achieve both the strength of the plate-shaped member on which the substrate on which the object to be held is placed and the cooling effect from the refrigerant.

[0014] (7) In the base of the above embodiment, the plate-shaped member comprises a first base having the first main surface and a second base having the second main surface and having the flow channel formed thereon, wherein the thermal conductivity of the material forming the first base may be greater than that of the material forming the second base. According to this configuration, the plate-shaped member has a first base having the first main surface and a second base having the second main surface. A flow channel is formed in the second base, and the thermal conductivity of the material forming the first base is greater than that of the material forming the second base. As a result, the thermal resistance between the first main surface and the flow channel becomes relatively small, and the temperature distribution due to differences in the distance of the heat transfer path can be further reduced. Therefore, the temperature distribution on the first main surface can be further improved.

[0015] (8) The base of the above configuration may be made of ceramics. With this configuration, the base is made of ceramics. This makes it possible to improve the corrosion resistance of the base to refrigerants.

[0016] (9) According to another embodiment of the present invention, a holding device is provided. This holding device comprises the base described above and a substrate bonded to the first main surface, the substrate having a mounting surface on which an object to be held is placed. With this configuration, the holding device has a base with a small temperature distribution on the first main surface. This makes it possible to reduce the temperature distribution on the mounting surface of the substrate.

[0017] (10) In the holding device of the above form, if the distance between the first main surface and the flow path in the thickness direction of the plate-shaped member is D1 and the thickness of the base material is D2, then equation (4) may be satisfied. D1 ≤ D2 ···(4) According to this configuration, since the thickness D2 of the base material is equal to or greater than the distance D1 between the first main surface and the flow path, the ratio of the distance of the heat transfer path of the portion located directly above the flow path on the mounting surface to the distance of the heat transfer path of the portion away from directly above the flow path becomes relatively small. As a result, the temperature distribution due to the difference in the distance of the heat transfer path can be reduced, so that the temperature distribution on the mounting surface can be improved.

[0018] (11) In the holding device of the above aspect, in the cross section in the thickness direction of the plate-like member, a plurality of the flow paths are arranged side by side along the width direction of the plate-like member. When the distance between adjacent flow paths among the plurality of flow paths is G and the thickness of the base material is D2, the following formula (5) may be satisfied. G≦D2 ···(5) According to this configuration, since the distance G between adjacent flow paths of the base with respect to the thickness D2 of the base material is small, the cooling effect by the refrigerant flowing through the flow path is likely to be evenly transmitted to the entire mounting surface. As a result, the temperature distribution on the mounting surface can be further improved.

[0019] Note that the present invention can be realized in various aspects. For example, a method for manufacturing a base, a method for manufacturing a holding device, a system including a base or a holding device, a control method for a holding device and a system including the holding device, a computer program for causing a substrate to be held in a holding device and a system including the holding device, a server device for distributing the computer program, and a non-transitory storage medium storing the computer program.

Brief Description of the Drawings

[0020] [Figure 1] It is a perspective view of the holding device of the first embodiment. [Figure 2] It is a cross-sectional view of the holding device of the first embodiment. [Figure 3] It is an enlarged view of part A in FIG. 2. [Figure 4] It is a schematic diagram for explaining the heat transfer path in the base of the comparative example. [Figure 5]It is a schematic diagram for explaining the heat transfer path in the base of the first embodiment. [Figure 6] It is an enlarged cross-sectional view of the holding device of the second embodiment. [Figure 7] It is an enlarged cross-sectional view of the holding device of the third embodiment. [Figure 8] It is an enlarged cross-sectional view of the holding device of the fourth embodiment. [Figure 9] It is an enlarged cross-sectional view of the holding device of the fifth embodiment. [Figure 10] It is an enlarged cross-sectional view of the holding device of the sixth embodiment. [Figure 11] It is a cross-sectional view of the holding device of the seventh embodiment. [Figure 12] It is an enlarged view of part B in FIG. 11. [Figure 13] It is an enlarged cross-sectional view of the holding device of the eighth embodiment. [Figure 14] It is an enlarged cross-sectional view of a modified example of the holding device of the first embodiment. [Figure 15] It is an enlarged cross-sectional view of a modified example of the holding device of the fifth embodiment.

Modes for Carrying Out the Invention

[0021] <First Embodiment> Figure 1 is a perspective view of the holding device 1 of this embodiment. Figure 2 is a cross-sectional view of the holding device 1 of this embodiment. The holding device 1 of this embodiment is an electrostatic chuck that holds a substrate Sb by attracting it with electrostatic force. The electrostatic chuck is used, for example, as a table on which to place the substrate Sb in an etching process using plasma in a chamber equipped with the electrostatic chuck. The holding device 1 of this embodiment comprises a base material 10, a base 20, and a joint 30. In the holding device 1, the base material 10, the joint 30, and the base 20 are stacked in that order. In Figures 1 and 2, for convenience, the stacking direction of the base material 10 and the base 20 is shown as the z-axis direction, the direction perpendicular to the z-axis is shown as the x-axis direction, and the direction perpendicular to the z-axis and x-axis is shown as the y-axis direction. For the sake of explanation, the relative sizes of the base material 10, the base 20, and the joint 30 in Figures 1 and 2 differ from the actual relationships.

[0022] The base material 10 is a disc-shaped member made of ceramics. In this embodiment, the base material 10 is made of aluminum nitride (AlN). However, the base material 10 may also be made of aluminum oxide (Al2O3) or a dielectric ceramic.

[0023] The base material 10 has a first main surface 10a and a second main surface 10b. A mounting surface 11 on which a substrate Sb is placed is formed on the first main surface 10a. The first main surface 10a of the base material 10 has a plurality of protrusions 10c and an annular protrusion 10d formed so as to surround the plurality of protrusions 10c. The mounting surface 11 is formed by the tip surfaces of each of the plurality of protrusions 10c and the positive end surface in the z-axis direction of the annular protrusion 10d. Note that the base material 10 does not have to have a plurality of protrusions 10c and an annular protrusion 10d. A focus ring base material for mounting a focus ring may be arranged outside the annular protrusion 10d of the base material 10.

[0024] The substrate 10 incorporates a chuck electrode 12 made of a conductive material. The chuck electrode 12 is connected to an external power supply via electrode terminals (not shown). When power is supplied from the external power supply, the chuck electrode 12 generates an electrostatic attraction force capable of adsorbing and holding the substrate Sb to the mounting surface 11. In addition to the chuck electrode 12, the substrate 10 may also incorporate a high-frequency electrode for plasma or a heater electrode. These electrodes may also be incorporated into the base 20.

[0025] The base 20 comprises a plate-shaped member 200 having a first main surface 20a on which the substrate 10 on which the substrate Sb is placed is positioned, and a second main surface 20b formed on the opposite side of the first main surface 20a; a flow path 21 through which a refrigerant flows, disposed inside the plate-shaped member 200; and an opening 20c formed on the second main surface 20b through which the refrigerant flowing through the flow path 21 passes. The base 20 cools the substrate Sb and the substrate 10 using the refrigerant flowing through the flow path 21.

[0026] The plate-shaped member 200 is formed of ceramics. The plate-shaped member in this embodiment is a sintered body mainly composed of silicon carbide (SiC). Here, "main component" means the component with the highest proportion. The material forming the plate-shaped member 200 is not limited to a material mainly composed of silicon carbide, but may also be made of aluminum (Al), titanium (Ti), molybdenum (Mo), tungsten (W), alloys thereof, SUS, composites of metals and ceramics such as Al-SiC, or materials mainly composed of ceramics such as aluminum nitride (AlN) or alumina (Al2O3). The thermal conductivity of the material forming the plate-shaped member 200 is preferably 70 W / (m·K) or higher, and more preferably 120 W / (m·K) or higher.

[0027] The plate-shaped member 200 in this embodiment has a substantially disc shape. The plate-shaped member 200 has a size greater than or equal to the diameter of the substrate Sb, for example, a size of 300 mm or more. The thickness of the plate-shaped member 200 is 10 mm to 50 mm, and preferably 15 mm to 30 mm.

[0028] Multiple flow channels 21 are arranged to appear in a cross-section including the central axis C1 of the holding device 1 shown in Figure 2. In this embodiment, multiple flow channels 21 are arranged along the first main surface 20a and the second main surface 20b, respectively, in a cross-section in the thickness direction (z-axis direction) of the plate-shaped member 200, including the central axis C200 of the plate-shaped member 200 that overlaps with the central axis C1 of the holding device 1. The cross-section of the flow channels 21 in this embodiment has a rectangular shape. However, the shape of the cross-section of the flow channels 21 is not limited to a rectangular shape, and may be a polygonal shape including a trapezoidal shape.

[0029] Figure 3 is an enlarged view of part A in Figure 2, and is an enlarged cross-sectional view of a part of the cross-sectional view of the holding device 1 shown in Figure 2. In this embodiment, the base 20 is such that, in the cross-section of the plate-shaped member 200 in the thickness direction, including the central axis C200 of the plate-shaped member 200, the cross-section of the plate-shaped member 200 is divided equally into three parts in the thickness direction, and the region on the first main surface 20a side is called the first region R201. The total cross-sectional area of ​​the flow channels 21 included in the first region R201 is 0% or more and 30% or less of the total cross-sectional area of ​​the flow channels 21. Specifically, the relationship between the cross-sectional area A211 of the portion 211 of the flow channels 21 included in the first region R201 and the cross-sectional area A21 of the flow channels 21 satisfies the following equation (6). When multiple flow channels 21 appear in the cross-section in the thickness direction of the plate-shaped member 200, the cross-sectional area A211 is the sum of the cross-sectional areas of the portions of each of the multiple flow channels 21 included in the first region R201, and the cross-sectional area A21 is the sum of the cross-sectional areas of each of the multiple flow channels 21. In the base 20 of this embodiment, the cross-sectional area A211 of the portion 211 of the flow channel 21 is 11% of the cross-sectional area A21 of the flow channel 21. 0 ≤ A211 / A21 ≤ 0.3 ···(6)

[0030] Here, we will explain how to set the first region R201. First, in the cross-section shown in Figure 3, we set up imaginary lines that divide the base 20 into three parts in the thickness direction (z-axis direction). Specifically, in the cross-section of the holding device 1 shown in Figure 3, we define the imaginary line passing through the first main surface 20a of the plate-shaped member 200 as division line L0, the imaginary line passing through the second main surface 20b of the plate-shaped member 200 as division line L3, and the imaginary lines dividing the space between division line L0 and division line L3 into three regions as division lines L1 and L2. Using the division lines L0, L1, L2, and L3 set in this way, the first region R201 becomes the region sandwiched between division line L0 and division line L1. Note that in Figure 3, for the sake of explanation, division line L0, shown as a dashed line, is shown offset from the first main surface 20a, and division line L3, shown as a dashed line, is shown offset from the second main surface 20b.

[0031] In this embodiment, the base 20 is constructed such that, in the cross-section of the plate-shaped member 200 in the thickness direction, the cross-section of the plate-shaped member 200 is divided equally into three parts in the thickness direction, the area on the second main surface 20b side is designated as the third region R203, and the area between the first region R201 and the third region R203 is designated as the second region R202. The total cross-sectional area of ​​the flow channels 21 included in the second region R202 is 0% to 85% of the total cross-sectional area of ​​the flow channels 21, and the total cross-sectional area of ​​the flow channels 21 included in the third region R203 is 15% to 100% of the total cross-sectional area of ​​the flow channels 21. Using the dividing lines L0, L1, L2, and L3 shown in Figure 3 above, the second region R202 is the area sandwiched between dividing line L1 and dividing line L2, and the third region R203 is the area sandwiched between dividing line L2 and dividing line L3. In this embodiment, the base 20 satisfies the following equation (7) in relation to the cross-sectional area A212 of portion 212 of the flow path 21 included in the second region R202 and the cross-sectional area A21 of the flow path 21, and satisfies the following equation (8) in relation to the cross-sectional area A213 of portion 213 of the flow path 21 included in the third region R203 and the cross-sectional area A21 of the flow path 21. When multiple flow paths 21 appear in the cross section in the thickness direction of the plate-shaped member 200, the cross-sectional area A212 is the sum of the cross-sectional areas of the portions included in the second region R202 for each of the multiple flow paths 21, and the cross-sectional area A213 is the sum of the cross-sectional areas of the portions included in the third region R203 for each of the multiple flow paths 21. In the base 20 of this embodiment, the cross-sectional area A212 of portion 212 of the flow path 21 is 57% of the cross-sectional area A21 of the flow path 21, and the cross-sectional area A213 of portion 213 of the flow path 21 is 32% of the cross-sectional area A21 of the flow path 21. 0 ≤ A212 / A21 ≤ 0.85 ···(7) 0.15 ≤ A213 / A21 ≤ 1 ···(8)

[0032] In the base 20 of this embodiment, in the cross-section in the thickness direction of the plate-shaped member 200, multiple flow channels 21 are arranged so as to be aligned along the width direction of the plate-shaped member 200. If G is the distance between adjacent flow channels 21 and W is the average width of each adjacent flow channel 21, then the following equation (1) is satisfied. Specifically, in the cross-section shown in Figure 3, the base 20 has a cross-section such that the average width W of each adjacent flow channel 21 is less than or equal to the distance G between adjacent flow channels 21. Note that "width direction of the plate-shaped member 200" refers to the x-axis direction in the cross-section of Figure 3, but it may also refer to the y-axis direction, as long as it is a direction perpendicular to the thickness direction (z-axis direction) of the plate-shaped member 200. In the base 20 of this embodiment, G / W is 0.25. 0.1 ≤ G / W ≤ 1 ···(1)

[0033] In this embodiment, the base 20 satisfies the following equation (2) when the distance between the first main surface 20a and the flow path 21 in the thickness direction cross-section of the plate-shaped member 200 is D1. Specifically, in the cross-section shown in Figure 3, the base 20 has a distance G between adjacent flow paths 21 that is less than or equal to the distance D1 between the first main surface 20a and the flow path 21. G ≤ D1 ···(2)

[0034] In this embodiment, the base 20 satisfies the following equation (3) when H is the average depth of adjacent flow channels 21 in the cross-section in the thickness direction of the plate-shaped member 200, and D is the thickness of the plate-shaped member 200. In the base 20 of this embodiment, H / D is 0.48. 0.1 ≤ H / D < 0.6 ···(3)

[0035] The opening 20c is formed on the second main surface 20b of the base 20 (see Figure 2). The opening 20c communicates with the flow path 21 and the outside of the base 20. The refrigerant flowing through the flow path 21 enters and exits through the opening 20c.

[0036] The joint portion 30 is positioned between the base material 10 and the base 20, and joins the base material 10 and the base 20. In this embodiment, the joint portion 30 is a metal joining material mainly composed of indium. However, the joint portion 30 is not limited to a metal joining material mainly composed of indium, but may also be a silicone-based organic adhesive, a brazing material containing hard or soft brazing materials, an inorganic joining material, or a metal joining material containing metals other than indium, such as gold or silver. Furthermore, the method of joining the base material 10 and the base 20 is not limited to the method using the joint portion 30, but may also be a method of fastening with bolts.

[0037] Next, the manufacturing method of the holding device 1 of this embodiment will be described. The holding device 1 is manufactured by separately manufacturing the base material 10 and the base 20, and then joining the base material 10 and the base 20 using a joint 30.

[0038] In the manufacturing method of the holding device 1, first, a base material 10 and a base 20 are prepared (preparation step). In the production of the base material 10, first, a slurry for green sheets containing aluminum nitride powder is formed into a sheet using a casting device, and the resulting molded product is dried to produce multiple green sheets. Next, a portion that will become the chuck electrode 12 is printed on a specific green sheet from among the multiple green sheets using a metallizing paste, for example, using a screen printing device. Next, a laminate of green sheets is produced by stacking multiple green sheets, including the specific green sheet on which the metallizing paste has been printed, and the base material 10 is produced by firing. Note that the manufacturing method of the base material 10 is not limited to these. For example, a binder is added to a raw material powder containing additives such as yttrium oxide to aluminum nitride powder to granulate powder, and the granulated powder is filled into a carbon mold and pressed into a flat plate shape. A flat, plate-shaped molded body is fitted with a foil-like or mesh-like planar electrode that will serve as the chuck electrode 12. Granular powder is then further filled onto the fitted planar electrode, and the body is fired while applying pressure in a uniaxial direction with a carbon punch (powder hot press method). The base material 10 can also be manufactured by this powder hot press method.

[0039] In the production of the base 20, a binder is added to a raw material powder containing silicon carbide and other additives such as boron carbide (B4C) to granule powder. Using the granulated granule powder, an ingot of a molded body is produced by hydrostatic molding, and then multiple molded bodies that will become plate-shaped members 200 are produced from the ingot of the molded body. The multiple molded bodies are fired to become multiple sintered bodies, and then a groove corresponding to the channel 21 is machined into a specific sintered body. The base 20 is produced by joining a specific sintered body to another sintered body, so that the groove corresponding to the channel 21 machined into the specific sintered body is covered by another sintered body. At this time, instead of joining sintered bodies together, a sintered body of the base 20 having the channel 21 may be produced by stacking and firing calcined bodies that have been fired at a temperature lower than the sintering temperature. Also, if necessary, the final shape processing may be performed after joining the specific sintered body to another sintered body. Note that the manufacturing method of the base 20 is not limited to this. For example, a slurry for green sheets containing silicon carbide powder is formed into a sheet using a casting device, and the resulting molded product is dried to produce multiple green sheets. Next, grooves corresponding to the flow channels 21 are machined into a specific green sheet among the multiple green sheets. Then, a base 20 is produced by firing a laminate of green sheets, which is made by stacking multiple green sheets including the specific green sheet with the machined grooves.

[0040] As shown in Figure 3, in this embodiment, the base 20 has a flow path 21 through which the refrigerant flows, which is formed relatively far from the first main surface 20a to which the base material 10 is joined. As a result, in this embodiment, the temperature distribution on the first main surface 20a can be made relatively small, and therefore the temperature distribution on the mounting surface 11 of the base material 10 can be made relatively small.

[0041] Figure 4 is a schematic diagram illustrating the heat transfer path in the comparative example base. Figure 4 shows a schematic cross-section of a base S20 which is a comparative example of the base 20 of this embodiment. The comparative example base S20 comprises a plate-shaped member S200 having a first main surface S20a on which a substrate 10 on which a substrate Sb is placed is arranged, and a second main surface S20b formed on the opposite side of the first main surface S20a, and a plurality of flow channels S21 arranged inside the plate-shaped member S200 through which a refrigerant flows. Figure 4 shows the relationship of the heat transfer path between one flow channel S21 and each point on the first main surface S20a of the plate-shaped member S200 in a cross-section of the base S20.

[0042] Here, we will explain the positional relationship between each point on the first main surface S21a shown in Figure 4 and the flow path S21. In Figure 4, seven points Pt1, Pt2, Pt3, Pt4, Pt5, Pt6, and Pt7 are set as points on the first main surface S21a. Point Pt1 is a point on the center CS21 of the flow path S21, point Pt2 is a point on one corner CS211 of the flow path S21, and point Pt3 is a point on the other corner CS212 of the flow path S21. Therefore, each of points Pt1, Pt2, and Pt3 can be said to be located directly above the flow path S21 (in the positive direction of the z axis).

[0043] Point Pt4 is located at a distance of 1 / 4 of the width W of the flow path S21, in the opposite direction from point Pt1 from point Pt2. Point Pt5 is located at a distance of 1 / 4 of the width W of the flow path S21, in the opposite direction from point Pt1 from point Pt3. Point Pt6 is located at a distance of 1 / 2 of the width W of the flow path S21, in the opposite direction from point Pt1 from point Pt2. Point Pt7 is located at a distance of 1 / 2 of the width W of the flow path S21, in the opposite direction from point Pt1 from point Pt3. Thus, points Pt4, Pt5, Pt6, and Pt7 are all points that are not directly above the flow path S21.

[0044] In Figure 4, the heat transfer paths T1, T2, T3, T4, T5, T6, and T7 between points Pt1, Pt2, Pt3, Pt4, Pt5, Pt6, and Pt7 on the first main surface S21a and the outline S210 of the flow path S21 are shown by white arrows. The lengths of each heat transfer path T1, T2, T3, T4, T5, T6, and T7 are also the shortest distances between points Pt1, Pt2, Pt3, Pt4, Pt5, Pt6, and Pt7 on the first main surface S20a and the outline S210 of the flow path S21. In the comparative example base S20 shown in Figure 4, the lengths of the longest heat transfer paths T6 and T7 between points Pt1, Pt2, Pt3, Pt4, Pt5, Pt6, and Pt7 on the first main surface S21a and the flow path S21 are 2.2 times the length of the shortest heat transfer path T1.

[0045] Figure 5 is a schematic diagram illustrating the heat transfer path in the base 20 of this embodiment. Figure 5 is a schematic cross-section of the base 20 of this embodiment, showing the relationship between the heat transfer path between one flow path 21 and each point on the first main surface 20a of the plate-shaped member 200 in the cross-section of the base 20. In Figure 5, the position of the flow path S21 in the comparative example base S20 shown in Figure 4 is indicated by a dashed line. As shown in Figure 5, the position of the flow path 21 in the base 20 of this embodiment is located on the second main surface 20b side than the flow path S21 in the comparative example base S20.

[0046] In Figure 5, similar to Figure 4, seven points Pt1, Pt2, Pt3, Pt4, Pt5, Pt6, and Pt7 are set as points on the first main surface 20a with respect to the center C21 of the flow path 21 and the corners C211 and C212 of the flow path 21. The lengths of the heat transfer paths T1, T2, T3, T4, T5, T6, and T7 between each of the points Pt1, Pt2, Pt3, Pt4, Pt5, Pt6, and Pt7 on the first main surface 20a shown in Figure 5 and the outline 210 of the flow path 21 are longer than the lengths of the heat transfer paths T1, T2, T3, T4, T5, T6, and T7 shown in Figure 4. Furthermore, in the base 20 of this embodiment shown in Figure 5, the lengths of the longest heat transfer paths T6 and T7 among points Pt1, Pt2, Pt3, Pt4, Pt5, Pt6, and Pt7 on the first main surface 20a are 1.6 times the length of the shortest heat transfer path T1. In other words, when comparing the ratio of the lengths of the longest heat transfer paths T6 and T7 to the length of the shortest heat transfer path T1, the base 20 of this embodiment is smaller than the base S20 of the comparative example.

[0047] Generally, the temperature difference between two points is determined by the product of the amount of heat transferred between the two points and the distance of the heat transfer path between the two points, with respect to the thermal conductivity of the materials present between the two points. In other words, the temperature difference between two points changes depending on the distance of the heat transfer path between the two points. Therefore, if the temperature on the flow path side is determined by the temperature of the refrigerant flowing through the flow path, the temperature distribution on the first main surface of the base will be determined by the magnitude of the ratio of the heat transfer path distances between the flow path and each of the multiple points on the first main surface. Specifically, if the ratio of the heat transfer path distances is small, the change in the heat transfer path distance between the two points will be small, and therefore the temperature distribution on the first main surface of the base will be small. If the ratio of the heat transfer path distances is large, the change in the heat transfer path distance between the two points will be large, and therefore the temperature distribution on the first main surface of the base will be large.

[0048] In the base 20 of this embodiment shown in Figure 5, the length of the longest heat transfer paths T6 and T7 is 1.6 times the length of the shortest heat transfer path T1, while in the comparative example base S20 shown in Figure 4, the length of the longest heat transfer paths T6 and T7 is 2.2 times the length of the shortest heat transfer path T1. Therefore, the temperature distribution at the seven points Pt1, Pt2, Pt3, Pt4, Pt5, Pt6, and Pt7 is smaller in the base 20 of this embodiment than in the comparative example base S20. Consequently, in the base 20 of this embodiment, the temperature distribution on the first main surface 20a is smaller, and therefore the temperature distribution on the mounting surface 11 of the substrate 10 joined to the base 20 is also smaller.

[0049] In this embodiment, the holding device 1 satisfies equation (4) when the distance between the first main surface 20a and the flow path 21 in the thickness direction cross-section of the plate-shaped member 200 is D1 and the thickness of the base material 10 is D2. As a result, the ratio of the distance of the heat transfer path in the portion of the base material 10 that is located away from the flow path 21 to the distance of the heat transfer path in the portion located directly above the flow path 21 on the mounting surface 11 becomes even smaller. Therefore, the temperature distribution due to differences in the distance of the heat transfer paths can be further reduced, and thus the temperature distribution on the mounting surface 11 can be further improved. D1 ≤ D2 ···(4)

[0050] The holding device 1 satisfies equation (5) when, in the cross-section of the plate-shaped member 200 in the thickness direction, G is the distance between adjacent flow channels 21 among the multiple flow channels 21, and D2 is the thickness of the base material 10. That is, because the distance G between adjacent flow channels 21 is small relative to the thickness D2 of the base material 10, the cooling effect of the refrigerant flowing through the flow channels 21 is more easily transmitted evenly across the entire mounting surface 11. This further improves the temperature distribution on the mounting surface 11. G ≤ D² ···(5)

[0051] As described above, according to the base 20 of this embodiment, the cross section of the plate-shaped member 200 on which the flow path 21 is formed is divided equally into three parts in the thickness direction, and the region on the first main surface 20a side is designated as the first region R201. Then the total cross-sectional area of ​​the flow path 21 included in the first region R201 is 0% to 30% of the total cross-sectional area of ​​the flow path 21. In other words, the distance between the first main surface 20a on which the base material 10 is placed and the flow path 21 of the plate-shaped member 200 is relatively long. As a result, the ratio of the distance of the heat transfer path in the portion of the first main surface 20a that is not directly above the flow path 21 to the distance of the heat transfer path in the portion located directly above the flow path 21 is relatively small, so that the temperature distribution due to differences in the distance of the heat transfer path can be reduced. Therefore, the temperature distribution on the first main surface 20a can be improved.

[0052] Furthermore, according to the base 20 of this embodiment, when the cross-section of the plate-shaped member 200 on which the flow path 21 is formed is divided equally into three parts in the thickness direction, the total cross-sectional area of ​​the flow path 21 included in the second region R202 is 0% to 85% of the total cross-sectional area of ​​the flow path 21, and the total cross-sectional area of ​​the flow path 21 included in the third region R203 is 15% to 100% of the total cross-sectional area of ​​the flow path 21. In other words, the majority of the flow path 21 is formed mainly on the second main surface 20b side of the plate-shaped member 200. As a result, since much of the refrigerant flows at a position relatively farther away from the first main surface 20a, the ratio of the distance of the heat transfer path in the part of the first main surface 20a that is farther away from the flow path 21 to the distance of the heat transfer path in the part located directly above the flow path 21 becomes even smaller. Therefore, the temperature distribution due to differences in the distance of the heat transfer path can be further reduced, and the temperature distribution on the first main surface 20a can be further improved.

[0053] Furthermore, according to the base 20 of this embodiment, since the base 20 satisfies equation (2), the distance D1 between the first main surface and the flow path is greater than the distance G between adjacent flow paths. As a result, the cooling effect of the refrigerant flowing through the flow path 21 is more easily and evenly distributed across the entire first main surface 20a, thereby further improving the temperature distribution on the first main surface 20a.

[0054] Furthermore, according to the base 20 of this embodiment, in the plate-shaped member 200, the average H of the depths of adjacent flow channels 21 relative to the thickness D of the plate-shaped member 200 is 0.1 or more, which allows for a certain degree of cooling effect by the refrigerant flowing through the flow channels 21, and is less than 0.6, which allows for the maintenance of structural strength. This makes it possible to achieve both the strength of the plate-shaped member 200 on which the substrate 10 on which the substrate Sb is placed is arranged, and the cooling effect by the refrigerant.

[0055] Furthermore, according to the base 20 of this embodiment, the base 20 is made of ceramics. This improves the corrosion resistance of the base 20 to refrigerants.

[0056] Furthermore, according to the holding device 1 of this embodiment, the holding device 1 is equipped with a base 20 having a relatively small temperature distribution on the first main surface 20a. This makes it possible to reduce the temperature distribution on the mounting surface 11 of the substrate 10 that is placed on the first main surface 20a of the base 20.

[0057] Furthermore, according to the holding device 1 of this embodiment, the thickness D2 of the base material 10 is greater than or equal to the distance D1 between the first main surface 20a of the base 20 and the flow path 21. Therefore, the ratio of the distance of the heat transfer path in the portion of the mounting surface 11 that is not directly above the flow path 21 to the distance of the heat transfer path in the portion directly above the flow path 21 is relatively small. As a result, the temperature distribution due to differences in the distance of the heat transfer path can be reduced, and thus the temperature distribution on the mounting surface 11 can be improved.

[0058] Furthermore, according to the holding device 1 of this embodiment, since the distance G between adjacent flow channels 21 is small relative to the thickness D2 of the base material 10, the cooling effect of the refrigerant flowing through the flow channels 21 is easily transmitted evenly across the entire mounting surface 11. This further improves the temperature distribution on the mounting surface 11.

[0059] <Second Embodiment> Figure 6 is an enlarged cross-sectional view of the holding device 2 of the second embodiment. Compared with the holding device 1 of the first embodiment (Figure 3), the holding device 2 of the second embodiment has a different position of the flow path inside the base.

[0060] The holding device 2 of this embodiment comprises a base material 10, a base 20, and a joint 30. The base 20 of the holding device 2 comprises a plate-shaped member 200, a flow path 22 through which a refrigerant flows, and an opening 20c.

[0061] The flow channels 22 are formed to appear in multiple locations in the cross-section of the base 20 shown in Figure 6. In this embodiment, in a cross-section of the plate-shaped member 200 in the thickness direction (z-axis direction) including the central axis C200 of the plate-shaped member 200, the flow channels 22 are arranged in multiple locations along the first main surface 20a and the second main surface 20b, respectively.

[0062] In the base 20 of this embodiment, the total cross-sectional area of ​​the flow channels 22 included in the first region R201 is 0% of the total cross-sectional area of ​​the flow channels 22, as shown in Figure 6, and the flow channels 22 are not formed to be included in the first region R201. On the other hand, the total cross-sectional area of ​​the portion 222 of the flow channels 22 included in the second region R202 is 50% of the total cross-sectional area of ​​the flow channels 22, and the total cross-sectional area of ​​the portion 223 of the flow channels 22 included in the third region R203 is 50% of the total cross-sectional area of ​​the flow channels 22. In other words, the flow channels 22 of the base 20 of this embodiment are located on the second main surface 20b side than the flow channels 21 provided in the base 20 of the first embodiment.

[0063] As described above, according to the base 20 of this embodiment, the total cross-sectional area of ​​the flow channels 22 included in the first region R201 is 0% of the total cross-sectional area of ​​the flow channels 22, the total cross-sectional area of ​​the flow channels 22 included in the second region R202 is 50% of the total cross-sectional area of ​​the flow channels 22, and the total cross-sectional area of ​​the flow channels 22 included in the third region R203 is 50% of the total cross-sectional area of ​​the flow channels 22. In other words, the plate-shaped member 200 has a relatively long distance between the first main surface 20a on which the base material 10 is placed and the flow channels 22. As a result, the ratio of the distance of the heat transfer path in the portion of the first main surface 20a that is located away from the flow channels 22 to the distance of the heat transfer path in the portion located directly above the flow channels 22 is relatively small, so that the temperature distribution due to differences in the distance of the heat transfer paths can be reduced. Therefore, the temperature distribution on the first main surface 20a can be further improved.

[0064] <Third Embodiment> Figure 7 is an enlarged cross-sectional view of the holding device 3 of the second embodiment. Compared to the holding device 1 of the first embodiment (Figure 3), the holding device 3 of the third embodiment has a different position of the flow path inside the base.

[0065] The holding device 3 of this embodiment comprises a base material 10, a base 20, and a joint 30. The base 20 of the holding device 3 comprises a plate-shaped member 200, a flow path 23 through which a refrigerant flows, and an opening 20c.

[0066] Multiple flow channels 23 are formed to appear in the cross-section of the base 20 shown in Figure 7. In this embodiment, multiple flow channels 23 are arranged in the cross-section of the plate-shaped member 200 in the thickness direction (z-axis direction), including the central axis C200 of the plate-shaped member 200, so as to be aligned along the first main surface 20a and the second main surface 20b, respectively.

[0067] In the base 20 of this embodiment, the total cross-sectional area of ​​the flow channels 23 included in the first region R201 is 0% of the total cross-sectional area of ​​the flow channels 23, and the total cross-sectional area of ​​the flow channels 23 included in the second region R202 is also 0% of the total cross-sectional area of ​​the flow channels 23. In other words, the flow channels 23 are not formed to be included in the first region R201 and the second region R202, respectively.

[0068] In the base 20 of this embodiment, the total cross-sectional area of ​​the portion 233 of the flow path 23 included in the third region R203 is 100% of the total cross-sectional area of ​​the flow path 23. That is, the flow path 23 of the base 20 of this embodiment is positioned further toward the second main surface 20b than the flow path 22 of the base 20 of the second embodiment.

[0069] As described above, according to the base 20 of this embodiment, the total cross-sectional area of ​​the flow channels 23 included in the first region R201 is 0% of the total cross-sectional area of ​​the flow channels 23, the total cross-sectional area of ​​the flow channels 23 included in the second region R202 is 0% of the total cross-sectional area of ​​the flow channels 23, and the total cross-sectional area of ​​the flow channels 23 included in the third region R203 is 100% of the total cross-sectional area of ​​the flow channels 23. In other words, the plate-shaped member 200 has a relatively long distance between the first main surface 20a on which the base material 10 is placed and the flow channels 23. As a result, the ratio of the distance of the heat transfer path in the portion of the first main surface 20a that is located away from the flow channels 23 to the distance of the heat transfer path in the portion located directly above the flow channels 23 is relatively small, so that the temperature distribution due to differences in the distance of the heat transfer paths can be reduced. Therefore, the temperature distribution on the first main surface 20a can be further improved.

[0070] <Fourth Embodiment> Figure 8 is an enlarged cross-sectional view of the holding device 4 of the fourth embodiment. The holding device 4 of the fourth embodiment differs from the holding device 1 of the first embodiment (Figure 3) in that the base has a heat transfer suppressing member positioned between the flow path and the first main surface.

[0071] The holding device 4 of this embodiment comprises a base material 10, a base 20, and a joint 30. The base 20 of the holding device 4 comprises a plate-shaped member 200, a flow path 21 through which a refrigerant flows, an opening 20c, and a plurality of heat transfer suppression parts 24.

[0072] The heat transfer suppression section 24 is positioned on the base 20 between the flow path 21 and the first main surface 20a, and is made of a material with a thermal conductivity lower than that of the material forming the plate-shaped member 200. In this embodiment, the heat transfer suppression section 24 is positioned in the positive z-axis direction of the multiple flow paths 21, that is, directly above the multiple flow paths 21. In this embodiment, the heat transfer suppression section 24 is housed in a groove 200a formed in the first main surface 20a of the plate-shaped member 200. The size of the heat transfer suppression section 24 in this embodiment is greater than or equal to the size of the flow path 21 when the holding device 4 is viewed from the z-axis direction.

[0073] Here, if we define point Pt41 as the point located directly above the flow path 21 (in the positive z-direction), and point Pt42 as the point located away from directly above the flow path S21, then point Pt41 is located closer to the flow path 21 than point Pt42. Therefore, in terms of the difference in heat transfer path distance, heat is transferred more easily between point Pt41 and the flow path 21 than between point Pt42 and the flow path 21. However, since the holding device 4 of this embodiment is equipped with a heat transfer suppression section 24 with relatively low thermal conductivity between point Pt41 and the flow path 21, heat is transferred relatively less easily between point Pt41 and the flow path 21. As a result, the difference between the amount of heat transferred between point Pt41 and the flow path 21 and the amount of heat transferred between point Pt42 and the flow path 21 becomes less significant.

[0074] As described above, with respect to the base 20 of this embodiment, the distance between the first main surface 20a on which the base material 10 is placed and the flow path 21 of the plate-shaped member 200 is relatively long. As a result, the ratio of the distance of the heat transfer path in the portion of the first main surface 20a that is located away from the flow path 21 to the distance of the heat transfer path in the portion located directly above the flow path 21 is relatively small, and thus the temperature distribution due to differences in the distance of the heat transfer path can be reduced. Therefore, the temperature distribution on the first main surface 20a can be further improved.

[0075] Furthermore, according to the base 20 of this embodiment, the cooling effect of the refrigerant flowing through the flow path 21 is less likely to be transmitted to the portion of the first main surface 20a located directly above the flow path 21. As a result, the temperature of the portion of the first main surface 20a located directly above the flow path 21, which is easily cooled by the refrigerant flowing through the flow path 21, tends to be closer to the ambient temperature. Therefore, the temperature distribution on the first main surface 20a can be further improved.

[0076] <Fifth Embodiment> Figure 9 is an enlarged cross-sectional view of the holding device 5 of the fifth embodiment. The holding device 5 of the fifth embodiment differs from the holding device 1 of the first embodiment (Figure 3) in the configuration of its base.

[0077] The holding device 5 of this embodiment comprises a base material 10, a base 20, and a joint 30. The base 20 of the holding device 5 comprises a plate-shaped portion 250, a flow path 21 through which a refrigerant flows, and an opening 20c.

[0078] The plate-like portion 250 comprises a first base 251 and a second base 252. In this embodiment, the first base 251 and the second base 252 are stacked along the thickness direction (z-axis direction) of the plate-like portion 25. The first base 251 has a first main surface 25a of the plate-like portion 25. The thermal conductivity of the material forming the first base 251 is greater than the thermal conductivity of the material forming the second base 252. The second base 252 has a second main surface 25b of the plate-like portion 25. The second base 252 has a plurality of grooves 253 formed on the side facing the first base 251.

[0079] The plate-like portion 250 is formed by joining the first base 251 and the second base 252. At this time, the multiple grooves 253 formed in the second base 252 become flow channels 21 when the positive side in the z-axis direction is blocked by the first base 251.

[0080] As described above, with the base 20 of this embodiment, the distance between the first main surface 25a on which the base material 10 is placed and the flow path 21 is relatively long. As a result, the ratio of the distance of the heat transfer path in the portion of the first main surface 25a that is located away from the flow path 21 to the distance of the heat transfer path in the portion located directly above the flow path 21 is relatively small, so that the temperature distribution due to differences in the distance of the heat transfer path can be reduced. Therefore, the temperature distribution on the first main surface 25a can be further improved.

[0081] Furthermore, according to the base 20 of this embodiment, the plate-shaped portion 250 has a first base 251 having a first main surface 25a and a second base 252 having a second main surface 25b. A flow channel 21 is formed in the second base 252, and the thermal conductivity of the material forming the first base 251 is greater than that of the material forming the second base 252. As a result, the thermal resistance between the first main surface 25a and the flow channel 21 is relatively small, and the temperature distribution due to differences in the distance of the heat transfer path can be further reduced. Therefore, the temperature distribution on the first main surface 25a can be further improved.

[0082] <Sixth Embodiment> Figure 10 is an enlarged cross-sectional view of the holding device 6 of the sixth embodiment. Compared with the holding device 1 of the first embodiment (Figure 3), the thickness of the base material is different from the thickness of the base in the holding device 6 of the sixth embodiment.

[0083] The holding device 6 of this embodiment comprises a base material 40, a base 20, and a joint 30. The base material 40 is a disc-shaped member made of ceramics and has a first main surface 40a and a second main surface 40b. The base material 40 has a mounting surface 41 on the first main surface 40a on which a substrate Sb is placed. The base material 40 has a plurality of protrusions 40c on the first main surface 40a that form the mounting surface 41. The base material 40 incorporates a chuck electrode 42 made of a conductive material. The chuck electrode 42 is connected to an external power source via an electrode terminal (not shown), and when power is supplied from the external power source, it generates an electrostatic attractive force capable of adsorbing and holding the substrate Sb on the mounting surface 41. In addition to the chuck electrode 42, the base material 40 may also incorporate a high-frequency electrode for plasma or a heater electrode. These electrodes may also be incorporated into the base 20.

[0084] In the holding device 6, if we consider the distance between the first main surface 20a and the flow path 21 in the cross-section of the plate-shaped member 200 of the base 20 in the thickness direction (z-axis direction), and the thickness of the base material 40 as D1, then equation (4) is satisfied. As a result, the ratio of the distance of the heat transfer path in the portion of the base material 40 that is located away from the flow path 21 to the distance of the heat transfer path in the portion located directly above the flow path 21 on the mounting surface 41 of the base material 40 becomes relatively small. Therefore, the temperature distribution due to differences in the distance of the heat transfer paths can be made relatively small, and thus the temperature distribution on the mounting surface 41 can be improved. D1 ≤ D2 ···(4)

[0085] As described above, with respect to the base 20 of this embodiment, the distance between the first main surface 20a on which the base material 10 is placed and the flow path 21 of the plate-shaped member 200 is relatively long. As a result, the ratio of the distance of the heat transfer path in the portion of the first main surface 20a that is located away from the flow path 21 to the distance of the heat transfer path in the portion located directly above the flow path 21 is relatively small, and thus the temperature distribution due to differences in the distance of the heat transfer path can be reduced. Therefore, the temperature distribution on the first main surface 20a can be further improved.

[0086] Furthermore, according to the holding device 6 of this embodiment, the thickness D2 of the base material 40 is greater than or equal to the distance D1 between the first main surface 20a on the base 20 and the flow path 21. Therefore, the ratio of the distance of the heat transfer path in the portion of the mounting surface 41 that is not directly above the flow path 21 to the distance of the heat transfer path in the portion directly above the flow path 21 is relatively small. As a result, the temperature distribution due to differences in the distance of the heat transfer path can be reduced, and thus the temperature distribution on the mounting surface 41 can be improved.

[0087] <Seventh Embodiment> Figure 11 is a cross-sectional view of the holding device 7 of the seventh embodiment. The holding device 7 of the seventh embodiment has a different base shape compared to the holding device 1 of the first embodiment (Figure 3).

[0088] The holding device 7 of this embodiment comprises a base material 10, a base 50, and a joint portion 30. The base 50 of the holding device 7 comprises a plate-shaped member 500, a flow path 21 through which a refrigerant flows, an opening 20c, and a recessed portion 51, all located inside the plate-shaped member 500.

[0089] The recessed portion 51 is formed on the second main surface 50b of the plate-shaped member 500, which is located on the negative side in the z-axis direction of the plate-shaped member 500, of the pair of main surfaces 50a and 50b of the plate-shaped member 500. The recessed portion 51 is fitted into a fixing projection provided on the holding device 7 when the holding device 7 is fixed to a device that uses the holding device 7.

[0090] Figure 12 is an enlarged view of part B of Figure 11, and is an enlarged cross-sectional view of a part of the cross-sectional view of the holding device 7 shown in Figure 11. In the base 50 of the holding device 7, of the dividing lines L0, L1, L2, and L3 that evenly divide the cross-section of the plate-shaped member 500 into three parts in the thickness direction, dividing line L0 is an imaginary line passing through the first main surface 50a of the plate-shaped member 500, and dividing line L3 is an imaginary line passing through the bottom surface 51a of the recessed part 51. Therefore, the first region R501 in the base 50 is the region sandwiched between dividing line L0 and dividing line L1, the second region R502 is the region sandwiched between dividing line L1 and dividing line L2, and the third region R503 is the region sandwiched between dividing line L2 and dividing line L3. In the base 50 of the holding device 7, the total cross-sectional area of ​​the flow channels 21 included in the first region R501 is between 0% and 30% of the total cross-sectional area of ​​the flow channels 21. Specifically, the total cross-sectional area of ​​the flow channels 21 included in the first region R501 is 5% of the total cross-sectional area of ​​the flow channels 21.

[0091] As described above, with the base 50 of this embodiment, the distance between the first main surface 50a on which the base material 10 is placed and the flow path 21 of the plate-shaped member 500 is relatively long. As a result, the ratio of the distance of the heat transfer path in the portion of the first main surface 50a that is located away from the flow path 21 to the distance of the heat transfer path in the portion located directly above the flow path 21 is relatively small, so that the temperature distribution due to differences in the distance of the heat transfer path can be reduced. Therefore, the temperature distribution on the first main surface 50a can be further improved.

[0092] <Eighth Embodiment> Figure 13 is an enlarged cross-sectional view of the holding device 8 of the eighth embodiment. The holding device 8 of the eighth embodiment has a different cross-sectional shape of the flow path compared to the holding device 1 of the first embodiment (Figure 3).

[0093] The holding device 8 of this embodiment comprises a base material 10, a base 20, and a joint 30. The base 20 of the holding device 8 comprises a plate-shaped member 200, a flow path 28 through which a refrigerant flows, and an opening 20c.

[0094] Multiple flow channels 28 are formed to appear in the cross-section of the base 20 shown in Figure 13. In this embodiment, multiple flow channels 28 are arranged in the cross-section of the plate-shaped member 200 in the thickness direction (z-axis direction), including the central axis C200 of the plate-shaped member 200, so as to be aligned along the first main surface 20a and the second main surface 20b, respectively.

[0095] Each of the multiple flow channels 28 in this embodiment has a trapezoidal shape in the cross-section in the thickness direction of the plate-like member 200, as shown in Figure 13. Specifically, the cross-sectional shape of the flow channel 28 is formed such that the width decreases as it moves in the positive z-axis direction.

[0096] In this embodiment, the base 20, in a cross-section of the plate-shaped member 200 in the thickness direction including the central axis C200 of the plate-shaped member 200, has a total cross-sectional area of ​​portion 281 of the flow channels 28 included in the first region R201 that is between 0% and 30% of the total cross-sectional area of ​​the flow channels 28. Specifically, the total cross-sectional area of ​​the flow channels 28 included in the first region R201 is 6% of the total cross-sectional area of ​​the flow channels 28.

[0097] In this embodiment, the base 20, in a cross-section of the plate-shaped member 200 in the thickness direction including the central axis C200 of the plate-shaped member 200, has a total cross-sectional area of ​​portion 282 of the flow channel 28 included in the second region R202 that is between 0% and 85% of the total cross-sectional area of ​​the flow channel 28. The total cross-sectional area of ​​portion 283 of the flow channel 28 included in the third region R203 is between 15% and 100% of the total cross-sectional area of ​​the flow channel 28. Specifically, the total cross-sectional area of ​​the flow channel 28 included in the second region R202 is 52% of the total cross-sectional area of ​​the flow channel 28, and the total cross-sectional area of ​​the flow channel 28 included in the third region R203 is 42% of the total cross-sectional area of ​​the flow channel 28.

[0098] As described above, with respect to the base 20 of this embodiment, the distance between the first main surface 20a on which the base material 10 is placed and the flow path 28 of the plate-shaped member 200 is relatively long. As a result, the ratio of the distance of the heat transfer path in the portion of the first main surface 20a that is located away from the flow path 28 to the distance of the heat transfer path in the portion located directly above the flow path 28 is relatively small, so that the temperature distribution due to differences in the distance of the heat transfer path can be reduced. Therefore, the temperature distribution on the first main surface 20a can be further improved.

[0099] <Modified form of this embodiment> The present invention is not limited to the embodiments described above, and can be implemented in various forms without departing from its spirit, for example, the following modifications are also possible.

[0100] [Example 1] In the above-described embodiment, the holding device is an electrostatic chuck that attracts and holds the substrate Sb by electrostatic attraction. The technical field to which the holding device is applied is not limited to this. The holding device of the above-described embodiment is also applicable to technical fields where it is necessary to hold an object to be held, including the substrate Sb.

[0101] [Differentiation 2] In the first embodiment, the total cross-sectional area of ​​the channels 21 included in the first region R201 of the base 20 was assumed to be 11% of the total cross-sectional area of ​​the channels 21. In the second embodiment, the total cross-sectional area of ​​the channels 22 included in the first region R201 of the base 20 was assumed to be 0% of the total cross-sectional area of ​​the channels 22. The ratio of the total cross-sectional area of ​​the channels included in the first region to the total cross-sectional area of ​​the channels is not limited to this. The total cross-sectional area of ​​the channels included in the first region may be 0% or more and 30% or less of the total cross-sectional area of ​​the channels.

[0102] Figure 14 is an enlarged cross-sectional view of a modified example of the holding device 1 of the first embodiment. In the base 20 of the holding device 1 shown in Figure 14, the cross-sectional area A211 of portion 211 of the flow path 21 is 30% of the cross-sectional area A21 of the flow path 21. Even with such a flow path 21, the plate-shaped member 200 has a relatively long distance between the first main surface 20a on which the base material 10 is placed and the flow path 21. Therefore, the ratio of the distance of the heat transfer path in the portion of the first main surface 20a that is not directly above the flow path 21 to the distance of the heat transfer path in the portion located directly above the flow path 21 is relatively small. Consequently, the temperature distribution due to differences in the distance of the heat transfer path can be reduced, and the temperature distribution on the first main surface 20a can be improved.

[0103] [Difference 3] In the first embodiment, the total cross-sectional area of ​​the flow channels 21 included in the second region R202 on the base 20 is 57% of the total cross-sectional area of ​​the flow channels 21, and in the third embodiment, the total cross-sectional area of ​​the flow channels 23 included in the second region R202 on the base 20 is 0% of the total cross-sectional area of ​​the flow channels 23. The ratio of the total cross-sectional area of ​​the flow channels included in the second region to the total cross-sectional area of ​​the flow channels is not limited to this and may be 57% or more. It is desirable that the total cross-sectional area of ​​the flow channels included in the second region be 0% or more and 85% or less of the total cross-sectional area of ​​the flow channels. As a result, since much of the refrigerant flows at a position relatively far from the first main surface, the ratio of the distance of the heat transfer path in the part of the first main surface that is far from the flow channels to the distance of the heat transfer path in the part that is directly above the flow channels becomes even smaller, and thus the temperature distribution on the first main surface can be further improved.

[0104] [Differentiation Example 4] In the first embodiment, the total cross-sectional area of ​​the flow channels 21 included in the third region R203 on the base 20 is 32% of the total cross-sectional area of ​​the flow channels 21, and in the third embodiment, the total cross-sectional area of ​​the flow channels 23 included in the third region R203 on the base 20 is 100% of the total cross-sectional area of ​​the flow channels 23. The ratio of the total cross-sectional area of ​​the flow channels included in the third region to the total cross-sectional area of ​​the flow channels is not limited to this and may be 32% or less. It is desirable that the total cross-sectional area of ​​the flow channels included in the third region be 15% or more and 100% or less of the total cross-sectional area of ​​the flow channels. As a result, since much of the refrigerant flows at a position relatively far from the first main surface, the ratio of the distance of the heat transfer path in the part of the first main surface that is far from the flow channels to the distance of the heat transfer path in the part that is directly above the flow channels becomes even smaller, and thus the temperature distribution on the first main surface can be further improved.

[0105] [Differentiation Example 4] In the above embodiment, the base is assumed to satisfy equation (1) in a cross-section in the thickness direction of the plate-like member, where G is the distance between adjacent channels among the multiple channels, and W is the average width of each adjacent channel. Equation (1) does not have to be satisfied.

[0106] [Difference 5] In the above embodiment, the base is assumed to satisfy the following equation (2) in a cross-section in the thickness direction of the plate-like member, where G is the distance between adjacent channels among the multiple channels, and D1 is the distance between the first main surface and the channel. Equation (2) does not have to be satisfied.

[0107] [Modification 6] In the above embodiment, the base was assumed to satisfy equation (3) when, in the cross-section in the thickness direction of the plate-shaped member, H is the average depth of each adjacent flow path and D is the thickness of the plate-shaped member. Equation (3) does not have to be satisfied.

[0108] [Difference 7] In the above embodiment, the holding device is assumed to satisfy equation (4) in the cross-section of the plate-shaped member in the thickness direction, where D1 is the distance between the first main surface and the flow path and D2 is the thickness of the base material. Equation (4) does not have to be satisfied.

[0109] [Differentiation 8] In the above embodiment, the holding device is assumed to satisfy equation (5) in a cross-section in the thickness direction of the plate-shaped member, where G is the distance between adjacent channels among the multiple channels and D2 is the thickness of the base material. Equation (5) does not have to be satisfied.

[0110] [Modification 9] In the fifth embodiment, the plate-like portion 250 of the base 20 comprises a first base 251 having a first main surface 25a of the plate-like portion 250, and a second base 252 having a plurality of grooves 253 formed therein, which become flow channels 21 when the positive side in the z-axis direction is blocked by the first base 251. The configuration of the plate-like portion is not limited to this.

[0111] Figure 15 is an enlarged cross-sectional view of a modified example of the holding device 5 of the fifth embodiment. In the holding device 5 shown in Figure 15, the plate-shaped portion 250 of the base 20 comprises a first base 251 and a second base 252. In the holding device 5 shown in Figure 15, the second base 252 has a groove 253 that independently serves as a flow path 21, and the first base 251 is positioned between the substrate 10 and the second base 252. Even with this type of holding device, the temperature distribution on the first main surface 25a can be further improved. Furthermore, in the holding device 5, the heat dissipation suppression member provided in the holding device 4 of the fourth embodiment may be positioned inside the first base 251, or between the first base 251 and the second base 252.

[0112] [Example 10] In the above-described embodiment, the holding device 1 comprises a base material 10, a base 20, and a joint portion 30, with the base material 10 having a built-in chuck electrode 12. The configuration of the holding device is not limited to this. It may also include a gas channel for supplying helium gas or the like to the mounting surface 11, and a temperature measuring member for measuring the temperature of the mounting surface 11.

[0113] The embodiments of this specification have been described above based on the embodiments and modifications described above. The embodiments described above are for the purpose of facilitating understanding of this specification and do not limit it. This specification may be modified and improved without departing from its spirit and the scope of the claims, and equivalents thereof are included in this specification. Furthermore, any technical features that are not described as essential in this specification may be deleted as appropriate.

[0114] <Application Example 1> A base used in a holding device, A plate-shaped member having a first main surface on which a base material on which an object to be held is placed is positioned, and a second main surface formed on the opposite side of the first main surface, The plate-shaped member is arranged inside the plate-shaped member and comprises a flow path through which a refrigerant flows, In a cross-section of the plate-like member in the thickness direction, including the central axis of the plate-like member, If the cross-section of the plate-like member is divided equally into three parts in the thickness direction, and the region on the first main surface side is designated as the first region, The sum of the cross-sectional areas of the channels included in the first region is characterized in that it is 0% or more and 30% or less of the sum of the cross-sectional areas of the channels. Base. <Application Example 2> The holding device described in Application Example 1, In the cross-section of the plate-like member in the thickness direction, If the cross-section of the plate-like member is divided equally into three parts in the thickness direction, and the region on the second main surface side is designated as the third region, and the region between the first region and the third region is designated as the second region, The sum of the cross-sectional areas of the channels included in the second region is 0% or more and 85% or less of the sum of the cross-sectional areas of the channels. The sum of the cross-sectional areas of the flow channels included in the third region is characterized in that it is 15% or more and 100% or less of the sum of the cross-sectional areas of the flow channels. Base. <Application Example 3> The base described in Application Example 1 or Application Example 2 further, The invention is characterized by comprising a heat transfer suppression portion disposed between the flow channel and the first main surface, and formed of a material having a thermal conductivity lower than that of the material forming the plate-shaped member, Base. <Application Example 4> A base described in any one of the examples from Application Example 1 to Application Example 3, In the cross-section of the plate-like member in the thickness direction, Multiple flow channels are arranged so as to be aligned along the width direction of the plate-shaped member. Let G be the distance between adjacent channels among the multiple channels. If we let W be the average width of each of the adjacent channels, A characteristic that satisfies equation (1): Base. 0.1 ≤ G / W ≤ 1 ···(1) <Application Example 5> A base described in any one of the examples from Application Example 1 to Application Example 4, In the cross-section of the plate-like member in the thickness direction, If the distance between the first main surface and the flow path is D1, The following characteristics satisfy equation (2): Base. G ≤ D1 ···(2) <Application Example 6> A base described in any one of the examples from Application Example 1 to Application Example 5, In the cross-section of the plate-like member in the thickness direction, Let H be the average depth of each of the adjacent channels. If the thickness of the plate-like member is D, The following characteristics satisfy equation (3): Base. 0.1 ≤ H / D < 0.6 ···(3) <Application Example 7> A base described in any one of the examples from Application Example 1 to Application Example 6, The plate-shaped member is A first base having the first main surface, A second base having the second main surface, the second base having the flow path formed therein, The thermal conductivity of the material forming the first base is greater than the thermal conductivity of the material forming the second base. Base. <Application Example 8> A base described in any one of the examples from Application Example 1 to Application Example 7, Characterized by being formed from ceramics, Base. <Application Example 9> A holding device, A base described in any one of the examples from Application Example 1 to Application Example 8, A base material to be joined to the first main surface, the base material having a mounting surface on which an object to be held is placed, is characterized by comprising: holding device. <Application Example 10> The holding device described in Application Example 9, In the cross-section of the plate-like member in the thickness direction, Let D1 be the distance between the first main surface and the flow path. If the thickness of the substrate is D2, The following are characterized by satisfying equation (4): holding device. D1 ≤ D2 ···(4) <Application Example 11> A holding device as described in Example 9 or Example 10, In the cross-section of the plate-like member in the thickness direction, Multiple flow channels are arranged so as to be aligned along the width direction of the plate-shaped member. Let G be the distance between adjacent channels among the multiple channels. If the thickness of the substrate is D2, A characteristic that satisfies equation (5), holding device. G ≤ D² ···(5) [Explanation of Symbols]

[0115] 1,2,3,4,5,6,7,8…holding device 20, 50… base 10,40…Base material 11… Mounting surface 20a, 50a... First main surface 20b, 50b... Second main surface 21, 22, 23, 28…flow channels 200,500…plate-shaped member 250...plate-like part 251...First base 252...Second base A21,A211,A212,A213…Cross-sectional area R201... First Domain R202...Second Domain R203... Third Domain Sb... circuit board

Claims

1. A base used in a holding device, A plate-shaped member having a first main surface on which a base material on which an object to be held is placed is positioned, and a second main surface formed on the opposite side of the first main surface, The plate-shaped member is arranged inside the aforementioned plate-shaped member and has a flow path through which the refrigerant flows, The system includes a heat transfer suppression section disposed between the flow path and the first main surface, which is made of a material having a lower thermal conductivity than the material forming the plate-shaped member, In a cross-section of the plate-like member in the thickness direction, including the central axis of the plate-like member, If the cross-section of the plate-like member is divided equally into three parts in the thickness direction, and the region on the first main surface side is designated as the first region, The sum of the cross-sectional areas of the channels included in the first region is characterized in that it is 0% or more and 30% or less of the sum of the cross-sectional areas of the channels. Base.

2. A holding device according to claim 1, In the cross-section of the plate-like member in the thickness direction, If the cross-section of the plate-like member is divided equally into three parts in the thickness direction, and the region on the second main surface side is designated as the third region, and the region between the first region and the third region is designated as the second region, The total cross-sectional area of ​​the flow channels included in the second region is 0% or more and 85% or less of the total cross-sectional area of ​​the flow channels. The sum of the cross-sectional areas of the flow channels included in the third region is characterized in that it is 15% or more and 100% or less of the sum of the cross-sectional areas of the flow channels. Base.

3. A base according to claim 1 or claim 2, In the cross-section of the plate-like member in the thickness direction, Multiple flow channels are arranged so as to be aligned along the width direction of the plate-shaped member. Let G be the distance between adjacent channels among the multiple channels. If we let W be the average width of each of the adjacent channels, A characteristic that satisfies formula (1): Base. 0.1 ≤ G / W ≤ 1 ... (1)

4. The base according to claim 3, In the cross-section of the plate-like member in the thickness direction, If the distance between the first main surface and the flow path is D1, A characteristic that satisfies formula (2): Base. G ≤ D1 ... (2)

5. The base according to claim 3, In the cross-section of the plate-like member in the thickness direction, Let H be the average depth of each of the adjacent channels. If the thickness of the plate-like member is D, A characteristic that satisfies equation (3): Base. 0.1≦H / D<0.6 (3)

6. A base according to claim 1 or claim 2, The aforementioned plate-shaped member is The first base having the first main surface, A second base having the second main surface, the second base having the flow path formed therein, The thermal conductivity of the material forming the first base is greater than the thermal conductivity of the material forming the second base. Base.

7. A base according to claim 1 or claim 2, Characterized by being formed from ceramics, Base.

8. A holding device, A base according to claim 1 or claim 2, A base material to be joined to the first main surface, the base material having a mounting surface on which an object to be held is placed, is characterized by comprising: holding device.

9. A holding device according to claim 8, In the cross-section of the plate-like member in the thickness direction, Let D1 be the distance between the first main surface and the flow path. If the thickness of the substrate is D2, A characteristic that satisfies equation (4): holding device. D1 ≤ D2 ... (4)

10. A holding device according to claim 8, In the cross-section of the plate-like member in the thickness direction, Multiple flow channels are arranged so as to be aligned along the width direction of the plate-shaped member. Let G be the distance between adjacent channels among the multiple channels. If the thickness of the substrate is D2, Characterized by satisfying equation (5), holding device. G ≤ D² ... (5)

11. A base used in a holding device, A plate-shaped member having a first main surface on which a base material on which an object to be held is placed is positioned, and a second main surface formed on the opposite side of the first main surface, The plate-shaped member is arranged inside the plate-shaped member and comprises a flow path through which a refrigerant flows, The aforementioned plate-shaped member is The first base having the first main surface, A second base having the second main surface, the second base having the flow path formed therein, The thermal conductivity of the material forming the first base is greater than the thermal conductivity of the material forming the second base. In a cross-section of the plate-like member in the thickness direction, including the central axis of the plate-like member, If the cross-section of the plate-like member is divided equally into three parts in the thickness direction, and the region on the first main surface side is designated as the first region, The sum of the cross-sectional areas of the channels included in the first region is characterized in that it is 0% or more and 30% or less of the sum of the cross-sectional areas of the channels. Base.

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