Holding device

Abstract

To provide a holding device capable of improving heat removal performance of a plate member.SOLUTION: An electrostatic chuck 1 includes a plate member 10 including a holding surface 11 and a lower surface 12 provided on an opposite side of the holding surface 11, a base member 20 including an upper surface 21 and a lower surface 22 provided on the opposite side of the upper surface 21, and a bonding layer 30 disposed between the lower surface 12 and the upper surface 21 and bonding the plate member 10 and the base member 20, and holds a semiconductor wafer W on the holding surface 11 of the plate member 10, and the base member 20 includes a refrigerant flow path 23 through which refrigerant flows, and at least one of the plate member 10 and the bonding layer 30 includes a refrigerant channel 13 (or 33) through which a refrigerant flows.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] In the holding device, in order to cool the object to be held to a predetermined temperature, for example, a metal base (base member) is bonded to a ceramic body (plate-shaped member) that holds the object, i.e., a semiconductor wafer, via a silicone resin (bonding layer), and a refrigerant flow path through which a refrigerant flows is provided in the metal base. Then, by cooling the metal base with the refrigerant flowing through the refrigerant flow path, the temperature of the semiconductor wafer held by the ceramic body is lowered to the predetermined temperature (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-310832 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, in semiconductor wafer processing, there have been an increasing number of cases where the input energy to the semiconductor wafer is increased, for example, due to deeper etching depth, and the heat input to the semiconductor wafer is also increasing. Therefore, simply providing a coolant flow path in the base member and flowing the coolant, as in conventional devices, may not be enough to sufficiently cool the plate-like member, and there is a risk that the temperature of the semiconductor wafer may not be reduced to a predetermined temperature.

[0005] To improve the heat dissipation performance of the plate-shaped member, it is possible to reduce the thickness of the bonding layer, which has high thermal resistance (low thermal conductivity), as much as possible, or to lower the temperature of the coolant flowing through the coolant flow path. However, if the bonding layer is made too thin, the difference in thermal expansion between the plate-shaped member and the base member can damage the bonding layer, resulting in poor bonding. Another problem is that lowering the coolant temperature increases the cost of installing a cooling system.

[0006] Therefore, the present disclosure has been made to solve the above-mentioned problems, and aims to provide a holding device that can improve the heat dissipation performance of a plate-like member. [Means for solving the problem]

[0007] In order to solve the above problems, one aspect of the present disclosure is to a plate-like member having a first surface and a second surface provided on the opposite side of the first surface; a base member having a third surface and a fourth surface provided on the opposite side of the third surface; a bonding layer disposed between the second surface and the third surface and bonding the plate-like member and the base member, A holding device for holding an object on the first surface of the plate-like member, the base member includes a first refrigerant flow path through which a refrigerant flows; At least one of the plate-like member and the bonding layer is characterized by having a second coolant flow path through which a coolant flows.

[0008] By providing a second refrigerant flow path in at least one of the plate-shaped member and the bonding layer in addition to the first refrigerant flow path in the base member, the plate-shaped member can be cooled with almost no thermal resistance from the bonding layer. This promotes cooling of the plate-shaped member, thereby improving heat dissipation in the plate-shaped member. The second refrigerant flow path can be provided in either the plate-shaped member or the bonding layer, or in both the plate-shaped member and the bonding layer.

[0009] However, if a refrigerant flow path is formed only in at least one of the plate-like member and the bonding layer, the volume (cross-sectional area) of the refrigerant flow path will be small due to the thin thickness of the plate-like member or the bonding layer. Therefore, the refrigerant flow path will be narrower, and the amount of refrigerant that can flow through the refrigerant flow path will be reduced. Therefore, in addition to providing a second refrigerant flow path in at least one of the plate-like member and the bonding layer, a first refrigerant flow path is also provided in the base member.

[0010] In the above-mentioned holding device, When the plate-shaped member includes the second refrigerant flow path, it is preferable that the second refrigerant flow path is disposed inside the plate-shaped member or on at least one of the second surface.

[0011] When the second refrigerant flow path is provided in the plate-shaped member, the second refrigerant flow path can be provided not only inside the plate-shaped member but also on the second surface (the surface in contact with the bonding layer). That is, when the second refrigerant flow path is provided in the plate-shaped member, the second refrigerant flow path can be disposed either inside the plate-shaped member or on the second surface of the plate-shaped member, or on both the inside and second surface of the plate-shaped member. When the second refrigerant flow path is provided on the second surface of the plate-shaped member, a groove is formed in the second surface, and the groove is blocked with the bonding layer to form the second refrigerant flow path.

[0012] In any of the above-mentioned holding devices, It is preferable that the first refrigerant flow path and the second refrigerant flow path are connected to different cooling systems.

[0013] This allows the temperature and flow rate of the refrigerant to be controlled separately for the first and second refrigerant flow paths, thereby enabling efficient cooling of the plate-shaped member and further improving the heat dissipation performance of the plate-shaped member.

[0014] Here, while it is possible to further improve the heat dissipation performance of the plate-shaped member by flowing a refrigerant with the same temperature as the refrigerant flowing through the first refrigerant flow path through the second refrigerant flow path, the temperature difference between the first surface and the interior of the plate-shaped member may become too large, which may damage the plate-shaped member or adversely affect the temperature distribution on the first surface. Therefore, by flowing a refrigerant with a higher temperature through the second refrigerant flow path than the refrigerant flowing through the first refrigerant flow path, it is possible to improve the heat dissipation performance of the plate-shaped member while preventing damage to the plate-shaped member and a decrease in the temperature uniformity on the first surface.

[0015] Furthermore, since the refrigerant flowing through the second refrigerant flow path has a lower flow rate and a higher temperature than the refrigerant flowing through the first refrigerant flow path, the increase in equipment costs associated with installing a new cooling system including the second refrigerant flow path can be reduced.

[0016] In any of the above-mentioned holding devices, the first refrigerant flow path and the second refrigerant flow path are connected to the same cooling system, The second refrigerant flow path preferably branches off from the first refrigerant flow path.

[0017] This allows the first refrigerant flow path and the second refrigerant flow path to be combined into one cooling system, simplifying the configuration of the cooling system and providing an advantage in terms of cost.

[0018] In any of the above-mentioned holding devices, When the second refrigerant flow path is provided inside the plate-like member, the second refrigerant flow path is preferably disposed on the second surface side.

[0019] Placing the second refrigerant flow path on the first surface side can improve heat removal performance on the first surface, but there is a risk that the planar shape of the second refrigerant flow path will be reflected in the temperature distribution on the first surface.

[0020] Therefore, by arranging the second refrigerant flow path on the second surface side, the shape of the second refrigerant flow path in plan view is not reflected in the temperature distribution on the first surface, and the first surface can be cooled evenly, thereby improving heat removal and temperature uniformity on the first surface. [Effects of the Invention]

[0021] According to the present disclosure, it is possible to provide a holding device that can improve the heat dissipation performance of a plate-like member. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a schematic perspective view of an electrostatic chuck according to a first embodiment. [Figure 2] FIG. 2 is a partial cross-sectional view of the electrostatic chuck according to the first embodiment. [Figure 3] 3A and 3B are diagrams showing the schematic shape of a refrigerant flow path provided in a plate-like member. [Figure 4] 10A and 10B are diagrams showing another schematic shape of a coolant flow path provided in a plate-like member. [Figure 5] 4A and 4B are diagrams showing the schematic shape of a refrigerant flow path provided in a base member. [Figure 6] FIG. 10 is a partial cross-sectional view of an electrostatic chuck according to a second embodiment. [Figure 7] FIG. 10 is a partial cross-sectional view of an electrostatic chuck according to a third embodiment. [Figure 8] FIG. 10 is a partial cross-sectional view of an electrostatic chuck according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0023] A holding device according to an embodiment of the present disclosure will be described in detail with reference to the drawings. In this embodiment, an electrostatic chuck used in a semiconductor manufacturing apparatus such as a film forming apparatus (such as a CVD film forming apparatus or a sputtering film forming apparatus) or an etching apparatus (such as a plasma etching apparatus) will be described as an example.

[0024] [First embodiment] First, an electrostatic chuck 1 according to a first embodiment will be described with reference to Figures 1 to 4. The electrostatic chuck 1 according to this embodiment is a device that attracts and holds a semiconductor wafer W (object) by electrostatic attraction, and is used, for example, to fix the semiconductor wafer W in a vacuum chamber of a semiconductor manufacturing device. As shown in Figure 1, the electrostatic chuck 1 includes a plate-shaped member 10, a base member 20, and a bonding layer 30 that bonds the plate-shaped member 10 and the base member 20 together.

[0025] In the following description, for convenience of explanation, the X, Y, and Z axes are defined as shown in Fig. 1. Here, the Z axis is an axis in the axial direction of the electrostatic chuck 1 (the vertical direction in Fig. 1), and the X and Y axes are axes in the radial direction of the electrostatic chuck 1.

[0026] As shown in Fig. 1, the plate-like member 10 is a circular member made of ceramics. Various ceramics can be used, but from the viewpoints of strength, wear resistance, plasma resistance, etc., it is preferable to use ceramics whose main component is, for example, aluminum oxide (alumina, Al2O3) or aluminum nitride (AlN). Note that the term "main component" as used here refers to the component with the highest content (for example, a component with a volume content of 90 vol% or more).

[0027] The diameter of the plate-shaped member 10 is, for example, about 150 to 300 mm. The thickness of the plate-shaped member 10 is, for example, about 2 to 6 mm. The thermal conductivity of the plate-shaped member 10 is preferably within a range of 10 to 50 W / mK (more preferably, 18 to 30 W / mK).

[0028] 1 and 2, the plate-shaped member 10 has a holding surface 11 that holds a semiconductor wafer W, and a bottom surface 12 that is provided on the opposite side of the holding surface 11 in the thickness direction (the direction that coincides with the Z-axis direction) of the plate-shaped member 10. The holding surface 11 is an example of a "first surface" in the present disclosure, and the bottom surface 12 is an example of a "second surface" in the present disclosure.

[0029] 2, the plate-like member 10 is provided therein with a chuck electrode 40 and a heater electrode 50. The chuck electrode 40 has, for example, a substantially circular shape when viewed in the Z-axis direction, and is made of a conductive material (for example, tungsten, molybdenum, etc.). The heater electrode 50 has, for example, a pattern extending in a substantially spiral shape when viewed in the Z-axis direction, and is made of a conductive material (for example, tungsten, molybdenum, platinum, etc.).

[0030] When power is supplied to the chuck electrode 40 from an external power source (not shown), an electrostatic attraction force (adsorption force) is generated, and the semiconductor wafer W is attracted and fixed to the holding surface 11 of the plate-like member 10 by this electrostatic attraction force. Furthermore, when power is supplied to the heater electrode 50 from an external power source (not shown), the heater electrode 50 generates heat, thereby heating the holding surface 11 and, ultimately, the semiconductor wafer W.

[0031] Furthermore, a coolant flow path 13 for flowing a coolant (e.g., a fluorine-based inert liquid, water, etc.) is formed inside the plate-shaped member 10. This coolant flow path 13 is disposed on the underside 12 of the plate-shaped member 10, i.e., below components inside the plate-shaped member 10, such as the heater electrode 50. As shown in FIG. 3, the coolant flow path 13 is formed in a generally spiral shape when viewed in the Z-axis direction, and is connected to a supply port 17 provided on the radially outer side of the plate-shaped member 10 and an outlet port 18 provided in the center of the plate-shaped member 10. The size of this coolant flow path 13 is such that the width (XY direction dimension) X1 is approximately 0.5 mm to 3.0 mm and the height (Z direction dimension) Z1 is approximately 0.3 mm to 1.5 mm (see FIG. 2). The supply port 17 and the outlet port 18 each communicate with a through-hole (not shown) formed in the base member 20.

[0032] As described above, the refrigerant flow path 13 is a narrow flow path (with a small cross-sectional area of ​​the flow path), and therefore the flow rate of the refrigerant that can flow through the refrigerant flow path 13 is small. Therefore, in order to efficiently cool the plate-like member 10, a refrigerant flow path 23 is also provided in the base member 20, as will be described later.

[0033] The coolant supplied from the supply port 17 into the plate-shaped member 10 via the through-holes in the base member 20 flows through the coolant flow path 13 and is discharged from the discharge port 18 to the outside of the plate-shaped member 10 (and further to the outside of the electrostatic chuck 1 via the through-holes in the base member 20). The supply port 17 and the discharge port 18 may be reversed. In this manner, in the electrostatic chuck 1 of this embodiment, the coolant flow path 13 is provided in the plate-shaped member 10, and by flowing the coolant through the coolant flow path 13, the plate-shaped member 10 can be cooled without being subjected to the thermal resistance of the bonding layer 30. The coolant flow path 13 is an example of a "second coolant flow path" in the present disclosure.

[0034] Here, the shape of the coolant flow path 13 as viewed in the Z-axis direction is not limited to the spiral shape shown in Fig. 3, and may be, for example, a shape in which a plurality of fan-shaped flow paths are provided, as shown in Fig. 4. The coolant flow path 13 is formed so as to avoid components such as through-holes (gas holes, lift pin holes, etc.) and vias in the plate-like member 10 (Figs. 3 and 4 show the schematic shape of the coolant flow path 13 with the avoiding parts of the components omitted).

[0035] By forming the refrigerant flow paths 13 in this shape, the flow rate of the refrigerant flowing through the refrigerant flow paths 13 can be increased compared to the spiral shape shown in Fig. 3. In this case, the supply ports 17 in each fan-shaped refrigerant flow path 13 can be provided on the center side of the plate-shaped member 10, and the discharge ports 18 can be provided on the outer periphery side of the plate-shaped member 10. Fig. 4 shows an example in which each refrigerant flow path 13 has one supply port 17 and three discharge ports 18, but the numbers of the supply ports 17 and the discharge ports 18 are not particularly limited, and the supply ports 17 and the discharge ports 18 can be reversed.

[0036] 1, the base member 20 is formed in a cylindrical shape and includes an upper surface 21 and a lower surface 22 provided on the opposite side of the upper surface 21 in the thickness direction (i.e., the Z-axis direction) of the base member 20. The base member 20 is preferably made of a metal (for example, aluminum or an aluminum alloy), but may be made of a material other than metal.

[0037] The diameter of the base member 20 is, for example, about 180 mm to 350 mm. The thickness (dimension in the Z-axis direction) of the base member 20 is, for example, about 20 mm to 50 mm. The thermal conductivity of the base member 20 (assumed to be aluminum) is greater than that of the plate-like member 10, and is desirably within the range of 180 to 250 W / mK (preferably about 230 W / mK).

[0038] As shown in FIG. 5, the base member 20 is formed with a refrigerant flow path 23 for flowing a refrigerant (for example, a fluorine-based inert liquid, water, or the like). The refrigerant flow path 23 is connected to a cooling system different from the cooling system of the refrigerant flow path 13 described above. That is, the refrigerant flowing through the refrigerant flow path 23 and the refrigerant flowing through the refrigerant flow path 13 are controlled separately. As shown in FIG. 5, the refrigerant flow path 23 is formed in a spiral shape when viewed in the Z-axis direction, and is connected to a supply port 27 provided on the outer side of the base member 20 in the radial direction and a discharge port 28 provided in the center of the base member 20. The size of the refrigerant flow path 23 is such that the width (dimension in the XY directions) X2 is approximately 3 mm to 8 mm, and the height (dimension in the Z direction) Z2 is approximately 10 mm to 25 mm (see FIG. 2).

[0039] The coolant supplied to the base member 20 from the supply port 27 flows through the coolant flow path 23 and is discharged to the outside of the base member 20 from the discharge port 28. Note that the supply port 27 and the discharge port 28 may be reversed. In this way, by flowing the coolant through the coolant flow path 23 of the base member 20, the base member 20 is cooled, and thereby the plate-like member 10 is cooled via the bonding layer 30. Note that the coolant flow path 23 is an example of a "first coolant flow path" in the present disclosure.

[0040] As shown in FIG. 1, the bonding layer 30 is disposed between the lower surface 12 of the plate-shaped member 10 and the upper surface 21 of the base member 20, and bonds the plate-shaped member 10 and the base member 20 together. The lower surface 12 of the plate-shaped member 10 and the upper surface 21 of the base member 20 are thermally connected via the bonding layer 30. The bonding layer 30 is made of an adhesive material such as a silicone resin, an acrylic resin, or an epoxy resin, and may contain a filler having thermal conductivity. The thickness of the bonding layer 30 (dimension in the Z-axis direction) is, for example, about 0.1 to 1.0 mm. The thermal conductivity of the bonding layer 30 is, for example, 1.0 W / mK, and the thermal resistance is, for example, 0.0005 m 2 The thermal conductivity of the bonding layer 30 (assumed to be a silicone-based resin) is preferably within a range of 0.1 to 2.0 W / mK (preferably 0.5 to 1.5 W / mK).

[0041] As described above, the thermal conductivity of the bonding layer 30 is much lower than that of the plate-shaped member 10, resulting in a high thermal resistance. Therefore, simply providing a coolant flow path 23 in the base member 20 and flowing a coolant therethrough, as in conventional devices, may not be enough to sufficiently cool the plate-shaped member 10. In particular, in recent years, there have been an increasing number of cases in which the input energy to the semiconductor wafer W increases, for example, due to deeper etching depths, during processing of the semiconductor wafer W. As a result, the heat input to the semiconductor wafer W increases, and there is a risk that the temperature of the semiconductor wafer W may not be reduced to a predetermined temperature.

[0042] Therefore, in the electrostatic chuck 1 of this embodiment, the coolant flow path 13 is also provided in the plate-shaped member 10. By providing the coolant flow path 13 in the plate-shaped member 10 in addition to the coolant flow path 23 provided in the base member 20 in this way, the plate-shaped member 10 can be cooled with almost no thermal resistance from the bonding layer 30. Therefore, the plate-shaped member 10 can be cooled efficiently and the cooling of the plate-shaped member 10 is promoted, so that the heat dissipation performance of the plate-shaped member 10 can be improved.

[0043] In the electrostatic chuck 1 of this embodiment, the coolant flow path 13 and the coolant flow path 23 are connected to separate cooling systems. Therefore, the temperature and flow rate of the coolant can be controlled separately for the coolant flow path 13 and the coolant flow path 23. This allows the plate-shaped member 10 to be cooled efficiently, thereby further improving the heat dissipation performance of the plate-shaped member 10.

[0044] Here, the heat dissipation performance of the plate-shaped member 10 can be further improved by flowing a refrigerant through the refrigerant flow path 13 that has the same temperature as the refrigerant flowing through the refrigerant flow path 13. However, in this case, if the temperature of the refrigerant is too low, the temperature difference between the holding surface 11 and the interior of the plate-shaped member 10 becomes too large, which may damage the plate-shaped member 10 or adversely affect the temperature distribution on the holding surface 11.

[0045] Therefore, in the electrostatic chuck 1 of this embodiment, a refrigerant having a higher temperature than the refrigerant flowing through the refrigerant flow path 23 flows through the refrigerant flow path 13. This makes it possible to improve the heat dissipation performance of the plate-shaped member 10 while preventing damage to the plate-shaped member 10 and a decrease in the temperature uniformity on the holding surface 11.

[0046] Furthermore, the refrigerant flowing through refrigerant flow path 13 has a lower flow rate and a higher temperature than the refrigerant flowing through refrigerant flow path 23, so the increase in equipment costs associated with installing a new cooling system including refrigerant flow path 13 can be suppressed.

[0047] Furthermore, by arranging the refrigerant flow path 13 on the side of the holding surface 11, it is possible to improve the heat removal performance at the holding surface 11. However, if the refrigerant flow path 13 is arranged close to the holding surface 11, the shape of the refrigerant flow path 13 as viewed in the Z-axis direction (plan view) (i.e., the spiral shape in this embodiment) will be reflected in the temperature distribution on the holding surface 11, and there is a risk that the temperature uniformity on the holding surface 11 will decrease.

[0048] For this reason, in the electrostatic chuck 1 of this embodiment, the coolant flow passage 13 is disposed on the lower surface 12 side (below the components in the plate-like member 10, such as the heater electrode 50). In other words, the coolant flow passage 13 is disposed as far away from the holding surface 11 as possible. This prevents the shape of the coolant flow passage 13 in a plan view from being reflected in the temperature distribution on the holding surface 11, and allows the holding surface 11 to be cooled uniformly. Therefore, the heat dissipation property and the temperature uniformity on the holding surface 11 can be improved.

[0049] As described above, according to the electrostatic chuck 1 of the present embodiment, the coolant flow path 13 is provided in the plate-shaped member 10 in addition to the coolant flow path 23 provided in the base member 20, and therefore the plate-shaped member 10 can be efficiently cooled with almost no thermal resistance from the bonding layer 30. Therefore, the cooling of the plate-shaped member 10 is promoted, and the heat dissipation performance of the plate-shaped member 10 can be improved.

[0050] [Second embodiment] Next, a second embodiment will be described. The second embodiment has the same basic configuration as the first embodiment, but differs from the first embodiment in that the refrigerant flow path 13 is provided on the lower surface 12 rather than inside the plate-shaped member 10. Therefore, the same components as those in the first embodiment will be given the same reference numerals and their description will be omitted as appropriate, and the description will focus on the differences from the first embodiment.

[0051] As shown in FIG. 6 , in the electrostatic chuck 1a of the second embodiment, a coolant flow path 13 is provided on the lower surface 12. Specifically, grooves serving as the coolant flow paths 13 are machined on the lower surface 12 of the plate-shaped member 10, and the grooves are blocked with the bonding layer 30 to form the coolant flow paths 13. Providing the coolant flow paths 13 on the lower surface 12 of the plate-shaped member 10 in this manner simplifies the processing compared to providing the coolant flow paths 13 inside the plate-shaped member 10. Furthermore, even when the coolant flow paths 13 are provided on the lower surface 12 of the plate-shaped member 10, the plate-shaped member 10 can be cooled by the coolant flowing through the coolant flow paths 13 without experiencing thermal resistance from the bonding layer 30, as in the first embodiment. Furthermore, by providing the coolant flow paths 13 on the lower surface 12 of the plate-shaped member 10, the coolant flow paths 13 are positioned at the farthest position from the holding surface 11. Therefore, the plate-shaped member 10 can be cooled more uniformly, thereby further improving the thermal uniformity on the holding surface 11.

[0052] Therefore, according to the electrostatic chuck 1a of this embodiment, in addition to the coolant flow path 23 provided in the base member 20, the coolant flow path 13 is provided in the plate-shaped member 10, which greatly simplifies processing (forming the coolant flow path 13). As in the first embodiment, the coolant flowing through the coolant flow path 13 provided in the lower surface 12 of the plate-shaped member 10 can efficiently cool the plate-shaped member 10 without being subjected to the thermal resistance of the bonding layer 30. Furthermore, by providing the coolant flow path 13 on the lower surface 12 of the plate-shaped member 10, the plate-shaped member 10 can be cooled more uniformly. As a result, the plate-shaped member 10 is cooled effectively and uniformly, which improves the heat dissipation performance of the plate-shaped member 10 and improves the temperature uniformity on the holding surface 11.

[0053] [Third embodiment] Next, a third embodiment will be described. The third embodiment has the same basic configuration as the first embodiment, but differs from the first embodiment in that the refrigerant flow path 13 and the refrigerant flow path 23 are connected to the same cooling system. Therefore, the same components as those in the first embodiment will be assigned the same reference numerals and their description will be omitted as appropriate, and the description will focus on the differences from the first embodiment.

[0054] As shown in FIG. 7 , in the electrostatic chuck 1b of the third embodiment, the coolant flow path 13 is branched from the coolant flow path 23 and configured as a flow path. Specifically, a supply port 17 of the coolant flow path 13 is connected to the coolant flow path 23 (outer periphery side), and an outlet 18 of the coolant flow path 13 is connected to the coolant flow path 23 (center side). That is, the coolant flow path 23 and the coolant flow path 13 are connected to the same cooling system. As a result, a portion of the coolant flowing in the coolant flow path 23 (outer periphery side) flows from the supply port 17 into the coolant flow path 13, and the coolant that has flowed in the coolant flow path 13 is discharged from the outlet 18 and joins the coolant flowing in the coolant flow path 23 (center side). Therefore, similar to the first embodiment, the coolant flowing in the coolant flow path 13 can cool the plate-shaped member 10 without being subjected to the thermal resistance of the bonding layer 30. Furthermore, since the coolant flow path 13 and the coolant flow path 23 form a single cooling system, the configuration of the cooling system can be simplified.

[0055] Therefore, according to the electrostatic chuck 1b of the present embodiment, the coolant flow path 13 is provided in the plate-shaped member 10 so as to branch off from the coolant flow path 23 provided in the base member 20, so there is no need to provide separate cooling systems for the coolant flow path 13 and the coolant flow path 23. Then, similar to the first embodiment, the coolant flowing through the coolant flow path 13 provided in the plate-shaped member 10 can efficiently cool the plate-shaped member 10 without being subjected to the thermal resistance of the bonding layer 30. As a result, it is possible to suppress an increase in equipment costs for the cooling system and improve the heat dissipation performance of the plate-shaped member 10.

[0056] [Fourth embodiment] Finally, a fourth embodiment will be described. The fourth embodiment has the same basic configuration as the first embodiment, but differs from the first embodiment in that a coolant flow path 33 is provided in the bonding layer 30 instead of providing the coolant flow path 13 in the plate-like member 10. Therefore, the same components as in the first embodiment will be given the same reference numerals and their description will be omitted as appropriate, and the description will focus on the differences from the first embodiment.

[0057] 8, in the electrostatic chuck 1c of the fourth embodiment, the coolant flow passage 33 is provided in the bonding layer 30. Providing the coolant flow passage 33 in the bonding layer 30 in this manner is easier than providing the coolant flow passage 13 in the plate-shaped member 10, and therefore, an increase in product costs can be suppressed. Furthermore, by providing the coolant flow passage 33, the plate-shaped member 10 can be cooled efficiently.

[0058] However, since the thickness of the bonding layer 30 cannot be increased, the dimension of the coolant flow path 33 in the Z-axis direction is smaller than that of the coolant flow path 13. Therefore, although the electrostatic chuck 1c of this embodiment has inferior heat dissipation performance to the above-described embodiments, it can have improved heat dissipation performance compared to conventional electrostatic chucks.

[0059] Therefore, according to the electrostatic chuck 1c of this embodiment, it is possible to improve the heat dissipation performance of the plate-shaped member 10 while suppressing the increase in product costs that would be associated with providing a new refrigerant flow path 33 in addition to the refrigerant flow path 23 provided in the base member 20 (this can be achieved more cheaply than providing the refrigerant flow path 13).

[0060] It should be noted that the above-described embodiment is merely an example and does not limit the present disclosure in any way, and various improvements and modifications are possible without departing from the spirit and scope of the present disclosure. For example, in the above-described embodiment, an example was given in which either the refrigerant flow path 13 or the refrigerant flow path 33 is provided in addition to the refrigerant flow path 23, but it is also possible to provide both the refrigerant flow path 13 and the refrigerant flow path 33. This can further improve the heat dissipation performance of the plate-shaped member 10.

[0061] Furthermore, although the first to third embodiments have been described as examples in which the refrigerant flow paths 13 are provided in the plate-shaped member 10, the refrigerant flow paths 13 may be provided both inside the plate-shaped member 10 and on the lower surface 12. This can further improve the heat dissipation properties of the plate-shaped member 10. [Explanation of symbols]

[0062] 1. Electrostatic chuck 1a Electrostatic chuck 1b Electrostatic chuck 1c Electrostatic chuck 10 Plate-shaped member 11 Holding surface 12 Bottom side 13 Refrigerant flow path 20 Base member 21 Top side 22 Bottom side 23 Refrigerant flow path 30 Bonding layer 33 Refrigerant flow path W: Semiconductor wafer (object)

Claims

1. a plate-like member having a first surface and a second surface provided on the opposite side of the first surface; a base member including a third surface and a fourth surface provided on the opposite side of the third surface; a bonding layer disposed between the second surface and the third surface and bonding the plate-like member and the base member, A holding device for holding an object on the first surface of the plate-like member, the base member includes a first refrigerant flow path through which a liquid refrigerant flows; At least one of the plate-like member and the bonding layer includes a second refrigerant flow path through which a liquid refrigerant flows, When the plate-like member is positioned on the upper side in the vertical direction and the base member is positioned on the lower side in the vertical direction, the second refrigerant flow path is disposed below components within the plate-like member. A holding device characterized by:

2. 2. The holding device according to claim 1, When the plate-shaped member includes the second refrigerant flow path, the second refrigerant flow path is disposed on at least one of the inside of the plate-shaped member and the second surface. A holding device characterized by:

3. The holding device according to claim 1 or 2, The first refrigerant flow path and the second refrigerant flow path are connected to different cooling systems. A holding device characterized by:

4. The holding device according to claim 1 or 2, the first refrigerant flow path and the second refrigerant flow path are connected to the same cooling system, The second refrigerant flow path branches off from the first refrigerant flow path. A holding device characterized by:

5. 2. The holding device according to claim 1, When the second refrigerant flow path is provided inside the plate-like member, the second refrigerant flow path is arranged on the second surface side. A holding device characterized by:

6. A plate-like member having a first surface and a second surface provided on the opposite side of the first surface; a base member including a third surface and a fourth surface provided on the opposite side of the third surface; a bonding layer disposed between the second surface and the third surface and bonding the plate-like member and the base member, A holding device for holding an object on the first surface of the plate-like member, the base member includes a first refrigerant flow path through which a refrigerant flows; At least one of the plate-like member and the bonding layer includes a second refrigerant flow path through which a refrigerant flows, When the plate-like member is positioned on the upper side in the vertical direction and the base member is positioned on the lower side in the vertical direction, the second refrigerant flow path is disposed below components within the plate-like member, the first refrigerant flow path and the second refrigerant flow path are connected to the same cooling system, The second refrigerant flow path branches off from the first refrigerant flow path. A holding device characterized by:

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