Holding device

Abstract

To provide a holding device capable of improving an insulation property around a terminal and of electrically connecting between an external power supply and the terminal via a resin connector.SOLUTION: An electrostatic chuck 1 that holds a semiconductor wafer W on a holding surface 11 of a plate-like member 10, has: the plate-like member 10 that comprises terminal pads 60 connected with internal electrodes 50 and 52; a base member 20 that comprises through-holes 25 and cooling medium passages 23; terminal members 70 each comprising a conductive member 71 whose one end is connected with the terminal pad 60 and whose the other end is connected with a connector 80, being arranged inside each through-hole 25; and a bonding layer 40 bonding between the plate-like member 10 and the base member 20. The bonding layer 40 is formed of an inorganic bonding material whose main component is an inorganic material. Each terminal member 70 is arranged between the cooling medium passages 23 of the base member 20, and the conductive member 71 is formed in a ceramic member 72.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] A known holding device is, for example, an electrostatic chuck described in Patent Document 1. This electrostatic chuck includes a ceramic substrate (first member) that holds a semiconductor wafer on its surface (holding surface) and a metal base member (second member) bonded to the ceramic substrate. Internal electrodes, such as a chuck electrode and a heater electrode, are disposed within the ceramic substrate. This electrostatic chuck includes a first terminal disposed on the underside of the ceramic substrate and electrically connected to the internal electrode, for supplying power to the internal electrode. A second terminal, one end of which is connected to an external power source and the other end of which is connected to the first terminal, is disposed within a through-hole formed in the base member. An insulating tube is disposed around the terminals to insulate the first and second terminals from the base member. The insulating tube is fixed to the electrostatic chuck with a resin adhesive. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-103321 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in recent years, electrostatic chucks have increasingly been used at high temperatures (250°C or higher), which means that resin adhesives are no longer able to secure the insulating tubes, potentially resulting in insufficient insulation around the terminals. Furthermore, when electrostatic chucks are used at high temperatures (250°C or higher), it may become impossible to use the resin connectors that are connected to the terminals and disposed on the underside of the base member to connect the terminals to an external power supply.

[0005] Therefore, the present disclosure has been made to solve the above-mentioned problems, and aims to provide a holding device that improves the insulation around the terminal and can electrically connect an external power source and the terminal via a resin connector. [Means for solving the problem]

[0006] In order to solve the above problems, one aspect of the present disclosure is to a first member including a first surface, a second surface provided on the opposite side to the first surface, and a terminal pad provided on the second surface and connected to an internal electrode; a second member including a third surface, a fourth surface provided on the opposite side of the third surface, a through hole penetrating the third surface and the fourth surface, and a refrigerant flow path through which a refrigerant flows; a terminal member disposed inside the through hole, the terminal member having a conductive member having one end connected to the terminal pad and the other end connected to a connector; a bonding layer disposed between the second surface of the first member and the third surface of the second member to bond the first member and the second member, A holding device that holds an object on the first surface of the first member, the bonding layer is formed of an inorganic bonding material containing an inorganic material as a main component, The terminal member is disposed between the refrigerant flow paths of the second member, and the conductive member is formed within a ceramic member.

[0007] In this holding device, the bonding layer is formed from an inorganic bonding material whose main component is an inorganic material (for example, metal such as solder, or ceramic such as alumina or zirconia), which improves heat resistance and prevents poor bonding between the first and second members even when used at high temperatures. Furthermore, the conductive member provided on the terminal member and connected to the terminal pad is formed within the ceramic member, so the ceramic member ensures insulation around the terminal (between the terminal pad or conductive member and the bonding layer or second member).

[0008] Furthermore, because the terminal member is disposed between the refrigerant flow paths, the terminal member is easily cooled by the refrigerant and the conductive member is less likely to become hot. Therefore, even when the holding device is used at high temperatures (250°C or higher), a resin connector can be connected to the other end of the conductive member, allowing for a stable electrical connection between the external power source and the terminal via the connector.

[0009] In this way, this holding device improves the insulation around the terminals at high temperatures (250°C or higher), and allows the terminals to be electrically connected to an external power source via a resin connector.

[0010] In the above-mentioned holding device, The terminal member is preferably joined to the second member on the fourth surface side of an upper surface that forms the refrigerant flow path.

[0011] In this way, by joining the terminal member to the second member on the fourth surface side of the second member, where the temperature is lower, it is possible to promote heat transfer from the terminal member to the coldest part of the second member. This effectively reduces the temperature of the terminal member (conductive member). Therefore, it is possible to further reduce the temperature of the connector connected to the conductive member, and it is possible to stably electrically connect the external power source and the terminal via the resin connector even when used at high temperatures.

[0012] In the above-mentioned holding device, It is preferable that a gap is formed between the terminal member and the through hole.

[0013] Here, if there is a difference in thermal expansion between the material forming the first member and the material forming the second member, when the temperature of the holding device rises / falls, the difference in thermal expansion may cause the terminal member to come into contact with the second member, which may result in damage to the terminal member.

[0014] Therefore, by forming a gap between the terminal member and the through hole in this manner, damage to the terminal member can be reliably prevented, and the terminal member can improve the insulation between the terminal pad or the conductive member and the bonding layer or the second member.

[0015] In the above-mentioned holding device, the conductive member is brazed to the terminal pad, a cylindrical member disposed in the through hole so as to cover an outer periphery of the terminal member; The cylindrical member is integrally formed with the first member. It is preferable.

[0016] When the terminal member is joined to the first member with the conductive member and the terminal pad brazed, a gap may be formed between the terminal member and the first member. If a gap is formed between the terminal member and the first member when the bonding layer or the second member is made of a conductive material such as a metal material, the insulation between the terminal pad or the conductive member and the bonding layer or the second member may become insufficient.

[0017] Therefore, by placing a tubular member formed integrally with the first member within the through hole so as to cover the outer periphery of the terminal member, the tubular member can reliably improve the insulation between the terminal pad or conductive member and the bonding layer or second member.

[0018] In the above-mentioned holding device, It is preferable that a gap is formed between the cylindrical member and the through hole.

[0019] Here, if there is a difference in thermal expansion between the material forming the tubular member and the material forming the second member, when the temperature of the holding device rises / falls, the difference in thermal expansion may cause the tubular member to come into contact with the second member, which may result in damage to the tubular member.

[0020] Therefore, by forming a gap between the tubular member and the through hole in this manner, damage to the tubular member can be reliably prevented, and the tubular member can improve the insulation between the terminal pad or the conductive member and the bonding layer or the second member. [Effects of the Invention]

[0021] According to the present disclosure, it is possible to provide a holding device that improves the insulation around the terminal and can electrically connect the terminal to an external power source via a resin connector. [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] 1 is a schematic configuration diagram of an XZ cross section of an electrostatic chuck according to a first embodiment. [Figure 3] 1 is a schematic configuration diagram of an electrostatic chuck in an XY plane according to a first embodiment. [Figure 4] FIG. 3 is an enlarged view of the X1 portion shown in FIG. [Figure 5] FIG. 2 is a schematic diagram of the XY cross section of the base member. [Figure 6] FIG. 10 is a schematic configuration diagram of an XZ cross section of an electrostatic chuck according to a second embodiment. [Figure 7] FIG. 7 is an enlarged view of the X2 portion shown in FIG. [Figure 8] FIG. 10 is a schematic configuration diagram of an XZ cross section of an electrostatic chuck showing a modified example. 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, the holding device will be described by taking as an example an electrostatic chuck used in semiconductor manufacturing equipment 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).

[0024] [First embodiment] First, an electrostatic chuck 1 according to a first embodiment will be described with reference to FIGS. 1 to 5. 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 FIG. 1, the electrostatic chuck 1 includes a plate-shaped member 10, a base member 20, and a bonding layer 40 that bonds the plate-shaped member 10 and the base member 20 together. The plate-shaped member 10 is an example of a "first member" in the present disclosure, and the base member 20 is an example of a "second member" in the present disclosure.

[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-shaped member 10 is a disk-shaped 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" here refers to the component with the highest content (for example, a component with a volume content of 90 vol% or more). The diameter of the plate-shaped member 10 is, for example, about 150 mm to 350 mm, and the thickness of the plate-shaped member 10 is, for example, about 2 mm to 6 mm.

[0027] 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 of the plate-shaped member 10 (a direction that coincides with the Z-axis direction, the up-down direction). The semiconductor wafer W is held on this holding surface 11. Note that 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.

[0028] The holding surface 11 of the plate-like member 10 has an uneven shape. Specifically, as shown in Figs. 2 and 3, a ring-shaped convex seal band 16 is formed near the outer edge of the holding surface 11, and a plurality of independent columnar convex portions 17 are formed inside the seal band 16. The cross section (XZ cross section) of the seal band 16 is substantially rectangular, as shown in Fig. 2. The height (dimension in the Z-axis direction) of the seal band 16 is, for example, about 10 µm to 20 µm. The width (dimension in the X-axis direction) of the seal band 16 is, for example, about 0.5 mm to 5.0 mm.

[0029] As shown in Fig. 3, each of the protrusions 17 has a substantially circular shape when viewed in the Z-axis direction (plan view), and is arranged at substantially equal intervals. Furthermore, the cross-sectional shape (XZ cross-section) of each of the protrusions 17 is substantially rectangular, as shown in Fig. 2. The height of each of the protrusions 17 is substantially the same as the height of the seal band 16, and is, for example, about 10 to 20 µm. Furthermore, the width of each of the protrusions 17 (maximum diameter of each of the protrusions 17 when viewed in the Z-axis direction) is, for example, about 0.5 to 1.5 mm. The portions of the holding surface 11 of the plate-like member 10 inside the seal band 16 where no protrusions 17 are formed are recesses 18.

[0030] The semiconductor wafer W is supported by the seal band 16 and the plurality of protrusions 17 on the holding surface 11 of the plate-like member 10 and is held by the electrostatic chuck 1. When the semiconductor wafer W is held by the electrostatic chuck 1, a space S exists between the surface (lower surface) of the semiconductor wafer W and the holding surface 11 of the plate-like member 10 (more specifically, the recesses 18 on the holding surface 11) (see FIG. 2). An inert gas (e.g., helium gas) is supplied to this space S through gas holes 30b (see FIG. 3) that penetrate the electrostatic chuck 1. As shown in FIG. 3, the electrostatic chuck 1 has, as through-holes that penetrate the electrostatic chuck 1, lift pin insertion holes 30a through which lift pins that push up the semiconductor wafer W from above the holding surface 11 are disposed, in addition to the gas holes 30b. In the following description, the lift pin insertion holes 30a and the gas holes 30b may also be simply referred to as "through-holes 30."

[0031] 2, the plate-shaped member 10 has therein a chuck electrode 50 and a heater electrode 52. The chuck electrode 50 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 52 has, for example, a substantially spiral pattern when viewed in the Z-axis direction, and is made of a conductive material (for example, tungsten, molybdenum, platinum, etc.). The chuck electrode 50 and the heater electrode 52 are examples of the "internal electrode" of the present disclosure.

[0032] Here, the power supply structure to the chuck electrode 50 will be described with reference to FIG. 4 as well. First, a via 61 is connected to the chuck electrode 50 as shown in FIG. 2. This via 61 is arranged to extend in the Z-axis direction from the chuck electrode 50 toward the lower surface 12. The other end of the via 61 is connected to a terminal pad 60. As a result, the terminal pad 60 is electrically connected to the chuck electrode 50 through the via 61. The terminal pad 60 and the via 61 are formed of a conductive material (e.g., tungsten, molybdenum, etc.).

[0033] 2 and 4, the terminal pad 60 is disposed at the bottom 15b of a bottomed hole 15 provided in the lower surface 12 of the plate-like member 10. The shape of the terminal pad 60 as viewed in the Z-axis direction is, for example, substantially circular. The bottomed hole 15 is a circular recess, and as viewed in the Z-axis direction, an area that overlaps with a through-hole 25 of the base member 20 (described later) is recessed toward the holding surface 11.

[0034] As shown in FIG. 4, a conductive member 71 provided on a terminal member 70 is connected to this terminal pad 60. The terminal member 70 is a member in which the conductive member 71 is disposed inside a cylindrical ceramic member 72 (the conductive member 71 is covered by the ceramic member 72), and the ceramic member 72 and the plate-shaped member 10 are fired simultaneously to be formed integrally with the plate-shaped member 10. As a result, the terminal pads 60 and the terminal pads 71a are completely covered by the terminal member 70 (ceramic member 72) and the plate-shaped member 10. The tip of the ceramic member 72 is located on approximately the same plane as the lower surface 22 of the base member 20. Like the plate-shaped member 10, the ceramic member 72 is formed of ceramic, and is formed of the same material as the plate-shaped member 10.

[0035] The terminal member 70 can be fabricated (co-fired) by first fabricating a cylindrical ceramic terminal (terminal member 70 before sintering) from a green sheet containing a conductive paste that will become the conductive member 71, inserting the ceramic terminal into the countersunk hole (bottomed hole 15) on the underside of the plate-shaped member before sintering, bonding the ceramic terminal and the plate-shaped member before sintering using a solvent and thermocompression bonding, and then sintering (co-firing) them together. Alternatively, a plate-shaped member in the form of a thick green sheet containing a conductive paste that will become the conductive member 71 in the position where the terminal member 70 will be located may be formed, sintering the plate-shaped member, and then removing unnecessary portions of the sintered plate-shaped member other than the plate-shaped member 10 and the terminal member 70 by machining such as polishing. Alternatively, the plate-shaped member before sintering and the cylindrical ceramic terminal containing a conductive paste that will become the conductive member 71 may be formed together from a green sheet and then sintered.

[0036] The end of the conductive member 71 provided on the terminal member 70 is provided with a terminal pad 71a that connects to the terminal pad 60 and a terminal pad 71b that is exposed to the outside at the end of the ceramic member 72. A male terminal 71c is joined to the terminal pad 71b by brazing. The conductive member 71, the terminal pads 71a and 71b, and the male terminal 71c are an example of the "conductive member" of the present disclosure.

[0037] A connector 80 connected to an external power supply is fitted into the male terminal 71c. The connector 80 includes a female terminal 82 inside a resin member 81, and the female terminal 82 is connected to the external power supply via a wiring 83. Therefore, by connecting the connector 80 to the terminal member 70, that is, by fitting the female terminal 82 of the connector 80 into the male terminal 71c, the external power supply and the terminal pad 60 are electrically connected via the terminal member 70. As a result, power is supplied from the external power supply to the chuck electrode 50 via the terminal member 70 (conductive member 71), the terminal pad 60, and the via 61.

[0038] 2, the power supply structure to the heater electrode 52 is different in that the terminal pad 60 is not directly connected to the heater electrode 52 by the via 61 but is electrically connected to the heater electrode 52 via the connection pad 63. Specifically, the terminal pad 60 is electrically connected to the heater electrode 52 by the via 61, and the connection pad 63 is electrically connected to the heater electrode 52 by the via 62. As a result, power is supplied to the heater electrode 52 from the external power source via the connector 80, the terminal member 70 (conductive member 71), the terminal pad 60, the via 61, the connection pad 63, and the via 62.

[0039] 1, the base member 20 is cylindrical, more specifically, a stepped cylindrical shape formed by stacking two cylinders of different diameters, with the lower surface of the smaller diameter cylinder placed on the upper surface of the larger diameter cylinder, and with a common central axis Ca. The base member 20 is made of metal (e.g., aluminum, aluminum alloy, etc.).

[0040] 1 and 2, the base member 20 has an upper surface 21 and a lower surface 22 provided on the opposite side of the upper surface 21 in the direction of the central axis Ca (see FIG. 2) of the base member 20 (plate-shaped member 10) (i.e., the Z-axis direction). The upper surface 21 is an example of a "third surface" in the present disclosure, and the lower surface 22 is an example of a "fourth surface" in the present disclosure.

[0041] The diameter of the upper portion of the base member 20 is, for example, about 150 mm to 300 mm, and the diameter of the lower portion is, for example, about 180 mm to 350 mm. The thickness of the base member 20 (dimension in the Z-axis direction) is, for example, about 20 mm to 50 mm.

[0042] 2, the base member 20 is formed with a coolant flow path 23 for flowing a coolant (e.g., a fluorine-based inert liquid, water, etc.). As shown in FIG. 5, the coolant 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 radially outer side of the base member 20 and an outlet 28 provided in the center of the base member 20. 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 outlet 28, as shown by the arrows in FIG. 5. The supply port 27 and the outlet 28 may be reversed. In this way, by flowing a 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 40.

[0043] As shown in FIG. 2, the base member 20 has a cylindrical through-hole 25 penetrating between the upper surface 21 and the lower surface 22 in the thickness direction (the Z-axis direction, the up-down direction in FIG. 2). The through-hole 25 is provided between the refrigerant flow paths 23 in an XZ cross-sectional view (a position sandwiched between adjacent refrigerant flow paths 23 in a Z-axis view). A terminal member 70 is disposed in the through-hole 25 and bonded to the base member 20 with an adhesive 26 on the lower surface 22 side of the base member 20 relative to the upper surface 23a forming the refrigerant flow path 23 (i.e., between the upper surface 23a and the lower surface 22 in the Z-axis direction). In this embodiment, the terminal member 70 is bonded to the base member 20 near the lower surface 22 of the base member 20. In this embodiment, a tip portion of the terminal member 70 is bonded to the base member 20 with, for example, the adhesive 26. A gap 35 (see FIG. 4) is formed between the terminal member 70 and the through-hole 25.

[0044] 2, the bonding layer 40 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 to the base member 20. 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 40. The thickness of the bonding layer 40 (the dimension in the Z-axis direction) is, for example, about 0.1 to 1.0 mm.

[0045] The bonding layer 40 is made of an inorganic bonding material whose main component is an inorganic material (for example, a metal such as solder, or a ceramic such as alumina or zirconia). Generally, a resin adhesive is often used as the bonding layer 40. However, when the electrostatic chuck 1 is used at high temperatures (for example, 250°C or higher), the resin adhesive may have insufficient heat resistance and may cause bonding defects, so an inorganic bonding material is used instead. The use of such an inorganic bonding material improves heat resistance, so that bonding defects between the plate-like member 10 and the base member 20 can be prevented even when the electrostatic chuck 1 is used at high temperatures.

[0046] When a metal bonding material containing a metal material as a main component is used as the inorganic bonding material, for example, a metal adhesive that uses metal powder or metal foil for bonding, a material composed of a metal mesh such as metal fiber, a porous material, or a mesh structure and a brazing material, or a material composed of multiple columnar metal pieces and a brazing material, etc. Metals that can be used to form the metal adhesive, metal mesh, or metal pieces include titanium, nickel, aluminum, copper, brass, alloys of these, and stainless steel.

[0047] 2, a bonding layer through hole 45 in which a terminal member 70 is disposed is formed in the bonding layer 40. That is, the cylindrical bonding layer through hole 45 is formed between the bottomed hole 15 and the through hole 25. The bonding layer through hole 45 is coaxial with the bottomed hole 15 and the through hole 25, and the bottomed hole 15, the bonding layer through hole 45, and the through hole 25 are arranged in series in the Z-axis direction (the axial direction of the electrostatic chuck 1), thereby forming a terminal hole 65 (see FIG. 4) in which a terminal pad 60 and a terminal member 70 are disposed.

[0048] When the electrostatic chuck 1 is used at high temperatures (e.g., 250°C or higher), it is difficult to place an insulating tube around the terminal and bond the insulating tube to the electrostatic chuck with a resin adhesive, as is done in conventional electrostatic chucks, resulting in a decrease in insulation. Because the resin adhesive deteriorates at high temperatures, gaps form in the bonded portion or the adhesive itself is damaged, and these gaps or damaged portions become leak paths. When a leak path is created, the insulation between the terminal pad 60 and the base member 20 or the bonding layer 40 (if made of a metal bonding material) breaks down, resulting in abnormal discharge.

[0049] Therefore, in the electrostatic chuck 1 of this embodiment, the terminal member 70, which includes the conductive member 71 (terminal pad 71a) connected to the terminal pad 60 within the ceramic member 72, is integrally formed with the plate-shaped member 10 by co-firing. As a result, the terminal pads 60 and 71a are completely covered by the ceramic member 72 of the terminal member 70 and the plate-shaped member 10. Therefore, even when the electrostatic chuck 1 is used at high temperatures, insulation can be ensured between the terminal pads 60 and 71a and the base member 20 or the bonding layer 40 (when made of a metal bonding material).

[0050] Furthermore, in the electrostatic chuck 1 of this embodiment, the terminal member 70 is disposed between the refrigerant flow paths 23. This allows the terminal member 70 to be easily cooled by the refrigerant, and the conductive member 71 in the terminal member 70 is less likely to become hot. The terminal member 70 is bonded to the base member 20 with the adhesive 26 on the lower surface 22 side of the base member 20 (in this embodiment, near the lower surface 22, which has a lower temperature) rather than the upper surface 23a that forms the refrigerant flow path 23. This promotes heat transfer from the terminal member 70 to the lower temperature portion of the base member 20 via the adhesive 26, thereby more effectively cooling the terminal member 70 (conductive member 71). Therefore, even at high temperatures, a resin connector 80 can be connected to the male terminal 71c provided at the other end of the conductive member 71. This ensures stable electrical connection between the external power supply and the electrostatic chuck 1 via the connector 80, even at high temperatures.

[0051] In the electrostatic chuck 1 of this embodiment, there is a difference in thermal expansion between the material (ceramics) forming the plate-shaped member 10 and the material (metal) forming the base member 20, and therefore, when the temperature of the electrostatic chuck 1 rises or falls, the difference in thermal expansion may cause the terminal member 70 to come into contact with the base member 20, which may result in damage to the terminal member 70. In particular, when the electrostatic chuck 1 is used at high temperatures, the amount of deformation due to the difference in thermal expansion increases, increasing the risk of damage to the terminal member 70.

[0052] Therefore, in the electrostatic chuck 1 of this embodiment, a gap 35 is formed between the terminal member 70 and the through hole 25. The gap 35 may be set to a size (for example, about 0.1 to 2.0 mm) that prevents the terminal member 70 from contacting the base member 20 even due to a difference in thermal expansion between the terminal member 70 and the base member 20. By forming such a gap 35, damage to the terminal member 70 can be reliably prevented. As a result, the terminal member 70 can ensure insulation between the terminal pad 60 or the conductive member 71 and the base member 20 or the bonding layer 40 (when made of a metal bonding material).

[0053] As described above, according to the electrostatic chuck 1 of this embodiment, the terminal member 70, in which the conductive member 71 is formed in the ceramic member 72, is integrally formed with the plate-shaped member 10 by co-firing. Therefore, insulation around the terminal (between the terminal pad 60 or the conductive member 71 and the base member 20 or the bonding layer 40 (when made of a metal bonding material)) can be ensured even at high temperatures. The terminal member 70 is disposed between the refrigerant flow paths 23 of the base member 20 and bonded to the lower surface 22 of the base member 20 with the adhesive 26. Therefore, even at high temperatures, the terminal member 70 (conductive member 71) can be efficiently cooled by the refrigerant flowing through the refrigerant flow paths 23, and the conductive member 71 is unlikely to become too hot. Therefore, even when the electrostatic chuck 1 is used at high temperatures, a resin connector 80 can be connected to the male terminal 71c provided at the other end of the conductive member 71. This allows a stable electrical connection between an external power source and the electrostatic chuck 1 via the connector 80.

[0054] [Second embodiment] Next, a second embodiment will be described with reference to Figures 6 and 7. The second embodiment has the same basic configuration as the first embodiment, but differs from the first embodiment in that the terminal member is not integrally formed with the plate-shaped member and an insulating sleeve (cylindrical member) is provided to surround the terminal member. 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.

[0055] In the electrostatic chuck 1a of this embodiment, as shown in FIGS. 6 and 7 , the terminal member 70 is not integrally formed with the plate-shaped member 10, but the terminal pad 60 and the terminal pad 71a are joined by brazing. That is, the end face of the terminal member 70 and the plate-shaped member 10 (the bottom 15b of the bottomed hole 15) are in contact but not joined. Therefore, a gap may be formed between the terminal member 70 and the plate-shaped member 10. If a gap is formed between the terminal member 70 and the plate-shaped member 10, insulation between the terminal pad 60 or the conductive member 71 and the base member 20 or the bonding layer 40 (if made of a metal bonding material) may be insufficient. In particular, there is a high risk of insufficient insulation in the power supply path to the chuck electrode 50, to which the highest voltage is applied among the internal electrodes. The terminal member 70 of this embodiment may be manufactured using a green sheet, as in the first embodiment, or may be manufactured by placing a metal member serving as the conductive member 71 in ceramic powder and applying heat and pressure.

[0056] Therefore, a cylindrical ceramic insulating sleeve 75 is disposed in the through hole 25 so as to surround the outer periphery of the terminal member 70. The end of this insulating sleeve 75 is diffusion-bonded to the plate-shaped member 10 (bottomed hole 15) to form it integrally with the plate-shaped member 10. By providing such an insulating sleeve 75, insulation can be ensured between the terminal pad 60 or the conductive member 71 and the base member 20 or the bonding layer 40 (when made of a metal bonding material) even at high temperatures.

[0057] The insulating sleeve 75 is bonded to the base member 20 by an adhesive 76 near the lower surface 22 of the base member 20. The terminal member 70 is bonded to the insulating sleeve 75 by an adhesive 26 near the lower surface 22 of the base member 20. This promotes heat transfer from the terminal member 70 to a low-temperature portion of the base member 20 via the adhesive 26, the insulating sleeve 75, and the adhesive 76, thereby effectively cooling the terminal member 70 (conductive member 71). Therefore, even at high temperatures, a resin connector 80 can be connected to the male terminal 71c provided at the other end of the conductive member 71. This ensures stable electrical connection between an external power supply and the electrostatic chuck 1a via the connector 80, even at high temperatures.

[0058] Here, since there is a difference in thermal expansion between the material (ceramics) forming the insulating sleeve 75 and the material (metal) forming the base member 20, when the temperature of the electrostatic chuck 1a rises / falls, the difference in thermal expansion may cause the insulating sleeve 75 to come into contact with the base member 20, which may result in damage to the insulating sleeve 75.

[0059] Therefore, in the electrostatic chuck 1a of this embodiment, a gap 77 is formed between the insulating sleeve 75 and the base member 20 (see FIG. 7). The gap 77 may be set to a size (e.g., about 0.1 to 2.0 mm) that prevents the insulating sleeve 75 from contacting the base member 20 even due to a difference in thermal expansion between the insulating sleeve 75 and the base member 20. By forming such a gap 77, damage to the insulating sleeve 75 can be reliably prevented. As a result, the insulating sleeve 75 can ensure insulation between the terminal pads 60 or the conductive members 71 and the base member 20 or the bonding layer 40 (when made of a metal bonding material).

[0060] As described above, according to the electrostatic chuck 1a of the present embodiment, the terminal member 70 is not integrally formed with the plate-shaped member 10, and the terminal pad 60 and the terminal member 70 (conductive member 71) are connected by brazing the terminal pad 60 to the terminal pad 71a, but the insulating sleeve 75 arranged to surround the terminal member 70 is diffusion-bonded to the plate-shaped member 10, and the insulating sleeve 75 and the plate-shaped member 10 are integrally formed. Therefore, even at high temperatures, the insulating sleeve 75 can ensure insulation between the terminal pad 60 or the conductive member 71 and the base member 20 or the bonding layer 40 (when made of a metal bonding material).

[0061] According to the electrostatic chuck 1a of the present embodiment, heat transfer from the terminal member 70 to the low-temperature portion of the base member 20 can be promoted via the adhesive 26, the insulating sleeve 75, and the adhesive 76, so that the terminal member 70 (conductive member 71) can be effectively cooled. As a result, even at high temperatures, the resin connector 80 can be connected to the male terminal 71c provided at the other end of the conductive member 71, and a stable electrical connection between the external power supply and the electrostatic chuck 1a can be ensured via the connector 80.

[0062] 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, the terminal pad 60 and the heater electrode 52 are connected via the connection pad 63, but the terminal pad 60 and the heater electrode 52 may be directly connected by the via 61.

[0063] Furthermore, in the above embodiment, when a breathable metal bonding material (such as a metal mesh) is used as the bonding layer 40, it becomes impossible to ensure airtightness of the through-holes 30, such as the lift pin insertion holes 30a and the gas holes 30b. Therefore, as shown in Fig. 8, it is preferable to place an insulating sleeve 75 in the through-hole 30 and bond the insulating sleeve 75 to the base member 20 with an adhesive 76. This is because the airtightness of the through-hole 30 can be ensured.

[0064] Furthermore, in the above embodiment, metal is exemplified as the material for forming the base member 20, but the material is not limited to metal, and may be a material other than metal, such as ceramics (AlSiC, Si, etc.).

[0065] Furthermore, in the above embodiment, the plate-shaped member 10 and the base member 20 are bonded together with the bonding layer 40, but the plate-shaped member and the base member may be bonded together by diffusion bonding without using a bonding agent. In this case, too, since no bonding layer made of resin material is used, it can be used at high temperatures (for example, 250°C or higher). [Explanation of symbols]

[0066] 1. Electrostatic chuck 10 Plate-shaped member 11 Holding surface 12 Bottom side 20 Base member 21 Top side 22 Bottom side 23 Refrigerant flow path 23a Top side 25 through holes 26 Adhesive 35 Gap 40 Bonding layer 50 Chuck electrode 52 heater electrode 60 terminal pads 70 Terminal material 71 Conductive material 72 Ceramic materials 75 Insulating sleeve 76 Adhesive 77 Gap 80 Connector W Semiconductor wafer

Claims

1. a first member including a first surface, a second surface provided on the opposite side to the first surface, and a terminal pad provided on the second surface and connected to an internal electrode; a second member including a third surface, a fourth surface provided on the opposite side of the third surface, a through hole penetrating the third surface and the fourth surface, and a refrigerant flow path through which a refrigerant flows; a terminal member disposed inside the through hole, the terminal member including a conductive member having one end connected to the terminal pad, the other end connected to a connector, and a conductive portion connecting the one end and the other end; a bonding layer disposed between the second surface of the first member and the third surface of the second member to bond the first member and the second member, A holding device for holding an object on the first surface of the first member, the bonding layer is formed of an inorganic bonding material containing an inorganic material as a main component, the terminal member is disposed between the refrigerant flow paths of the second member, and the conducting portion is formed in a ceramic member; the one end is covered with the ceramic member, The conductive portion is integrally formed with the ceramic member in a sintered state. A holding device characterized by:

2. 2. The holding device according to claim 1, The terminal member is disposed on the fourth surface side of the upper surface that forms the refrigerant flow path, and the second member is joined to A holding device characterized by:

3. The holding device according to claim 1 or 2, A gap is formed between the terminal member and the through hole. A holding device characterized by:

4. 2. The holding device according to claim 1, the conductive member is brazed to the terminal pad, a cylindrical member disposed in the through hole so as to cover an outer periphery of the terminal member; The cylindrical member is integrally formed with the first member. A holding device characterized by:

5. 5. The holding device according to claim 4, A gap is formed between the cylindrical member and the through hole. A holding device characterized by:

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