JP7477389B2 - Retaining device - Google Patents

Description

The present invention relates to a holding device.

Electrostatic chucks are used as holding devices for holding wafers (e.g., silicon wafers) during semiconductor manufacturing. Electrostatic chucks have a ceramic plate-shaped member that contains a chuck electrode, and the wafer is attracted to the surface (attraction surface) of the plate-shaped member by utilizing the electrostatic attraction force that is generated when a voltage is applied to the chuck electrode. The electrostatic chuck also has a metal base member that is bonded to the back side of the plate-shaped member.

This type of electrostatic chuck also has multiple heaters for adjusting the temperature of the wafer attracted to the attraction surface. Each heater is provided inside the plate-shaped member, and the temperature of the wafer on the attraction surface can be adjusted by appropriately adjusting the heat generation of each heater. Furthermore, a refrigerant flow path (cooling mechanism) is provided inside the base member of the electrostatic chuck. The plate-shaped member joined to the base member is cooled by flowing a refrigerant such as cooling water through the refrigerant flow path.

In such an electrostatic chuck, since it is necessary to accurately detect the surface temperature of the plate-shaped member, multiple temperature measuring elements (thermistors, etc.) are provided on the plate-shaped member. The temperature measuring elements are provided, for example, dotted on the back side of the plate-shaped member. Some of these temperature measuring elements are provided near the cooling mechanism (coolant flow path) of the base member. Since heat is more likely to escape from the vicinity of the cooling mechanism than from other areas, the temperature measuring elements located there tend to detect lower temperatures than from other areas. Furthermore, if the temperature measuring elements are provided near through holes provided in the plate-shaped member or base member, the heat is poorly dissipated in those areas, so the temperature measuring elements located there tend to detect higher temperatures than from other areas. As a result, there is a possibility that the detected temperatures will vary among the multiple temperature measuring elements.

For these reasons and other reasons, electrostatic chucks have been provided in which a temperature measuring element is provided in a plate-like member so as to be positioned on the front side (upper side) of the heater (see, for example, Patent Documents 1 and 2). In this type of electrostatic chuck, the heater is located near the temperature measuring element, which prevents localized formation of areas near the temperature measuring element where heat can easily escape. The temperature measuring element is provided on the bottom surface of a recess (i.e., a recess with a shape that opens downwards) that is recessed from the back side of the plate-like member toward the front side.

JP 2018-60833 A JP 2018-60834 A

As described above, when a recess is formed in the plate-shaped member so that the temperature measuring element is positioned closer to the surface than the heater, it is necessary to provide wiring to connect to the temperature measuring element within the plate-shaped member so as to avoid such a recess. In other words, with conventional electrostatic chucks, there is a low degree of freedom in the direction in which the wiring to the temperature measuring element can be pulled out, which poses a problem.

The object of the present invention is to provide a holding device that allows a high degree of freedom in the direction in which the wiring connected to the temperature measuring element is pulled out.

The means for solving the above problems are as follows.
<1> A holding device comprising: a first plate-shaped member having a plate-like shape including a first surface and a second surface substantially perpendicular to a first direction; a plurality of heaters arranged inside the first plate-shaped member or on the second surface; a plurality of temperature measuring elements arranged on the first plate-shaped member; a holding substrate having temperature measuring element terminals connected to the temperature measuring elements via wiring; and a base member arranged on the second surface side and having a cooling mechanism, wherein the temperature measuring elements are located on the first surface side of the heater in the first direction, and the wiring is arranged inside the first plate-shaped member and is pulled out from the temperature measuring elements toward the heater side.

<2> The holding device described in <1>, wherein the first plate-like member is a storage section formed on the first surface, the storage section including a bottom where the temperature measuring element is arranged, a peripheral wall rising from the periphery of the bottom toward the first surface side and surrounding the bottom, and an opening formed by the end of the peripheral wall on the first surface side.

<3> The holding device described in <1> or <2>, wherein the holding substrate includes a third surface and a fourth surface that are substantially perpendicular to the first direction, a second plate-like member that is arranged such that the fourth surface faces the first surface in the first direction, and a joint that joins the first plate-like member and the second plate-like member.

<4> The holding device described in <2> above, which has a lid arranged to cover the opening in the first plate-like member.

<5> The holding device according to any one of <1>1 to <4>, in which the temperature measuring elements are positioned differently in the first direction.

The present invention provides a holding device that allows a high degree of freedom in the direction in which the wiring connected to the temperature measuring element is pulled out.

FIG. 1 is a perspective view showing an external configuration of an electrostatic chuck according to a first embodiment; FIG. 1 is an explanatory diagram illustrating a cross-sectional configuration of a portion of an electrostatic chuck according to a first embodiment; An enlarged cross-sectional view of a temperature sensor installed in a plate-shaped member. An enlarged cross-sectional view of a connector installed in a base member. FIG. 11 is an explanatory diagram illustrating a schematic cross-sectional configuration of a portion of an electrostatic chuck according to a second embodiment; FIG. 11 is an explanatory diagram illustrating a cross-sectional configuration of a portion of an electrostatic chuck according to a third embodiment; FIG. 13 is an enlarged cross-sectional view of a temperature measuring element installed in a plate-shaped member of an electrostatic chuck according to a fourth embodiment.

<Embodiment 1>
A holding device according to a first embodiment of the present invention will be described below with reference to FIGS. 1 to 4. In this embodiment, an electrostatic chuck 100 is illustrated as an example of a holding device. FIG. 1 is a perspective view that shows a schematic external configuration of the electrostatic chuck 100 according to the first embodiment, and FIG. 2 is an explanatory view that shows a schematic cross-sectional configuration of a part of the electrostatic chuck 100 according to the first embodiment. Each figure shows mutually orthogonal X, Y and Z axes for specifying directions. In this specification, for convenience of explanation, the Z-axis direction may be referred to as a "first direction", a "vertical direction", etc., and a direction perpendicular to the Z-axis direction may be referred to as a "planar direction", etc. FIG. 2 shows a cross-sectional configuration of the electrostatic chuck 100 cut in the first direction.

The electrostatic chuck 100 is a device that attracts and holds an object (e.g., a wafer W) by electrostatic attraction, and is used, for example, to fix the wafer W in a vacuum chamber of a semiconductor manufacturing device. The electrostatic chuck 100 mainly comprises a holding substrate 10 and a base member 20. The holding substrate 10 and the base member 20 are arranged side by side in the vertical direction (first direction) via a joint 30.

The joint 30 is made of an adhesive such as silicone resin, acrylic resin, or epoxy resin.

The holding substrate 10 is generally disk-shaped and includes a substantially circular planar surface (adsorption surface) S1 and a back surface S2 extending in a direction substantially perpendicular to the up-down direction (first direction). The back surface S2 is disposed on the opposite side of the surface S1, and the surface S1 functions as an adsorption surface on which the wafer W is placed when adsorbing it. Note that the surface (adsorption surface) S1 may be provided with a convex portion or a concave portion as necessary.

The diameter of the holding substrate 10 is, for example, about 50 mm to 500 mm (usually about 200 mm to 350 mm), and the thickness of the holding substrate 10 is, for example, about 1 mm to 20 mm.

The holding substrate 10 includes a first plate-shaped member 11 (hereinafter, plate-shaped member 11) and a second plate-shaped member 12 (hereinafter, plate-shaped member 12) arranged side by side in the vertical direction (first direction). The plate-shaped member 11 is arranged below the plate-shaped member 12. The plate-shaped members 11 and 12 are made of alumina sintered bodies whose main component is alumina.

The plate-like member 11 is a plate-like member including a first surface 11a and a second surface 11b that are substantially perpendicular to the up-down direction (first direction). The first surface 11a is disposed on the upper side of the plate-like member 11, and the second surface 11b is disposed on the lower side of the plate-like member 11. The second surface 11b of the plate-like member 11 constitutes the rear surface S2 of the holding substrate 10.

The plate-shaped member 12 includes a third surface 12a and a fourth surface 12b that are substantially perpendicular to the vertical direction (first direction), and is a plate-shaped member having a smaller thickness than the plate-shaped member 11. The third surface 12a is disposed on the upper side of the plate-shaped member 12, and the fourth surface 12b is disposed on the lower side of the plate-shaped member 12. The third surface 12a of the plate-shaped member 12 constitutes the surface (adsorption surface) S1 of the holding substrate 10. The plate-shaped member 12 is disposed so that the fourth surface 12b faces the first surface 11a of the plate-shaped member 11 in the vertical direction (first direction). The plate-shaped member 12 is fixed to the upper side of the plate-shaped member 11 via a joint 31. The joint 31 is formed of the same adhesive as the joint 30. An O-ring 32 made of silicone rubber or the like is disposed around the joint 31, and the O-ring 32 is also sandwiched between the plate-shaped member 11 and the plate-shaped member 12 and is interposed therebetween.

A chuck electrode 40, a plurality of heaters 50, a plurality of temperature measuring elements 60, etc. are arranged inside the holding substrate 10. The chuck electrode 40 is arranged inside the plate-shaped member 12, and the heaters 50, the temperature measuring elements 60, etc. are arranged inside the plate-shaped member 11.

The chuck electrode 40 is made of a conductive material (e.g., tungsten, molybdenum, platinum, etc.). The chuck electrode 40 has a substantially circular shape when viewed from above and below (when viewed from a first direction). When a high DC voltage is applied to the chuck electrode 40 from a power source (not shown), an electrostatic force is generated, and the wafer W is attracted and fixed to the surface S1 of the holding substrate 10 by this electrostatic force. The chuck electrode 40 is electrically connected to a well-known power supply terminal (not shown).

The holding substrate 10 is provided with a plurality of heaters 50 for controlling the temperature distribution of the surface (adsorption surface) S1 (i.e., controlling the temperature distribution of the wafer W held on the surface S1). The heaters 50 are made of a conductive material (e.g., aluminum, nickel, copper, stainless steel, etc.) processed into layers, and are disposed inside the plate-like member 11.

The heater 50 has a linear heating portion 51 that generates heat when a voltage is applied and a current flows through it. A pair of wirings 52, 53 are connected to the heating portion 51. These wirings 52, 53 are formed by vias that extend in the thickness direction (vertical direction) of the plate-like member 11 and internal wiring layers that extend in the planar direction.

The holding substrate 10 has a plurality of concentric heating regions in a plan view (viewed in the first direction), and heaters 50 (heat generating portions 51) are arranged so that they are assigned to each heating region. The heaters 50 are arranged on a virtual plane within the plate-like member 11 of the holding substrate 10. A well-known power supply terminal (not shown) is electrically connected to each heater 50.

The temperature measuring element 60 is, for example, a thermistor whose resistance value changes depending on the temperature, and is placed in a position overlapping the heating area. The temperature measuring element 60 will be described later.

The base member 20 is a substantially circular, flat, plate-like member with the same diameter as the holding substrate 10 or a larger diameter than the holding substrate 10, and is made of, for example, a metal (aluminum, aluminum alloy, etc.). The base member 20 is joined to the holding substrate 10 by a joint 30 disposed between the back surface S2 of the holding substrate 10 and the front surface S3 of the base member 20. The back surface S4 is disposed on the opposite side of the front surface S3 of the base member 20. The diameter of the base member 20 is, for example, about 220 mm to 550 mm (usually about 220 mm to 350 mm), and the thickness of the base member 20 is, for example, about 20 mm to 40 mm.

A refrigerant flow path (cooling mechanism) 24 is provided inside the base member 20. When a refrigerant (e.g., a fluorine-based inert liquid, water, etc.) flows through the refrigerant flow path 24, the base member 20 is cooled, and the holding substrate 10 is cooled by heat transfer (heat withdrawal) between the base member 20 and the holding substrate 10 via the joint 30, and the wafer W held on the surface S1 of the holding substrate 10 is cooled. This allows control of the temperature distribution of the wafer W.

3 is an enlarged cross-sectional view of the temperature measuring element 60 installed in the plate-shaped member 11. The first surface 11a of the plate-shaped member 11 has a plurality of recessed storage sections 13 formed therein, and the temperature measuring element 60 is installed in the storage section 13. The storage section 13 includes a bottom section 13a on which the temperature measuring element 60 is arranged, a peripheral wall section 13b that rises from the periphery of the bottom section 13a toward the first surface 11a side and surrounds the bottom section 13a, and an opening section 13c formed by the end of the peripheral wall section 13b on the first surface 11a side. The storage sections 13 have the same shape and size. The bottom section 13a of each storage section 13 is arranged on the first surface 11a side (upper side) of the heater 50 in the first direction. Therefore, the temperature measuring element 60 arranged on the bottom section 13a is also arranged on the first surface 11a side (upper side) of the heater 50.

The housing section 13 is not formed so as to exceed (straddle) the position where the heater 50 is arranged in the vertical direction. Therefore, the portion of the plate-shaped member 11 below the temperature measuring element 60 can be made of a single piece of ceramic.

As shown in FIG. 3, the temperature sensor 60 is composed of a thermistor sintered body 61 and a pair of platinum electrode wires 62 (62a, 62b) extending from the thermistor sintered body 61. One electrode wire 62a is the positive side, and the other electrode wire 62b is the negative side.

The temperature sensor 60 is housed in a recessed housing 13 that opens upward. A pair of electrode pads 63 are formed on the bottom 13a of the housing 13, and an electrode wire 62 is joined to the electrode pads 63, for example, by brazing. The inside of the housing 13 is filled with a filler 31a made of a part of the joint 31 so that there are no gaps.

A pair of wirings 57a, 57b are connected to each temperature measuring element 60. One of the wirings 57a is composed of a via 57a1 extending from an electrode pad 63 connected to the positive electrode wire 62a toward the lower side (second surface 11b side) in the thickness direction (vertical direction) of the plate-like member 11, an internal wiring layer 57a2 extending in the planar direction from the lower end of the via 57a1, and a via 57a3 extending in the thickness direction (vertical direction) of the plate-like member 11 from the internal wiring layer 57a2 toward a connector 71 (an example of a temperature measuring element terminal) on the lower side (second surface 11b side). Each wiring 57a of each temperature measuring element 60 is electrically connected separately to a plurality of connection parts 84 housed in one connector 71.

The other wiring 57b is composed of a via 57b1 that extends from the electrode pad 63 connected to the negative electrode wire 62b toward the lower side (second surface 11b side) in the thickness direction (vertical direction) of the plate-like member 11, an internal wiring layer 57b2 that extends in the planar direction from the lower end of the via 57b1, and a via 57b3 that extends from the internal wiring layer 57b2 toward the connector 71 (an example of a temperature measuring element terminal) on the lower side (second surface 11b side) in the thickness direction (vertical direction) of the plate-like member 11. Each wiring 57b of each temperature measuring element 60 is electrically connected separately to a plurality of connection parts 84 housed in one connector 71.

Figure 4 is an enlarged cross-sectional view of the connector 71 installed in the base member 20. The base member 20 and the joint portion 30 have an internal hole 21 formed to penetrate in the vertical direction, and a plurality of electrode pads 81 are provided on the second surface 11b of the plate-like member 11 exposed from the internal hole 21. The positive wiring 57a and the negative wiring 57b of each temperature measuring element 60 are connected to the upper surface of each electrode pad 81. In addition, a pin-shaped terminal portion 82 is provided on the lower surface of each electrode pad 81. The electrode pads 81 and the terminal portions 82 are connected by brazing or the like.

The connector 71 has a resin tip connector part 71a that is located on the upper side (surface S3 side) of the internal hole 21, a resin rear end connector part 71b that is located on the lower side (back surface S4 side) of the internal hole 21, and a cable part 71c that connects the tip connector part 71a and the rear end connector part 71b.

The tip connector portion 71a is a substantially rectangular parallelepiped, and a plurality of connection portions 84 are formed on its tip surface 71a1, each of which has an elongated terminal hole 83 into which a pin-shaped terminal portion 82 is inserted. Each connection portion 84 is formed from a conductive material that surrounds the terminal hole 83 and extends toward the cable portion 71c.

The rear end connector section 71b has the same basic configuration as the front end connector section 71a, and is provided with a number of connection sections 86, each of which has a long and narrow terminal hole 85. Each connection section 84 of the front end connector section 71a and each connection section 86 of the rear end connector section 71b are electrically connected to each other by each conductor 87 of the cable section 71c.

By pushing the tip connector portion 71a of such a connector 71 into the internal hole 21, each terminal portion 82 and each connection portion 84 (terminal portion hole 83) are connected, and electrical continuity is obtained.

In the electrostatic chuck 100 of this embodiment, the wiring 57a, 57b is disposed inside the plate-shaped member 11 and is pulled out from the temperature measuring element 60 toward the heater 50. In this way, the electrostatic chuck 100 of this embodiment has a structure that allows a high degree of freedom in the pull-out direction of the wiring 57a, 57b connected to the temperature measuring element 60.

In addition, in the electrostatic chuck 100 of this embodiment, a location for the heater 50 and an internal conductive layer (driver, etc.) connected to the heater 50, etc. can be secured below the temperature measuring element 60, allowing for greater freedom in the design of the heater 50 and the internal conductive layer.

In the electrostatic chuck 100 of this embodiment, the plate-shaped member 11 has a housing portion 13 that opens upward to house the temperature measuring element 60. The housing portion 13 is disposed closer to the first surface 11a than the heater 50 in the vertical direction, and the temperature measuring element 60 disposed on the bottom 13a of the housing portion 13 is disposed closer to the first surface 11a than the heater 50. Therefore, in this embodiment, there is no need to form a recess for housing the temperature measuring element 60 below the temperature measuring element 60 (bottom 13a), and the portion below the temperature measuring element 60 (bottom 13a) (second surface 11b side) can be made of a single ceramic. Wiring 57a, 57b can be disposed in such a portion.

In the electrostatic chuck 100 of this embodiment, the holding substrate 10 includes a plate-shaped member 12, which is joined to the plate-shaped member 11 via a joint 31 so as to cover the temperature measuring element 60 housed in the housing portion 13. The temperature measuring element 60 in the housing portion 13 is covered with a filler 31a consisting of a part of the joint 31, and the temperature measuring element 60 in such a state is covered by the plate-shaped member 12. Therefore, during plasma etching or the like, the filler 31a is deteriorated, and the generation of particle-like foreign matter is suppressed. In particular, an O-ring 32 is interposed between the plate-shaped member 12 and the plate-shaped member 11, and deterioration of the joint 31 between the plate-shaped member 12 and the plate-shaped member 11 is suppressed.

<Embodiment 2>
Next, an electrostatic chuck (holding device) 100B according to a second embodiment will be described with reference to Fig. 5. Fig. 5 is an explanatory diagram that shows a schematic cross-sectional configuration of a portion of the electrostatic chuck 100B according to the second embodiment. The basic configuration of the electrostatic chuck 100B according to the second embodiment is the same as that of the first embodiment. Therefore, in Fig. 5, parts corresponding to those of the first embodiment are denoted by the same reference numerals as those of the first embodiment with the addition of the reference numeral "B", and detailed description thereof will be omitted.

In the electrostatic chuck 100B of this embodiment, a chuck electrode 40B is provided in the plate-shaped member 11B of the holding substrate 10B. The surface SB1 of the holding substrate 10B is made of the first surface 11Ba of the plate-shaped member 11B, and the back surface SB2 of the holding substrate 10B is made of the second surface 11Bb of the plate-shaped member 11B. A plurality of storage sections 13B for storing the temperature measuring elements 60B are formed on the first surface 11Ba of the plate-shaped member 11B. The storage section 13B is provided with a bottom 13Ba in which the temperature measuring elements 60B are arranged, a peripheral wall section 13Bb that rises from the periphery of the bottom 13Ba toward the first surface 11Ba and surrounds the bottom 13Ba, and an opening 13Bc formed by the end of the peripheral wall section 13Bb on the first surface 11Ba side. On the opening 13Bc side of the peripheral wall 13Bb, there is a step 13Bb1 that includes a peripheral wall with a larger inner diameter than the bottom 13Ba side and includes an annular surface on which the O-ring 81 is placed.

A lid 80 is arranged to close the opening 13Bc of the storage section 13B when the temperature measuring element 60B is stored therein. An O-ring 81 made of silicone resin or the like is placed on the step 13Bb1, and the opening 13Bc is closed when the lid 80 is placed on the O-ring 81. The lid 80 is made of a ceramic material, similar to the plate-shaped member 11B. The inside of the storage section 13B is filled with a filler 82, and the back side (lower side) of the lid 80 is fixed in contact with the filler 82. The filler 82 is made of the same material as the joint section 30B, for example.

In this embodiment, the wiring 57Ba, 57Bb of the electrostatic chuck 100B is pulled out from the temperature measuring element 60B toward the heater 50B, providing a structure with a high degree of freedom in the direction in which the wiring 57Ba, 57Bb is pulled out.

In addition, in the electrostatic chuck 100B of this embodiment, a location for the heater 50B and an internal conductive layer (driver, etc.) connected to the heater 50B can be secured below the temperature measuring element 60B, allowing for greater freedom in the design of the heater 50B and the internal conductive layer.

The plate-like member 11B of this embodiment has a storage section 13B that opens upward to store the temperature measuring element 60B. The storage section 13B is arranged closer to the first surface 11Ba than the heater 50B in the vertical direction, and the temperature measuring element 60B arranged on the bottom 13Ba of the storage section 13B is arranged closer to the first surface 11Ba than the heater 50B. In this embodiment, there is no need to form a recess below the temperature measuring element 60B (bottom 13Ba) to store the temperature measuring element 60B, and the portion below the temperature measuring element 60B (bottom 13Ba) (second surface 11Bb side) can be made of a single piece of ceramic. Wiring 57Ba, 57Bb can be arranged in such a portion.

The electrostatic chuck 100B of this embodiment also includes a lid 80 that closes the opening 13Bc of the accommodation portion 13B formed in the plate-shaped member 11B. The lid 80 is fixed to the plate-shaped member 11B via the filler 82 filled in the accommodation portion 13B so as to cover the temperature measuring element 60B accommodated in the accommodation portion 13B. This prevents the filler 82 from deteriorating and generating particle-like foreign matter during plasma etching and the like. In particular, an O-ring 81 is provided for each accommodation portion 13B, preventing the filler 82 in the accommodation portion 13B from deteriorating and the like.

<Embodiment 3>
Next, an electrostatic chuck (holding device) 100C according to a third embodiment will be described with reference to Fig. 6. Fig. 6 is an explanatory diagram that shows a schematic cross-sectional configuration of a portion of the electrostatic chuck 100C according to the third embodiment. The basic configuration of the electrostatic chuck 100C according to the present embodiment is the same as that of the first embodiment. Therefore, in Fig. 6, parts corresponding to those of the first embodiment are denoted by the same reference numerals as those of the first embodiment with the addition of the reference numeral "C", and detailed description thereof will be omitted.

In the electrostatic chuck 100C of this embodiment, similarly to the first embodiment, a plurality of temperature measuring elements 60C are arranged one by one in a plurality of accommodation sections 13C provided in the plate-like member 11C. The accommodation sections 13C are arranged closer to the first surface 11Ca than the heater 50C in the vertical direction, and the temperature measuring elements 60C arranged on the bottom 13Ca of such accommodation sections 13C are arranged closer to the first surface 11Ca than the heater 50C. However, in this embodiment, the positions of the accommodation sections 13C in the vertical direction are different from each other, and the temperature measuring elements 60C arranged on the bottom 13Ca of such accommodation sections 13C are different from each other in the vertical direction (first direction).

For example, the storage section 13C1 shown on the far left side of FIG. 7 is positioned closest to the first surface 11Ca in the vertical direction, and storage sections 13C2 and 13C4, which are positioned to the right of storage section 13C1, are positioned closest to the heater 50C in the vertical direction. Storage section 13C3 is positioned between storage sections 13C1 and 13C2, etc., in the vertical direction.

The wiring 57Ca, 57Cb connected to each temperature measuring element 60C is pulled out from each of the wiring 57Ca, 57Cb toward the heater 50C, as in the first embodiment. In this manner, the wiring 57Ca, 57Cb of the electrostatic chuck 100C of this embodiment is pulled out from the temperature measuring element 60C toward the heater 50C, and the structure provides a high degree of freedom in the pull-out direction of the wiring 57Ca, 57Cb.

In addition, in the electrostatic chuck 100C of this embodiment, a location for the heater 50C and an internal conductive layer (driver, etc.) connected to the heater 50C, etc. can be secured below the temperature measuring element 60C, allowing for greater freedom in the design of the heater 50C and the internal conductive layer.

In the case of this embodiment, there is no need to form a recess below the temperature measuring element 60C (bottom 13Ca) to accommodate the temperature measuring element 60C, and the portion below the temperature measuring element 60C (bottom 13Ca) (second surface 11Cb side) can be made of a single piece of ceramic. Wiring 57Ca, 57Cb can be arranged in such a portion.

<Embodiment 4>
Next, an electrostatic chuck (holding device) 100D according to a fourth embodiment will be described with reference to Fig. 7. Fig. 7 is an enlarged cross-sectional view of a temperature measuring element 60D installed in a plate-shaped member 11D of an electrostatic chuck 100D according to a fifth embodiment. The basic configuration of the electrostatic chuck 100D of this embodiment is the same as that of the third embodiment. Therefore, in Fig. 7, the parts corresponding to those of the third embodiment are denoted by reference characters "D" instead of "C" of the third embodiment, and detailed description thereof will be omitted.

In the electrostatic chuck 100D of this embodiment, a chuck electrode (not shown) is provided in the plate-shaped member 11D of the holding substrate 10D. The surface SD1 of the holding substrate 10D is made of the first surface 11Da of the plate-shaped member 11D, and the back surface (not shown) of the holding substrate 10D is made of the second surface (not shown) of the plate-shaped member 11. A plurality of storage sections 13D for storing the temperature measuring elements 60D are formed on the first surface 11Da of the plate-shaped member 11D. The storage section 13D is provided with a bottom 13Da on which the temperature measuring elements 60D are arranged, a peripheral wall section 13Db that rises from the periphery of the bottom 13Da toward the first surface 11Da and surrounds the bottom 13Da, and an opening 13Dc formed of the end of the peripheral wall section 13Db on the first surface 11Da side. The opening 13Dc side of the peripheral wall 13Db includes a peripheral wall with a larger inner diameter than the bottom 13Da side, and a step 13Db1 is provided that includes an annular surface on which the lid 80D is placed.

A lid 80D is arranged to close the opening 13Dc of the storage section 13D when the temperature measuring element 60D is stored. The periphery of the lid 80D is placed on the step 13Db1, so that the opening 13Dc is closed by the lid. An O-ring 81D made of silicone resin or the like is stored inside the storage section 13B so as to surround the temperature measuring element 60D. The O-ring 81D is sandwiched between the lid 80D and the bottom 13Da. The inside of the storage section 13D is filled with a filler 82D, which is mainly filled inside the O-ring 81D. The back side (lower side) of the lid 80D is fixed in contact with the filler 82D inside the storage section 13D.

The wiring 57Da, 57Db of the electrostatic chuck 100D of this embodiment is pulled out from the temperature measuring element 60D toward the heater (not shown), providing a high degree of freedom in the direction in which the wiring 57Da, 57Db are pulled out.

In addition, in the electrostatic chuck 100D of this embodiment, a location for a heater or an internal conductive layer (driver, etc.) connected to the heater can be secured below the temperature measuring element 60D, allowing for greater freedom in the design of the heater 50 and the internal conductive layer.

The plate-like member 11D of this embodiment has a storage section 13D that opens to the top for storing the temperature measuring element 60D. The storage section 13D is arranged on the first surface 11Da side of the heater (not shown) in the vertical direction, and the temperature measuring element 60D arranged on the bottom 13Da of such a storage section 13D is arranged on the first surface 11Da side of the heater (not shown). In the case of this embodiment, there is no need to form a recess for storing the temperature measuring element 60D below the temperature measuring element 60D (bottom 13Da), and the part below the temperature measuring element 60D (bottom 13Da) (second surface side) can be made of a single ceramic. Wiring 57Da, 57Db can be arranged in such a part.

<Other embodiments>
The present invention is not limited to the embodiments described above and illustrated in the drawings, and the following embodiments, for example, are also included within the technical scope of the present invention.

(1) In the above embodiment, the heaters are disposed within the first plate-shaped member, but the present invention is not limited to this. In other embodiments, the heaters may be disposed on the second surface of the plate-shaped member.

(2) In addition to thermistors, platinum resistance thermometers and other devices can be used as temperature measuring elements.

(3) In each embodiment, the electrode wire of the temperature measuring element is brazed to the electrode pad, but a pinhole-like structure may be provided on the electrode pad side so that the electrode wire can be inserted into the pinhole. Note that the method of connecting the temperature measuring element and the electrode pad on the plate-shaped member is not limited to these, and any method is acceptable as long as it does not impair the purpose of the present invention.

(4) In the above embodiment 1, etc., the chuck electrode is provided in the second plate-like member, but in other embodiments, the chuck electrode may be provided in the first plate-like member without being provided in the second plate-like member.

(5) In other embodiments, the multiple negative wirings connected to each temperature measuring element may be combined into a single common internal wiring layer, as long as this does not impair the objective of the present invention.

10...holding substrate, 11...first plate-like member, 11a...first surface, 11b...second surface, 12...second plate-like member, 13...accommodation section, 13a...bottom, 13b...peripheral wall, 13c...opening, 20...base member, 24...cooling mechanism (coolant flow path), 30...joint, 31...joint, 32...O-ring, 40...chuck electrode, 50...heater, 57a, 57b...wiring, 60...temperature measuring element, 71...connector (temperature measuring element terminal), 100...holding device (electrostatic chuck)

Claims (4)

a first plate-like member having a plate shape including a first surface and a second surface substantially perpendicular to a first direction, a plurality of heaters disposed inside the first plate-like member or on the second surface, a plurality of temperature measuring elements disposed on the first plate-like member, and a holding substrate having temperature measuring element terminals connected to the temperature measuring elements via wiring;
a base member disposed on the second surface side and having a cooling mechanism,
the temperature measuring element is located closer to the first surface than the heater in the first direction,
the wiring is disposed inside the first plate-like member and is drawn out from the temperature measuring element toward the heater side ;
The first plate-shaped member is a holding device having a storage portion formed on the first surface, the storage portion including a bottom portion on which the temperature measuring element is placed, a peripheral wall portion that rises from the periphery of the bottom portion toward the first surface side and surrounds the bottom portion, and an opening formed by the end portion of the peripheral wall portion on the first surface side . The holding substrate is
a second plate-like member including a third surface and a fourth surface substantially perpendicular to the first direction, the fourth surface being disposed so as to face the first surface in the first direction;
The holding device according to claim 1 , further comprising: a joint portion that joins the first plate-like member and the second plate-like member. The holding device according to claim 1 , further comprising a cover member arranged to cover the opening in the first plate-like member. The holding device according to claim 1 , wherein the temperature measuring elements are arranged at different positions in the first direction.

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