JP2017163019A - Retainer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a retainer capable of controlling reduction of uniformity in a temperature distribution of a first surface of an insulation plate.SOLUTION: In an electrostatic chuck 100, a heater 50 includes: a first heater wire 510 that is extended from one direction of a pair of first terminal parts to the other direction; a second heater wire 520 that is extended from one direction of a pair of second terminal parts to the other direction; and a third heater wire 530 that is extended from one direction of a pair of third terminal parts to the other direction, in which one of the pair of the third terminal parts is electrically connected to one of the pair of second terminal parts, and the other of the pair of the third terminal parts is electrically connected to the other of the pair of the second terminal parts. At least one part of the second heater wire is arranged at a position closer than the third heater wire to one line part of the fist heater wire. At least one part of the third heater wire is arranged at the position closer than the second heater wire to the other line part of the first heater wire in which the position in a second direction that the first heater wire is extended is different from one line part.SELECTED DRAWING: Figure 3

Description

  The technology disclosed in this specification relates to a holding device that holds an object.

  For example, in a semiconductor manufacturing apparatus, an electrostatic chuck is used as a holding device that holds a wafer. The electrostatic chuck has a configuration in which, for example, a ceramic plate made of ceramics and a base plate are joined. The electrostatic chuck has an internal electrode, and attracts the wafer to the surface of the ceramic plate (hereinafter referred to as “adsorption surface”) by using electrostatic attraction generated by applying a voltage to the internal electrode. And hold.

  If the temperature distribution of the wafer held on the electrostatic chuck becomes non-uniform, the accuracy of each process (film formation, etching, exposure, etc.) on the wafer will be reduced. Performance is required. For this reason, a heater is provided inside the ceramic plate or on the base plate side of the ceramic plate. When the electrostatic chuck is used, the temperature of the adsorption surface of the ceramic plate is controlled by heating with the heater. For example, the heater includes a spiral heater wire having one end electrically connected to one of the pair of power supply terminals and the other end electrically connected to the other of the pair of power supply terminals (see Patent Document 1). .

JP 2014-75525 A

  In order to improve the uniformity of the temperature distribution on the adsorption surface of the ceramic plate, it is preferable that the cross-sectional area perpendicular to the extension direction of the heater wire (hereinafter referred to as “cross-sectional area”) is uniform. However, the cross-sectional area of the heater wire may become non-uniform due to, for example, variations in forming pressure when the heater wire is formed. The portion of the heater wire located in the region where the received pressure is high has a relatively large cross-sectional area and thus has a high resistance. On the other hand, the portion of the heater wire located in the region where the received pressure is low has a relatively small cross-sectional area and thus has a low resistance. For this reason, in the above-described spiral heater wire, the portion of the heater wire located in the region where the received pressure is high generates a large amount of heat, and the portion of the heater wire located in the region where the received pressure is low has a small amount of heat generation. As a result, the uniformity of the temperature distribution on the adsorption surface of the ceramic plate may be reduced.

  Such a problem is not limited to an electrostatic chuck that holds a wafer using electrostatic attraction, but is a problem common to a holding device that holds an object on the surface side of an insulating plate, such as a polyimide heater. .

  In this specification, the technique which can solve the subject mentioned above is disclosed.

  The technology disclosed in the present specification can be realized as, for example, the following forms.

(1) A holding device disclosed in the present specification includes a plate-shaped insulating plate having a first surface and a second surface opposite to the first surface, and an interior of the insulating plate. Or a heater disposed on the second surface side of the insulating plate, and a holding device for holding an object on the first surface side of the insulating plate, wherein the heater has a pair of first A pair of first ends, a first heater wire extending from one of the pair of first ends to the other, a pair of second ends, and the pair of second ends A second heater wire extending from one side to the other and a pair of third ends, extending from one of the pair of third ends to the other, and the pair of thirds One end of the pair is electrically connected to one of the pair of second ends, and the other of the pair of third ends is the other of the pair of second ends A third heater wire electrically connected, and in a first direction perpendicular to the first surface of the insulating plate, with respect to one line portion of the first heater wire, At least a part of the second heater line is disposed closer to the third heater line, and the position in the second direction in which the first heater line extends is different from the one line part. At least a portion of the third heater line is disposed closer to the second heater line than another line portion of the first heater line. In this holding device, for example, when the resistance of one line portion of the first heater line is higher than the resistance of another line portion, the heat generation amount of the one line portion is larger than the heat generation amount of the other line portion. On the other hand, since the second heater wire and the third heater wire are electrically connected in parallel, for example, when the resistance of the second heater wire is higher than the resistance of the third heater wire, The amount of heat generated by the heater wire is smaller than the amount of heat generated by the third heater wire. Then, the lines arranged closer to each other tend to have a smaller difference in cross-sectional area perpendicular to the extension direction of the lines (hereinafter simply referred to as “cross-sectional area”). In the holding device, at least a part of the second heater line is arranged closer to the third heater line than the first heater line, and another line part of the first heater line is arranged on the other part of the first heater line. On the other hand, at least a part of the third heater line is disposed closer to the second heater line. As a result, for example, when the resistance of one line portion of the first heater line and at least a portion of the second heater line is relatively high, the heat generation amount of the one line portion of the first heater line is relatively high. However, the amount of heat generated by the second heater wire is relatively small. In addition, when the resistance of another line portion of the first heater wire and at least a part of the third heater wire is relatively high, the heat generation amount of the other wire portion of the first heater wire is relatively large. The amount of heat generated by the third heater wire is relatively small. Thereby, it can suppress that the uniformity of the temperature distribution of the 1st surface of an insulating board resulting from the variation in the cross-sectional area of a heater wire falls.

(2) In the holding device, when the first direction is viewed, one of two regions partitioned by an imaginary line orthogonal to the first heater wire in the insulating plate includes the second region. A configuration in which a heater wire is disposed, the third heater wire is not disposed, and the second heater wire is not disposed in the other region, and the third heater wire is disposed. It is good. According to the present holding device, the second heater wire partly extends to the other region, or the third heater wire partly extends to one region, compared with the case where the insulating plate It can suppress more effectively that the uniformity of the temperature distribution of 1 surface falls.

(3) In the holding device, the second direction is a direction around the center of the insulating plate, and the first heater wire extends along the second direction as viewed in the first direction. An extending annular shape may be configured, and the combination of the second heater wire and the third heater wire may constitute at least a part of an annular shape having a diameter different from that of the first heater wire. According to this holding device, since the heater has an annular shape, the uniformity of the temperature distribution on the first surface of the insulating plate can be improved.

(4) In the holding device, as viewed in the first direction, the second heater wire extends from one of the pair of second ends to one side in the second direction and is folded back to the other side. And the third heater wire extends from one side of the pair of third ends to the other side in the second direction while being connected to the other side of the pair of second ends. A shape that is folded back to the other of the pair of third ends may be configured. Since both ends of the second heater wire and both ends of the third heater wire can be arranged close to each other, a structure for electrically connecting the second heater wire and the third heater wire is provided. It can be simplified.

(5) In the holding device, in the first direction view, the first heater wire includes an inner peripheral side and an outer peripheral side of the second heater wire and the third heater wire that form an annular shape. A shape extending from one of the pair of first end portions so as to surround both sides of the pair of first end portions may be formed. According to this holding device, the structure for electrically connecting to the power source can be simplified while arranging the first heater wire in a wide range.

(6) In the holding device, the first heater wire, the second heater wire, and the third heater wire in the first direction view, the second heater forming an annular shape. It is good also as a structure arrange | positioned alternately by the direction which goes to the outer peripheral side from the inner peripheral side of a wire and a said 3rd heater wire. According to the present holding device, the uniformity of the temperature distribution can be improved over a wide range of the first surface of the insulating plate.

  The technology disclosed in this specification can be realized in various forms, for example, in the form of a holding device, an electrostatic chuck, a manufacturing method thereof, and the like.

1 is a perspective view schematically showing an external configuration of an electrostatic chuck 100 according to a first embodiment. It is explanatory drawing which shows roughly the XZ cross-sectional structure of the electrostatic chuck 100 in 1st Embodiment. It is explanatory drawing which shows roughly the XY cross-sectional structure of the electrostatic chuck 100 in 1st Embodiment. 5 is a schematic diagram showing a wiring relationship between a first large heater line 511, a second large heater line 521, and a third large heater line 531. FIG. It is explanatory drawing which shows XY cross-sectional structure of the electrostatic chuck 100a in 2nd Embodiment. It is explanatory drawing which shows XY cross-sectional structure of the electrostatic chuck 100b in 3rd Embodiment.

A. First embodiment:
A-1. Configuration of the electrostatic chuck 100:
FIG. 1 is a perspective view schematically showing an external configuration of the electrostatic chuck 100 in the present embodiment, and FIG. 2 is an explanatory diagram schematically showing an XZ sectional configuration of the electrostatic chuck 100 in the present embodiment. FIG. 3 is an explanatory diagram schematically showing an XY cross-sectional configuration of the electrostatic chuck 100 according to the present embodiment. 2 shows an XZ sectional configuration of the electrostatic chuck 100 at the position II-II in FIG. 3, and FIG. 3 shows an XY sectional configuration of the electrostatic chuck 100 at the position III-III in FIG. It is shown. In each figure, XYZ axes orthogonal to each other for specifying the direction are shown. In this specification, for convenience, the positive direction of the Z-axis is referred to as the upward direction, and the negative direction of the Z-axis is referred to as the downward direction. However, the electrostatic chuck 100 is actually installed in a direction different from such a direction. May be.

  The electrostatic chuck 100 is a device that attracts and holds an object (for example, a wafer W) by electrostatic attraction, and is used, for example, to fix the wafer W in a vacuum chamber of a semiconductor manufacturing apparatus. The electrostatic chuck 100 includes a ceramic plate 10 and a base plate 20 that are arranged in a predetermined arrangement direction (in this embodiment, the vertical direction (Z-axis direction)). The ceramic plate 10 and the base plate 20 are such that the lower surface of the ceramic plate 10 (hereinafter referred to as “ceramic side adhesive surface S2”) and the upper surface of the base plate 20 (hereinafter referred to as “base side adhesive surface S3”) are arranged in the above-described arrangement direction. It arrange | positions so that it may oppose. The electrostatic chuck 100 further includes an adhesive layer 30 disposed between the ceramic side adhesive surface S2 of the ceramic plate 10 and the base side adhesive surface S3 of the base plate 20. The ceramic plate 10 corresponds to the insulating plate in the claims, and the ceramic side adhesive surface S2 of the ceramic plate 10 corresponds to the second surface in the claims.

  The ceramic plate 10 is, for example, a circular flat plate-like member, and is formed of ceramics (for example, alumina, aluminum nitride, etc.). The diameter of the ceramic plate 10 is, for example, about 200 mm to 500 mm (usually about 200 mm to 350 mm), and the thickness of the ceramic plate 10 is, for example, about 1 mm to 10 mm.

  A pair of internal electrodes 40 formed of a conductive material (for example, tungsten or molybdenum) is provided inside the ceramic plate 10. When a voltage is applied to the pair of internal electrodes 40 from a power source (not shown), an electrostatic attractive force is generated, and the wafer W causes the upper surface of the ceramic plate 10 (hereinafter referred to as an “attracting surface S1”) by the electrostatic attractive force. It is fixed by adsorption. The adsorption surface S1 of the ceramic plate 10 corresponds to the first surface in the claims.

  In addition, a heater 50 made of a resistance heating element formed of a conductive material (for example, tungsten or molybdenum) is provided inside the ceramic plate 10. When a voltage is applied to the heater 50 from the first power supply V1 and the second power supply V2 (see FIG. 4), the ceramic plate 10 is warmed by the heat generated by the heater 50 and is held on the suction surface S1 of the ceramic plate 10. The wafer W is heated. Thereby, the temperature control of the wafer W is realized. As shown in FIG. 3, the heater 50 is arranged substantially concentrically in the Z-axis direction view in order to warm the adsorption surface S <b> 1 of the ceramic plate 10 as uniformly as possible. A detailed configuration of the heater 50 will be described later.

  The base plate 20 is a circular flat plate-like member having the same diameter as the ceramic plate 10 or a larger diameter than the ceramic plate 10 and is formed of metal (for example, aluminum or aluminum alloy). The diameter of the base plate 20 is, for example, about 220 mm to 550 mm (usually 220 mm to 350 mm), and the thickness of the base plate 20 is, for example, about 20 mm to 40 mm.

  A coolant channel 21 is formed inside the base plate 20. When a coolant (for example, a fluorine-based inert liquid or water) flows through the coolant channel 21, the base plate 20 is cooled, and the ceramic plate is transferred by heat transfer from the base plate 20 to the ceramic plate 10 via the adhesive layer 30. 10 is cooled, and the wafer W held on the suction surface S1 of the ceramic plate 10 is cooled. Thereby, the temperature control of the wafer W is realized.

  The adhesive layer 30 includes, for example, an adhesive such as silicone resin, acrylic resin, or epoxy resin, and bonds the ceramic plate 10 and the base plate 20 together. The thickness of the adhesive layer 30 is, for example, about 0.1 mm to 1 mm.

A-2. Detailed configuration of the heater 50:
As shown in FIG. 3, the heater 50 includes a first heater wire 510, a second heater wire 520, and a third heater wire 530.

  The first heater line 510 is formed so as to straddle both the first region R1 and the second region R2 that are partitioned by a virtual line Q orthogonal to the first heater line 510 when viewed in the Z direction. ing. The first heater line 510 includes a first large heater line 511 and a first small heater line 512. Each of the first large heater wire 511 and the first small heater wire 512 has a substantially annular shape centering on a central axis O passing through the center position of the ceramic plate 10 parallel to the Z direction when viewed in the Z direction. Is formed.

  Specifically, the first large heater wire 511 has a pair of first end portions 511A and 511B arranged opposite to each other on an imaginary circle having the center axis O as the center, It is formed in a shape extending from one end portion 511A to the other first end portion 511B along the virtual circle. The first small heater wire 512 is centered on the central axis O, and a pair of first heaters arranged opposite to each other on a virtual circle having a smaller diameter than the virtual circle on which the first large heater wire 511 is formed. It has end portions 512A and 512B, and is formed in a shape extending from one first end portion 512A to the other first end portion 512B along the virtual circle.

  The second heater wire 520 is formed in the first region R1 as viewed in the Z direction, and is not formed in the second region R2. The second heater line 520 includes a second large heater line 521 and a second small heater line 522. Each of the second large heater line 521 and the second small heater line 522 is formed in a substantially semicircular shape centered on the central axis O as viewed in the Z direction.

  Specifically, the second large heater wire 521 is centered on the central axis O and has a smaller diameter than the imaginary circle on which the first large heater wire 511 is formed, and the first small heater wire 512 is formed. A pair of second end portions 521A and 521B arranged on the virtual line Q and having a diameter larger than that of the virtual circle, and one second end portion 521A. To the other second end 521B along the virtual circle. The second small heater wire 522 is on a virtual circle centered on the central axis O and having a diameter smaller than the virtual circle on which the first small heater wire 512 is formed, and on the virtual line Q. It has a pair of second end portions 522A and 522B arranged, and is formed in a shape extending from one second end portion 522A to the other second end portion 522B along the virtual circle. Yes.

  The third heater wire 530 is not formed in the first region R1, but is formed in the second region R2, as viewed in the Z direction. The third heater line 530 includes a third large heater line 531 and a third small heater line 532. Each of the third large heater wire 531 and the third small heater wire 532 is formed in a substantially semicircular shape centering on the central axis O as viewed in the Z direction.

  Specifically, the third large heater wire 531 is a pair of second heaters arranged on the virtual circle on which the second large heater wire 521 is formed and on the virtual line Q. It has three end portions 531A and 531B, and is formed in a shape extending from one third end portion 531A to the other third end portion 531B along the virtual circle. That is, one second end 521A of the second large heater wire 521 and one third end 531A of the third large heater wire 531 are arranged at the same place on the ceramic plate 10 and are electrically connected. The other second end 521B of the second large heater wire 521 and the other third end 531B of the third large heater wire 531 are at the same location on the ceramic plate 10 Arranged and electrically connected. The third small heater line 532 is a pair of third end portions 532A arranged on the virtual circle Q on which the second small heater line 522 is formed and on the virtual line Q. , 532B and extending from one third end 532A to the other third end 532B along the virtual circle. That is, one second end portion 522A of the second small heater wire 522 and one third end portion 532A of the third small heater wire 532 are disposed at the same location on the ceramic plate 10 and are electrically connected. Connected. Further, the other second end portion 522B of the second small heater wire 522 and the other third end portion 532B of the third small heater wire 532 are arranged at the same place on the ceramic plate 10 and are electrically connected. Connected.

  FIG. 4 is a schematic diagram showing a wiring relationship between the first large heater wire 511, the second large heater wire 521, and the third large heater wire 531. In FIG. 4, the left-right direction (X-axis direction) of the drawing is the direction around the central axis O (hereinafter referred to as “circumferential direction L”), and the first large heater line 511, the second large heater line 521, and the third The large heater wire 531 is shown as a linear shape extending in the left-right direction on the paper surface. As shown in FIG. 4, the first end 511A and the first end 511B of the first large heater wire 511 are connected to a pair of first power input terminals T1A and T1B ( The pair of first power supply input terminals T1A and T1B are electrically connected to a first power supply V1 disposed outside the electrostatic chuck 100. Connected. The circumferential direction L corresponds to the second direction in the claims.

  The second end 521A of the second large heater wire 521 and the third end 531A of the third large heater wire 531 are one second of the pair of second power input terminals T2A and T2B. The second end 521B of the second large heater line 521 and the third end 531B of the third large heater line 531 are electrically connected to the power input terminal T2A, and the other second power supply It is electrically connected to the input terminal T2B. The pair of second power supply input terminals T <b> 2 </ b> A and T <b> 2 </ b> B are electrically connected to a second power supply V <b> 2 disposed outside the electrostatic chuck 100. That is, the first large heater line 511 is electrically connected in series to the first power supply V1, and the second large heater line 521 and the third large heater line 531 are connected to the second large heater line 521. The power supply V2 is electrically connected in parallel. Similarly, the first small heater line 512 is connected in series to the first power source V1, and the second small heater line 522 and the third small heater line 532 are connected to the second small heater line 532. The power supply V2 is connected in parallel.

A-3. Effects of the embodiment:
For example, the first region R1 receives a pressure greater than the second region R2 due to variations in the formation pressure when forming the heater 50 in the manufacturing process of the electrostatic chuck 100 of the present embodiment, and as a result, the first region R1 It is assumed that the cross-sectional area perpendicular to the extending direction of the heater wire located in the region R1 (hereinafter referred to as “cross-sectional area”) is smaller than the cross-sectional area of the heater wire located in the second region R2. Here, in the example of FIG. 4, instead of the second large heater line 521 and the third large heater line 531, the first region R <b> 1 and the second region are similar to the first large heater line 511. In the comparative example in which one fourth heater wire (not shown) arranged so as to straddle both of R2 and electrically connected in series to the first power supply V1 is arranged, become that way. Since both the first large heater line 511 and the fourth heater line have a large resistance due to the relatively small cross-sectional area of the line portion located in the first region R1, the first large heater wire 511 and the fourth heater wire The calorific value of the line part located is larger than the calorific value of the line part located in the second region R2. As a result, the temperature of the surface portion corresponding to the first region R1 in the adsorption surface S1 of the ceramic plate 10 becomes higher than the temperature of the surface portion corresponding to the second region R2, and the adsorption surface S1 of the ceramic plate 10 The temperature distribution tends to be non-uniform.

  On the other hand, in the electrostatic chuck 100 of the present embodiment, as described above, the first heater wire 510 has a heat generation amount of the line portion located in the first region R1 in the second region R2. It becomes larger than the calorific value of the line part. On the other hand, the second heater wire 520 is disposed in the first region R1, is not disposed in the second region R2, and the third heater wire 530 is not disposed in the first region R1. Instead, the second heater wire 520 and the third heater wire 530 are electrically connected in parallel. For this reason, since the resistance of the second heater wire 520 located in the first region R1 is larger than the resistance of the third heater wire 530 located in the second region R2, the amount of heat generated by the second heater wire 520. Becomes smaller than the amount of heat generated by the third heater wire 530. That is, in the first region R1, the heat value of the line portion located in the first region R1 of the first heater wire 510 is larger than the heat value of the line portion located in the second region R2, The heat value of the second heater wire 520 is smaller than the heat value of the third heater wire 530. On the other hand, in the second region R2, the heat value of the line portion located in the second region R2 of the first heater wire 510 is smaller than the heat value of the line portion located in the first region R1, The amount of heat generated by the third heater wire 530 is greater than the amount of heat generated by the second heater wire 520. Therefore, compared to the comparative example, it is possible to suppress a decrease in the uniformity of the temperature distribution of the adsorption surface S1 of the ceramic plate 10.

  In the present embodiment, as described above, the second heater wire 520 is disposed in the first region R1 and is not disposed in the second region R2, and the third heater wire 530 is It is not disposed in the first region R1, but is disposed in the second region R2. For this reason, the second heater wire 520 partially extends to the second region R2 or the third heater wire 530 partially extends to the first region R1 as compared to the second region R2. When the heater wire 520 and the third heater wire 530 are arranged close to each other, it is possible to prevent the specific portion of the ceramic plate 10 from becoming high temperature.

  Furthermore, in the present embodiment, the first heater wire 510 forms an annular shape extending along the direction L around the central axis O, and the combination of the second heater wire 520 and the third heater wire 530 is: The first heater wire 510 has an annular shape having a different diameter. Thereby, compared with the case where the heater wire of the heater 50 is not annular shape, the uniformity of the temperature distribution of the adsorption surface S1 of the ceramic plate 10 can be improved.

  Moreover, the 1st heater wire 510, the 2nd heater wire 520, and the 3rd heater wire 530 are alternately arrange | positioned in the radial direction of the ceramic board 10 (refer FIG. 3). Thereby, the uniformity of temperature distribution can be improved over the wide range of adsorption surface S1 of the ceramic board 10. FIG.

B. Second embodiment:
FIG. 5 is an explanatory diagram showing an XY cross-sectional configuration of the electrostatic chuck 100a according to the second embodiment. Hereinafter, among the configurations of the electrostatic chuck 100a in the second embodiment, the same configurations as the configurations of the electrostatic chuck 100 in the first embodiment described above are denoted by the same reference numerals, and the description thereof is omitted as appropriate. .

  The heater 50a of this embodiment includes a second heater wire 620 and a third heater wire 630 instead of the second heater wire 520 and the third heater wire 530 of the first embodiment. The second heater wire 620 is disposed at substantially the same position as the second heater wire 520 of the first embodiment. The second heater line 620 includes a second large heater line 621 and a second small heater line 622. The second large heater wire 621 has a pair of second ends 621A and 621B disposed on the same side as the first end 511A with respect to the central axis O, and one second end. While extending from the portion 621A to one side in the circumferential direction L (clockwise direction in FIG. 5), it is folded back to the other side (counterclockwise direction in FIG. 5) and connected to the other second end portion 621B. . Specifically, the second large heater wire 621 is formed in an arc shape centering on the central axis O from each of the pair of second end portions 621A and 621B and the pair of second end portions 621A and 621B. A pair of arc portions extending to the vicinity of the imaginary line Q and a connecting portion connecting the tip ends of the pair of arc portions are included.

  The second small heater wire 622 has a pair of second end portions 622A and 622B disposed on the same side as the first end portion 511A with respect to the central axis O, and one second end. It extends from the portion 622A to one side in the circumferential direction L (clockwise direction in FIG. 5) and is folded back to the other side (counterclockwise direction in FIG. 5) to connect to the other second end portion 622B. . Specifically, the second small heater wire 622 is formed in an arc shape from the pair of second ends 622A and 622B and the pair of second ends 622A and 622B with the central axis O as the center. A pair of arc portions extending to the vicinity of the imaginary line Q and a connecting portion connecting the tip ends of the pair of arc portions are included.

  The third heater wire 630 is disposed at substantially the same position as the third heater wire 530 of the first embodiment. The third heater line 630 includes a third large heater line 631 and a third small heater line 632. The third large heater wire 631 has a pair of third ends 631A and 631B arranged on the same side (Y-axis negative direction side) as the first end 511A and the like with respect to the central axis O. , Extending from one third end portion 631A to the other side in the circumferential direction L (counterclockwise direction in FIG. 5) and turning back to one side (clockwise direction in FIG. 5) to the other third end portion 631B It forms a connected shape. Specifically, the third large heater wire 631 is formed in an arc shape from the pair of third end portions 631A and 631B and the pair of third end portions 631A and 631B around the central axis O. A pair of arc portions extending to the vicinity of the imaginary line Q and a connecting portion connecting the tip ends of the pair of arc portions are included.

  The third small heater wire 632 has a pair of third ends 632A and 632B disposed on the same side as the first end 511A and the like with respect to the central axis O, and has one third end. While extending from the portion 632A to the other side in the circumferential direction L (counterclockwise direction in FIG. 5), it is folded back to one side (clockwise direction in FIG. 5) and connected to the other third end portion 632B. . Specifically, the third small heater wire 632 has a pair of third end portions 632A and 632B and a pair of third end portions 632A and 632B in an arc shape around the central axis O. A pair of arc portions extending to the vicinity of the imaginary line Q and a connecting portion connecting the tip ends of the pair of arc portions are included.

  According to this embodiment, since each of the second heater wire 620 and the third heater wire 630 is formed in a folded shape, the first end portions 512A and 512B and the second end portions 621A and 621B. And the third end portions 631A and 631B can be arranged close to each other, so that the wiring structure of the entire heater 50a can be simplified.

C. Third embodiment:
FIG. 6 is an explanatory diagram illustrating an XY cross-sectional configuration of the electrostatic chuck 100b according to the third embodiment. Hereinafter, among the configurations of the electrostatic chuck 100b in the third embodiment, the same configurations as the configurations of the electrostatic chuck 100a in the second embodiment described above are denoted by the same reference numerals, and the description thereof is omitted as appropriate. .

  The heater 50b of the present embodiment includes a first heater wire 710 instead of the first heater wire 510 in the second embodiment. The first heater wire 710 extends from one first end portion 710A so as to surround both the inner peripheral side and the outer peripheral side of the second heater wire 620 and the third heater wire 630, and the other first The shape connected with the edge part 710B of this is comprised. Specifically, the first heater wire 710 passes between the second small heater wire 622 and the third small heater wire 632 from the first end 710A located in the vicinity of the central axis O. And a circular portion extending in a circular shape so as to surround the outer periphery of the second small heater wire 622 and the third small heater wire 632 from the tip of the straight portion. Furthermore, the first heater wire 710 includes a linear portion extending so as to pass between the second large heater wire 621 and the third large heater wire 631 from the tip of the circular portion, and from the tip of the straight portion. A circular portion extending in a circular shape so as to surround the outer periphery of the second large heater wire 621 and the third large heater wire 631 and connected to the first end portion 710B.

  According to the present embodiment, the first heater wire 710 has one first end portion 710 </ b> A that surrounds both the inner and outer peripheral sides of the second and third heater wires 620 and 630. The shape which extends from this and is connected with the other 1st edge part 710B is comprised. For this reason, the number of ends of the first heater wire 710 is two. Thereby, compared with the said 1st Embodiment and 2nd Embodiment, the wiring structure of the heater 50b whole can be simplified by the part in which the number of the edge parts of the 1st heater wire 710 is small.

D. Variations:
The technology disclosed in the present specification is not limited to the above-described embodiment, and can be modified into various forms without departing from the gist thereof. For example, the following modifications are possible.

  In the above-described embodiment, the second heater wire 520 and the third heater wire 530 are electrically connected on the same layer of the ceramic plate 10 (see FIG. 3 and the like), but are not limited thereto. First, the second heater wire 520 and the third heater wire 530 are arranged at positions physically separated on the layer where the second heater wire 520 and the third heater wire 530 are formed. The ends of the line 530 may be electrically connected to another layer through vias (not shown) or the like.

  In the above embodiment, the first heater wire 510, the second heater wire 520, and the third heater wire 530 are arranged on the same layer of the ceramic plate 10. However, the present invention is not limited to this. At least one of the first heater line 510, the second heater line 520, and the third heater line 530, or at least a part of the heater line may be disposed in another layer.

  In the above embodiment, the first power supply V1 and the second power supply V2 may be a common power supply. Further, both ends of the first heater wire 510 may be electrically connected to both ends of the second heater wire 520 and the third heater wire 530, respectively. Specifically, in the example of FIG. 4, the first end 511A of the first large heater wire 511 and the second end 521A of the second large heater wire 521 (of the third large heater wire 531). The third end portion 531A) is electrically connected, and the first end portion 511B of the first large heater wire 511 and the second end portion 521B (third large portion of the second large heater wire 521). The third end portion 531B) of the heater wire 531 may be electrically connected.

  In each of the above embodiments, a part of the second heater wire 520 may extend to the second region R2, or a part of the third heater wire 530 may extend to the first region R1. In short, as viewed in the Z direction, at least a portion of the second heater line 520 corresponds to the third heater line 530 with respect to one line portion of the first heater line 510 (the portion located in the first region R1). The third heater wire 530 is arranged closer to another line portion (the portion located in the second region R2) of the first heater wire 510, and at least a part of the third heater wire 530 is the second heater wire. If it is arranged closer to 520, it is possible to prevent the uniformity of the temperature distribution on the adsorption surface S1 of the ceramic plate 10 from being reduced due to the variation in the cross-sectional area of the heater wire.

  In addition to the entire ceramic plate 10, at least a part of the second heater wire 520 is located closer to the third heater wire 530 than a portion of the first heater wire 510 with respect to a part of the ceramic plate 10. If the arrangement condition that at least a part of the third heater line 530 is arranged closer to the second heater line 520 than another line portion of the first heater line 510 is satisfied. Good. Thereby, about the said part, it can suppress that the uniformity of the temperature distribution of adsorption | suction surface S1 of the ceramic board 10 resulting from the variation in the cross-sectional area of a heater wire falls.

  In each said embodiment, the shape of heater 50, 50a, 50b is not limited to cyclic | annular shape or circular arc shape, A linear shape, a helical shape, etc. may be sufficient.

  Moreover, the material which forms each member in the said embodiment is an illustration to the last, and each member may be formed with another material. Moreover, in the said embodiment, although the heater 50 is arrange | positioned inside the ceramic board 10, the heater 50 is not the inside of the ceramic board 10, but the base board 20 side (ceramic board 10 and adhesive layer of the ceramic board 10). 30). In this case, the adhesive layer 30 adheres at least one of the ceramic plate 10 and the heater 50 to the base plate 20.

  In the above embodiment, the refrigerant flow path 21 is formed inside the base plate 20, but the refrigerant flow path 21 is not inside the base plate 20 but on the surface of the base plate 20 (for example, the base plate 20 and It may be formed between the adhesive layer 30). Moreover, in the said embodiment, although the bipolar system with which a pair of internal electrode 40 was provided in the inside of the ceramic board 10 was employ | adopted, the monopolar system in which the one internal electrode 40 was provided in the inside of the ceramic board 10 is used. It may be adopted.

  The present invention is not limited to the electrostatic chuck 100 that holds the wafer W using electrostatic attraction, but includes other ceramic holding plates (for example, a ceramic plate and a base plate) that hold an object on the surface of the ceramic plate (for example, It can also be applied to a holding device (heater with shaft) that does not have a base plate or an adhesive layer and holds an object on the surface of a ceramic plate. Furthermore, the holding device includes, for example, a polyimide heater configured by sandwiching a heater wire of metal foil (copper foil or stainless steel foil) between polyimide resin layers. For example, the heater wire may have a non-uniform cross-sectional area due to variations in the etching width when the heater wire is formed by etching the metal foil. The present invention can also be applied to such a polyimide heater. In this case, the polyimide heater itself corresponds to the insulating plate in the claims. In the present specification, “holding the object on the first surface side of the insulating plate” is not limited to holding the object directly on the first surface of the insulating plate. The object may be held on the surface side of 1 via another member. For example, the object may be held on the surface opposite to the polyimide heater of the ceramic plate separately disposed on the first surface of the polyimide heater.

  10: Ceramic plate 20: Base plate 21: Refrigerant flow path 30: Adhesive layer 40: Internal electrode 50, 50a, 50b: Heater 100, 100a, 100b: Electrostatic chuck 510, 710: First heater wire 511: First Large heater wire 511A, 511B, 512A, 512B, 710A, 710B: first end 512: first small heater wire 520, 620: second heater wire 521, 621: second large heater wire 521A, 521B, 621A, 621B, 522A, 522B, 622A, 622B: second end 522, 622: second small heater wire 530, 630: third heater wire 531, 631: third large heater wire 531A, 531B, 532A, 532B, 631A, 631B, 632A, 632B: Third end portion 532, 632: 3 small heater wires L: circumferential direction O: central axis Q: virtual line R1: first region R2: second region S1: adsorption surface S2: ceramic side adhesive surface S3: base side adhesive surface T1A, T1B, T2A , T2B: power input terminal V1: first power supply V2: second power supply W: wafer

Claims (6)

A plate-like insulating plate having a first surface and a second surface opposite to the first surface;
A heater disposed inside the insulating plate or on the second surface side of the insulating plate;
A holding device for holding an object on the first surface side of the insulating plate,
The heater is
A first heater wire having a pair of first ends and extending from one of the pair of first ends to the other;
A second heater wire having a pair of second ends and extending from one of the pair of second ends to the other;
A pair of third ends, extending from one of the pair of third ends to the other, and one of the pair of third ends being a portion of the pair of second ends A third heater wire electrically connected to one side, and the other of the pair of third ends being electrically connected to the other of the pair of second ends,
In a first direction perpendicular to the first surface of the insulating plate,
At least a part of the second heater line is disposed closer to the third heater line than one line portion of the first heater line;
At least a part of the third heater line is different from the first line in the second direction in which the first heater line extends in a second direction different from the first line. The holding device is disposed closer to the second heater wire. The holding device according to claim 1, wherein
As viewed in the first direction, the second heater wire is disposed in one of two regions of the insulating plate that are partitioned by a virtual line orthogonal to the first heater wire, No. 3 heater wire is not disposed, and the second heater wire is not disposed in the other region, and the third heater wire is disposed. The holding device according to claim 1 or 2,
The second direction is a direction around the center of the insulating plate;
In the first direction view,
The first heater wire constitutes an annular shape extending along the second direction,
The holding device, wherein the combination of the second heater wire and the third heater wire constitutes at least a part of an annular shape having a diameter different from that of the first heater wire. In the holding device according to any one of claims 1 to 3,
In the first direction view,
The second heater wire extends from one of the pair of second ends to one side in the second direction and is folded back to the other side to be connected to the other of the pair of second ends. And
The third heater wire has a shape that extends from one of the pair of third ends to the other side in the second direction and is folded back to one side to be connected to the other of the pair of third ends. A holding device. In the holding device according to any one of claims 1 to 4,
In the first direction view,
The first heater wire is one of the pair of first ends so as to surround both the inner and outer sides of the second heater wire and the third heater wire forming an annular shape. A holding device, characterized in that it has a shape extending from the other end of the pair of first ends. In the holding device according to any one of claims 1 to 5,
As viewed in the first direction, the first heater wire, the second heater wire, and the third heater wire form an annular shape of the second heater wire and the third heater wire. The holding device is alternately arranged in a direction from the inner periphery side to the outer periphery side.

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