Holding device

Abstract

To provide a holding device that can improve the insulating performance in the holding device.SOLUTION: An electrostatic chuck 1 includes a holding surface 11, a lower surface 12, a heater electrode 70, a driver electrode 80 connected to the heater electrode 70, a gas hole 16 and a temperature sensor hole 15, and an electrode pad 62, and holds a semiconductor wafer W on the holding surface 11. The driver electrode 80 includes a pair of a positive electrode side electrode 80a and a negative electrode side electrode 80b disposed adjacent to each other in a surface direction. In the surface direction, at least one of the gas hole 16 and the temperature sensor hole 15, and the electrode pad 62 is disposed between the positive electrode side electrode 80a and the negative electrode side electrode 80b. Each of the positive electrode side electrode 80a and the negative electrode side electrode 80b includes an arc concave part 81 that is depressed toward the electrode along the gas hole 16 and the temperature sensor hole 15, or the electrode pad 62 so as to avoid the gas hole 16 and the temperature sensor hole 15, or the electrode pad 62. Both ends 81e of the arc concave part 81 is formed to be rounded.SELECTED DRAWING: Figure 4

Description

Technical Field

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

Background Art

[0002] In the semiconductor manufacturing process, an electrostatic chuck (holding member) is used to hold a semiconductor wafer. As such an electrostatic chuck, for example, as described in Patent Document 1, there is one having a ceramic member (plate-like member) that holds an object on an adsorption surface (holding surface), and a driver electrode connected to a heater electrode inside the ceramic member. And such an electrode is formed by screen printing using a metallized paste (conductive ink).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the above-described electrostatic chuck, when forming the driver electrode, if the dropping of the conductive ink from the screen mask deteriorates, there is a risk that the conductive ink will become angular at that portion. For example, in a portion where the area of the opening in the screen mask is small (for example, a corner portion), the surface tension increases when the screen mask is peeled off, so that the dropping of the conductive ink deteriorates.

[0005] When the conductive ink forms a corner, the conductive ink at the corner portion may protrude into an unintended portion (a portion different from the designed shape), making it impossible to create the driver electrode in the shape according to the mask pattern. Also, if the conductive ink at the corner portion maintains its shape without protruding into an unintended portion, the ceramic green sheet bulges at that portion, creating a space inside the fired ceramic member. When such an event occurs, the insulation performance of the electrostatic chuck deteriorates. In recent years, the application of high voltages to electrostatic chucks (due to use at high power) has been increasing, and higher insulation performance is required for electrostatic chucks.

[0006] Therefore, the present disclosure has been made to solve the above-described problems, and an object thereof is to provide a holding device capable of improving the insulation performance in the holding device.

Means for Solving the Problems

[0007] One aspect of the present disclosure made to solve the above problems is a first surface, a second surface provided on the side opposite to the first surface in the thickness direction, a heater electrode disposed between the first surface and the second surface, a driver electrode connected to the heater electrode, a hole formed in the thickness direction and opening on the second surface, and an electrode pad electrically connected to an external power source, in a holding device for holding an object on the first surface, the driver electrode has a pair of positive electrode side electrodes and negative electrode side electrodes arranged adjacent to each other in the plane direction, in the plane direction, at least one of the hole or the electrode pad is disposed between the positive electrode side electrode and the negative electrode side electrode, each of the positive electrode side electrode and the negative electrode side electrode includes an arc-shaped recess recessed toward the electrode side along the hole or the electrode pad so as to avoid the hole or the electrode pad, characterized in that both ends of the arc-shaped recess are formed in an R shape.

[0008] In this holding device, as driver electrodes, it has a pair of positive electrode side electrodes and negative electrode side electrodes arranged adjacent to each other in the plane direction. In the plane direction, at least one of a hole or an electrode pad is arranged between the positive electrode side electrode and the negative electrode side electrode. And each of the positive electrode side electrode and the negative electrode side electrode is provided with an arc-shaped recess recessed toward the electrode side along the hole or the electrode pad so as to avoid the hole or the electrode pad, and both ends of the arc-shaped recess are formed in an R shape.

[0009] By making both ends (edge portions) of the arc-shaped recess of the driver electrode into an R shape in this way, the opening (area) in the screen mask corresponding to this portion becomes larger. Therefore, when manufacturing the driver electrode by screen printing, it is possible to make the conductive ink easily fall out from the screen mask at this portion. Therefore, the generation of the cornering of the conductive ink can be suppressed.

[0010] As a result, the overflow of the conductive ink to the hole or the electrode pad side can be suppressed, so that the driver electrode can be manufactured in the shape (designed shape) of the mask pattern. Therefore, it is possible to prevent the distance (insulation distance) between the driver electrode and the hole or the electrode pad formed in the holding device from becoming smaller than the designed value, and thus the insulation performance in the holding device can be improved.

[0011] Also, in this holding device, since each of the positive electrode side electrode and the negative electrode side electrode of the driver electrode is provided with an arc-shaped recess recessed toward the electrode side along the hole so as to avoid the hole, it is possible to prevent the driver electrode from being exposed inside the hole. This also contributes to the improvement of the insulation performance in the holding device.

[0012] In recent years, in order to control the temperature of the holding surface with high precision due to the increasing speed of process processing, there has been an increase in the number of cases where multiple heater electrodes are provided (multiple independently controllable heating zones are provided), and in such cases, the driver electrode is also divided into multiple parts and arranged. This reduces the area per driver electrode, which results in a decrease in the allowable current amount and an increase in the resistance value of the driver electrode, so it is desirable to increase the area of the driver electrode to minimize these issues.

[0013] Therefore, in this holding device, at least one of a hole and an electrode pad is disposed between the positive electrode and the negative electrode, which prevents a reduction in the area of the driver electrode, and therefore prevents a decrease in the allowable current and an increase in the resistance value of each driver electrode, even when multiple heater electrodes are provided.

[0014] In the above-mentioned holding device, Each of the positive electrode and the negative electrode has a semicircular or fan-like shape when viewed in the thickness direction, and includes at least one of an arc and a central angle, It is preferable that both ends of the arc and the apex of the central angle are formed in an R-shape.

[0015] In this way, by making the corners of the driver electrode, including both ends of the arc-shaped recess and the apex of the central angle of the driver electrode, rounded, the driver electrode can be manufactured to the shape of the mask pattern (design shape) with high precision, thereby further improving the insulating performance of the holding device.

[0016] Here, since a high potential is applied to the chuck electrode in the holding device, a large potential difference occurs between the electrode pad connected to the chuck electrode and the driver electrode, and therefore, dielectric breakdown is most likely to occur in this area.

[0017] Therefore, in any of the above-mentioned holding devices, a chuck electrode that generates an electrostatic attraction force; Preferably, the electrode pad is electrically connected to the chuck electrode.

[0018] By doing so, even between the electrode pad connected to the chuck electrode and the driver electrode, where the potential difference from the driver electrode is the largest, the required insulation distance can be ensured. Therefore, it is possible to reliably prevent the occurrence of dielectric breakdown between the electrode pad connected to the chuck electrode and the driver electrode, and the insulation performance of the holding device can be improved.

Advantages of the Invention

[0019] According to the present disclosure, it is possible to provide a holding device capable of improving the insulation performance in the holding device.

Brief Description of the Drawings

[0020] [Figure 1] It is a schematic perspective view of an electrostatic chuck according to an embodiment. [Figure 2] It is a schematic configuration diagram of an XZ cross-section of an electrostatic chuck according to an embodiment. [Figure 3] It is a diagram showing the shape of a driver electrode. [Figure 4] It is a diagram showing an enlarged view of part A shown in FIG. 3. [Figure 5] It is a diagram showing an enlarged view of part B shown in FIG. 3. [Figure 6] It is a diagram showing an enlarged view of part C shown in FIG. 3. [Figure 7] It is a diagram showing a modified example of a driver electrode.

Embodiments for Carrying Out the Invention

[0021] A holding device according to an embodiment of the present disclosure will be described in detail with reference to the drawings. In this embodiment, as the holding device, for example, an electrostatic chuck used in a semiconductor manufacturing device such as a film forming device (CVD film forming device, sputtering film forming device, etc.) or an etching device (plasma etching device, etc.) will be exemplified and described.

[0022] Therefore, the electrostatic chuck 1 of the present embodiment will be described with reference to FIGS. 1 to 5. The electrostatic chuck 1 of the present embodiment is a device that adsorbs 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 apparatus. As shown in FIG. 1, the electrostatic chuck 1 includes a plate-like member 10, a base member 20, and a bonding layer 30 that bonds the plate-like member 10 and the base member 20.

[0023] In the following description, for convenience of explanation, the XYZ axes are defined as shown in FIG. 1. Here, the Z axis is the axis in the axial direction (the vertical direction in FIG. 1) of the electrostatic chuck 1, and is an example of the "thickness direction" of the present disclosure. Further, the X axis and the Y axis are the axes in the radial direction of the electrostatic chuck 1, and the direction of the XY plane is an example of the "plane direction" of the present disclosure.

[0024] As shown in FIG. 1, the plate-like member 10 is a disc-shaped member formed of ceramics. Specifically, the plate-like member 10 has a stepped disc shape in which two discs with different diameters overlap with a common central axis (specifically, a disc-shaped upper stage portion 10a having a small diameter overlaps on a disc-shaped lower stage portion 10b having a large diameter). In this way, the lower stage portion 10b is provided on the side opposite to the holding surface 11 side with respect to the upper stage portion 10a in the thickness direction (the direction coinciding with the Z-axis direction, the vertical direction) of the plate-like member 10, and has an outer circumference larger than that of the upper stage portion 10a when viewed from the thickness direction of the plate-like member 10.

[0025] Note that various ceramics are used as the ceramics, but from the viewpoints of strength, wear resistance, plasma resistance, etc., for example, ceramics mainly composed of aluminum oxide (alumina, Al2O3) or aluminum nitride (AlN) are preferably used. Here, the main component means the component having the largest content ratio (for example, a component having a volume content ratio of 90 vol% or more).

[0026] 1 and 2, the plate-shaped member 10 has a holding surface 11 (upper surface) that holds the semiconductor wafer W, and a lower surface 12 that is provided on the opposite side of the holding surface 11 in the thickness direction (i.e., the Z-axis direction) of the plate-shaped member 10. In this embodiment, the upper stage portion 10a has the holding surface 11, and the semiconductor wafer W is held on the holding surface 11. The holding surface 11 is an example of a "first surface" in the present disclosure, and the lower surface 12 is an example of a "second surface" in the present disclosure.

[0027] Here, the diameter of the lower portion 10b of the plate-shaped member 10 is larger than that of the upper portion 10a, and the upper portion 10a has a diameter of, for example, about 150 mm to 300 mm, while the lower portion 10b has a diameter of, for example, about 180 mm to 400 mm. The thickness of the plate-shaped member 10 is, for example, about 2 mm to 6 mm. The thermal conductivity of the plate-shaped member 10 is preferably within a range of 10 W / mK to 50 W / mK (more preferably, 18 W / mK to 30 W / mK).

[0028] As shown in FIG. 2, the plate-like member 10 includes a chuck electrode 50 therein. 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 (e.g., tungsten, molybdenum, etc.). A power supply terminal 63, which is connected to an external power supply (not shown), is electrically connected to the chuck electrode 50 through a plurality of electrically connected vias 61 and electrode pads 62. The vias 61 and the electrode pads 62 are made of a conductive material (e.g., tungsten, molybdenum, etc.). When a voltage is applied to the chuck electrode 50 from the external power supply through the power supply terminal 63, the plurality of vias 61, and the electrode pads 62, an electrostatic attraction force (attraction force) is generated, and the semiconductor wafer W is attracted and fixed to the holding surface 11 by this electrostatic attraction force.

[0029] The plate-like member 10 also includes a heater electrode 70 and a driver electrode 80. These electrodes are made of a conductive material (for example, tungsten or molybdenum). The heater electrode 70 is a heating resistor that heats the holding surface 11 to a predetermined temperature, and is patterned, for example, in a spiral shape when viewed in the Z-axis direction. The driver electrode 80 is electrically connected to this heater electrode 70.

[0030] The driver electrode 80 is an electrode for supplying power to the heater electrode 70, and as shown in FIG. 3, has a pair of a positive electrode 80a and a negative electrode 80b patterned to have predetermined regions parallel to the surface (XY plane). In this embodiment, two driver electrodes 80 are provided, and the positive electrode 80a and the negative electrode 80b each have a sector shape. The driver electrode 80 is disposed closer to the lower surface 12 (lower side) than the heater electrode 70 and is connected to the heater electrode 70 through a via 82 (see FIG. 2). The driver electrode 80 is connected to an external power supply through vias, electrode pads, and power supply terminals (not shown), and power is supplied from the external power supply to the heater electrode 70 via the driver electrode 80. Details of the driver electrode 80 will be described later.

[0031] 2, the plate-shaped member 10 has a plurality of holes (bottomed holes and through-holes) that open to the lower surface 12 and are formed in the Z-axis direction. Specifically, the plate-shaped member 10 has bottomed terminal holes 14 and temperature sensor holes 15, as well as gas holes 16 and lift pin holes 17 that are through-holes that penetrate the holding surface 11 and the lower surface 12. The terminal holes 14, temperature sensor holes 15, gas holes 16, and lift pin holes 17 are examples of "holes" in the present disclosure.

[0032] The terminal hole 14 is a bottomed hole in which a power supply terminal 63 electrically connected to the chuck electrode 50 is disposed. The terminal hole 14 is a circular recess that opens to the lower surface 12, and an area of the terminal hole 14 that overlaps with a through hole 24 of the base member 20 (described later) is recessed toward the holding surface 11 as viewed in the Z-axis direction.

[0033] The temperature sensor hole 15 is a bottomed hole in which a temperature sensor (thermistor) for detecting the temperature of the holding surface 11 is disposed. Note that the temperature sensor is disposed on the bottom surface of the temperature sensor hole 15 (the portion closest to the holding surface). This temperature sensor hole 15 is a circular bottomed hole that opens to the lower surface 12 and extends to the vicinity of the holding surface 11 (near the center of the thickness of the upper stage portion 10a).

[0034] The gas hole 16 is a hole for supplying an inert gas (e.g., He gas, etc.) to the minute space between the holding surface 11 and the semiconductor wafer W held on the holding surface 11. The lift pin hole 17 is a hole for disposing a lift pin for lifting the semiconductor wafer W held on the holding surface 11.

[0035] As shown in FIG. 1, the base member 20 is disposed on the side opposite to the holding surface 11 side with respect to the plate-like member 10. This base member 20 is formed, for example, in a columnar shape. Further, the base member 20 is formed of, for example, a metal (e.g., aluminum, aluminum alloy, etc.), but may be other than a metal.

[0036] As shown in FIGS. 1 and 2, the base member 20 includes an upper surface 21 and a lower surface 22 provided on the side opposite to the upper surface 21 in the thickness direction of the base member 20 (i.e., the Z-axis direction). The upper surface 21 of the base member 20 is thermally connected to the lower surface 12 of the plate-like member 10 via the bonding layer 30.

[0037] The diameter of the base member 20 is, for example, about 180 mm to 400 mm. Further, the thickness (dimension in the Z-axis direction) of the base member 20 is, for example, about 20 mm to 50 mm. Note that the thermal conductivity of the base member 20 (assuming aluminum) is desirably in the range of 160 mm to 250 W / mK (preferably about 230 W / mK).

[0038] Such base member 20 has through holes 24, 25, 26, and 27 formed therein, penetrating in the thickness direction (Z-axis direction, up-down direction in FIG. 2 ) between upper surface 21 and lower surface 22. Through hole 24 communicates with terminal hole 14, through hole 25 communicates with temperature sensor hole 15, through hole 26 communicates with gas hole 16, and through hole 27 communicates with lift pin hole 17.

[0039] The base member 20 is formed with a coolant flow path (not shown) for flowing a coolant (e.g., a fluorine-based inert liquid, water, etc.). By flowing the coolant through this coolant flow path, the base member 20 is cooled, and the plate-like member 10 is cooled via the bonding layer 30. This allows the semiconductor wafer W held on the holding surface 11 to be cooled.

[0040] As shown in FIGS. 1 and 2, the bonding layer 30 is disposed between the lower surface 12 of the plate-shaped member 10 and the upper surface 21 of the base member 20, and bonds the plate-shaped member 10 and the base member 20 together in a heat-transferable manner. The bonding layer 30 is made of a resin adhesive, such as a silicone-based resin, an acrylic-based resin, or an epoxy-based resin. The thickness (dimension in the Z-axis direction) of the bonding layer 30 is, for example, approximately 0.1 mm to 1.5 mm. The thermal conductivity of the bonding layer 30 is, for example, 1.0 W / mK. The thermal conductivity of the bonding layer 30 (assumed to be a silicone-based resin) is preferably within a range of 0.1 W / mK to 2.0 W / mK (preferably, 0.5 W / mK to 1.5 W / mK). The bonding layer 30 has through holes formed therein for connecting the through hole 24 and the terminal hole 14, the through hole 25 and the temperature sensor hole 15, the through hole 26 and the gas hole 16, and the through hole 27 and the lift pin hole 17.

[0041] The shape of the driver electrode 80 will now be described with reference to FIGS. 3 to 6. As shown in FIG. 3, the driver electrode 80 includes a pair of positive and negative electrodes 80a and 80b that are sector-shaped when viewed in the Z-axis direction. In this embodiment, two driver electrodes 80 are provided, with two sector-shaped positive electrodes 80a and two sector-shaped negative electrodes 80b arranged. The pair of positive and negative electrodes 80a and 80b are arranged adjacent to each other in the planar (XY plane) direction and have approximately the same shape (area). Therefore, the amount of heat generated by each electrode 80a and 80b is approximately the same, so that heat generated by the driver electrode 80 does not adversely affect the temperature distribution on the holding surface 11.

[0042] In the planar direction, gas holes 16, temperature sensor holes 15, and electrode pads 62 are arranged between the electrodes (between the electrodes 80a and 80b, as well as between the electrodes 80a and 80a, between the electrodes 80b and 80b, or between the driver electrodes 80 and 80b). For example, as shown in FIG. 3, the gas holes 16 (temperature sensor holes 15) are arranged between the positive electrode 80a and the negative electrode 80b. Furthermore, the electrode pads 62 are arranged between the driver electrodes 80 and 80b. In the present disclosure, "arranged between the electrodes" does not necessarily mean that the holes 15 and 16 or the electrode pads 62 are arranged entirely between the electrodes (for example, the gas holes in FIG. 3 are arranged at the chord portions of the sector-shaped electrodes 80a and 80b), but also includes the case where only a portion of them is arranged (for example, the electrode pads 62 in FIG. 3 are arranged at the center of the plate-shaped member 10, in other words, near the apex 85t of the central angle 85 of the sector-shaped electrodes 80a and 80b).

[0043] Although some illustrations are omitted, in order to prevent the gas holes 16, temperature sensor holes 15, electrode pads 62, and driver electrodes 80 from overlapping in the Z-axis direction view, each of the positive electrode side electrode 80a and the negative electrode side electrode 80b is formed with an arc-shaped recess 81 that is recessed (notched) along these and avoiding the gas holes 16, temperature sensor holes 15, and electrode pads 62 as shown in FIGS. 3 and 4. And as shown in FIG. 4, both ends 81e, 81e of this arc-shaped recess 81 are formed in an R shape (a shape obtained by performing R chamfering to eliminate corners). Note that the diameter of the R-shaped portion is preferably about 0.2 mm to 2.0 mm, for example.

[0044] Also, as shown in FIG. 3, the positive electrode side electrode 80a and the negative electrode side electrode 80b each have an arc 84 and a central angle 85 (located near the center of the plate-like member 10). As shown in FIGS. 5 and 6 (parts B and C of FIG. 3), both ends 84e, 84e of the arc 84 and the top 85t of the central angle 85 are formed in an R shape. Specifically, as shown in FIG. 5 (part B of FIG. 3), both ends 84e, 84e of the arc 84 are in an R shape that protrudes outward from the electrode, and as shown in FIG. 6 (part C of FIG. 3), the top 85t of the central angle 85 is in an R shape that is recessed inward from the electrode. That is, the top 85t in the R shape that is recessed inward from the electrode also forms the arc-shaped recess 81.

[0045] Here, the driver electrode 80 is formed by screen printing using a conductive ink (metallizing paste). Therefore, when forming the driver electrode, in a portion where the area of the opening in the screen mask is small (such as a corner), the surface tension increases when the screen mask is peeled off, so the conductive ink is likely to remain and the conductive ink may form corners. And if such corner formation of the conductive ink occurs, it may become impossible to create the driver electrode in the shape according to the mask pattern, or a space may be formed inside the plate-like member after firing, resulting in a decrease in the insulation performance of the electrostatic chuck.

[0046] Therefore, in the electrostatic chuck 1 of this embodiment, a pair of positive and negative electrodes 80a and 80b constituting the driver electrode 80 is provided, and the gas holes 16, the temperature sensor holes 15, or the electrode pads 62 are arranged between the positive and negative electrodes 80a and 80b in the planar (XY) direction. Then, each of the positive and negative electrodes 80a and 80b is provided with an arc-shaped recess 81 recessed toward the electrode along the gas holes 16, the temperature sensor holes 15, or the electrode pads 62 so as to avoid the gas holes 16, the temperature sensor holes 15, or the electrode pads 62, and both ends 81e of the arc-shaped recess 81 are formed in an R-shape.

[0047] Therefore, the openings in the screen mask corresponding to both ends 81e of the arc-shaped recess 81 become larger, and the conductive ink tends to come off from the screen mask in these areas when the driver electrode 80 is produced by screen printing. This makes it possible to prevent the conductive ink from becoming angular.

[0048] This makes it possible to prevent the conductive ink from spilling out toward the gas hole 16, the temperature sensor hole 15, or the electrode pad 62, and therefore the driver electrode 80 can be manufactured in the shape of the mask pattern (design shape) without being exposed inside the gas hole 16 or the temperature sensor hole 15. This makes it possible to prevent the distance (insulation distance) between the driver electrode 80 and the gas hole 16, the temperature sensor hole 15, or the electrode pad 62 from becoming smaller than the design value, thereby improving the insulation performance of the electrostatic chuck 1.

[0049] Furthermore, in the electrostatic chuck 1 of this embodiment, each of the positive electrode 80a and the negative electrode 80b is fan-shaped when viewed in the Z-axis direction, and both ends 84e of the arc 84 and the apex 85t of the central angle 85 are rounded. This allows the driver electrode 80 to be manufactured in the shape of the mask pattern (design shape) with even greater precision, thereby further improving the insulation performance of the electrostatic chuck 1.

[0050] In the electrostatic chuck 1 of this embodiment, the electrode pad 62 connected to the chuck electrode 50, which has the largest potential difference with the driver electrode 80, is disposed between the sector-shaped positive electrode 80a and negative electrode 80b. Specifically, an apex 85t of a central angle 85 of the positive electrode 80a and the negative electrode 80b is disposed around (surrounding) the electrode pad 62. The apex 85t forms an arc-shaped recess 81 that is recessed in an R-shape toward the electrode along the electrode pad 62.

[0051] Therefore, the conductive ink can be formed exactly according to the shape (design shape) of the mask pattern without spilling out at the top 85t, and the required insulation distance can be ensured even between the electrode pad 62 and the driver electrode 80. Therefore, it is possible to reliably prevent dielectric breakdown from occurring between the electrode pad 62 and the driver electrode 80, where the largest potential difference occurs.

[0052] Furthermore, in the electrostatic chuck 1 of this embodiment, the gas holes 16, the temperature sensor holes 15, or the electrode pads 62 are arranged between the positive electrode 80a and the negative electrode 80b, so that a reduction in the area of the driver electrode can be suppressed. As a result, even when a large number of heater electrodes 70 are provided (when a plurality of independently controllable heating zones are provided), a decrease in the allowable current amount and an increase in the resistance value of each driver electrode 80 can be suppressed.

[0053] As described above, according to the electrostatic chuck 1 of the present embodiment, the positive electrode 80a and the negative electrode 80b constituting the driver electrode 80 each have an arc-shaped recess 81 recessed (cut out) toward the electrode side along the gas hole 16, the temperature sensor hole 15, and the electrode pad 62 so as to avoid overlapping the driver electrode 80 with the gas hole 16, the temperature sensor hole 15, and the electrode pad 62 as viewed in the Z-axis direction. Both ends 81e, 81e of the arc-shaped recess 81 are formed in an R-shape (a shape obtained by R-chamfering to remove corners).

[0054] Therefore, the openings in the screen mask corresponding to the portions at both ends 81e of the arc-shaped recess 81 are enlarged, and when the driver electrode 80 is produced by screen printing, the conductive ink is easily removed from the screen mask in these portions, making it less likely that the conductive ink will become edgy. This prevents the conductive ink from spilling toward the gas hole 16, the temperature sensor hole 15, or the electrode pad 62, and allows the driver electrode 80 to be produced according to the shape (design shape) of the mask pattern without being exposed inside the gas hole 16 or the temperature sensor hole 15. This prevents the distance (insulation distance) between the driver electrode 80 and the gas hole 16, the temperature sensor hole 15, or the electrode pad 62 from being smaller than the design value, thereby improving the insulation performance of the electrostatic chuck 1.

[0055] The above-described embodiment is merely illustrative and does not limit the present disclosure in any way. Various improvements and modifications are possible without departing from the spirit and scope of the present disclosure. For example, the above-described embodiment illustrates a case in which two driver electrodes 80, 80 are provided, but the present disclosure can also be applied to a case in which one or three or more driver electrodes are provided. Furthermore, if there is one driver electrode, the positive electrode 80a and the negative electrode 80b may be semicircular rather than fan-shaped.

[0056] In addition, in the above embodiment, the gas hole 16 and the temperature sensor hole 15 are arranged between the positive electrode 80a and the negative electrode 80b, but in addition to these, a lift pin hole 17 can also be arranged.

[0057] Furthermore, in the above embodiment, the driver electrode 80 having sector-shaped electrodes 80a, 80b as the positive electrode and the negative electrode is exemplified, but the shapes of the positive electrode and the negative electrode (driver electrode) are not limited to this, and for example, as shown in FIG. 7, the present disclosure can also be applied to a driver electrode 180 having a positive electrode 180a and a negative electrode 180b that have a shape that forms part (only the outside) of a sector shape. [Explanation of symbols]

[0058] 1 Electrostatic chuck 10 Plate-like member 11 Holding surface 12 Bottom surface 15 Temperature sensor hole 16 Gas hole 17 Lift pin hole 20 Base member 30 Bonding layer 50 Chuck electrode 62 Electrode pad 70 Heater electrode 80 Driver electrode 80a Positive electrode side 80b Negative electrode side 81 Arc-shaped recess 81e Both ends 84 Arc 84e Both ends 85 Central angle 85t Top W Semiconductor wafer

Claims

1. A holding device for holding an object on a first surface, comprising: a first surface; a second surface provided on the side opposite to the first surface in the thickness direction; a heater electrode disposed between the first surface and the second surface; a driver electrode connected to the heater electrode; a hole formed in the thickness direction and opening on the second surface; and an electrode pad electrically connected to an external power source. The driver electrode has a pair of a positive electrode side electrode and a negative electrode side electrode arranged adjacent to each other in the plane direction. In the plane direction, at least one of the hole or the electrode pad is disposed between the positive electrode side electrode and the negative electrode side electrode. Each of the positive electrode side electrode and the negative electrode side electrode has an arc-shaped recess recessed toward the electrode side along the hole or the electrode pad so as to avoid the hole or the electrode pad. Both ends of the arc-shaped recess are formed in an R shape. The holding device is characterized by the above.

2. In the holding device according to Claim 1. Each of the positive electrode side electrode and the negative electrode side electrode has a semi-circular or fan-shaped shape in a view in the thickness direction, and includes at least one of an arc or a central angle. Both ends of the arc and the apex of the central angle are formed in an R shape. The holding device is characterized by the above.

3. In the holding device according to Claim 1 or Claim 2. Comprising a chuck electrode for generating an electrostatic attraction. The electrode pad is electrically connected to the chuck electrode. The holding device is characterized by the above.

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