JP2020004928A - Electrostatic chuck - Google Patents

Abstract

To improve controllability of temperature distribution on a front surface of a ceramic member.SOLUTION: An electrostatic chuck comprises: a plate-like member having a first surface nearly orthogonal to a first direction; and a plurality of heater electrodes arranged in an inner part of the plate-like member. The first surface contains: a seal band region in which a seal band formed in an annular shape in a first direction view and in a convex shape in the first direction is positioned; an inner region which is contacted to an inner side of the seal band region in the first direction view and in which a plurality of convex-like projections is formed in the first direction; and an outer region which contacts to an outer side of the seal band region in the first direction view. The plurality of heater electrodes have at least one inner heater electrode that has a part overlapped with the inner region in the first direction view, and does not have a part overlapped with the seal band region, and at least one outer heater electrode that has a part overlapped with the outer region in the first direction view, and does not have a part overlapped with the seal band region.SELECTED DRAWING: Figure 4

Description

  The technology disclosed in this specification relates to an electrostatic chuck.

  For example, an electrostatic chuck is used as a holding device for holding a wafer when manufacturing a semiconductor. The electrostatic chuck includes a plate-shaped member such as a ceramic member having a surface (hereinafter, referred to as an “upper surface”) substantially perpendicular to a predetermined direction (hereinafter, referred to as a “first direction”), and an inner portion of the plate-shaped member. And a chuck electrode provided on the upper surface of the plate-shaped member by utilizing electrostatic attraction generated by applying a voltage to the chuck electrode.

  If the temperature of the wafer held on the upper surface of the electrostatic chuck does not reach a desired temperature, the accuracy of each processing (film formation, etching, etc.) on the wafer may be reduced. Performance is required. Therefore, for example, a plurality of heater electrodes are provided inside the plate member. When a voltage is applied to each heater electrode, each heater electrode generates heat and heats the plate-like member, thereby controlling the temperature distribution on the upper surface of the plate-like member (and, consequently, the wafer held on the upper surface). Controllability of the temperature distribution) is realized.

  Further, there is known an electrostatic chuck including a heater electrode inside a plate member, wherein the first surface of the plate member includes a seal band region, an inner region, and an outer region. (For example, see Patent Document 1). In Patent Document 1, the seal band region is formed in an annular shape when viewed in the first direction. This seal band region is a region where a seal band formed in a convex shape in the first direction is located. The inner region is a region that is in contact with the inside of the seal band region when viewed in the first direction. In the inner region, a plurality of protrusions that are convex in the first direction are formed. The outer region is a region that is in contact with the outside of the seal band region when viewed in the first direction.

  In the electrostatic chuck, the heater electrode has a portion overlapping the seal band region when viewed in the first direction.

JP 2004-282047 A

  The object held by the electrostatic chuck contacts an annular and convex seal band formed in the seal band region on the upper surface of the plate member. In addition to the seal band, the object contacts a plurality of convex protrusions formed in an inner region of the upper surface of the plate-shaped member. Therefore, the heat transmitted from the heater electrode to the seal band region of the plate-shaped member where the seal band is formed and the heat transmitted to the portion of the plate-shaped member where the protrusion is formed in the inner region are reduced to the target. It is transmitted directly to the object.

  Here, the seal band formed in the seal band region is formed in an annular shape on the upper surface of the plate member. On the other hand, the plurality of protrusions formed in the inner region are independently formed. For this reason, the surface area per unit volume of the seal band is smaller than the surface area per unit volume of each projection. Due to such a difference, the seal band has a structure that is less likely to dissipate heat than the respective protrusions, and therefore the seal band region on the upper surface of the plate-like member is likely to be a high temperature singular point. In particular, when the heater electrode is disposed in a portion of the plate member that overlaps the seal band region in the first direction, the heat generated by the heater electrode is transferred to the seal band region on the upper surface of the plate member at the shortest distance. Because of the transmission, the seal band region is likely to be a higher temperature singularity. Such a seal band region contacts the object over a wider range than the respective protrusions, so that the temperature of the seal band region greatly affects the temperature of the object.

  Therefore, in the conventional electrostatic chuck, there is room for improvement in controllability of the temperature distribution on the upper surface of the plate member (and, consequently, controllability of the temperature distribution of the wafer).

  This specification discloses a technique capable of solving the above-described problem.

  The technology disclosed in this specification can be realized, for example, as the following modes.

(1) An electrostatic chuck disclosed in the present specification is a plate-shaped member having a first surface substantially orthogonal to a first direction, wherein the first surface is viewed in the first direction. A seal band region in which a seal band formed in an annular shape and convex in the first direction is located, and which is in contact with the inside of the seal band region in the first direction and in the first direction A plate-like member including: an inner region in which a plurality of convex protrusions are formed; and an outer region that contacts the outside of the seal band region when viewed in the first direction. And a plurality of heater electrodes having a heater line portion that is a linear resistance heating element as viewed in the first direction and a heater pad portion connected to an end of the heater line portion. On the first surface of the plate-like member In the electrostatic chuck for holding an object, the plurality of heater electrodes have a portion overlapping the inner region in the first direction, and at least one heater electrode having no portion overlapping the seal band region. An inner heater electrode, and at least one outer heater electrode having a portion overlapping the outer region in the first direction and not having a portion overlapping the seal band region.

  In the present electrostatic chuck, the object held by the electrostatic chuck contacts an annular and convex seal band formed in the seal band region on the first surface of the plate-shaped member. In addition to the seal band, the object contacts a plurality of convex protrusions formed in an inner region of the first surface of the plate-shaped member. Therefore, the heat transmitted from the heater electrode to the seal band region of the plate-shaped member where the seal band is formed and the heat transmitted to the portion of the plate-shaped member where the protrusion is formed in the inner region are reduced to the target. It is transmitted directly to the object. In the present electrostatic chuck, the seal band region and the inner region in the first surface of the plate member function as a suction surface for holding the object. In the following description, an area of the first surface of the plate-like member, which is a combination of the seal band area and the inner area, may be referred to as an adsorption surface.

  Here, the seal band formed in the seal band region is formed in an annular shape on the first surface of the plate-shaped member. On the other hand, the plurality of protrusions formed in the inner region are independently formed. For this reason, the surface area per unit volume of the seal band is smaller than the surface area per unit volume of each projection. Due to such a difference, the seal band has a structure that is less likely to dissipate heat than the respective protrusions. Therefore, the seal band region on the first surface of the plate-like member tends to be a high-temperature singular point. In particular, when the heater electrode is disposed in a portion of the plate-like member that overlaps the seal band region in the first direction (hereinafter, also referred to as a “seal band region overlap portion”), the heat generated by the heater electrode is: Since the light is transmitted to the seal band region on the first surface of the plate-like member at the shortest distance, the seal band region is likely to become a higher temperature singular point. Such a seal band region contacts the object over a wider range than the respective protrusions, so that the temperature of the seal band region greatly affects the temperature of the object.

  In the present electrostatic chuck, the plurality of heater electrodes disposed inside the plate member include an inner heater electrode and an outer heater electrode. The inner heater electrode is a heater electrode that has a portion overlapping the inner region and does not have a portion overlapping the seal band region when viewed in the first direction. The outer heater electrode is a heater electrode having a portion overlapping the outer region and not having a portion overlapping the seal band region when viewed in the first direction. In other words, in the present electrostatic chuck, the inner heater electrode and the outer heater electrode are arranged in a portion other than the overlapping portion of the seal band region in the plate member. For this reason, according to the present electrostatic chuck, it is possible to suppress the heat generated by the inner heater electrode and the outer heater electrode from being transmitted to the seal band area on the first surface of the plate-shaped member at the shortest distance. In addition, it is possible to prevent the seal band region in the plate-shaped member from becoming a high temperature singular point. Therefore, according to the present electrostatic chuck, the controllability of the temperature distribution on the first surface (more specifically, the suction surface) of the plate-shaped member (and, consequently, the first surface (more specifically, the suction surface)) is maintained. Controllability of the temperature distribution of the target object).

(2) In the electrostatic chuck, in the first direction, a width of the heater pad portion of the inner heater electrode is larger than a width of the heater line portion of the inner heater electrode. Direction, and in the width direction of the seal band, the seal band region, of the heater pad portions of the inner heater electrodes, the heater pad portion disposed closest to the seal band region; , At least a part of the heater line portion of the inner heater electrode may be arranged. As described above, the present electrostatic chuck employs a configuration in which the inner heater electrode and the outer heater electrode disposed inside the plate-shaped member are disposed in a portion other than the overlapping portion of the seal band region. It is possible to prevent the seal band region in the plate member from becoming a high temperature singular point. On the other hand, since the inner heater electrode and the outer heater electrode are arranged in a portion other than the overlapping portion of the seal band region, the seal band region may be a low-temperature singular point. In such a configuration, if the heater pad portion of the inner heater electrode is arranged near the overlapping portion of the seal band region, the seal band region may be a lower temperature singular point. This is because, when viewed in the first direction, the width of the heater pad portion of the inner heater electrode is larger than the width of the heater line portion of the inner heater electrode. This is because the heat value is very small as compared with the heat value.

  In the electrostatic chuck, a heater band disposed closest to the seal band region among the seal band region and the heater pad portion of the inner heater electrode in the first direction and in the width direction of the seal band. A configuration is adopted in which at least a part of the heater line portion of the inner heater electrode is disposed between the first and second portions. Therefore, according to the present electrostatic chuck, the presence of the part of the heater line portion of the inner heater electrode can prevent the seal band region in the plate-like member from being excessively low in temperature. Temperature singularities can be suppressed. Therefore, according to the present electrostatic chuck, the controllability of the temperature distribution on the first surface (more specifically, the suction surface) of the plate-shaped member (and, consequently, the first surface (more specifically, the suction surface)) is maintained. Controllability of the temperature distribution of the target object) can be further improved.

(3) In the electrostatic chuck, when viewed in the first direction, the inner side of the heater line portion of the inner heater electrode is disposed closest to the seal band region in the width direction of the seal band. The width of the first portion is the second portion of the heater line portion of the inner heater electrode which is disposed closest to the first portion of the heater line portion in the width direction of the seal band. The configuration may be smaller than the width of the portion. As described above, the present electrostatic chuck employs a configuration in which the inner heater electrode and the outer heater electrode disposed inside the plate-shaped member are disposed in a portion other than the overlapping portion of the seal band region. It is possible to prevent the seal band region in the plate member from becoming a high temperature singular point. On the other hand, since the inner heater electrode and the outer heater electrode are arranged in a portion other than the overlapping portion of the seal band region, the seal band region may be a low-temperature singular point. In such a configuration, when a heater line portion having a large width (a heater line portion having a small calorific value) is disposed near the overlapping portion of the seal band region in the plate-like member in the first direction, the seal band region is formed. Temperature singularities at lower temperatures may occur.

  In the present electrostatic chuck, when viewed in the first direction, the width of the first portion closest to the seal band region in the width direction of the seal band in the heater line portion of the inner heater electrode is: In the width direction of the seal band in the heater line portion of the inner heater electrode, a configuration is adopted which is smaller than the width of the second portion disposed closest to the first portion of the heater line portion. I have. In other words, in the present electrostatic chuck, in the heater line portion of the inner heater electrode, the calorific value of the first portion disposed closest to the overlapped portion of the seal band region in the plate member is equal to the second portion. Large compared to the calorific value. Therefore, according to the present electrostatic chuck, the presence of the first portion having a large amount of heat generated closest to the overlapping portion of the seal band region in the heater line portion of the inner heater electrode causes a plate-like shape. Since the temperature of the seal band region in the member can be suppressed from being excessively low, it is possible to prevent the seal band region from being a low temperature singular point. Therefore, according to the present electrostatic chuck, the controllability of the temperature distribution on the first surface (more specifically, the suction surface) of the plate-shaped member (and, consequently, the first surface (more specifically, the suction surface)) is maintained. Controllability of the temperature distribution of the target object) can be further improved.

(4) In the electrostatic chuck, in the first direction, a width of the heater pad portion of the outer heater electrode is larger than a width of the heater line portion of the outer heater electrode. In the directional view, a virtual straight line passing through the center point of the plate-shaped member and the one heater pad portion of the one outer heater electrode is the one heater pad portion of the one outer heater electrode, A configuration may be such that a virtual straight line passing through the heater pad portion of the inner heater electrode disposed closest to the one heater pad portion of the one outer heater electrode does not coincide with the virtual straight line passing through the heater pad portion. As described above, the present electrostatic chuck employs a configuration in which the inner heater electrode and the outer heater electrode disposed inside the plate-shaped member are disposed in a portion other than the overlapping portion of the seal band region. It is possible to prevent the seal band region in the plate member from becoming a high temperature singular point. On the other hand, since the inner heater electrode and the outer heater electrode are arranged in a portion other than the overlapping portion of the seal band region, the seal band region may be a low-temperature singular point. In such a configuration, a heater pad portion (hereinafter, also referred to as a “nearest outer heater pad portion”) of the outer heater electrode disposed closest to the overlapping portion of the seal band region in the plate member, The heater pad portion of the inner heater electrode disposed closest to the pad portion (hereinafter, also referred to as “nearest inner heater pad portion”) is the same as in the first direction and in the width direction of the seal band. When arranged on a straight line (that is, the shortest distance), the seal band region between the nearest outer heater pad and the nearest inner heater pad may have a lower temperature singularity. This is because the width of the heater pad portion of the outer heater electrode is larger than the width of the heater line portion of the outer heater electrode in the first direction, as in the case of the inner heater electrode. This is because the amount is very small as compared with the amount of heat generated in the heater line portion.

  In the present electrostatic chuck, a virtual straight line passing through the center point of the plate-shaped member and the one heater pad portion of the one outer heater electrode when viewed in the first direction is the one heater pad of the one outer heater electrode. A configuration that does not match a virtual straight line passing through the portion and the heater pad portion of the inner heater electrode disposed closest to the one heater pad portion of the one outer heater electrode is adopted. In other words, in this electrostatic chuck, the outermost heater pad portion and the innermost heater pad portion, both of which generate a small amount of heat, are aligned on the same straight line in the first direction and in the width direction of the seal band (that is, in the first direction). (Shortest distance). Therefore, according to the present electrostatic chuck, the temperature of the seal band region in the plate-shaped member can be prevented from being excessively low, and thus the temperature of the seal band region can be suppressed from being a low temperature singularity. Therefore, according to the present electrostatic chuck, the controllability of the temperature distribution on the first surface (more specifically, the suction surface) of the plate-shaped member (and, consequently, the first surface (more specifically, the suction surface)) is maintained. Controllability of the temperature distribution of the target object).

(5) In the electrostatic chuck, a width of a portion of the heater line portion of the inner heater electrode that overlaps with the protrusion in the first direction is a width of the heater line portion of the inner heater electrode. The width may be larger than the width of the portion other than the portion overlapping the protrusion when viewed in the first direction. As described above, according to the present electrostatic chuck, in addition to the seal band, since the object comes into contact with a plurality of protrusions formed in a convex shape on the inner region of the plate-like member, the same as the seal band region In addition, the heat transmitted from the inner heater electrode to the surface of the projection in contact with the object is directly transmitted to the object. For this reason, when the inner heater electrode is disposed in a portion of the plate-like member that overlaps with the projection in the first direction (projection overlapping portion), the heat generated by the inner heater electrode is the object at the projection at the shortest distance. Since the light is transmitted to the surface in contact with the object, the portion where the protrusion is formed in the inner region is likely to become a high temperature singular point. According to the electrostatic chuck of this embodiment, the width of the portion of the heater line portion of the inner heater electrode that overlaps the projection in the first direction is the same as the width of the heater line portion of the inner heater electrode in the first direction. Has a larger configuration than the width of the portion other than the portion overlapping the projection. In other words, according to the electrostatic chuck of the present embodiment, the calorific value of the portion of the heater line portion of the inner heater electrode overlapping the protrusion is smaller than the calorific value of the portion other than the portion overlapping the protrusion. Therefore, in the electrostatic chuck according to the present embodiment, since the temperature of the portion where the protrusion is formed in the inner region of the plate-like member can be suppressed from increasing, the occurrence of a high temperature singular point in the inner region can be suppressed. be able to. Therefore, in the electrostatic chuck according to the present embodiment, the controllability of the temperature distribution on the first surface (more specifically, the suction surface) of the plate-shaped member (and, consequently, the first surface (more specifically, the suction surface)) is maintained. Controllability of the temperature distribution of the target object) can be further improved.

FIG. 1 is a perspective view schematically showing an external configuration of an electrostatic chuck 100 according to the embodiment. FIG. 2 is an explanatory diagram schematically showing an XZ cross-sectional configuration of the electrostatic chuck 100 according to the embodiment. FIG. 2 is an explanatory diagram schematically showing an XY cross-sectional configuration of the electrostatic chuck 100 according to the embodiment. FIG. 3 is an explanatory diagram partially showing an XZ cross-sectional configuration of the electrostatic chuck 100. FIG. 3 is an explanatory diagram partially showing an XY cross-sectional configuration of the electrostatic chuck 100.

A. This embodiment:
A-1. Configuration of electrostatic chuck 100:
FIG. 1 is a perspective view schematically illustrating an external configuration of the electrostatic chuck 100 according to the present embodiment, and FIG. 2 is an explanatory diagram schematically illustrating an XZ cross-sectional configuration of the electrostatic chuck 100 according to the present embodiment. FIG. 3 is an explanatory view schematically showing an XY cross-sectional configuration of the electrostatic chuck 100 according to the present embodiment. FIG. 3 shows an XY cross-sectional configuration of the electrostatic chuck 100 at the position of III-III in FIG. 4 is a partially enlarged view of a part X1 in FIG. 2, and FIG. 5 is a partially enlarged view of a part X2 in FIG. Each drawing shows XYZ axes orthogonal to each other for specifying a direction. In this specification, for convenience, the positive direction of the Z axis is referred to as an upward direction, and the negative direction of the Z axis is referred to as a downward direction. However, the electrostatic chuck 100 is actually installed in a direction different from such a direction. May be done.

  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, for fixing the wafer W in a vacuum chamber of a semiconductor manufacturing apparatus. The electrostatic chuck 100 includes a ceramic member 10 and a base member 20 arranged side by side in a predetermined arrangement direction (in the present embodiment, a vertical direction (Z-axis direction)). The ceramic member 10 and the base member 20 are arranged such that the lower surface S2 of the ceramic member 10 (see FIG. 2) and the upper surface S3 of the base member 20 face each other in the arrangement direction. The ceramic member 10 corresponds to a plate-like member in the claims.

  The ceramic member 10 is a substantially disk-shaped member, and is formed of ceramics (for example, alumina, aluminum nitride, or the like). A cutout is formed on the upper side of the outer periphery of the ceramic member 10. For this reason, the upper surface S1 of the ceramic member 10 is divided into an upper stage and a lower stage. A seal band 180 that is annular in the Z-axis direction and convex in the Z-axis direction is formed on the outer periphery of the upper stage in the upper surface S1 of the ceramic member 10. The configuration of the seal band 180 will be described later in detail.

  The upper surface S1 of the ceramic member 10 includes a seal band region SR, an inner region IR, and an outer region OR. More specifically, the upper stage of the above-described upper surface S1 includes a seal band region SR and an inner region IR, and the lower stage of the upper surface S1 includes an outer region OR.

  The seal band region SR on the upper surface S1 of the ceramic member 10 is a region where the seal band 180 is located. The inner region IR is a region that is in contact with the inside of the seal band region SR when viewed in the Z-axis direction. In the inner region IR, a plurality of protrusions 170 that are convex in the Z-axis direction are formed. The configuration of the projection 170 will be described later in detail. The outer region OR is a region that is in contact with the outside of the seal band region SR when viewed in the Z-axis direction.

  The electrostatic chuck 100 places an object (for example, a wafer W) on the upper surface S1 of the ceramic member 10, more specifically, on the suction surface Sc of the upper surface S1 including the seal band region SR and the inner region IR. Hold. The suction surface Sc of the upper surface S1 of the ceramic member 10 is substantially perpendicular to the Z-axis direction, and the shape of the suction surface Sc as viewed in the Z-axis direction is substantially circular. Further, for example, a jig (not shown) for fixing the electrostatic chuck 100 is engaged with the outer region OR in the upper surface S1 of the ceramic member 10. The upper surface S1 of the ceramic member 10 corresponds to a first surface in the claims, and the Z-axis direction corresponds to a first direction in the claims. In this specification, a direction orthogonal to the Z-axis direction may be referred to as a “plane direction”.

  In the Z-axis direction, the ceramic member 10 includes a seal band overlapping portion SP that overlaps the seal band region SR, an inner region overlapping portion IP that overlaps the inner region IR, and a portion overlapping the outer region OR. And an outside area overlapping portion OP. The thickness (the thickness in the Z-axis direction, hereinafter the same) of the overlapping portion SP of the seal band region and the overlapping portion IP of the inner region in the ceramic member 10 is equal to the thickness of the notch formed in the ceramic member 10 and is equal to the outer region. It is thicker than the thickness of the overlapping portion OP. That is, the thickness of the ceramic member 10 in the Z-axis direction changes at the boundary BP between the outer region overlapping portion OP of the ceramic member 10 and the seal band region overlapping portion SP.

  The outer peripheral diameter of the seal band region overlapping portion SP of the ceramic member 10 when viewed in the Z-axis direction is, for example, about 50 mm to 500 mm (normally about 200 mm to 350 mm), and the outer peripheral diameter of the outer region overlapping portion OP of the ceramic member 10. Is, for example, about 60 mm to 510 mm (usually about 210 mm to 360 mm) (however, the diameter of the outer region overlapping portion OP is larger than the diameter of the seal band region overlapping portion SP). Further, the thickness of the seal band region overlapping portion SP and the inner region overlapping portion IP of the ceramic member 10 is, for example, about 1 mm to 10 mm, and the thickness of the outer region overlapping portion OP of the ceramic member 10 is, for example, 0.5 mm to 9 mm. It is about 5 mm (however, the thickness of the outer region overlapping portion OP is smaller than the thickness of the inner region overlapping portion IP).

  As described above, the seal band region SR on the upper surface S1 of the ceramic member 10 is a region where the seal band 180 is located. In other words, the seal band 180 is formed on the suction surface Sc of the ceramic member 10. Specifically, as shown in FIG. 3, the shape of the seal band 180 in the Z-axis direction is centered on the center point (hereinafter, also simply referred to as “center point PO”) of the suction surface Sc of the ceramic member 10. It is a continuous substantially annular shape. Further, the shape of the cross section of the seal band 180 parallel to the Z-axis direction is a substantially rectangular shape convex upward as shown in FIG. The width A1 of the seal band 180 when viewed in the Z-axis direction is, for example, about 1 mm to 5 mm. The height H1 of the seal band 180 in the Z-axis direction is, for example, about 1 mm to 3 mm. Here, the width A1 of the seal band 180 as viewed in the Z-axis direction is a width in a direction substantially perpendicular to the extending direction of the seal band 180 (“width direction D” in FIG. 4). The height H1 of the seal band 180 in the Z-axis direction is the height of the seal band 180 based on a portion of the inner region IR of the suction surface Sc where the protrusion 170 is not formed.

  As described above, a plurality of columnar projections 170 (omitted in FIGS. 1 and 2) are formed in the inner region IR of the ceramic member 10. It is preferable that the plurality of protrusions 170 are arranged at equal intervals in at least one plane direction. The shape of the tip of the projection 170 when viewed in the Z-axis direction is substantially circular as shown in FIG. Further, the shape of the projection 170 in a cross section parallel to the Z-axis direction is a substantially rectangular shape convex upward as shown in FIG. The diameter A2 of the projection 170 when viewed in the Z-axis direction is about 0.5 mm to 3 mm. The height H2 of the projection 170 in the Z-axis direction is, for example, about 1 mm to 3 mm. The height H2 of the projection 170 is substantially equal to the height H1 of the seal band 180 from the viewpoint of holding the wafer W together with the seal band 180.

  As shown in FIG. 2, a chuck electrode 40 formed of a conductive material (for example, tungsten, molybdenum, platinum, or the like) is disposed inside the ceramic member 10. The shape of the chuck electrode 40 when viewed in the Z-axis direction is, for example, substantially circular. When a voltage is applied to the chuck electrode 40 from a power supply (not shown), an electrostatic attraction is generated, and the wafer W is suction-fixed to the suction surface Sc of the ceramic member 10 by the electrostatic attraction. In a state where the wafer W is fixed to the suction surface Sc by suction, the lower surface of the wafer W contacts the top surface (upper surface) of the seal band 180 and the top surface (upper surface) of the projection 170 (see FIG. 4). Therefore, in this state, a space is formed between a region on the suction surface Sc where the seal band 180 and the projection 170 are not formed and the lower surface of the wafer W.

  Inside the ceramic member 10, a heater electrode 50 for controlling the temperature distribution of the suction surface Sc of the ceramic member 10 (that is, controlling the temperature distribution of the wafer W held on the suction surface Sc), And a configuration for supplying power to the heater electrode 50. The configuration of the heater electrode 50 will be described later in detail.

  As shown in FIG. 2, the electrostatic chuck 100 has a configuration for supplying power to each of the heater electrodes 510 and 530 constituting the plurality of heater electrodes 50. Specifically, as shown in FIG. 2, the electrostatic chuck 100 includes a driver electrode 60. The driver electrode 60 is formed of a conductive material (for example, tungsten, molybdenum, platinum, or the like). In the present embodiment, the driver electrode 60 is disposed below the heater electrode 50. The driver electrode 60 has a pair of conductive regions (a first conductive region 61 and a second conductive region 62) which are patterns having predetermined regions parallel to the plane direction.

  In the present embodiment, the inner heater electrode 510 (the inner heater electrodes 510A and 510B) is connected to the driver electrode 60. That is, as shown in FIGS. 2 and 3, with respect to the inner heater electrode 510, the first heater pad portion 513 is connected to the driver electrode 60 via the first heater-side via 721 formed of a conductive material. The second heater pad portion 515 is electrically connected to the second conductive region 62 of the driver electrode 60 via the second heater-side via 722 formed of a conductive material. are doing. Hereinafter, the first heater-side via 721 and the second heater-side via 722 are also collectively referred to as heater-side vias 721 and 722.

  As shown in FIG. 2, the electrostatic chuck 100 has a pair of terminal holes 110 and 120 extending from the lower surface S <b> 4 of the base member 20 to the inside of the ceramic member 10. Each of the terminal holes 110 and 120 includes a through hole 22 penetrating the base member 20 in the vertical direction, a through hole 32 penetrating the adhesive member 30 in the vertical direction, and a concave portion 12 formed on the lower surface S2 side of the ceramic member 10. Are integral holes formed by communicating with each other.

  A first power supply terminal 741 having a columnar shape is accommodated in the first terminal hole 110 which is one of the pair of terminal holes 110 and 120. In addition, a first electrode pad 731 is provided on the bottom surface of the concave portion 12 of the ceramic member 10 constituting the first terminal hole 110. The first power supply terminal 741 is joined to the first electrode pad 731 by, for example, brazing. Further, the first electrode pad 731 is electrically connected to the first conductive region 61 of the driver electrode 60 via the first power supply side via 711. Similarly, a second power supply terminal 742 having a columnar shape is accommodated in the second terminal hole 120 which is the other of the pair of terminal holes 110 and 120. In addition, a second electrode pad 732 is provided on the bottom surface of the concave portion 12 of the ceramic member 10 constituting the second terminal hole 120. The second power supply terminal 742 is joined to the second electrode pad 732 by, for example, brazing. Further, the second electrode pad 732 is electrically connected to the second conductive region 62 of the driver electrode 60 via the second power supply side via 712. Hereinafter, the first power supply terminal 741 and the second power supply terminal 742 are also collectively referred to as power supply terminals 741 and 742, and the first electrode pad 731 and the second electrode pad 732 are collectively referred to as the electrode pad 731. , 732, and the first power supply via 711 and the second power supply via 712 are collectively referred to as power supply vias 711, 712. The power supply terminals 741 and 742, the electrode pads 731 and 732, and the power supply-side vias 711 and 712 are all formed of a conductive material.

  In the present embodiment, as for the outer heater electrode 530, similarly to the inner heater electrode 510, the heater pad portions 533 and 535 include a pair of heater-side vias (not shown), a driver electrode 60, and a pair of power supply-side vias (not shown). (Not shown) to the electrode pads 731 and 732.

  The pair of power supply terminals 741 and 742 are connected to a power supply (not shown). With respect to the inner heater electrode 510, the voltage from the power supply is supplied to the pair of conductive regions of the driver electrode 60 via the pair of power supply terminals 741 and 742, the pair of electrode pads 731 and 732, and the pair of power supply side vias 711 and 712. It is supplied to the inner heater electrode 510 via a pair of heater-side vias 721 and 722 provided for the inner heater electrode 510. As for the outer heater electrode 530, the voltage from the power supply is supplied to the pair of driver electrodes 60 via the pair of power supply terminals 741 and 742, the pair of electrode pads 731 and 732, and the pair of power supply side vias 711 and 712. It is supplied to the conductive regions 61 and 62 and further applied to the outer heater electrode 530 via a pair of heater-side vias (not shown) provided for the outer heater electrode 530. When a voltage is applied to the inner heater electrode 510 and the outer heater electrode 530, the inner heater electrode 510 and the outer heater electrode 530 generate heat, and the ceramic member 10 is heated. (That is, the controllability of the temperature distribution of the wafer W held on the suction surface Sc) is realized.

  In the ceramic member 10 having the above-described structure, for example, a plurality of ceramic green sheets are formed, and a predetermined ceramic green sheet is subjected to processing such as formation of via holes, filling of a metallizing paste, and printing. The green sheet can be manufactured by thermocompression bonding, performing processing such as cutting, and then firing.

  The base member 20 is, for example, a plate member of a circular flat surface having the same diameter as the outer periphery of the outer region overlapping portion OP of the ceramic member 10 or having a larger diameter than the outer periphery of the outer region overlapping portion OP of the ceramic member 10. (Aluminum, aluminum alloy, etc.). The diameter of the base member 20 is, for example, about 220 mm to 550 mm (normally, 220 mm to 370 mm), and the thickness of the base member 20 is, for example, about 20 mm to 40 mm.

  The base member 20 is joined to the ceramic member 10 by an adhesive member 30 disposed between the lower surface S2 of the ceramic member 10 and the upper surface S3 of the base member 20. The adhesive member 30 is made of an adhesive such as a silicone resin, an acrylic resin, or an epoxy resin. The thickness of the bonding member 30 is, for example, about 0.1 mm to 1 mm.

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

  As shown in FIG. 2, the electrostatic chuck 100 is formed with a pin insertion hole 140 extending vertically from the lower surface S <b> 4 of the base member 20 to the suction surface Sc of the ceramic member 10. The pin insertion hole 140 is a hole for inserting a lift pin (not shown) for pushing up the wafer W held on the suction surface Sc of the ceramic member 10 and separating the wafer W from the suction surface Sc.

  Further, as shown in FIG. 2, the electrostatic chuck 100 is provided with a suction surface Sc of the ceramic member 10 in order to enhance the heat transfer between the ceramic member 10 and the wafer W to further enhance the controllability of the temperature distribution of the wafer W. A gas (for example, helium gas) is supplied to a space existing between the wafer and the surface of the wafer W. That is, the electrostatic chuck 100 has a first gas passage hole 131 extending vertically from the lower surface S <b> 4 of the base member 20 to the upper surface of the adhesive member 30, and a ceramic member which communicates with the first gas passage hole 131. A second gas flow path hole 132 is formed in the inner surface IR of the suction surface Sc in FIG. Further, a horizontal flow path 133 communicating with the second gas flow path hole 132 and extending annularly in the surface direction is formed inside the ceramic member 10, and a second gas flow path is formed on the lower surface S <b> 2 of the ceramic member 10. A recess 134 communicating with the flow path hole 132 is formed. The recess 134 is filled with a filling member (air permeable plug) 160 having air permeability. When the helium gas supplied from the helium gas source (not shown) flows into the first gas passage hole 131, the helium gas that has flowed is filled into the recess 134 from the first gas passage hole 131. After passing through the gas-permeable filling member 160, it flows into the second gas passage hole 132 inside the ceramic member 10, and flows in the surface direction via the horizontal passage 133, while adsorbing the surface Sc of the ceramic member 10. Are ejected from the gas ejection holes formed in the inner region IR. Thus, the helium gas is supplied to the space existing between the suction surface Sc and the surface of the wafer W.

A-2. Configuration of heater electrode 50, etc .:
Next, the configuration of the heater electrode 50 and the configuration for supplying power to the heater electrode 50 will be described in detail. As described above, the electrostatic chuck 100 includes the plurality of heater electrodes 50 (see FIG. 2). The heater electrode 50 is formed of a conductive material (for example, tungsten, molybdenum, platinum, or the like). In the present embodiment, the heater electrode 50 is arranged below the chuck electrode 40.

  As shown in FIG. 3, in the present embodiment, the plurality of heater electrodes 50 include two inner heater electrodes 510 (an inner heater electrode 510A and an inner heater electrode 510B) and one outer heater electrode 530. Each of the heater electrodes 510 and 530 includes a heater line portion 511, 531 which is a linear resistance heating element as viewed in the Z-axis direction, and a heater pad portion (first portion) connected to both ends of the heater line portions 511, 531. Heater pad portions 513 and 533 and second heater pad portions 515 and 535). The heater line portions 511 and 531 of each of the heater electrodes 510 and 530 have a shape that extends substantially circumferentially or substantially spirally when viewed in the Z-axis direction. Further, when viewed in the Z-axis direction, the width of the heater pad portions 513 and 515 is larger than the width of the heater line portion 511, and the width of the heater pad portions 533 and 535 is larger than the width of the heater line portion 531.

  As shown in FIGS. 3 and 4, the inner heater electrode 510 is disposed inside the inner region overlapping portion IP of the ceramic member 10. In other words, the inner heater electrode 510 has a portion overlapping the inner region IR and does not have a portion overlapping the seal band region SR when viewed in the Z-axis direction. The inner heater electrode 510 is a heater for heating the inner region IR of the suction surface Sc.

  On the other hand, the outer heater electrode 530 is arranged inside the outer area overlapping portion OP. In other words, the outer heater electrode 530 has a portion that overlaps the outer region OR and does not have a portion that overlaps the seal band region SR when viewed in the Z-axis direction. The outer heater electrode 530 is a heater for supplementarily heating the vicinity of the outer periphery of the suction surface Sc (that is, the seal band region SR and the inner region IR) where the temperature tends to be low.

  None of the heater electrodes is arranged in the overlapping portion SP of the seal band region. Therefore, the seal band region overlapping portion SP mainly includes the heater line portion 511 of the inner heater electrode 510A arranged on the outermost side of the inner heater electrode 510 and the heater line portion of the outer heater electrode 530 in the Z axis direction. The portion 531 is heated.

A-3. Positional relationship between the overlapping portion SP of the seal band region of the ceramic member 10 and the heater line portion 511 of the inner heater electrode 510A:
As shown in FIG. 3, in the Z-axis direction and in the width direction D of the seal band 180, the heater of the inner heater electrode 510 </ b> A is provided between the seal band region SR and the heater pad 515 of the inner heater electrode 510 </ b> A. A part of the line part 511 (for example, a part Px in FIG. 3) is arranged. Here, the heater pad portion 515 of the inner heater electrode 510A is positioned most in the seal band region SR among the heater pad portions 513 and 515 of the inner heater electrode 510 in the Z-axis direction and in the width direction D of the seal band 180. This is a heater pad portion that is arranged in close proximity. Similarly to the heater pad portion 515 of the inner heater electrode 510A, between the seal band region SR and the heater pad portion 513 of the inner heater electrode 510A when viewed in the Z-axis direction and in the width direction D of the seal band 180. A part of the heater line portion 511 of the inner heater electrode 510A is arranged. That is, in the Z-axis direction and in the width direction D of the seal band 180, the seal band region SR and the heater pad disposed closest to the seal band region SR among the heater pad portions of the inner heater electrodes 510. A portion of the heater line portion 511 of the inner heater electrode 510A is arranged between the portions 513 and 515.

A-4. Regarding the width of the heater line portion 511 of the inner heater electrode 510A:
In FIG. 5, for convenience, the projection 170 and the seal band 180 formed on the suction surface Sc of the upper surface S1 of the ceramic member 10 are indicated by broken lines. As shown in FIGS. 4 and 5, in the present embodiment, the width W1 of the first portion P1 of the heater line portion 511 is smaller than the width W2 of the second portion P2 of the heater line portion 511. Here, the first portion P1 of the heater line portion 511 of the inner heater electrode 510A is a portion of the heater line portion 511 of the inner heater electrode 510A that is arranged closest to the seal band overlapping portion SP. . Further, the second portion P2 of the heater line portion 511 of the inner heater electrode 510A is disposed closest to the first portion P1 of the heater line portion 511 among the heater line portions 511 of the inner heater electrode 510A. Part. Note that the width of the heater line portion 511 including the widths W1 and W2 of the heater line portion 511 means the width of the seal band 180 in the width direction D. Here, the width direction D is a substantially radial direction of the upper surface S1 of the ceramic member 10.

A-5. Positional relationship between heater pad portions 513 and 515 of inner heater electrode 510A and heater pad portions 533 and 535 of outer heater electrode 530:
FIG. 3 shows a first virtual straight line VL1 passing through the center point PO of the ceramic member 10 and the heater pad portion 535 of the outer heater electrode 530 when viewed in the Z-axis direction. FIG. 3 further shows a heater pad portion 535 of the outer heater electrode 530 and a heater pad portion 513 of the inner heater electrode 510A disposed on the outermost side of the inner heater electrode 510 when viewed in the Z-axis direction. A second virtual straight line VL2 passing through is shown. In the present embodiment, the first virtual straight line VL1 does not coincide with the second virtual straight line VL2. In other words, the heater pad portion 535 of the outer heater electrode 530 and the heater pad portion 513 of the inner heater electrode 510A are not arranged on the same straight line in the radial direction D of the ceramic member 10. Here, the heater pad portion 535 of the outer heater electrode 530 on the first virtual straight line VL1 is the heater pad portion 535 disposed closest to the seal band region overlapping portion SP on the first virtual straight line VL1. It is. The heater pad portion 513 of the inner heater electrode 510A on the second virtual straight line VL2 is arranged closest to the heater pad portion 535 of the outer heater electrode 530 among the heater pad portions 513 and 515 of the inner heater electrode 510A. The heater pad portion 513 is used.

A-6. Relationship between width of heater line portion 511 of inner heater electrode 510 and protrusion 170:
FIGS. 4 and 5 show a first portion P1, a second portion P2, and a third portion P3 of the heater line portion 511 of the inner heater electrode 510A. In the present embodiment, the width W3 of the third portion P3 of the heater line portion 511 of the inner heater electrode 510A is larger than the width W1 of the first portion P1 of the heater line portion 511 of the inner heater electrode 510A, and , Is larger than the width W2 of the second portion P2. Here, as described above, the first portion P1 of the heater line portion 511 of the inner heater electrode 510A is disposed closest to the seal band region overlapping portion SP of the heater line portion 511 of the inner heater electrode 510A. Part. The second portion P2 of the heater line portion 511 of the inner heater electrode 510A is a portion of the heater line portion 511 of the inner heater electrode 510A that is arranged closest to the first portion P1 of the heater line portion 511. is there. The third portion P3 of the heater line portion 511 of the inner heater electrode 510A is a portion that overlaps with the projection 170 when viewed in the Z-axis direction. In other words, the third portion P3 of the heater line portion 511 of the inner heater electrode 510A includes a portion overlapping the projection 170 at a portion indicated by the width A2 of the projection 170. On the other hand, the first portion P1 and the second portion P2 of the heater line portion 511 of the inner heater electrode 510A are portions other than the portion overlapping the projection 170. In other words, the first portion P1 and the second portion P2 of the heater line portion 511 of the inner heater electrode 510A do not include a portion overlapping the projection 170. The projection 170 formed on the suction surface Sc of the ceramic member 10 is indicated by a dotted line. Note that, also for the inner heater electrode 510B of the present embodiment, the width of the heater line portion 511 including the portion overlapping the protrusion 170 in the Z-axis direction is compared with the width of the heater line portion 511 not including the portion overlapping the protrusion 170. And big.

A-7. Effects of this embodiment:
As described above, the electrostatic chuck 100 according to the present embodiment includes the ceramic member 10 having the upper surface S1 that is substantially perpendicular to the Z-axis direction, and the object (the upper surface S1 of the ceramic member 10) is placed on the suction surface Sc. For example, the electrostatic chuck 100 holds the wafer W). Upper surface S1 of ceramic member 10 includes a seal band region SR, an inner region IR, and an outer region OR. The seal band region SR of the ceramic member 10 is a region where the seal band 180 formed in an annular shape in the Z-axis direction and in a convex shape in the Z-axis direction is located. The inner region IR of the ceramic member 10 is a region in contact with the inside of the seal band region SR when viewed in the Z-axis direction and in which a plurality of protrusions 170 having a convex shape in the Z-axis direction are formed. The outer region OR of the ceramic member 10 is a region in contact with the outside of the seal band region SR when viewed in the Z-axis direction. Further, the electrostatic chuck 100 of the present embodiment includes the heater electrode 50 including two inner heater electrodes 510 and the outer heater electrode 530. The inner heater electrode 510 and the outer heater electrode 530 have heater line portions 511 and 531 and heater pad portions 513, 515, 533 and 535, respectively. The two inner heater electrodes 510 (510A, 510B) have a portion that overlaps the inner region IR and does not have a portion that overlaps the seal band region SR when viewed in the Z-axis direction. In other words, the two inner heater electrodes 510 (510A, 510B) are arranged inside the inner region overlapping portion IP of the ceramic member 10. The outer heater electrode 530 has a portion overlapping the outer region OR and does not have a portion overlapping the seal band region SR when viewed in the Z-axis direction. In other words, the outer heater electrode 530 is arranged inside the outer region overlapping portion OP of the ceramic member 10.

  In the electrostatic chuck 100 of the present embodiment, the wafer W held by the electrostatic chuck 100 is in contact with the annular and convex seal band 180 formed in the seal band region SR in the upper surface S1 of the ceramic member 10. In addition to the seal band 180, the wafer W is in contact with a plurality of convex protrusions 170 formed in the inner region IR of the upper surface S1 of the ceramic member 10. Therefore, the heat transmitted from the heater electrode 50 to the seal band region SR of the ceramic member 10 where the seal band 180 is formed and the heat transmitted to the portion of the ceramic member 10 where the protrusion 170 is formed in the inner region IR. Heat is directly transmitted to the wafer W.

  Here, the seal band 180 formed in the seal band region SR is formed in an annular shape on the upper surface S1 of the ceramic member 10. On the other hand, the plurality of protrusions 170 formed in the inner region IR are independently formed. For this reason, the surface area per unit volume of the seal band 180 is smaller than the surface area per unit volume of each projection 170. Due to such a difference, the seal band 180 has a structure that is less likely to dissipate heat than the projections 170, so that the seal band region SR on the upper surface S1 of the ceramic member 10 tends to be a high temperature singular point. In particular, when the heater electrode 50 is disposed in the overlapping portion SP of the seal band region, heat generated by the heater electrode 50 is transmitted to the seal band region SR on the upper surface S1 of the ceramic member 10 at the shortest distance. The band region SR is likely to be a higher temperature singularity. Since such a seal band region SR contacts the wafer W over a wider area than the respective projections 170, the temperature of the seal band region SR greatly affects the temperature of the wafer W.

  In the electrostatic chuck 100 of the present embodiment, the plurality of heater electrodes 50 disposed inside the ceramic member 10 include the inner heater electrode 510 and the outer heater electrode 530. The inner heater electrode 510 is a heater electrode having a portion overlapping the inner region IR and not having a portion overlapping the seal band region SR when viewed in the Z-axis direction. The outer heater electrode 530 is a heater electrode having a portion overlapping the outer region OR and not having a portion overlapping the seal band region SR when viewed in the Z-axis direction. In other words, in the electrostatic chuck 100 of the present embodiment, the inner heater electrode 510 and the outer heater electrode 530 are arranged in a portion of the ceramic member 10 other than the seal band region overlapping portion SP. For this reason, according to the electrostatic chuck 100 of the present embodiment, the heat generated by the inner heater electrode 510 and the outer heater electrode 530 is prevented from being transmitted to the seal band region SR on the upper surface S1 of the ceramic member 10 at the shortest distance. As a result, it is possible to prevent the seal band region SR in the ceramic member 10 from becoming a high temperature singular point. Therefore, according to the electrostatic chuck 100 of the present embodiment, the controllability of the temperature distribution on the upper surface S1 (more specifically, the suction surface Sc) of the ceramic member 10 (therefore, the upper surface S1 (more specifically, the suction surface Sc)) is improved. The controllability of the temperature distribution of the held wafer W) can be improved.

  In the electrostatic chuck 100 of the present embodiment, the width of the heater pad portions 513 and 515 of the inner heater electrode 510 is larger than the width of the heater line portion 511 of the inner heater electrode 510 when viewed in the Z-axis direction. Further, in the Z-axis direction and in the width direction D of the seal band 180, the heater band disposed closest to the seal band region SR among the seal band region SR and the heater pad portion of the inner heater electrode 510. A portion of the heater line portion 511 of the inner heater electrode 510 (for example, a portion Px in FIG. 3) is disposed between the portion 515 and the portion 515.

  As described above, the electrostatic chuck 100 of the present embodiment has a configuration in which the inner heater electrode 510 and the outer heater electrode 530 arranged inside the ceramic member 10 are arranged in a portion other than the seal band region overlapping portion SP. By employing this, in the electrostatic chuck 100 of the present embodiment, it is possible to prevent the seal band region SR in the ceramic member 10 from becoming a high temperature singular point. On the other hand, as described above, since the inner heater electrode 510 and the outer heater electrode 530 are arranged in a portion other than the seal band region overlapping portion SP, the seal band region SR may be a low temperature singular point. In such a configuration, if the heater pad portions 513 and 515 of the inner heater electrode 510 are arranged in the vicinity of the overlapping portion SP of the seal band region, the seal band region SR may be a lower temperature singular point. This is because the width of the heater pad portions 513 and 515 of the inner heater electrode 510 is larger than the width of the heater line portion 511 of the inner heater electrode 510 when viewed in the Z-axis direction. This is because the calorific value is extremely small as compared with the calorific value in the heater line unit 511.

  In the electrostatic chuck according to the present embodiment, in the Z-axis direction and in the width direction of the seal band 180, the seal band region SR and the seal band region SR of the heater pad portions 513 and 515 of the inner heater electrode 510 are most closely located. A configuration is used in which a part of the heater line portion 511 of the inner heater electrode 510 is arranged between the heater pad portions 513 and 515 arranged close to each other. Therefore, according to the electrostatic chuck 100 of the present embodiment, the presence of the part of the heater line portion 511 of the inner heater electrode 510 can prevent the seal band region SR in the ceramic member 10 from being excessively cooled. In addition, it is possible to prevent the seal band region SR from becoming a low temperature singular point. Therefore, according to the electrostatic chuck 100 of the present embodiment, the controllability of the temperature distribution on the upper surface S1 (more specifically, the suction surface Sc) of the ceramic member 10 (therefore, the upper surface S1 (more specifically, the suction surface Sc)) is improved. The controllability of the temperature distribution of the held wafer W) can be further improved.

  In the electrostatic chuck 100 of the present embodiment, among the heater line portions 511 of the inner heater electrode 510, the electrostatic chuck 100 is disposed closest to the seal band region SR in the width direction D of the seal band 180 when viewed in the Z-axis direction. The width W1 of the first portion P1 is located closest to the first portion P1 of the heater line portion 511 in the width direction D of the seal band 180 in the heater line portion 511 of the inner heater electrode 510. It is smaller than the width W2 of the second portion P2.

  As described above, the electrostatic chuck 100 of the present embodiment has a configuration in which the inner heater electrode 510 and the outer heater electrode 530 arranged inside the ceramic member 10 are arranged in a portion other than the seal band region overlapping portion SP. By employing this, it is possible to suppress the seal band region SR in the ceramic member 10 from becoming a high temperature singular point. On the other hand, as described above, since the inner heater electrode 510 and the outer heater electrode 530 are arranged in a portion other than the seal band region overlapping portion SP, the seal band region SR may be a low temperature singular point. In such a configuration, when a heater line portion having a large width (a heater line portion having a small calorific value) is arranged near the seal band overlapping portion SP in the ceramic member 10 when viewed in the Z-axis direction, the seal band region SR May be a lower temperature singularity.

  In the present electrostatic chuck, the first portion of the heater line portion 511 of the inner heater electrode 510 which is closest to the seal band region SR in the width direction D of the seal band 180 when viewed in the Z-axis direction. The width W1 at P1 is the second portion of the heater line portion 511 of the inner heater electrode 510 that is closest to the first portion P1 of the heater line portion 511 in the width direction D of the seal band 180. A configuration smaller than the width W2 at P2 is employed. In other words, in the electrostatic chuck 100 of the present embodiment, in the heater line portion 511 of the inner heater electrode 510, the first portion P1 disposed closest to the seal band region overlapping portion SP of the ceramic member 10 is located. The heat value is larger than the heat value of the second portion P2. For this reason, according to the electrostatic chuck 100 of the present embodiment, the first heat-generating first heater heater 511 of the inner heater electrode 510 which is disposed closest to the overlapping portion SP of the seal band region is provided. Due to the presence of the portion P1, the temperature of the seal band region SR in the ceramic member 10 can be suppressed from being excessively low, so that the seal band region SR can be prevented from being a low-temperature singular point. Therefore, according to the electrostatic chuck 100 of the present embodiment, the controllability of the temperature distribution on the upper surface S1 (more specifically, the suction surface Sc) of the ceramic member 10 (and, consequently, the upper surface S1 (more specifically, the suction surface Sc)) is improved. The controllability of the temperature distribution of the held wafer W) can be further improved.

  In the electrostatic chuck 100 of the present embodiment, the width of the heater pad portions 533 and 535 of the outer heater electrode 530 is larger than the width of the heater line portion 531 of the outer heater electrode 530 when viewed in the Z-axis direction. Further, when viewed in the Z-axis direction, the first virtual straight line VL1 does not coincide with the second virtual straight line VL2.

  As described above, the electrostatic chuck 100 of the present embodiment has a configuration in which the inner heater electrode 510 and the outer heater electrode 530 arranged inside the ceramic member 10 are arranged in a portion other than the seal band region overlapping portion SP. By employing this, it is possible to suppress the seal band region SR in the ceramic member 10 from becoming a high temperature singular point. On the other hand, as described above, since the inner heater electrode 510 and the outer heater electrode 530 are arranged in a portion other than the seal band region overlapping portion SP, the seal band region SR may be a low temperature singular point. In such a configuration, the heater pad portion 535 (the outermost heater pad portion) of the outer heater electrode 530 which is arranged closest to the seal band region overlapping portion SP of the ceramic member 10 and the heater pad portion 535 (the latest heater pad portion 535) The heater pad portion 513 (closest inner heater pad portion) of the inner heater electrode 510 disposed closest to the outer heater pad portion (the outer heater pad portion) is the same as viewed in the Z-axis direction and in the width direction D of the seal band 180. When arranged on a straight line (that is, the shortest distance), the distance between the heater pad portion 535 of the outer heater electrode 530 (nearest outer heater pad portion) and the heater pad portion 513 of the inner heater electrode 510 (closest inner heater pad portion) is reduced. May have a lower temperature singularity. This is because the width of the heater pad portion 535 of the outer heater electrode 530 is larger than the width of the heater line portion 531 of the outer heater electrode 530 when viewed in the Z-axis direction, like the inner heater electrode 510. This is because the amount of heat generated by the unit 535 is very small as compared with the amount of heat generated by the heater line unit 531.

  In the electrostatic chuck 100 of the present embodiment, when viewed in the Z-axis direction, the first virtual straight line VL1 passing through the center point PO of the ceramic member 10 and the one heater pad portion 535 of the one outer heater electrode 530 is: It passes through one heater pad portion 535 of one outer heater electrode 530 and the heater pad portion 513 of the inner heater electrode 510 disposed closest to one heater pad portion 535 of one outer heater electrode 530. A configuration that does not match the second virtual straight line VL2 is employed. In other words, in the electrostatic chuck 100 of the present embodiment, the heater pad portion 535 (the latest outer heater pad portion) of the outer heater electrode 530 and the heater pad portion 513 (the latest inner heater pad) of the inner heater electrode 510 both generate a small amount of heat. ) Are not disposed on the same straight line (that is, the shortest distance) in the Z-axis direction and in the width direction D of the seal band 180. Therefore, according to the electrostatic chuck 100 of the present embodiment, the temperature of the seal band region SR in the ceramic member 10 can be suppressed from being excessively low, and thus the temperature of the seal band region SR can be suppressed to a low temperature singularity. be able to. Therefore, according to the electrostatic chuck 100 of the present embodiment, the controllability of the temperature distribution on the upper surface S1 (more specifically, the suction surface Sc) of the ceramic member 10 (and, by extension, the upper surface S1 (more specifically, the suction surface Sc) is maintained. Controllability of the temperature distribution of the processed wafer W).

  In the electrostatic chuck 100 of the present embodiment, the width of a portion of the heater line portion 511 of the inner heater electrode 510 that overlaps with the projection 170 when viewed in the Z-axis direction is the width of the Z-axis of the heater line portion 511 of the inner heater electrode 510. The width is larger than the width of a portion other than the portion overlapping with the projection 170 in the direction view.

  As described above, according to the electrostatic chuck 100 of the present embodiment, the wafer W contacts not only the seal band 180 but also the plurality of protrusions 170 formed in the inner region IR of the ceramic member 10 in a convex shape. Similarly to the seal band region SR, the heat transmitted from the inner heater electrode 510 to the surface of the protrusion 170 that contacts the W is directly transmitted to the wafer W. For this reason, when the inner heater electrode 510 is disposed in a portion (projection overlapping portion) of the ceramic member 10 that overlaps with the projection 170 when viewed in the Z-axis direction, the heat generated by the inner heater electrode 510 is generated at the shortest distance. Since the light is transmitted to the surface of the inner region IR where the protrusion 170 is formed, the portion where the protrusion 170 is formed tends to be a high temperature singular point. According to the electrostatic chuck 100 of the present embodiment, the width W3 of the heater line portion 511 of the inner heater electrode 510 overlapping the projection 170 in the Z-axis direction is equal to the width W3 of the heater line portion 511 of the inner heater electrode 510. , A configuration that is larger than the widths W1 and W2 in portions other than the portion overlapping with the projection 170 when viewed in the Z-axis direction is adopted. In other words, according to the electrostatic chuck 100 of the present embodiment, in the heater line portion 511 of the inner heater electrode 510, the heating value of the portion overlapping the projection 170 is smaller than the heating value of the portion other than the portion overlapping the projection 170. Small in comparison. Therefore, in the electrostatic chuck 100 according to the present embodiment, since the temperature of the portion where the protrusion 170 is formed in the inner region IR of the ceramic member 10 can be suppressed, a high temperature singular point occurs in the inner region IR. Can be suppressed. Therefore, in the electrostatic chuck 100 of the present embodiment, controllability of the temperature distribution on the upper surface S1 (more specifically, the suction surface Sc) of the ceramic member 10 (and, by extension, the upper surface S1 (more specifically, the suction surface Sc)) is maintained. Controllability of the temperature distribution of the wafer W) can be further improved.

B. Modification:
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 also possible.

  The configuration of the electrostatic chuck 100 of the above embodiment is merely an example, and can be variously modified. For example, in the electrostatic chuck 100 of the above-described embodiment, the notch is formed in the ceramic member 10 so that the upper surface S1 of the ceramic member 10 is formed of the upper stage formed of the seal band region SR and the inner region IR, and the outer region. Although it is divided into a lower stage composed of OR, it is not limited to this. That is, the thickness of the ceramic member 10 in the Z-axis direction may be substantially uniform in the seal band region SR, the inner region IR, and the outer region OR.

  Further, the electrostatic chuck 100 of the above-described embodiment includes a plurality of heater electrodes 50 that are substantially circumferential or spiral when viewed in the Z-axis direction, but the shape and number of the heater electrodes 50 included in the electrostatic chuck 100 are as follows. It can be arbitrarily deformed. Specifically, three or more inner heater electrodes 510 and two or more outer heater electrodes 530 may be provided.

  Further, in the electrostatic chuck 100 of the above embodiment, each of the plurality of heater electrodes 50 is electrically connected to the common pair of power supply terminals 741 and 742, but the configuration for supplying power to the plurality of heater electrodes 50 is arbitrary. Can be changed to Specifically, each of the plurality of heater electrodes 50 may be connected to a pair of power supply terminals different from each other, or only one of the pair of power supply terminals connected to the plurality of heater electrodes 50 may be connected to a plurality of power supply terminals. A power supply terminal shared with the heater electrode 50 may be used.

  Further, in the above embodiment, each via may be configured by a single via, or may be configured by a group of a plurality of vias. In the above-described embodiment, each via may have a single-layer configuration including only a via portion, or a multi-layer configuration (for example, a configuration in which a via portion, a pad portion, and a via portion are stacked). Is also good.

  Further, in the above-described embodiment, a monopolar system in which one chuck electrode 40 is provided inside the ceramic member 10 is adopted, but a bipolar system in which a pair of chuck electrodes 40 are provided inside the ceramic member 10 is used. May be employed. Further, the material forming each member in the electrostatic chuck 100 of the above embodiment is merely an example, and each member may be formed of another material.

  Further, the present invention is not limited to the electrostatic chuck 100 including the ceramic member 10, but is also applicable to an electrostatic chuck including a plate-shaped member formed of a material other than ceramics (eg, resin).

10: Ceramics member 12: Concave portion 20: Base member 21: Refrigerant channel 22: Through hole 30: Adhesive member 32: Through hole 40: Chuck electrode 50: Heater electrode 60: Driver electrode 61: First conductive region 62: First 2 conductive region 100: electrostatic chuck 110: first terminal hole 120: second terminal hole 131: first gas passage hole 132: second gas passage hole 133: lateral passage 134: concave portion 140: Pin insertion hole 160: Filling member 170: Projection 180: Seal band 510: Inner heater electrode 510A: Inner heater electrode 510B: Inner heater electrode 511: Heater line section 513: First heater pad section 515: Second heater Pad section 530: outer heater electrode 531: heater line section 533: first heater pad section 535: 2nd heater pad part 711: 1st power supply side via 712: 2nd power supply side via 721: 1st heater side via 722: 2nd heater side via 731: 1st electrode pad 732: 2nd Electrode pad 741: First power supply terminal 742: Second power supply terminal BP: Boundary IP: Inner area overlapping part IR: Inner area OP: Outer area overlapping part OR: Outer area P1: First part P2: Second part Part P3: Third part PO: Center point S1: Upper surface S2: Lower surface S3: Upper surface S4: Lower surface SP: Seal band region overlapping portion SR: Seal band region Sc: Suction surface W: Wafer

Claims (5)

A plate-like member having a first surface substantially orthogonal to a first direction,
The first surface is
A seal band region in which a seal band formed in a ring shape in the first direction and convex in the first direction is located;
An inner region in contact with the inside of the seal band region when viewed in the first direction, and in which a plurality of protrusions that are convex in the first direction are formed;
An outer region that is in contact with the outer side of the seal band region in the first direction view;
A plate-like member,
A heater line portion that is disposed inside the plate-shaped member and that is a linear resistance heating element as viewed in the first direction and has a heater pad portion connected to an end of the heater line portion; A plurality of heater electrodes;
In the electrostatic chuck for holding an object on the first surface of the plate-shaped member,
The plurality of heater electrodes,
In the first direction view, at least one inner heater electrode having a portion overlapping the inner region and having no portion overlapping the seal band region;
In the first direction view, at least one outer heater electrode having a portion overlapping the outer region and having no portion overlapping the seal band region;
An electrostatic chuck comprising: The electrostatic chuck according to claim 1,
In the first direction, the width of the heater pad portion of the inner heater electrode is larger than the width of the heater line portion of the inner heater electrode,
In the first direction, and in the width direction of the seal band, the seal band region and the heater disposed closest to the seal band region in the heater pad portion of the inner heater electrode. Between the pad portion, at least a portion of the heater line portion of the inner heater electrode is disposed,
An electrostatic chuck characterized in that: The electrostatic chuck according to claim 1 or 2,
In the first direction, the width of the first portion of the heater line portion of the inner heater electrode that is closest to the seal band region in the width direction of the seal band is the width. Of the heater line portion of the inner heater electrode, in the width direction of the seal band, smaller than the width of the second portion of the heater line portion disposed closest to the first portion,
An electrostatic chuck characterized in that: The electrostatic chuck according to any one of claims 1 to 3,
In the first direction, a width of the heater pad portion of the outer heater electrode is larger than a width of the heater line portion of the outer heater electrode,
In the first direction view, a virtual straight line passing through the center point of the plate-shaped member and the one heater pad of the one outer heater electrode is the one heater pad of the one outer heater electrode. A virtual straight line passing through the portion and the heater pad portion of the inner heater electrode disposed closest to the one heater pad portion of the one outer heater electrode.
An electrostatic chuck characterized in that: In the electrostatic chuck according to any one of claims 1 to 4,
The width of a portion of the heater line portion of the inner heater electrode that overlaps with the protrusion in the first direction as viewed from the protrusion in the heater line portion of the inner heater electrode in the first direction. Larger than the width of the part other than the overlapping part,
An electrostatic chuck characterized in that:

Images