Electrostatic chuck

Abstract

To provide an electrostatic chuck capable of improving uniformity of temperature distribution in a plane of an object to be processed by reducing complexity of temperature control.SOLUTION: An electrostatic chuck comprises a ceramic dielectric substrate, a base plate, and a heater part. The heater part comprises first and second power feeding parts and a heater line. An extension part of the heater line comprises a first extension part adjacent to the first power feeding part and a second extension part adjacent to the second power feeding part. The first extension part comprises a first portion overlapping the first power feeding part, a second portion overlapping the second power feeding part, and a third portion not overlapping the first and second power feeding parts. The second extension part comprises a fourth portion overlapping the first power feeding part, a fifth portion overlapping the second power feeding part, and a sixth portion not overlapping the first and second power feeding parts. Each of a third distance between a first virtual tangent in contact with the first and second power feeding parts and the first extension part and a fourth distance between a second virtual tangent in contact with the first and second power feeding parts and the second extension part is less than or equal to a first distance between the first and second power feeding parts and less than or equal to a second distance between the extension parts.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] Aspects of the present invention generally relate to electrostatic chucks. [Background technology]

[0002] Electrostatic chucks are used in plasma processing chambers for etching, CVD (Chemical Vapor Deposition), sputtering, ion implantation, ashing, etc. to attract and hold objects to be processed, such as semiconductor wafers and glass substrates. Electrostatic chucks apply electrostatic attraction power to built-in electrodes to attract substrates, such as silicon wafers, by electrostatic force.

[0003] In recent years, there has been a demand for miniaturization and increased processing speed in IC chips containing semiconductor elements such as transistors. Accordingly, there is a demand for improved processing accuracy, such as etching, when forming semiconductor elements on wafers. Etching processing accuracy refers to whether or not wafer processing can form patterns with the designed width and depth. By improving processing accuracy, such as etching, semiconductor elements can be miniaturized and their integration density can be increased. In other words, improving processing accuracy enables chips to be made smaller and faster.

[0004] It is known that the accuracy of processing such as etching depends on the temperature of the wafer during processing. Therefore, in a substrate processing apparatus having an electrostatic chuck, it is required to control the temperature distribution within the wafer surface during processing in order to uniformize the etching rate. As a method for controlling the temperature distribution within the wafer surface, a method using an electrostatic chuck with a built-in heater (heat generating element) is known (for example, Patent Document 1).

[0005] In particular, in recent years, with the miniaturization of semiconductor elements, there has been a demand for faster heating and more precise control of in-plane temperature distribution, and one known means of achieving this is to use a heater with a two-layer structure consisting of a main heater and a sub-heater (for example, Patent Document 2). Heater patterns when configuring a heater with multiple zones are also known (for example, Patent Document 3). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-168818 [Patent Document 2] Japanese Patent Application Laid-Open No. 2014-529826 [Patent Document 3] Japanese Patent Application Publication No. 2019-149434 Summary of the Invention [Problem to be solved by the invention]

[0007] However, while providing multiple zones in a heater allows for more precise temperature control, it also creates new issues, such as design constraints on the shape of the heater pattern and an increase in the number of pads and terminals for power supply, which can result in the creation of many cool spots with relatively low temperatures within the heater surface, reducing the uniformity of the temperature distribution within the wafer surface.

[0008] Therefore, it is conceivable to improve the uniformity of the temperature distribution within the wafer surface by dispersing the cool spots within the heater surface. However, dispersing the cool spots within the heater surface may complicate temperature control. There is a need to improve the uniformity of the temperature distribution within the wafer surface while preventing temperature control from becoming too complicated.

[0009] The present invention has been made based on the recognition of such problems, and aims to provide an electrostatic chuck that can improve the uniformity of the temperature distribution within the surface of the object to be processed while preventing temperature control from becoming complicated. [Means for solving the problem]

[0010] A first invention provides a ceramic dielectric substrate having a first main surface on which an object to be processed is placed and a second main surface opposite to the first main surface, a base plate supporting the ceramic dielectric substrate, and a heater section for heating the ceramic dielectric substrate, the heater section having a first power supply section, a second power supply section adjacent to the first power supply section, and a heater line which is an electrode connecting the first power supply section and the second power supply section and generates heat when a current flows through it, the heater line extending along a first direction and extending in a second direction perpendicular to the first direction. the plurality of extension portions include a first extension portion adjacent to the first power feed portion and the second power feed portion on one side in the second direction, and a second extension portion adjacent to the first power feed portion and the second power feed portion on the other side in the second direction, and the first extension portion has a first portion overlapping with the first power feed portion in the second direction, a second portion overlapping with the second power feed portion in the second direction, and a second portion positioned between the first portion and the second portion in the first direction and not overlapping with the first power feed portion and the second power feed portion in the second direction. the second extension portion has a fourth portion overlapping with the first power feed portion in the second direction, a fifth portion overlapping with the second power feed portion in the second direction, and a sixth portion located between the fourth portion and the fifth portion in the first direction and not overlapping with the first power feed portion and the second power feed portion in the second direction, a first distance being a minimum distance between the first power feed portion and the second power feed portion in the first direction, a second distance being a minimum distance between the plurality of extension portions in the second direction, a third distance is a distance in the second direction between a first virtual tangent line tangent to the first power supply portion and the second power supply portion on the one side of the second direction and the first extension portion, and a fourth distance is a distance in the second direction between a second virtual tangent line tangent to the first power supply portion and the second power supply portion on the other side of the second direction along the first direction and the second extension portion, the third distance and the fourth distance are each less than or equal to the first distance, and the third distance and the fourth distance are each less than or equal to the second distance.

[0011] Because the first and second power feeders do not generate heat, they can become cool spots, which can reduce the uniformity of the temperature distribution within the surface of the workpiece. To improve the uniformity of the temperature distribution within the surface of the heater unit, for example, it is possible to arrange the first and second power feeders at positions distant from each other. However, if the first and second power feeders are arranged at positions distant from each other, the cool spots may be dispersed, complicating temperature control. On the other hand, if the first and second power feeders are arranged close to each other, the temperature at the cool spots may be lowered, which may reduce the uniformity of the temperature distribution within the surface of the heater unit. In contrast, with this electrostatic chuck, the first and second power feeders are arranged close to each other, and the portions of the heater line adjacent to the first and second power feeders (first extension portion and second extension portion) are arranged near the first and second power feeders. This prevents the dispersion of the cool spots, and by arranging the heater lines (first and second extensions) near the cool spots, it is possible to prevent the temperature at the cool spots from dropping significantly. Therefore, it is possible to improve the uniformity of the temperature distribution within the surface of the processing object while preventing temperature control from becoming complicated.

[0012] A second invention is an electrostatic chuck according to the first invention, wherein the heater section has a plurality of zones, the plurality of zones including a first zone including the first power supply section, the second power supply section, and the heater line, the first zone having a central region located in the center of the first zone and a peripheral region located outside the central region when viewed along a Z direction perpendicular to the first main surface, and the first power supply section and the second power supply section are provided in the central region.

[0013] According to this electrostatic chuck, the first and second power feeders, which tend to have a lower temperature than the heater line when the heater unit is heated, are provided in the central region, which tends to have a higher temperature than the peripheral region, thereby improving the uniformity of the temperature distribution within the surface of the first zone, thereby improving the uniformity of the temperature distribution within the surface of the processing object.

[0014] A third invention is an electrostatic chuck according to the first invention, wherein the heater unit has a plurality of zones, and the plurality of zones include a first zone including the first power supply unit, the second power supply unit, and the heater line, and the first zone includes an outer peripheral edge of the heater unit, and the first zone has an inner peripheral portion located radially inward of a radial center line that divides the first zone into two equal parts in the radial direction, and an outer peripheral portion located radially outward of the radial center line and including the outer peripheral edge, and the first power supply unit and the second power supply unit are provided on the inner peripheral portion.

[0015] The temperature of the outermost portion of the processing object tends to be lower than that of the inner portion. With this electrostatic chuck, when the first zone includes the outer periphery of the heater unit (i.e., in the first zone located at the outermost periphery of the heater unit), the first power supply unit and the second power supply unit, which tend to be lower in temperature than the heater line when the heater unit is heated, are provided in the inner periphery of the first zone, thereby improving the uniformity of the temperature distribution within the surface of the processing object.

[0016] A fourth invention is an electrostatic chuck according to any one of the first to third inventions, wherein the first direction is a circumferential direction.

[0017] In this electrostatic chuck, the first direction is set to the circumferential direction, which makes it easier to arrange the extension portions regularly. This makes it possible to more reliably reduce the second distance. Therefore, it is possible to improve the uniformity of the temperature distribution within the surface of the processing object.

[0018] A fifth invention is an electrostatic chuck according to any one of the first to third inventions, wherein the first direction is a radial direction.

[0019] According to this electrostatic chuck, the first direction is set to the radial direction, which makes it easier to arrange the extension portions regularly. This makes it possible to more reliably reduce the second distance. Therefore, it is possible to improve the uniformity of the temperature distribution within the surface of the processing object. [Effects of the Invention]

[0020] According to an aspect of the present invention, an electrostatic chuck is provided that can improve the uniformity of the temperature distribution within the surface of a processing object while suppressing the complexity of temperature control. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a perspective view schematically illustrating an electrostatic chuck according to an embodiment. [Figure 2] 2(a) and 2(b) are cross-sectional views schematically illustrating a part of an electrostatic chuck according to an embodiment. [Figure 3] FIG. 2 is an exploded perspective view schematically illustrating a heater portion according to the embodiment. [Figure 4] FIG. 2 is an exploded cross-sectional view schematically illustrating a heater portion according to the embodiment. [Figure 5] FIG. 4 is a plan view schematically showing a main zone of a second heater element according to the embodiment. [Figure 6] FIG. 3 is a plan view schematically showing a subzone of a first heater element according to the embodiment. [Figure 7] FIG. 4 is a plan view schematically showing the positional relationship between the main zone of the second heater element and the sub-zone of the first heater element according to the embodiment. [Figure 8] FIG. 2 is a plan view schematically showing a first zone of the heater unit according to the first embodiment. [Figure 9] FIG. 10 is a plan view schematically showing a first zone of a heater portion according to a second embodiment. [Figure 10] FIG. 10 is a plan view schematically showing a first zone of a heater portion according to a third embodiment. [Figure 11] FIG. 10 is a plan view schematically illustrating a part of a first zone of a heater portion according to a modified example of the embodiment. [Figure 12] FIG. 10 is a plan view schematically illustrating a part of a first zone of a heater portion according to a modified example of the embodiment. [Figure 13] FIG. 10 is a plan view schematically illustrating a part of a first zone of a heater portion according to a modified example of the embodiment. [Figure 14] FIG. 10 is a plan view schematically illustrating a part of a first zone of a heater portion according to a modified example of the embodiment. [Figure 15] FIG. 10 is a plan view schematically showing a first zone of a conventional heater section. [Figure 16] 16(a) and 16(b) are graphs showing the simulation results of the temperature distribution in the first zone of the heater section. [Figure 17] FIG. 2 is a plan view schematically illustrating a first zone of a heater unit according to the embodiment. [Figure 18] FIG. 10 is a plan view schematically illustrating a first zone of a heater portion according to a modified example of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, like components are designated by like reference numerals and detailed descriptions thereof will be omitted where appropriate.

[0023] FIG. 1 is a perspective view schematically illustrating an electrostatic chuck according to an embodiment. 2(a) and 2(b) are cross-sectional views schematically illustrating a part of an electrostatic chuck according to an embodiment. For convenience of explanation, FIG. 1 shows a cross-sectional view of a part of the electrostatic chuck. FIG. 2(a) is a cross-sectional view taken along the line A1-A2 shown in FIG. Fig. 2(b) is an enlarged view of region B1 shown in Fig. 2(a). Note that the processing object W is omitted in Fig. 2(b).

[0024] As shown in FIGS. 1, 2(a), and 2(b), the electrostatic chuck 10 according to the embodiment includes a ceramic dielectric substrate 100, a heater portion 200, and a base plate 300.

[0025] The ceramic dielectric substrate 100 is a flat base material made of, for example, a polycrystalline ceramic sintered body, and has a first main surface 101 on which a processing object W such as a semiconductor wafer is placed, and a second main surface 102 opposite to the first main surface 101.

[0026] In this specification, the direction perpendicular to the first main surface 101 is defined as the Z direction. In other words, the Z direction is the direction connecting the first main surface 101 and the second main surface 102. In other words, the Z direction is the direction from the base plate 300 toward the ceramic dielectric substrate 100. One of the directions perpendicular to the Z direction is defined as the X direction, and the direction perpendicular to the Z direction and the X direction is defined as the Y direction. In this specification, "in-plane" refers to, for example, the XY plane. In this specification, "planar view" refers to a state viewed along the Z direction.

[0027] Examples of the crystalline material contained in the ceramic dielectric substrate 100 include Al2O3, AlN, SiC, Y2O3, and YAG. By using such materials, the infrared transmittance, thermal conductivity, insulation resistance, and plasma durability of the ceramic dielectric substrate 100 can be improved.

[0028] An electrode layer 111 is provided inside the ceramic dielectric substrate 100. The electrode layer 111 is interposed between the first main surface 101 and the second main surface 102. In other words, the electrode layer 111 is formed so as to be inserted into the ceramic dielectric substrate 100. The electrode layer 111 is sintered integrally with the ceramic dielectric substrate 100.

[0029] The electrode layer 111 is not limited to being interposed between the first main surface 101 and the second main surface 102, but may be provided on the second main surface 102.

[0030] The electrostatic chuck 10 applies an attracting and holding voltage to the electrode layer 111 to generate an electric charge on the first main surface 101 side of the electrode layer 111, and attracts and holds the workpiece W by electrostatic force.

[0031] The electrode layer 111 is provided along the first main surface 101 and the second main surface 102. The electrode layer 111 is an adsorption electrode for adsorbing and holding the processing target W. The electrode layer 111 may be a monopolar or bipolar type. The electrode layer 111 may also be a tripolar or other multipolar type. The number of electrode layers 111 and the arrangement of the electrode layers 111 are selected appropriately.

[0032] The base plate 300 is provided on the second main surface 102 side of the ceramic dielectric substrate 100 and supports the ceramic dielectric substrate 100. The base plate 300 is provided with a communication path 301. In other words, the communication path 301 is provided inside the base plate 300. Examples of materials for the base plate 300 include aluminum, aluminum alloys, titanium, and titanium alloys.

[0033] The base plate 300 serves to adjust the temperature of the ceramic dielectric substrate 100. For example, when cooling the ceramic dielectric substrate 100, a cooling medium is introduced into the communicating passages 301, passed through the communicating passages 301, and then discharged from the communicating passages 301. This allows the cooling medium to absorb heat from the base plate 300, thereby cooling the ceramic dielectric substrate 100 mounted thereon.

[0034] Furthermore, convex portions 113 are provided on the first main surface 101 side of the ceramic dielectric substrate 100 as needed. Grooves 115 are provided between adjacent convex portions 113. The grooves 115 communicate with each other. A space is formed between the grooves 115 and the back surface of the processing object W mounted on the electrostatic chuck 10.

[0035] An introduction path 321 that penetrates the base plate 300 and the ceramic dielectric substrate 100 is connected to the groove 115. When a transfer gas such as helium (He) is introduced from the introduction path 321 while the processing object W is held by suction, the transfer gas flows into the space provided between the processing object W and the groove 115, and the processing object W can be directly heated or cooled by the transfer gas.

[0036] The heater section 200 heats the ceramic dielectric substrate 100. The heater section 200 heats the ceramic dielectric substrate 100, thereby heating the processing object W via the ceramic dielectric substrate 100. In this example, the heater section 200 is provided between the first main surface 101 and the second main surface 102. That is, the heater section 200 is formed so as to be inserted into the ceramic dielectric substrate 100. In other words, the heater section 200 is built into the ceramic dielectric substrate 100.

[0037] The heater section 200 may be provided separately from the ceramic dielectric substrate 100. In this case, the heater section 200 is provided, for example, between the ceramic dielectric substrate 100 and the base plate 300 via an adhesive layer. Examples of materials for the adhesive layer include heat-resistant resins such as silicone that have relatively high thermal conductivity.

[0038] FIG. 3 is an exploded perspective view schematically illustrating a heater portion according to the embodiment. FIG. 4 is an exploded cross-sectional view schematically illustrating a heater portion according to the embodiment. As shown in Figures 3 and 4, in this example, the heater section 200 has a first support plate 210, a first insulating layer 220, a first heater element 231, a second insulating layer 240, a second heater element 232, a third insulating layer 245, a bypass layer 250, a fourth insulating layer 260, a second support plate 270, and a power supply terminal 280.

[0039] The first support plate 210 is provided on the first heater element 231, the second heater element 232, the bypass layer 250, etc. The second support plate 270 is provided below the first heater element 231, the second heater element 232, the bypass layer 250, etc. A surface 211 (upper surface) of the first support plate 210 forms the upper surface of the heater section 200. A surface 271 (lower surface) of the second support plate 270 forms the lower surface of the heater section 200. When the heater section 200 is built into the ceramic dielectric substrate 100, the first support plate 210 and the second support plate 270 may be omitted.

[0040] The first support plate 210 and the second support plate 270 are support plates that support the first heater element 231, the second heater element 232, etc. In this example, the first support plate 210 and the second support plate 270 sandwich and support the first insulating layer 220, the first heater element 231, the second insulating layer 240, the second heater element 232, the third insulating layer 245, the bypass layer 250, and the fourth insulating layer 260.

[0041] The first insulating layer 220 is provided between the first support plate 210 and the second support plate 270. The first heater element 231 is provided between the first insulating layer 220 and the second support plate 270. In this manner, the first heater element 231 is provided overlapping the first support plate 210. In other words, the first insulating layer 220 is provided between the first support plate 210 and the first heater element 231. When the heater section 200 is built into the ceramic dielectric substrate 100, the ceramic dielectric substrate 100 also serves as the first insulating layer 220.

[0042] The second insulating layer 240 is provided between the first heater element 231 and the second support plate 270. The second heater element 232 is provided between the second insulating layer 240 and the second support plate 270. In this manner, the second heater element 232 is provided in a layer different from the layer in which the first heater element 231 is provided. At least a portion of the second heater element 232 overlaps the first heater element 231 in the Z direction. The third insulating layer 245 is provided between the second heater element 232 and the second support plate 270. The bypass layer 250 is provided between the third insulating layer 245 and the second support plate 270. The fourth insulating layer 260 is provided between the bypass layer 250 and the second support plate 270.

[0043] In other words, the first heater element 231 is provided between the first insulating layer 220 and the second insulating layer 240. In other words, the second heater element 232 is provided between the second insulating layer 240 and the third insulating layer 245. In other words, the bypass layer 250 is provided between the third insulating layer 245 and the fourth insulating layer 260.

[0044] The first heater element 231, for example, contacts the first insulating layer 220 and the second insulating layer 240. The second heater element 232, for example, contacts the second insulating layer 240 and the third insulating layer 245. The bypass layer 250, for example, contacts the third insulating layer 245 and the fourth insulating layer 260.

[0045] The bypass layer 250 and the fourth insulating layer 260 are provided as necessary and can be omitted. If the bypass layer 250 and the fourth insulating layer 260 are not provided, the third insulating layer 245 comes into contact with the second support plate 270. The following description will be given taking as an example a case where the heater section 200 has the bypass layer 250 and the fourth insulating layer 260.

[0046] The first support plate 210 has a relatively high thermal conductivity. For example, the thermal conductivity of the first support plate 210 is higher than that of the first heater element 231 and higher than that of the second heater element 232. Examples of materials for the first support plate 210 include metals containing at least one of aluminum, copper, and nickel, and multilayer graphite. The thickness (length in the Z direction) of the first support plate 210 is, for example, approximately 0.1 mm or more and 3.0 mm or less. More preferably, the thickness of the first support plate 210 is, for example, approximately 0.3 mm or more and 1.0 mm or less. The first support plate 210 improves the uniformity of the temperature distribution within the surface of the heater section 200. The first support plate 210 functions, for example, as a heat spreader plate. The first support plate 210 suppresses warping of the heater section 200. The first support plate 210 improves the adhesive strength between the heater section 200 and the ceramic dielectric substrate 100.

[0047] The material, thickness, and function of the second support plate 270 are the same as those of the first support plate 210. For example, the thermal conductivity of the second support plate 270 is higher than that of the first heater element 231 and higher than that of the second heater element 232. In the embodiment, at least one of the first support plate 210 and the second support plate 270 may be omitted.

[0048] The first insulating layer 220 may be made of an insulating material such as resin or ceramic. Examples of resin materials for the first insulating layer 220 include polyimide and polyamideimide. Examples of ceramic materials for the first insulating layer 220 include Al2O3, AlN, SiC, Y2O3, and YAG. The thickness (length in the Z direction) of the first insulating layer 220 is, for example, approximately 0.01 mm or more and 0.20 mm or less. The first insulating layer 220 bonds the first support plate 210 and the first heater element 231. The first insulating layer 220 electrically insulates the first support plate 210 and the first heater element 231. Thus, the first insulating layer 220 has both an electrical insulating function and a surface-bonding function. The first insulating layer 220 is only required to have at least an insulating function, and may also have other functions such as a heat conducting function and a diffusion preventing function.

[0049] The material and thickness of the second insulating layer 240 are approximately the same as those of the first insulating layer 220. The material and thickness of the third insulating layer 245 are approximately the same as those of the first insulating layer 220. The material and thickness of the fourth insulating layer 260 are approximately the same as those of the first insulating layer 220.

[0050] The second insulating layer 240 joins the first heater element 231 and the second heater element 232. The second insulating layer 240 electrically insulates the first heater element 231 and the second heater element 232. In this way, the second insulating layer 240 has an electrical insulating function and a surface-to-surface bonding function. Note that the second insulating layer 240 only needs to have at least an insulating function, and may also have other functions such as a heat conducting function and a diffusion preventing function.

[0051] The third insulating layer 245 joins the second heater element 232 and the bypass layer 250. The third insulating layer 245 electrically insulates the second heater element 232 and the bypass layer 250. In this way, the third insulating layer 245 has an electrical insulating function and a surface-to-surface bonding function. Note that the third insulating layer 245 only needs to have at least an insulating function, and may also have other functions such as a heat conducting function and a diffusion preventing function.

[0052] The fourth insulating layer 260 joins the bypass layer 250 and the second support plate 270. The fourth insulating layer 260 electrically insulates the bypass layer 250 and the second support plate 270. In this way, the fourth insulating layer 260 has an electrical insulating function and a surface-to-surface bonding function. Note that the fourth insulating layer 260 only needs to have at least an insulating function, and may also have other functions such as a heat conducting function and a diffusion preventing function.

[0053] Examples of materials for the first heater element 231 include metals containing at least one of stainless steel, titanium, chromium, nickel, copper, aluminum, Inconel (registered trademark), nickel, molybdenum, tungsten, palladium, platinum, silver, tantalum, molybdenum carbide, and tungsten carbide. The thickness (length in the Z direction) of the first heater element 231 is, for example, approximately 0.01 mm or more and 0.20 mm or less. The material and thickness of the second heater element 232 are approximately the same as those of the first heater element 231. The first heater element 231 and the second heater element 232 are, for example, electrically connected to the bypass layer 250. On the other hand, the first heater element 231 and the second heater element 232 are electrically insulated from the first support plate 210 and the second support plate 270, respectively.

[0054] The first heater element 231 and the second heater element 232 each generate heat when a current flows therethrough. The first heater element 231 and the second heater element 232 generate heat to heat the ceramic dielectric substrate 100. The first heater element 231 and the second heater element 232 heat the processing object W, for example, via the ceramic dielectric substrate 100, thereby making the temperature distribution within the surface of the processing object W uniform. Alternatively, the first heater element 231 and the second heater element 232 can intentionally make a difference in the temperature within the surface of the processing object W, for example, by heating the processing object W via the ceramic dielectric substrate 100.

[0055] The bypass layer 250 is disposed approximately parallel to the first support plate 210 and approximately parallel to the second support plate 270. The bypass layer 250 has a plurality of bypass sections 251. In this example, the bypass layer 250 has ten bypass sections 251 (bypass sections 251a to 251j). The number of bypass sections 251 is not limited to "10". The bypass layer 250 has a plate shape.

[0056] The bypass layer 250 has, for example, electrical conductivity. The bypass layer 250 is, for example, electrically connected to the first heater element 231 and the second heater element 232. The bypass layer 250 is a power supply path for the first heater element 231 and the second heater element 232. On the other hand, the bypass layer 250 is electrically insulated from, for example, the first support plate 210 and the second support plate 270 by an insulating layer.

[0057] The thickness of the bypass layer 250 (length in the Z direction) is, for example, approximately 0.03 mm or more and 0.30 mm or less. The thickness of the bypass layer 250 is thicker than the thickness of the first insulating layer 220. The thickness of the bypass layer 250 is thicker than the thickness of the second insulating layer 240. The thickness of the bypass layer 250 is thicker than the thickness of the third insulating layer 245. The thickness of the bypass layer 250 is thicker than the thickness of the fourth insulating layer 260.

[0058] For example, the material of the bypass layer 250 is the same as the material of the first heater element 231 and the second heater element 232. On the other hand, the thickness of the bypass layer 250 is thicker than the thickness of the first heater element 231 and thicker than the thickness of the second heater element 232. Therefore, the electrical resistance of the bypass layer 250 is lower than the electrical resistance of the first heater element 231 and lower than the electrical resistance of the second heater element 232. This makes it possible to prevent the bypass layer 250 from generating heat like the first heater element 231 and the second heater element 232, even if the material of the bypass layer 250 is the same as the material of the first heater element 231 and the second heater element 232. In other words, the electrical resistance of the bypass layer 250 can be reduced, and the amount of heat generated by the bypass layer 250 can be reduced.

[0059] Note that the means for reducing the electrical resistance of the bypass layer 250 and the amount of heat generated by the bypass layer 250 may be achieved by using a material with a relatively low volume resistivity, rather than by increasing the thickness of the bypass layer 250. That is, the material of the bypass layer 250 may be different from the material of the first heater element 231 and the second heater element 232. Examples of materials for the bypass layer 250 include metals containing at least one of stainless steel, titanium, chromium, nickel, copper, and aluminum.

[0060] The power supply terminal 280 is electrically connected to the bypass layer 250. When the heater section 200 is provided between the base plate 300 and the ceramic dielectric substrate 100, the power supply terminal 280 is provided from the heater section 200 toward the base plate 300. The power supply terminal 280 supplies power supplied from outside the electrostatic chuck 10 to the first heater element 231 and the second heater element 232 via the bypass layer 250. The power supply terminal 280 may be directly connected to the first heater element 231 and the second heater element 232, for example. This makes it possible to omit the bypass layer 250.

[0061] On the other hand, when the first heater element 231 and / or the second heater element 232 has a large number of zones, for example, 20 or more, 50 or more, or 100 or more, it becomes difficult to arrange the power supply terminals 280 corresponding to each zone. By providing the bypass layer 250, the degree of freedom in arranging the power supply terminals 280 is improved compared to when the power supply terminals 280 are arranged for each zone.

[0062] The heater section 200 has a plurality of power supply terminals 280. In this example, the heater section 200 has ten power supply terminals 280 (power supply terminals 280a to 280j). The number of power supply terminals 280 is not limited to "10". One power supply terminal 280 is electrically connected to one bypass section 251. In other words, the number of power supply terminals 280 is the same as the number of bypass sections 251. The hole 273 penetrates the second support plate 270. The power supply terminal 280 is electrically connected to the bypass section 251 through the hole 273.

[0063] The first heater element 231 has a first region 701 and a second region 702. The first region 701 and the second region 702 each have a first sub-power feeder 231a, a second sub-power feeder 231b, and a sub-heater line 231c. The sub-heater line 231c is electrically connected to the first sub-power feeder 231a and the second sub-power feeder 231b. The first sub-power feeder 231a is provided at one end of the sub-heater line 231c, and the second sub-power feeder 231b is provided at the other end of the sub-heater line 231c. The sub-heater line 231c generates heat when a current flows through it. The first sub-power feeder 231a and the second sub-power feeder 231b supply power to the sub-heater line 231c. The first heater element 231 is electrically connected to the bypass layer 250 at the first sub-power feeding portion 231a and the second sub-power feeding portion 231b.

[0064] As indicated by arrows C21 and C22 in Fig. 4, when power is supplied to the power supply terminal 280a from outside the electrostatic chuck 10, current flows from the power supply terminal 280a to the bypass portion 251a. As indicated by arrows C23 and C24 in Fig. 4, the current flowing to the bypass portion 251a flows from the bypass portion 251a to the first region 701 of the first heater element 231. As indicated by arrows C25 and C26 in Fig. 4, the current flowing to the first region 701 flows from the first region 701 to the bypass portion 251b. More specifically, the current flowing to the bypass portion 251a flows to the sub-heater line 231c of the first region 701 via the first sub-power supply portion 231a of the first region 701, and then flows to the bypass portion 251b via the second sub-power supply portion 231b of the first region 701. As indicated by arrows C27 and C28 in Fig. 4, the current flowing to the bypass portion 251b flows from the bypass portion 251b to the power supply terminal 280b. As indicated by arrow C29 in Fig. 4, the current flowing to the power supply terminal 280b flows to the outside of the electrostatic chuck 10.

[0065] Similarly, when power is supplied to the power supply terminal 280c from outside the electrostatic chuck 10, current flows in the order of the power supply terminal 280c, the bypass portion 251c, the second region 702 of the first heater element 231, the bypass portion 251d, and the power supply terminal 280d, as shown by arrows C31 to C39 in FIG. 4.

[0066] The second heater element 232 has a main zone 601, a main zone 602, and a main zone 603. Each of the main zones 601 to 603 has a first main power feeder 232a, a second main power feeder 232b, and a main heater line 232c. The main heater line 232c is electrically connected to the first main power feeder 232a and the second main power feeder 232b. The first main power feeder 232a is provided at one end of the main heater line 232c, and the second main power feeder 232b is provided at the other end of the main heater line 232c. The main heater line 232c generates heat when a current flows through it. The first main power feeder 232a and the second main power feeder 232b feed power to the main heater line 232c. The second heater element 232 is electrically connected to the bypass layer 250 at the first main power feed portion 232a and the second main power feed portion 232b.

[0067] As indicated by arrows C41 and C42 in Fig. 4, when power is supplied to the power supply terminal 280e from outside the electrostatic chuck 10, current flows from the power supply terminal 280e to the bypass portion 251e. As indicated by arrows C43 and C44 in Fig. 4, the current flowing to the bypass portion 251e flows from the bypass portion 251e to the main zone 601 of the second heater element 232. As indicated by arrows C45 and C426 in Fig. 4, the current flowing to the main zone 601 flows from the main zone 601 to the bypass portion 251f. More specifically, the current flowing to the bypass portion 251e flows to the main heater line 232c of the main zone 601 via the first main power supply portion 232a of the main zone 601 and then flows to the bypass portion 251f via the second main power supply portion 232b of the main zone 601. As indicated by arrows C47 and C48 in Fig. 4, the current flowing to the bypass portion 251f flows from the bypass portion 251f to the power supply terminal 280f. As indicated by arrow C49 in Fig. 4, the current flowing to the power supply terminal 280f flows to the outside of the electrostatic chuck 10.

[0068] Similarly, when power is supplied to the power supply terminal 280g from outside the electrostatic chuck 10, current flows in the order of the power supply terminal 280g, the bypass portion 251g, the main zone 602 of the second heater element 232, the bypass portion 251h, and the power supply terminal 280h, as shown by arrows C51 to C59.

[0069] Similarly, when power is supplied to the power supply terminal 280i from outside the electrostatic chuck 10, current flows in the order of the power supply terminal 280i, the bypass portion 251i, the main zone 603 of the second heater element 232, the bypass portion 251j, and the power supply terminal 280j, as shown by arrows C61 to C69.

[0070] For example, the current flowing through the first heater element 231 and the current flowing through the second heater element 232 are controlled separately. In this example, the bypass section 251 (bypass sections 251a, 251b, 251c, and 251d) connected to the first heater element 231 and the bypass section 251 (bypass sections 251e, 251f, 251g, 251h, 251i, and 251j) connected to the second heater element 232 are different from each other. The bypass section 251 connected to the first heater element 231 and the bypass section 251 connected to the second heater element 232 may be the same.

[0071] For example, by differentiating the voltage applied to the power supply terminals 280 (power supply terminals 280a, 280b, 280c, 280d) that supply power to the first heater element 231 from the voltage applied to the power supply terminals 280 (power supply terminals 280e, 280f, 280g, 280h, 280i, 280j) that supply power to the second heater element 232, it is possible to make the output of the first heater element 231 and the output of the second heater element 232 different. In other words, it is possible to control the output of each heater element independently.

[0072] For example, the current flowing through the first region 701 and the current flowing through the second region 702 of the first heater element 231 are controlled separately. In this example, the bypass section 251 (bypass sections 251a and 251b) connected to the first region 701 and the bypass section 251 (bypass sections 251c and 251d) connected to the second region 702 are different from each other. The bypass section 251 connected to the first region 701 and the bypass section 251 connected to the second region 702 may be the same.

[0073] For example, by differentiating the voltage applied to power supply terminals 280 (power supply terminals 280a and 280b) that supply power to first region 701 from the voltage applied to power supply terminals 280 (power supply terminals 280c and 280d) that supply power to second region 702, it is possible to make the output of first region 701 and the output of second region 702 different. In other words, it is possible to control the output of each region (subzone) independently.

[0074] For example, the current flowing through the main zone 601 of the second heater element 232, the current flowing through the main zone 602, and the current flowing through the main zone 603 are controlled separately. In this example, the bypass section 251 (bypass sections 251e and 251f) connected to the main zone 601, the bypass section 251 (bypass sections 251g and 251h) connected to the main zone 602, and the bypass section 251 (bypass sections 251i and 251j) connected to the main zone 603 are all different. The bypass section 251 connected to the main zone 601, the bypass section 251 connected to the main zone 602, and the bypass section 251 connected to the main zone 603 may be the same.

[0075] For example, by differentiating the voltage applied to power supply terminal 280 (power supply terminals 280e, 280f) that supplies power to main zone 601, the voltage applied to power supply terminal 280 (power supply terminals 280g, 280h) that supplies power to main zone 602, and the voltage applied to power supply terminal 280 (power supply terminals 280i, 280j) that supplies power to main zone 603, it is possible to make the output of main zone 601, the output of main zone 602, and the output of main zone 603 different. In other words, it is possible to control the output of each main zone independently.

[0076] The first heater element 231 generates less heat than the second heater element 232. That is, the first heater element 231 is a low-output sub-heater, and the second heater element 232 is a high-output main heater.

[0077] In this way, the first heater element 231 generates less heat than the second heater element 232, so that the first heater element 231 can suppress temperature unevenness within the surface of the processing object W caused by the pattern of the second heater element 232. Therefore, the uniformity of the temperature distribution within the surface of the processing object W can be improved.

[0078] The volume resistivity of the first heater element 231 is higher than the volume resistivity of the second heater element 232, for example. The volume resistivity of the first heater element 231 is the volume resistivity of the sub-heater line 231c. That is, the volume resistivity of the first heater element 231 is the volume resistivity between the first sub-power feeder 231a and the second sub-power feeder 231b. In other words, the volume resistivity of the first heater element 231 is the volume resistivity in the paths indicated by arrows C25 and C35 in FIG. 4. Similarly, the volume resistivity of the second heater element 232 is the volume resistivity of the main heater line 232c. That is, the volume resistivity of the second heater element 232 is the volume resistivity between the first main power feeder 232a and the second main power feeder 232b. In other words, the volume resistivity of the second heater element 232 is the volume resistivity in the paths indicated by the arrows C45, C55, and C65 in FIG.

[0079] In this way, by making the volume resistivity of the first heater element 231 higher than that of the second heater element 232, the output (heat generation amount, power consumption) of the first heater element 231 can be made lower than the output (heat generation amount, power consumption) of the second heater element 232. This makes it possible for the first heater element 231 to suppress temperature unevenness within the surface of the processing object W caused by the pattern of the second heater element 232. Therefore, it is possible to improve the uniformity of the temperature distribution within the surface of the processing object.

[0080] The area around the power supply terminal 280 is likely to become a temperature singular point (a point where the temperature is relatively significantly different from the surrounding area). In response to this, the provision of the bypass layer 250 increases the degree of freedom in arranging the power supply terminal 280. For example, the power supply terminals 280 that are likely to become temperature singular points can be arranged in a dispersed manner, making it easier for heat to diffuse around the singular points. This improves the uniformity of the temperature distribution within the surface of the processing object W.

[0081] By providing the bypass layer 250, it is possible to configure the heater section 200 so that the power supply terminals 280, which have a large heat capacity, are not directly connected to the first heater element 231 and the second heater element 232. This can improve the uniformity of the temperature distribution within the surface of the processing object W. Furthermore, by providing the bypass layer 250, it is not necessary to directly connect the power supply terminals 280 to the first heater element 231 and the second heater element 232, which are relatively thin. This can improve the reliability of the heater section 200.

[0082] As described above, the power supply terminal 280 is provided from the heater unit 200 toward the base plate 300. Therefore, power can be supplied to the power supply terminal 280 from the lower surface 303 (see FIGS. 2(a) and 2(b)) side of the base plate 300 via a member called a socket or the like. This allows wiring of the heater to be realized while preventing the power supply terminal 280 from being exposed in the chamber in which the electrostatic chuck 10 is installed.

[0083] In this example, the first heater element 231 is located higher than the second heater element 232. In other words, the first heater element 231 is provided between the second heater element 232 and the first main surface 101. The positions of the first heater element 231 and the second heater element 232 may be reversed. That is, the second heater element 232 may be located higher than the first heater element 231. In other words, the second heater element 232 may be provided between the first main surface 101 and the first heater element 231. From the viewpoint of temperature control, it is preferable that the first heater element 231 be located higher than the second heater element 232.

[0084] When the first heater element 231 is positioned higher than the second heater element 232, the distance between the first heater element 231 and the processing object W is shorter than the distance between the second heater element 232 and the processing object W. Since the first heater element 231 is relatively close to the processing object W, the first heater element 231 can more easily control the temperature of the processing object W. That is, the first heater element 231 can more easily suppress temperature unevenness within the surface of the processing object W that occurs due to the pattern of the second heater element 232. Therefore, the uniformity of the temperature distribution within the surface of the processing object W can be improved.

[0085] On the other hand, when the second heater element 232 is positioned higher than the first heater element 231, the high-output second heater element 232 is relatively close to the processing object W. This can improve the temperature response (rate of temperature increase and rate of temperature decrease) of the processing object W.

[0086] In this example, the second heater element 232 is provided between the bypass layer 250 and the first heater element 231 in the Z direction. In other words, the bypass layer 250 is located below the first heater element 231 and the second heater element 232.

[0087] In this way, by providing the second heater element 232 between the bypass layer 250 and the first heater element 231 in the Z direction, the first heater element 231 and the second heater element 232 can be arranged on one side of the bypass layer 250. As a result, when connecting the power supply terminal 280 to the bypass layer 250, the power supply terminal 280 can be connected to the bypass layer 250 from the side opposite to the first heater element 231 and the second heater element 232. Therefore, there is no need to provide holes in the first heater element 231 and the second heater element 232 for passing the power supply terminal 280, which makes it possible to reduce temperature singularities on the heater pattern and improve the uniformity of the temperature distribution within the surfaces of the first heater element 231 and the second heater element 232.

[0088] The bypass layer 250 may be located above the first heater element 231 and the second heater element 232. That is, the bypass layer 250 may be provided between the first support plate 210 and the first heater element 231. The bypass layer 250 may also be provided between the first support plate 210 and the second heater element 232. The bypass layer 250 may also be located between the first heater element 231 and the second heater element 232.

[0089] Furthermore, the number of heater elements included in the heater section 200 is not limited to two. That is, the heater section 200 may further include another heater element provided in a layer different from the first heater element 231 and the second heater element 232. Furthermore, the heater section 200 may include only one of the first heater element 231 and the second heater element 232. That is, either the first heater element 231 or the second heater element 232 may be omitted.

[0090] FIG. 5 is a plan view schematically showing the main zone of the second heater element according to the first embodiment. FIG. 5 is a diagram of the second heater element 232 shown in FIG. 3 projected onto a plane perpendicular to the Z direction. 5, the second heater element 232 has a plurality of main zones 600 divided in the radial direction Dr. In the second heater element 232, for example, each main zone 600 is subjected to independent temperature control. In this specification, the "radial direction Dr" is the direction from the center of the heater element toward the outer periphery along the radius, and the "circumferential direction Dc" is the direction along the outer periphery of the heater element.

[0091] In this example, the multiple main zones 600 include three main zones 601 to 603 aligned in the radial direction Dr. That is, the second heater element 232 is divided into three in the radial direction Dr. The main zones 600 are arranged in the order of main zone 601, main zone 602, and main zone 603 from the center CT2 of the second heater element 232 outward in the radial direction Dr.

[0092] In this example, the main zone 601 is circular and centered at a center CT2 in a planar view. The main zone 602 is annular and located outside the main zone 601 and centered at the center CT2 in a planar view. The main zone 603 is annular and located outside the main zone 602 and centered at the center CT2 in a planar view.

[0093] In this example, the width LM1 in the radial direction Dr of the main zone 601, the width LM2 in the radial direction Dr of the main zone 602, and the width LM3 in the radial direction Dr of the main zone 603 are all the same. The widths LM1 to LM3 may be different from each other.

[0094] The number of main zones 600 and the shape in plan view of the main zones 600 may be arbitrary. The main zones 600 may be divided in the circumferential direction Dc, or may be divided in the circumferential direction Dc and the radial direction Dr.

[0095] The main heater lines 232c constituting each main zone 600 are independent of each other. This allows a different voltage to be applied to each main zone 600 (main heater line 232c). Therefore, the output (amount of heat generated) can be controlled independently for each main zone 600. In other words, each main zone 600 is a heater unit capable of performing temperature control independently of each other, and the second heater element 232 is an assembly of heater units having a plurality of such heater units.

[0096] As described above, each main zone 600 has one first main power feeder 232a, one second main power feeder 232b, and one main heater line 232c. The main heater line 232c is an electrode connecting the first main power feeder 232a and the second main power feeder 232b, and generates heat when a current flows through it. The main zone 600 is an area formed by the continuous main heater line 232c connecting the first main power feeder 232a and the second main power feeder 232b.

[0097] 5, for convenience, the ends of the main zones 600 in the radial direction Dr are shown as being in contact with each other, but in reality, there are gaps between them (i.e., portions where the main heater lines 232c are not provided), and the ends of adjacent main zones in the radial direction Dr do not come into contact with each other. This also applies to the subsequent figures.

[0098] FIG. 6 is a plan view schematically showing a subzone of the first heater element according to the first embodiment. FIG. 6 is a diagram of the first heater element 231 shown in FIG. 3 projected onto a plane perpendicular to the Z direction. 6, in this example, the first heater element 231 has a plurality of sub-zones 700 divided in the radial direction Dr and the circumferential direction Dc. In the first heater element 231, the temperature of each sub-zone 700 is independently controlled.

[0099] The multiple subzones 700 include a first region 701 consisting of subzones 701a to 701f lined up in the circumferential direction Dc, and a second region 702 consisting of subzones 702a to 702f lined up in the circumferential direction Dc. That is, the second heater element 232 is divided into two in the radial direction Dr. Furthermore, the first region 701 and the second region 702 are each divided into six in the circumferential direction Dc. The regions are arranged in this order from the center CT1 of the first heater element 231 outward in the radial direction Dr: the first region 701, then the second region 702.

[0100] The first region 701 has a circular shape centered on a center CT1 in plan view. The second region 702 has an annular shape centered on the center CT1 and is located outside the first region 701 in plan view.

[0101] The first area 701 has subzones 701a to 701f. In the first area 701, the subzones 701a to 701f are arranged in the following order clockwise: subzone 701a, subzone 701b, subzone 701c, subzone 701d, subzone 701e, and subzone 701f. Each of the subzones 701a to 701f constitutes a part of the circular first area 701.

[0102] The second region 702 has subzones 702a to 702f. In the second region 702, the subzones 702a to 702f are arranged clockwise in the following order: subzone 702a, subzone 702b, subzone 702c, subzone 702d, subzone 702e, and subzone 702f. In this example, subzone 702a is located outside subzone 701a. Subzone 702b is located outside subzone 701b. Subzone 702c is located outside subzone 701c. Subzone 702d is located outside subzone 701d. Subzone 702e is located outside subzone 701e. Subzone 702f is located outside subzone 701f. Each of the subzones 702a to 702f constitutes a part of the annular second region 702.

[0103] The width LS1 of the first region 701 in the radial direction Dr and the width LS2 of the second region 702 in the radial direction Dr are, for example, the same. The width LS1 and the width LS2 may be different.

[0104] The number of the sub-zones 700 is, for example, greater than the number of the main zones 600. That is, the first heater element 231 is divided into more zones than the second heater element 232. The number of the sub-zones 700 may be the same as the number of the main zones 600, or may be less than the number of the main zones 600.

[0105] By making the number of sub-zones 700 included in the first heater element 231 greater than the number of main zones 600 included in the second heater element 232, the first heater element 231 can adjust the temperature in a smaller area than the second heater element 232. This makes it possible to use the first heater element 231 to perform more precise temperature adjustments, thereby improving the uniformity of the temperature distribution within the surface of the processing object W.

[0106] The number of subzones 700 and the shape of the subzones 700 in plan view may be arbitrary. Furthermore, the subzones 700 do not have to be divided in the circumferential direction Dc. In other words, the first region 701 and the second region 702 do not have to include multiple subzones 700 divided in the circumferential direction Dc.

[0107] The sub-heater lines 231c constituting each sub-zone 700 are independent of each other. This allows a different voltage to be applied to each sub-zone 700 (sub-heater line 231c). Therefore, the output (amount of heat generated) can be controlled independently for each sub-zone 700. In other words, each sub-zone 700 is a heater unit capable of performing temperature control independently of each other, and the first heater element 231 is an assembly of heater units having a plurality of such heater units.

[0108] As described above, each subzone 700 has one first sub-power supply portion 231a, one second sub-power supply portion 231b, and one sub-heater line 231c. The sub-heater line 231c is an electrode connecting the first sub-power supply portion 231a and the second sub-power supply portion 231b, and generates heat when a current flows through it. The subzone 700 is an area formed by the continuous sub-heater line 231c connecting the first sub-power supply portion 231a and the second sub-power supply portion 231b.

[0109] 6, for convenience, the ends of the sub-zones 700 in the radial direction Dr are shown as being in contact with each other, but in reality, there are gaps between them (i.e., portions where the sub-heater lines 231c are not provided), and the ends of adjacent sub-zones 700 in the radial direction Dr do not come into contact with each other. This also applies to the subsequent figures.

[0110] FIG. 7 is a plan view schematically showing the positional relationship between the main zone of the second heater element and the sub-zone of the first heater element according to the embodiment. FIG. 7 shows the positional relationship when the second heater element 232 shown in FIG. 5 and the first heater element 231 shown in FIG. 6 are superimposed and viewed along the Z direction. In FIG. 7, the main zone 600 of the second heater element 232 is indicated by a two-dot chain line, and the sub-zone 700 of the first heater element 231 is indicated by a solid line.

[0111] 7, the first heater element 231 and the second heater element 232 are arranged such that, for example, a center CT1 of the first heater element 231 and a center CT2 of the second heater element 232 overlap in the Z direction. Also, the outer circumferential edge 231e of the first heater element 231 and the outer circumferential edge 232e of the second heater element 232 overlap in the Z direction. The outer circumferential edge 231e of the first heater element 231 and the outer circumferential edge 232e of the second heater element 232 do not have to overlap in the Z direction.

[0112] FIG. 8 is a plan view schematically illustrating the first zone of the heater portion according to the first embodiment. 8 shows an enlarged view of the first zone 810 of the heater section 200. The first zone 810 is one of multiple zones included in the heater section 200. The first zone 810 may be, for example, one of the sub-zones 700 of the first heater element 231, or one of the main zones 600 of the second heater element 232.

[0113] 8, the first zone 810 includes a first power feeder 831, a second power feeder 832, and a heater line 833. When the first zone 810 is one of the subzones 700, the first power feeder 831, the second power feeder 832, and the heater line 833 are the first sub-power feeder 231a, the second sub-power feeder 231b, and the sub-heater line 231c, respectively. When the first zone 810 is one of the main zones 600, the first power feeder 831, the second power feeder 832, and the heater line 833 are the first main power feeder 232a, the second main power feeder 232b, and the main heater line 232c, respectively.

[0114] The second power supply part 832 is provided at a position adjacent to the first power supply part 831. In other words, the heater line 833 is not provided between the first power supply part 831 and the second power supply part 832. In other words, the heater line 833 is provided so as to avoid the space between the first power supply part 831 and the second power supply part 832.

[0115] The heater line 833 has a plurality of extending portions 834 and a folded portion 835. The heater line 833 has a structure in which the plurality of extending portions 834 are connected by the folded portion 835. As a result, the heater line 833 functions as a single electrode connecting the first power supply portion 831 and the second power supply portion 832.

[0116] The extending portions 834 extend along a first direction. The extending portions 834 are lined up in a second direction. The second direction is a direction perpendicular to the first direction. In this example, the first direction is the circumferential direction Dc, and the second direction is the radial direction Dr. That is, the extending portions 834 extend along the circumferential direction Dc and are lined up in the radial direction Dr.

[0117] The multiple extending portions 834 include a first extending portion 841 and a second extending portion 842. The first extending portion 841 is adjacent to the first power feeding portion 831 and the second power feeding portion 832 on one side (outside) in the second direction (radial direction Dr). That is, no other extending portion 834 is provided between the first extending portion 841 and the first power feeding portion 831 and between the first extending portion 841 and the second power feeding portion 832. The second extending portion 842 is adjacent to the first power feeding portion 831 and the second power feeding portion 832 on the other side (inside) in the second direction (radial direction Dr). That is, no other extending portion 834 is provided between the second extending portion 842 and the first power feeding portion 831 and between the second extending portion 842 and the second power feeding portion 832.

[0118] The first extending portion 841 has a first portion 841a, a second portion 841b, and a third portion 841c. The first portion 841a overlaps with the first power feeding portion 831 in the second direction (radial direction Dr). The second portion 841b overlaps with the second power feeding portion 832 in the second direction (radial direction Dr). The third portion 841c is located between the first portion 841a and the second portion 841b in the first direction (circumferential direction Dc). The third portion 841c does not overlap with the first power feeding portion 831 or the second power feeding portion 832 in the second direction (radial direction Dr). In other words, the third portion 841c overlaps with the gap between the first power feeding portion 831 and the second power feeding portion 832 in the second direction (radial direction Dr).

[0119] The second extending portion 842 has a fourth portion 842a, a fifth portion 842b, and a sixth portion 842c. The fourth portion 842a overlaps with the first power feeding portion 831 in the second direction (radial direction Dr). The fifth portion 842b overlaps with the second power feeding portion 832 in the second direction (radial direction Dr). The sixth portion 842c is located between the fourth portion 842a and the fifth portion 842b in the first direction (circumferential direction Dc). The sixth portion 842c does not overlap with the first power feeding portion 831 or the second power feeding portion 832 in the second direction (radial direction Dr). In other words, the sixth portion 842c overlaps with the gap between the first power feeding portion 831 and the second power feeding portion 832 in the second direction (radial direction Dr).

[0120] The fourth portion 842a overlaps with the first portion 841a in the second direction (radial direction Dr). A portion of the first power supply portion 831 is located between the first portion 841a and the fourth portion 842a in the second direction (radial direction Dr). The fifth portion 842b overlaps with the second portion 841b in the second direction (radial direction Dr). A portion of the second power supply portion 832 is located between the second portion 841b and the fifth portion 842b in the second direction (radial direction Dr). The sixth portion 842c overlaps with the third portion 841c in the second direction (radial direction Dr). The first power supply portion 831 and the second power supply portion 832 are not provided between the third portion 841c and the sixth portion 842c in the second direction (radial direction Dr). That is, the gap between the first power supply portion 831 and the second power supply portion 832 is located between the third portion 841c and the sixth portion 842c in the second direction (radial direction Dr).

[0121] The first power supply portion 831 is connected to a first portion 841a of the first extending portion 841 via a first connecting portion 836. The first connecting portion 836 extends from the first power supply portion 831 toward one side (outside) in the second direction (radial direction Dr). In addition, a second portion 841b of the first extending portion 841 is connected to a second curved portion 839 that follows the outer shape of the second power supply portion 832.

[0122] The second power supply portion 832 is connected to a fifth portion 842b of the second extending portion 842 via a second connecting portion 837. The second connecting portion 837 extends from the second power supply portion 832 toward the other side (inner side) in the second direction (radial direction Dr). In this manner, the second connecting portion 837 extends, for example, on the opposite side from the first connecting portion 836. In addition, the fourth portion 842a of the second extending portion 842 is connected to a first curved portion 838 that follows the outer shape of the first power supply portion 831.

[0123] The minimum distance in the first direction (circumferential direction Dc) between the first power supply portion 831 and the second power supply portion 832 is defined as the first distance L1. The minimum distance in the second direction (radial direction Dr) between the plurality of extension portions 834 is defined as the second distance L2. The second distance L2 is, for example, the same as the first distance L1. It is preferable to make the first distance L1 shorter than the second distance L2, so that the first power supply portion 831 and the second power supply portion 832, which may become cool spots, can be brought sufficiently close to each other. Note that the distance in the second direction between the plurality of extension portions 834 does not need to be constant. In this case, the minimum distance among the distances in the second direction between the plurality of extension portions 834 is defined as the second distance L2. The first distance L1 is, for example, not less than 0.1 mm and not more than 2.0 mm. The second distance L2 is, for example, not less than 0.2 mm and not more than 2.0 mm.

[0124] The distance in the second direction (radial direction Dr) between the first imaginary tangent VT1 and the first extension portion 841 is defined as a third distance L3. The first imaginary tangent VT1 is a tangent that runs along the first direction (circumferential direction Dc) and is tangent to the first power supply portion 831 and the second power supply portion 832 on one side (outside) in the second direction (radial direction Dr). The third distance L3 is, for example, the distance in the second direction (radial direction Dr) between the first imaginary tangent VT1 and the third portion 841c of the first extension portion 841. The third distance L3 is equal to or less than the first distance L1. The third distance L3 is, for example, shorter than the first distance L1. The third distance L3 is, for example, longer than half the first distance L1. The third distance L3 is equal to or less than the second distance L2. The third distance L3 is, for example, shorter than the second distance L2. The third distance L3 is, for example, not less than 0.05 mm and not more than 0.6 mm, and preferably not less than 0.1 mm and not more than 0.3 mm.

[0125] The distance in the second direction (radial direction Dr) between the second imaginary tangent VT2 and the second extension portion 842 is defined as a fourth distance L4. The second imaginary tangent VT2 is a tangent that runs along the first direction (circumferential direction Dc) and is tangent to the first power supply portion 831 and the second power supply portion 832 on the other side (inner side) in the second direction (radial direction Dr). The fourth distance L4 is, for example, the distance in the second direction (radial direction Dr) between the second imaginary tangent VT2 and the sixth portion 842c of the second extension portion 842. The fourth distance L4 is equal to or less than the first distance L1. The fourth distance L4 is, for example, shorter than the first distance L1. The fourth distance L4 is, for example, longer than half the first distance L1. The fourth distance L4 is equal to or less than the second distance L2. The fourth distance L4 is, for example, shorter than the second distance L2. The fourth distance L4 is, for example, longer than half the second distance L2. The fourth distance L4 is, for example, not less than 0.04 mm and not more than 0.6 mm. The fourth distance L4 is preferably, for example, the same as the third distance L3. The fourth distance L4 may be longer or shorter than the third distance L3.

[0126] Because the first power supply unit 831 and the second power supply unit 832 do not generate heat, they may form cool spots with relatively low temperatures within the surface of the heater unit 200, which may reduce the uniformity of the temperature distribution within the surface of the workpiece W. In order to improve the uniformity of the temperature distribution within the surface of the heater unit 200, for example, it is conceivable to arrange the first power supply unit 831 and the second power supply unit 832 at positions distant from each other. However, if the first power supply unit 831 and the second power supply unit 832 are arranged at positions distant from each other, the cool spots may be dispersed, which may complicate temperature control. On the other hand, if the first power supply unit 831 and the second power supply unit 832 are arranged at positions close to each other, the temperature at the cool spots may become lower, which may reduce the uniformity of the temperature distribution within the surface of the heater unit 200.

[0127] In contrast, in the electrostatic chuck 10 according to the embodiment, the first power supply portion 831 and the second power supply portion 832 are disposed close to each other, and the portions of the heater line 833 adjacent to the first power supply portion 831 and the second power supply portion 832 (the first extension portion 841 and the second extension portion 842) are disposed close to the first power supply portion 831 and the second power supply portion 832. More specifically, the third distance L3 and the fourth distance L4 are set equal to or less than the first distance L1 and equal to or less than the second distance L2, respectively. This prevents the cool spot from being dispersed, and by disposing the heater line 833 (the first extension portion 841 and the second extension portion 842), which is a heat-generating portion, near the cool spot, a significant drop in temperature at the cool spot can be prevented. Therefore, the uniformity of the temperature distribution within the surface of the processing object W can be improved while preventing temperature control from becoming complicated.

[0128] FIG. 9 is a plan view schematically showing the first zone of the heater portion according to the second embodiment. 9, in this example, the first connecting portion 836 extends from the first power feeding portion 831 toward the other side (inner side) in the second direction (radial direction Dr). The first power feeding portion 831 is not directly connected to the first extending portion 841. In other words, the first connecting portion 836 is not directly connected to the first extending portion 841. The first connecting portion 836 is connected to a first curved portion 838 that follows the outer shape of the first power feeding portion 831.

[0129] Furthermore, the second connection portion 837 extends from the second power supply portion 832 toward the other side (inner side) in the second direction (radial direction Dr). In this way, the second connection portion 837 may extend, for example, to the same side as the first power supply portion 831. The second power supply portion 832 is not directly connected to the second extending portion 842. In other words, the second connection portion 837 is not directly connected to the second extending portion 842. The second connection portion 837 is not directly connected to the first curved portion 838 that follows the outer shape of the second power supply portion 832.

[0130] In this example as well, the third distance L3 and the fourth distance L4 are each equal to or less than the first distance L1. Furthermore, the third distance L3 and the fourth distance L4 are each equal to or less than the second distance L2. In this example as well, by arranging the first power supply part 831 and the second power supply part 832 in positions close to each other and arranging the parts of the heater line 833 adjacent to the first power supply part 831 and the second power supply part 832 (the first extension part 841 and the second extension part 842) near the first power supply part 831 and the second power supply part 832, it is possible to improve the uniformity of the temperature distribution within the surface of the treatment object W while preventing temperature control from becoming complicated.

[0131] FIG. 10 is a plan view schematically illustrating the first zone of the heater portion according to the third embodiment. 10, in this example, the first direction is the radial direction Dr, and the second direction is the circumferential direction Dc. That is, the extension portions 834 extend along the radial direction Dr and are lined up in the circumferential direction Dc.

[0132] The first connecting portion 836 extends from the first power supply portion 831 toward one side in the second direction (circumferential direction Dc) and is connected to a first portion 841a of the first extending portion 841. A second portion 841b of the first extending portion 841 is connected to a second curved portion 839 that follows the outer shape of the second power supply portion 832. The second connecting portion 837 extends from the second power supply portion 832 toward the other side in the second direction (circumferential direction Dc) and is connected to a fifth portion 842b of the second extending portion 842. A fourth portion 842a of the second extending portion 842 is connected to a first curved portion 838 that follows the outer shape of the first power supply portion 831.

[0133] In this example as well, the third distance L3 and the fourth distance L4 are each equal to or less than the first distance L1. Furthermore, the third distance L3 and the fourth distance L4 are each equal to or less than the second distance L2. In this example as well, by arranging the first power supply part 831 and the second power supply part 832 in positions close to each other and arranging the parts of the heater line 833 adjacent to the first power supply part 831 and the second power supply part 832 (the first extension part 841 and the second extension part 842) near the first power supply part 831 and the second power supply part 832, it is possible to improve the uniformity of the temperature distribution within the surface of the treatment object W while preventing temperature control from becoming complicated.

[0134] 11 to 14 are plan views each showing a schematic view of a part of the first zone of a heater portion according to a modified example of the embodiment. 11 to 14, the first direction is represented by D1, and the second direction is represented by D2. 11 to 14, only a part of the first zone 810 is shown, and the distance L2 is omitted. 11 to 14, the first connection portion 836 and the second connection portion 837 may be provided anywhere as long as they are not located between the first power supply portion 831 and the second power supply portion 832. The first connection portion 836 may extend, for example, to one side in the first direction (the side opposite to the second power supply portion 832), one side in the second direction, or the other side in the second direction. The second connection portion 837 may extend, for example, to the other side in the first direction (the side opposite to the first power supply portion 831), one side in the second direction, or the other side in the second direction. The second connection portion 837 may extend opposite to the first connection portion 836, may extend on the same side as the first connection portion 836, or may extend in a direction intersecting the direction in which the first connection portion 836 extends.

[0135] 11 , in this example, the first connection portion 836 extends from the first power supply portion 831 toward one side in the first direction. The first connection portion 836 is connected to a first portion 841a of the first extending portion 841 via a first curved portion 838 that follows the outer shape of the first power supply portion 831. The second connection portion 837 extends from the second power supply portion 832 toward the other side in the first direction. The second connection portion 837 is connected to a fifth portion 842b of the second extending portion 842 via a second curved portion 839 that follows the outer shape of the second power supply portion 832.

[0136] 12, in this example, first connection portion 836 extends from first power supply portion 831 toward the other side in the second direction. First connection portion 836 is connected to a first portion 841a of first extension portion 841 via a first curved portion 838 that follows the outer shape of first power supply portion 831. Second connection portion 837 extends from second power supply portion 832 toward one side in the second direction. Second connection portion 837 is connected to a fifth portion 842b of second extension portion 842 via a second curved portion 839 that follows the outer shape of second power supply portion 832.

[0137] 13, in this example, the first connection portion 836 extends from the first power supply portion 831 toward the other side in the second direction. The first connection portion 836 is connected to a first portion 841a of the first extending portion 841 via a first curved portion 838 that follows the outer shape of the first power supply portion 831. A second portion 841b of the first extending portion 841 is connected to a second curved portion 839 that follows the outer shape of the second power supply portion 832. The second connection portion 837 extends from the second power supply portion 832 toward the other side in the second direction. The second connection portion 837 is connected to a fifth portion 842b of the second extending portion 842.

[0138] 14, in this example, the first connection portion 836 extends from the first power supply portion 831 toward the other side in the second direction. The first connection portion 836 is connected to a fourth portion 842a of the second extending portion 842. The second connection portion 837 extends from the second power supply portion 832 toward the other side in the first direction. The second connection portion 837 is connected to a second portion 841b of the first extending portion 841 via a second curved portion 839 that follows the outer shape of the second power supply portion 832. The first portion 841a of the first extending portion 841 is connected to a first curved portion 838 that follows the outer shape of the first power supply portion 831.

[0139] In these examples as well, the third distance L3 and the fourth distance L4 are each equal to or less than the first distance L1. Furthermore, the third distance L3 and the fourth distance L4 are each equal to or less than the second distance L2. In these examples as well, by arranging the first power supply part 831 and the second power supply part 832 in positions close to each other and arranging the parts of the heater line 833 adjacent to the first power supply part 831 and the second power supply part 832 (the first extension part 841 and the second extension part 842) near the first power supply part 831 and the second power supply part 832, it is possible to improve the uniformity of the temperature distribution within the surface of the treatment object W while preventing temperature control from becoming complicated.

[0140] FIG. 15 is a plan view schematically showing the first zone of a conventional heater section. 15, a first zone 910 of a conventional heater unit includes a first power supply portion 931, a second power supply portion 932, and a heater line 933. The heater line 933 includes a plurality of extending portions 934, a folded portion 935, a first connecting portion 936, a second connecting portion 937, a first curved portion 938, and a second curved portion 939. The plurality of extending portions 934 include a first extending portion 941 and a second extending portion 942. The first extending portion 941 includes a first portion 941a, a second portion 941b, and a third portion 941c. The second extending portion 942 includes a fourth portion 942a, a fifth portion 942b, and a sixth portion 942c. The first power supply portion 931, the second power supply portion 932, the heater line 933, the extending portion 934, the folded portion 935, the first connecting portion 936, the second connecting portion 937, the first curved portion 938, the second curved portion 939, the first extending portion 941, the second extending portion 942, the first portion 941a, the second portion 941b, the third portion 941c, the fourth portion 942a, the fifth portion 942b, and the sixth portion 942c are respectively , first power supply portion 831, second power supply portion 832, heater line 833, extension portion 834, folded portion 835, first connection portion 836, second connection portion 837, first curved portion 838, second curved portion 839, first extension portion 841, second extension portion 842, first portion 841a, second portion 841b, third portion 841c, fourth portion 842a, fifth portion 842b, and sixth portion 842c.

[0141] The minimum distance in the first direction (circumferential direction Dc) between the first power supply portion 931 and the second power supply portion 932 is defined as a first distance L1. The minimum distance in the second direction (radial direction Dr) between the multiple extension portions 934 is defined as a second distance L2. The distance in the second direction (radial direction Dr) between the first imaginary tangent line VT1 and the first extension portion 941 is defined as a third distance L3. The distance in the second direction (radial direction Dr) between the second imaginary tangent line VT2 and the second extension portion 942 is defined as a fourth distance L4.

[0142] In the first zone 910 of the conventional heater unit, the third distance L3 and the fourth distance L4 are longer than the first distance L1. Also, in the first zone 910 of the conventional heater unit, the third distance L3 and the fourth distance L4 are longer than the second distance L2.

[0143] 16(a) and 16(b) are graphs showing the simulation results of the temperature distribution in the first zone of the heater section. FIG. 16(b) is an enlarged view of the area C1 shown in FIG. 16(a). Figures 16(a) and 16(b) show the simulation results of the temperature distribution on the wafer in samples 1 to 3 when the refrigerant temperature is fixed and a voltage is applied to the heater section (first heater element 231) including the first zone to generate heat. 16(a) and 16(b), the horizontal axis represents the circumferential distance [mm] from the midpoint of the arc AR connecting the centers of the first and second feeders, with "0" representing the midpoint, and the vertical axis represents the temperature on the wafer [°C] at that position. Both ends of the horizontal axis correspond to both ends of the first zone in the circumferential direction Dc.

[0144] 16(a) and 16(b), the simulation results for Sample 1 are shown by a solid line, the simulation results for Sample 2 by a dashed line, and the simulation results for Sample 3 by a dashed line. Sample 1 corresponds to the electrostatic chuck including the first zone 810 of the heater unit according to the first embodiment shown in FIG. 8. Sample 2 corresponds to the electrostatic chuck including the first zone 810 of the heater unit according to the second embodiment shown in FIG. 9. Sample 3 corresponds to the electrostatic chuck including the first zone 910 of the conventional heater unit shown in FIG. 15.

[0145] As shown in Figures 16(a) and 16(b), in samples 1 and 2 in which the first power supply section 831 and the second power supply section 832 are arranged in close proximity to each other and the portions of the heater line 833 adjacent to the first power supply section 831 and the second power supply section 832 (first extension section 841 and second extension section 842) are arranged near the first power supply section 831 and the second power supply section 832, the temperature drop around the first power supply section 831 and the second power supply section 832 is suppressed compared to sample 3 in which the portions of the heater line 833 adjacent to the first power supply section 931 and the second power supply section 932 (first extension section 941 and second extension section 942) are not arranged near the first power supply section 931 and the second power supply section 932.

[0146] Furthermore, the third distance L3 of Sample 2 is shorter than the third distance L3 of Sample 3. Therefore, in Sample 2, the temperature drop around the first power feeding portion 831 and the second power feeding portion 832 is further suppressed compared to Sample 1.

[0147] FIG. 17 is a plan view schematically illustrating the first zone of the heater unit according to the embodiment. 17, the first zone 810 has a central region 811 and an outer periphery region 812. The central region 811 is located in the center of the first zone 810 in a planar view. The outer periphery region 812 is located outside the central region 811 in a planar view. For example, when the first zone 810 is heated, the temperature of the central region 811 becomes higher than the temperature of the outer periphery region 812.

[0148] In this example, the first zone 810 is an area surrounded by an inner circumferential edge 821, an outer circumferential edge 822, a first side edge 823, and a second side edge 824. The inner circumferential edge 821 overlaps with an inner end of a heater line 833 that constitutes the first zone 810 in the radial direction Dr. The outer circumferential edge 822 overlaps with an outer end of a heater line 833 that constitutes the first zone 810 in the radial direction Dr. In this example, the inner circumferential edge 821 and the outer circumferential edge 822 are arc-shaped.

[0149] The first side edge 823 is located between one end of the inner circumferential edge 821 and one end of the outer circumferential edge 822. The first side edge 823 overlaps with one end of the heater line 833 that constitutes the first zone 810 in the circumferential direction Dc. The second side edge 824 is located between the other end of the inner circumferential edge 821 and the other end of the outer circumferential edge 822. The second side edge 824 overlaps with the other end of the heater line 833 that constitutes the first zone 810 in the circumferential direction Dc. In this example, the first side edge 823 and the second side edge 824 are linear.

[0150] The central region 811 includes, for example, a center 815 of the first zone 810. The center 815 is the intersection of a center line RL1 in the radial direction Dr between the inner circumferential end 821 and the outer circumferential end 822 and a center line CL1 in the circumferential direction Dc between the first side end 823 and the second side end 824.

[0151] The central region 811 is a region between a center line RL2 in the radial direction Dr between the inner circumferential end 821 and the center line RL1 and a center line RL3 in the radial direction Dr between the outer circumferential end 822 and the center line RL1, and between a center line CL2 in the circumferential direction Dc between the first side end 823 and the center line CL1 and a center line CL3 in the circumferential direction Dc between the second side end 824 and the center line CL1. In other words, the central region 811 is inside the region surrounded by the center lines RL2, RL3, CL2, and CL3.

[0152] The outer peripheral region 812 is a region located outside the center lines RL2, RL3, CL2, and CL3 (i.e., on the opposite side from the center 815). That is, the outer peripheral region 812 is located between the center line RL2 and the inner peripheral edge 821, between the center line RL3 and the outer peripheral edge 822, between the center line CL2 and the first side edge 823, and between the center line CL3 and the second side edge 824.

[0153] In this example, the first power supply part 831 and the second power supply part 832 are provided in the central region 811. Also, in this example, the heater line 833 is provided in both the central region 811 and the outer circumferential region 812. At least one of the first power supply part 831 and the second power supply part 832 may be provided in the outer circumferential region 812.

[0154] In this specification, the expression "the first power supply portion 831 is provided in the central region 811" means that at least a portion of the first power supply portion 831 overlaps with the central region 811 in the Z direction. In other words, even when the first power supply portion 831 is provided on the boundary between the central region 811 and the outer peripheral region 812, the first power supply portion 831 is considered to be provided in the central region 811. In other words, when the first power supply portion 831 does not overlap even a portion of the central region 811 in the Z direction, the first power supply portion 831 is considered to be provided in the outer peripheral region 812. The same applies to the second power supply portion 832 and the heater line 833.

[0155] When the first zone 810 is heated, the temperatures of the first power supply part 831 and the second power supply part 832 tend to be lower than the temperature of the heater line 833. Furthermore, the heat density of the outer peripheral region 812 of the first zone 810 tends to be lower than that of the central region 811. Therefore, when the first zone 810 is heated, the temperature of the outer peripheral region 812 tends to be lower than the temperature of the central region 811.

[0156] In contrast to this, by providing the first power supply part 831 and the second power supply part 832, which are likely to have a lower temperature than the heater line 833, in the central region 811, which is likely to have a higher temperature than the peripheral region 812, it is possible to improve the uniformity of the temperature distribution within the surface of the first zone 810. This makes it possible to improve the uniformity of the temperature distribution within the surface of the object W to be processed.

[0157] FIG. 18 is a plan view schematically illustrating a first zone of a heater portion according to a modified example of the embodiment. 18, in this example, the first zone 810 includes the outer circumferential edge 810e of the heater section 200. That is, in this example, the first zone 810 is located at the outermost periphery of the heater section 200. When the first zone 810 is one of the subzones 700, the outer circumferential edge 810e is the outer circumferential edge 231e of the first heater element 231. When the first zone 810 is one of the main zones 600, the outer circumferential edge 810e is the outer circumferential edge 232e of the second heater element 232.

[0158] The first zone 810 has an inner circumferential portion 851 and an outer circumferential portion 852. The inner circumferential portion 851 is a portion located inward in the radial direction Dr from a center line RL1 in the radial direction Dr. The outer circumferential portion 852 is a portion located outward in the radial direction Dr from the center line RL1 in the radial direction Dr. The outer circumferential portion 852 includes an outer peripheral edge 810e of the heater portion 200. The center line RL1 in the radial direction Dr passes through the center in the radial direction Dr between the inner circumferential end 821 and the outer circumferential end 822 of the first zone 810. In other words, the center line RL1 in the radial direction Dr divides the first zone 810 into two equal parts in the radial direction Dr.

[0159] In this example, the first power supply part 831 and the second power supply part 832 are provided in the inner peripheral part 851. Also, in this example, the heater line 833 is provided in both the inner peripheral part 851 and the outer peripheral part 852. At least one of the first power supply part 831 and the second power supply part 832 may be provided in the outer peripheral part 852.

[0160] In this specification, the expression "first power supply portion 831 is provided in inner circumferential portion 851" means that at least a portion of first power supply portion 831 overlaps with inner circumferential portion 851 in the Z direction. In other words, even when first power supply portion 831 is provided on the boundary between inner circumferential portion 851 and outer circumferential portion 852, first power supply portion 831 is considered to be provided in inner circumferential portion 851. In other words, when first power supply portion 831 does not overlap even a portion of inner circumferential portion 851 in the Z direction, first power supply portion 831 is considered to be provided in outer circumferential portion 852. The same applies to second power supply portion 832 and heater line 833.

[0161] The temperature of the outermost peripheral portion of the processing object W tends to be lower than that of the inner portion. In contrast, when the first zone 810 includes the outer peripheral edge 810e of the heater section 200 (i.e., in the first zone 810 located at the outermost peripheral portion of the heater section 200), the first power supply section 831 and the second power supply section 832, which tend to have a lower temperature than the heater line 833 when the heater section 200 is heated, are provided in the inner peripheral portion 851 of the first zone 810, thereby improving the uniformity of the temperature distribution within the surface of the processing object W.

[0162] As described above, according to the embodiment, an electrostatic chuck is provided that can improve the uniformity of the temperature distribution within the surface of the processing object while preventing temperature control from becoming complicated.

[0163] The above describes the embodiments of the present invention. However, the present invention is not limited to these descriptions. Design modifications made by a person skilled in the art to the above-described embodiments are also included within the scope of the present invention as long as they include the features of the present invention. For example, the shape, dimensions, materials, arrangement, installation form, etc. of each element of the electrostatic chuck are not limited to those exemplified and can be modified as appropriate. Furthermore, the elements of each of the above-described embodiments can be combined to the extent technically possible, and such combinations are also included within the scope of the present invention as long as they include the features of the present invention. [Explanation of symbols]

[0164] 10 Electrostatic chuck 100 Ceramic dielectric substrate 101 First main surface 102 Second main surface 111 Electrode layer (adsorption electrode) 113 Convex 115 Groove 200 heater section 210 1st support plate 211 sides 220 First insulating layer 231 First heater element 231a, 231b First and second sub-feeding units 231c Sub-heater line 231e Outer rim 232 Second heater element 232a, 232b First and second main power supply units 232c Main Heater Line 232e Outer edge 240 Second insulating layer 245 Third insulating layer 250 bypass layer 251, 251a~251j Bypass section 260 Fourth insulating layer 270 Second support plate 271 sides 273 holes 280, 280a~280j power supply terminal 300 base plate 301 Communication path 303 Bottom surface 321 Introductory path 600, 601-603 Main Zone 700, 701a-701f, 702a-702f subzones 701, 702 1st, 2nd area 810 Zone 1 810e outer edge 811 Central area 812 Outer area 815 center 821 Inner edge 822 Outer edge 823, 824 1st and 2nd side ends 831, 832 First and second power supply sections 833 Heater Line 834 Extension 835 Folded part 836, 837 First and second connection parts 838, 839 First and second curved sections 841, 842 1st and 2nd extension parts 841a~841c Parts 1~3 842a~842c Part 4~6 851 Inner circumference 852 Outer periphery 910 Zone 1 931, 932 First and second power supply sections 933 Heater Line 934 Extension 935 Folded part 936, 937 First and second connection parts 938, 939 First and second curved sections 941, 942 1st and 2nd extension parts 941a~941c Parts 1~3 942a~942c Part 4~6 AR arc CL1~CL3 center line CT1, CT2 center Dc circumferential direction Dr radial direction L1~L4 1st~4th distance LM1~LM3, LS1, LS2 Radial width RL1~RL3 Center line VT1, VT2 First and second virtual tangents W Processing object

Claims

1. a ceramic dielectric substrate having a first main surface on which an object to be processed is placed and a second main surface opposite to the first main surface; a base plate supporting the ceramic dielectric substrate; a heater portion for heating the ceramic dielectric substrate; Equipped with the heater section includes a first power supply section, a second power supply section adjacent to the first power supply section, and a heater line that is an electrode connecting the first power supply section and the second power supply section and generates heat when a current flows through the heater line; the heater line extends along a first direction and has a plurality of extending portions aligned in a second direction perpendicular to the first direction; the plurality of extending portions include a first extending portion adjacent to the first power supply portion and the second power supply portion on one side in the second direction, and a second extending portion adjacent to the first power supply portion and the second power supply portion on the other side in the second direction, the first extension portion has a first portion overlapping with the first power supply portion in the second direction, a second portion overlapping with the second power supply portion in the second direction, and a third portion positioned between the first portion and the second portion in the first direction and not overlapping with the first power supply portion or the second power supply portion in the second direction; the second extension portion has a fourth portion overlapping with the first power supply portion in the second direction, a fifth portion overlapping with the second power supply portion in the second direction, and a sixth portion located between the fourth portion and the fifth portion in the first direction and not overlapping with the first power supply portion or the second power supply portion in the second direction; a first distance is a minimum distance between the first power supply unit and the second power supply unit in the first direction; a minimum distance between the plurality of extension portions in the second direction is a second distance; a third distance is a distance in the second direction between a first virtual tangent line that is along the first direction and is tangent to the first power supply portion and the second power supply portion on the one side in the second direction, and the first extension portion; When a distance in the second direction between a second virtual tangent line that is tangent to the first power supply portion and the second power supply portion on the other side in the second direction along the first direction and the second extension portion is defined as a fourth distance, the third distance and the fourth distance are each equal to or less than the first distance, The electrostatic chuck, wherein the third distance and the fourth distance are each less than or equal to the second distance.

2. The heater section has a plurality of zones, the plurality of zones includes a first zone including the first power feeder, the second power feeder, and the heater line; When viewed along a Z direction perpendicular to the first main surface, the first zone has a central region located at the center of the first zone and a peripheral region located outside the central region, The electrostatic chuck according to claim 1 , wherein the first power supply portion and the second power supply portion are provided in the central region.

3. The heater section has a plurality of zones, the plurality of zones includes a first zone including the first power feeder, the second power feeder, and the heater line; the first zone includes an outer periphery of the heater portion, the first zone has an inner circumferential portion located radially inward of a radial center line that divides the first zone into two equal parts in the radial direction, and an outer circumferential portion located radially outward of the radial center line and including the outer circumferential edge, The electrostatic chuck according to claim 1 , wherein the first power supply portion and the second power supply portion are provided on the inner peripheral portion.

4. 4. The electrostatic chuck according to claim 1, wherein the first direction is a circumferential direction.

5. 4. The electrostatic chuck according to claim 1, wherein the first direction is a radial direction.

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