JP2018022873A - Electrostatic chuck - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reliable electrostatic chuck capable of withstanding thermal, electrical and mechanical loads.SOLUTION: An electrostatic chuck comprises: a ceramic dielectric substrate; a base plate which is positioned away from the ceramic dielectric substrate and supports the ceramic dielectric substrate; and a heater plate installed between the ceramic dielectric substrate and the base plate. The heater plate has: a first and a second support plates installed between the ceramic dielectric substrate and the base plate; a first and a second resin layers installed between the first and the second support plates; a resin section installed between the first and the second resin layers; a heater element which is installed between the first and the second resin layers, has a first electrically conductive section and produces heat when electric current flows therethrough; and a first space section defined by a first side edge section of the first electrically conduction section in an in-plane direction, the first resin layer, the second resin layer and the resin section.SELECTED DRAWING: Figure 1

Description

  Aspects of the invention generally relate to electrostatic chucks.

  In a plasma processing chamber that performs etching, CVD (Chemical Vapor Deposition), sputtering, ion implantation, ashing, and the like, an electrostatic chuck is used as means for adsorbing and holding a processing object such as a semiconductor wafer or a glass substrate. The electrostatic chuck applies electrostatic attraction power to a built-in electrode and attracts a substrate such as a silicon wafer by electrostatic force.

  In a substrate processing apparatus having an electrostatic chuck, wafer temperature control is required to improve yield and quality (for example, improve wafer processing accuracy). For example, two types of wafer temperature control are required for the electrostatic chuck. One is performance (temperature uniformity) that makes the temperature distribution in the wafer surface uniform. The other is the performance that allows the wafer to reach a predetermined temperature in a short time. For example, heating performance (heating rate) by a heater is required. The temperature increase rate is related to the tact time when the wafer is processed, and thus affects the throughput. Further, the electrostatic chuck may be required to have a performance (temperature controllability) that intentionally changes the temperature within the wafer surface.

  As a method for controlling the temperature of the wafer, a method using an electrostatic chuck incorporating a heater (heating element) or a cooling plate is known. Normally, temperature uniformity is in a trade-off relationship with temperature controllability. At the same time, in the electrostatic chuck, the reliability of the heater, particularly the withstand voltage characteristic, is required.

  In the wafer processing process, an RF (Radio Frequency) voltage (high frequency voltage) is applied. When an RF voltage is applied, a general heater generates heat under the influence of a high frequency. Then, the temperature of the wafer is affected. Moreover, when the RF voltage is applied, a leakage current flows to the equipment side. Therefore, a mechanism such as a filter is required on the equipment side.

In a process in a plasma etching apparatus or the like, a wafer is irradiated with plasma having various intensities and various distributions. In that case, it is required to control the temperature of the wafer to a temperature suitable for the process (temperature uniformity and temperature controllability). Further, in order to improve productivity, it is required that the temperature of the wafer reach a predetermined temperature in a short time. A rapid temperature change, heat input, and application of a high-frequency voltage generate thermal, electrical, and mechanical loads on the electrostatic chuck. The electrostatic chuck is required to have high reliability (especially withstand voltage and adhesion reliability) for these loads.
For example, attempts have been made to satisfy these requirements by controlling the temperature of a heater built in the electrostatic chuck. However, it has been difficult to satisfy these requirements simultaneously.

JP 2010-40644 A

  The present invention has been made based on the recognition of such a problem, and an object thereof is to provide a highly reliable electrostatic chuck that can withstand a thermal, electrical, and mechanical load.

  According to a first aspect of the present invention, there is provided a ceramic dielectric substrate on which an object to be processed is placed, a base plate provided at a position separated from the ceramic dielectric substrate in the stacking direction and supporting the ceramic dielectric substrate, and the ceramic dielectric A heater plate provided between a substrate and the base plate, wherein the heater plate is provided between the ceramic dielectric substrate and the base plate, and includes a first support plate including metal, and the first plate. A second support plate including a metal provided between the support plate and the base plate, a first resin layer provided between the first support plate and the second support plate, A second resin layer provided between the first resin layer and the second support plate; a resin portion provided between the first resin layer and the second resin layer; Before the first resin layer A first conductive portion provided between the second resin layer and a second conductive portion spaced from the first conductive portion in an in-plane direction perpendicular to the stacking direction; , A heater element that generates heat when a current flows, a first side end portion in the in-plane direction of the first conductive portion, the first resin layer, the second resin layer, and the resin And a first space portion partitioned by the first resin layer, wherein the first resin layer is disposed between the first conductive portion and the second conductive portion. And an electrostatic chuck that is in contact with the resin portion.

  According to this electrostatic chuck, the first space (gap) is provided at the end of the first conductive portion of the heater element. Even if the heater element is thermally expanded, the first conductive portion is deformed so as to fill the first space portion. For this reason, when a heater element deform | transforms by thermal expansion, the stress concerning a 1st resin layer and a 2nd resin layer can be reduced. Therefore, peeling between the heater element and the first resin layer and peeling between the heater element and the second resin layer can be suppressed. Therefore, the resistance to the load is high and the reliability can be improved. It is possible to suppress the temperature change of the processing object caused by the peeling.

  In a second aspect based on the first aspect, the first conductive portion has a second side end portion that is spaced apart from the first side end portion in the in-plane direction, and the heater plate includes: An electrostatic chuck comprising at least a second space defined by the second side end, the first resin layer, and the second resin layer.

  According to this electrostatic chuck, the second space (gap) is provided at the end of the first conductive portion of the heater element. Even if the heater element is thermally expanded, the first conductive portion is deformed so as to fill the second space portion. For this reason, when a heater element deform | transforms by thermal expansion, the stress concerning a 1st resin layer and a 2nd resin layer can be reduced. Therefore, peeling between the heater element and the first resin layer and peeling between the heater element and the second resin layer can be suppressed. It is possible to suppress the temperature change of the processing object caused by the peeling.

  According to a third invention, in the first or second invention, a length of the first space portion along the stacking direction is equal to or shorter than a length of the first conductive portion along the stacking direction. This is an electrostatic chuck.

  According to this electrostatic chuck, even if the heater element is deformed by thermal expansion, the space is filled, so that the stress applied to the first resin layer and the second resin layer can be reduced. Therefore, peeling between the heater element and the first resin layer and peeling between the heater element and the second resin layer can be suppressed. It is possible to suppress the temperature change of the processing object caused by the peeling.

  According to a fourth invention, in any one of the first to third inventions, the first resin layer is separated from the second resin layer between the first conductive portion and the resin portion. This is an electrostatic chuck.

  According to this electrostatic chuck, the space between the first resin layer and the second resin layer does not become too narrow (there is no minimum portion). Thereby, when a heater element deform | transforms, the stress concerning a 1st resin layer and a 2nd resin layer is easy to reduce.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the shape of the first space portion has four vertices in a cross section parallel to the stacking direction. It is an electric chuck.

  According to this electrostatic chuck, the space between the first resin layer and the second resin layer does not become too narrow (there is no minimum portion). Thereby, when a heater element deform | transforms, the stress concerning a 1st resin layer and a 2nd resin layer is easy to reduce.

  A sixth invention is the electrostatic chuck according to any one of the first to fifth inventions, wherein the first support plate is electrically joined to the second support plate.

  According to this electrostatic chuck, the heater element can be shielded from high frequency. Thereby, it can suppress that a heater element generates heat to abnormal temperature. Moreover, the impedance of the heater plate can be suppressed.

  In a seventh aspect based on any one of the first to sixth aspects, the area of the region where the first support plate is joined to the second support plate is the area of the upper surface of the first support plate. The electrostatic chuck is narrower than that of the lower surface of the second support plate.

  According to this electrostatic chuck, the heater element can be shielded from high frequency. Thereby, it can suppress that a heater element generates heat to abnormal temperature. Moreover, the impedance of the heater plate can be suppressed.

  An eighth invention is the electrostatic chuck according to any one of the first to seventh inventions, wherein the resin portion includes a material different from a material of the first resin layer.

  According to this electrostatic chuck, the heat conduction and heat capacity in the heater plate can be controlled by the resin portion. Thereby, both soaking property and thermal conductivity can be achieved.

  A ninth invention is the electrostatic chuck according to any one of the first to eighth inventions, wherein the thickness of the first resin layer is equal to or less than the thickness of the first conductive portion.

  According to this electrostatic chuck, the first resin layer can be prevented from separating from the first conductive portion at the upper portion of the first conductive portion. Since the heater element and the resin layer can be adhered to each other, it is possible to achieve the thermal uniformity and withstand voltage characteristics as designed. Moreover, since the unevenness | corrugation is formed in the upper surface of a 1st support plate by ensuring the adhesiveness of a heater element and a resin layer, the distance between a heater element and a process target object can be shortened. Thereby, the speed which raises the temperature of a process target object can be improved. Therefore, it is possible to achieve both “heating performance (heating rate) of the heater”, “temperature uniformity”, and “withstand voltage reliability”.

  According to a tenth aspect, in any one of the first to ninth aspects, the first space portion includes a central portion in the in-plane direction and an end portion in the in-plane direction, and the central portion The electrostatic chuck is characterized in that a width along the laminating direction is narrower than a width along the laminating direction of the end portion.

  According to this electrostatic chuck, when the heater element is deformed by thermal expansion, the stress applied to the first resin layer and the second resin layer can be more easily relaxed.

  In an eleventh aspect based on any one of the first to tenth aspects, the length of the upper surface of the first conductive portion along the in-plane direction is equal to the in-plane length of the lower surface of the first conductive portion. The electrostatic chuck is characterized by being different in length along the direction.

  According to this electrostatic chuck, the stress applied to the first resin layer and the second resin layer when the heater element is deformed by thermal expansion can be reduced. Therefore, peeling between the heater element and the first resin layer and peeling between the heater element and the second resin layer can be suppressed. It is possible to suppress the temperature change of the processing object caused by the peeling.

  In a twelfth aspect based on the eleventh aspect, the length along the in-plane direction of the lower surface of the first conductive portion is equal to the length along the in-plane direction of the upper surface of the first conductive portion. It is an electrostatic chuck characterized by being longer than the length.

  The temperature below the heater element is lower than the temperature above the heater element, and the heat distribution may be biased in the vertical direction. According to this electrostatic chuck, it is possible to suppress such an uneven distribution of heat in the vertical direction.

  In a thirteenth aspect based on the eleventh aspect, the length along the in-plane direction of the upper surface of the first conductive portion is equal to the length along the in-plane direction of the lower surface of the first conductive portion. It is an electrostatic chuck characterized by being longer than the length.

  According to this electrostatic chuck, since the upper surface of the heater element is long, the upper part of the heater element on which the object to be processed is arranged can be easily heated. Further, since the lower surface of the heater element is relatively short, the lower portion of the heater element can be easily cooled. Thereby, temperature followability (ramp plate) can be improved.

  According to a fourteenth aspect of the invention, in any one of the first to thirteenth aspects, the side surface of the first conductive portion is curved in a cross section parallel to the stacking direction. It is a chuck.

  According to this electrostatic chuck, since the side surface is a curved surface, it is possible to more easily suppress the stress applied to the first resin layer and the second resin layer when the heater element is deformed.

  According to a fifteenth aspect, in any one of the first to fourteenth aspects, an angle between the upper surface of the first conductive portion and the side surface of the first conductive portion is a lower surface of the first conductive portion. And an angle between the side surface and the side surface.

  According to this electrostatic chuck, it is possible to achieve both the reduction of the peeling of the resin layer adjacent to the heater element due to the relaxation of the stress on the resin layer due to the deformation of the heater due to thermal expansion, and the thermal characteristics such as heat uniformity and temperature followability. it can.

  According to a sixteenth aspect, in any one of the first to fifteenth aspects, the side surface of the first conductive portion is at least one of the upper surface of the first conductive portion and the lower surface of the first conductive portion. Is an electrostatic chuck characterized by being rough.

  According to this electrostatic chuck, since the side surface is rougher than at least one of the upper surface and the lower surface of the conductive portion, thermal diffusion from the side surface is improved, and thermal characteristics such as heat uniformity and temperature followability can be improved. .

  According to a seventeenth aspect, in any one of the first to sixteenth aspects, the heater element has a belt-like heater electrode, and the heater electrode is provided in a plurality of regions in an independent state. This is an electrostatic chuck.

  According to this electrostatic chuck, since the heater electrodes are provided in a plurality of regions independently of each other, the in-plane temperature of the processing object can be controlled independently for each region. Thereby, it is possible to intentionally make a difference in the in-plane temperature of the processing object.

  According to an eighteenth aspect of the present invention, in any one of the first to seventeenth aspects, the plurality of heater elements are provided, and the plurality of heater elements are provided in different states from each other. Electrostatic chuck.

  According to this electrostatic chuck, since the heater elements are provided in different states in different layers, the temperature within the surface of the processing object can be controlled independently for each region. Thereby, it is possible to intentionally make a difference in the in-plane temperature of the processing object (temperature controllability).

  According to a nineteenth aspect of the present invention, in any one of the first to eighteenth aspects, the first support plate includes a first support portion aligned with the first conductive portion in the stacking direction, and the first support plate in the stacking direction. A second support portion aligned with the first space portion, and the second support plate includes a third support portion aligned with the first conductive portion in the stacking direction, and the second support plate in the stacking direction. A fourth support part aligned with the one space part, and a distance between the second support part and the fourth support part is determined between the first support part and the third support part. It is an electrostatic chuck characterized by being shorter than the distance between.

  According to this electrostatic chuck, irregularities are formed on at least one of the first support plate and the second support plate. Such unevenness is formed by high adhesion between the heater element (first conductive portion) and a member sandwiching the heater element. Due to the high adhesion, it is possible to achieve the thermal uniformity and withstand voltage characteristics as designed. Moreover, the distance between a heater element and a process target object can be shortened by forming a convex part in the 1st support plate. Thereby, the speed which raises the temperature of a process target object can be improved. Therefore, it is possible to achieve both “heating performance (heating rate) of the heater”, “temperature uniformity”, and “withstand voltage reliability”.

  According to a twentieth aspect of the invention, in any one of the first to eighteenth aspects, the first support plate includes: a first support portion aligned with the first conductive portion in the stacking direction; and the first support plate in the stacking direction. A second support portion aligned with the first space portion, and the second support plate includes a third support portion aligned with the first conductive portion in the stacking direction, and the second support plate in the stacking direction. A fourth support part aligned with the one space part, and a distance between the second support part and the fourth support part is determined between the first support part and the third support part. An electrostatic chuck characterized by being substantially the same as the distance between.

According to this electrostatic chuck, unevenness is not formed on the first support plate and the second support plate, or the unevenness is very small. The first support plate and the second support plate are, for example, flat. As a result, variations in the thickness of the adhesive that joins the heater plate, the ceramic dielectric substrate, and the base plate can be reduced, and in-plane heat transfer can be made uniform.
Further, the distance between the heater element and the object to be processed is reduced over the entire surface, and the speed at which the temperature of the object to be processed is increased can be improved. Therefore, it is possible to achieve both “heater heating performance (temperature increase rate)” and “temperature uniformity”.

  According to a twenty-first aspect, in any one of the first to twentieth aspects, the present invention further includes a conductive bypass layer provided between the heater element and the second support plate. Electrostatic chuck.

  According to this electrostatic chuck, a greater degree of freedom can be given to the arrangement of terminals for supplying power to the heater element. By providing the bypass layer, it is not necessary to directly join the terminal having a large heat capacity to the heater element as compared with the case where the bypass layer is not provided. Thereby, the uniformity of the temperature distribution in the surface of a process target object can be improved. Moreover, it is not necessary to join a terminal to a thin heater element compared with the case where a bypass layer is not provided. Thereby, the reliability of a heater plate can be improved.

  In a twenty-second aspect based on the twenty-first aspect, the relationship of the width of the lower surface of the bypass layer with respect to the width of the upper surface of the bypass layer is that of the first conductive portion with respect to the width of the upper surface of the first conductive portion. An electrostatic chuck characterized by having the same size relationship as the width of the lower surface.

  According to this electrostatic chuck, when the upper surface is wider than the lower surface in each of the bypass layer and the heater element (first conductive portion), the upper portion of the heater plate can be easily heated. Further, since the lower surface is relatively short, the lower part of the heater plate can be easily cooled. Thereby, temperature followability (ramp plate) can be improved. In each of the bypass layer and the first conductive portion, when the lower surface is wider than the upper surface, it is possible to suppress the deviation of the heat distribution in the vertical direction.

  In a twenty-third aspect based on the twenty-first aspect, the relationship of the width of the lower surface of the bypass layer with respect to the width of the upper surface of the bypass layer is that of the first conductive portion with respect to the width of the upper surface of the first conductive portion. An electrostatic chuck characterized by being opposite to the magnitude relation of the width of the lower surface.

  According to this electrostatic chuck, the direction of the stress applied by the thermal expansion of the bypass layer can be made opposite to the direction of the stress applied by the thermal expansion of the heater element. Thereby, the influence of stress can be suppressed more.

  In a twenty-fourth aspect based on any one of the twenty-first to twenty-third aspects, the heater element is electrically connected to the bypass layer, and the heater element and the bypass layer include the first support plate and the The electrostatic chuck is insulated from the second support plate.

  According to this electrostatic chuck, electric power can be supplied to the heater element from the outside via the bypass layer.

  According to a twenty-fifth aspect of the invention, in any one of the first to twenty-fourth aspects, the area of the upper surface of the first support plate is larger than the area of the lower surface of the second support plate. It is a chuck.

  According to this electrostatic chuck, a terminal for supplying power to the heater element can be more easily connected on the second support plate side as viewed from the heater element.

  According to a twenty-sixth aspect of the present invention, in any one of the first to twenty-fifth aspects, the static electricity generator further includes a power supply terminal that is provided from the heater plate toward the base plate and supplies electric power to the heater plate. It is an electric chuck.

  According to the electrostatic chuck, since the power supply terminal is provided from the heater plate toward the base plate, power can be supplied to the power supply terminal from a lower surface side of the base plate via a member called a socket. Thereby, the wiring of the heater is realized while suppressing the supply terminal from being exposed in the chamber in which the electrostatic chuck is installed.

  In a twenty-seventh aspect based on the twenty-sixth aspect, the power supply terminal includes a pin portion connected to a socket for supplying electric power from the outside, a conductor portion thinner than the pin portion, and a support connected to the conductor portion. An electrostatic chuck comprising: a portion; and a joint portion connected to the support portion and joined to the heater element.

  According to this electrostatic chuck, since the pin portion is thicker than the conducting wire portion, the pin portion can supply a relatively large current to the heater element. Moreover, since the conducting wire portion is thinner than the pin portion, the conducting wire portion is more easily deformed than the pin portion, and the position of the pin portion can be shifted from the center of the joint portion. Thereby, a power feeding terminal can be fixed to a member (for example, a base plate) different from the heater plate. For example, when the support portion is joined to the lead wire portion and the joint portion by welding, joining using laser light, soldering, brazing, etc., the stress applied to the power supply terminal is reduced while the heater element is relaxed. A wider contact area can be ensured.

  A twenty-eighth aspect of the present invention is the electronic device according to any one of the twenty-first to twenty-fourth aspects, further comprising a power feeding terminal that is provided from the heater plate toward the base plate and that supplies power to the heater plate. A pin portion connected to a socket for supplying power from, a conductive wire portion thinner than the pin portion, a support portion connected to the conductive wire portion, and a joint portion connected to the support portion and bonded to the bypass layer The electrostatic chuck is configured to supply the electric power to the heater element through the bypass layer.

  According to this electrostatic chuck, since the pin portion is thicker than the conducting wire portion, the pin portion can supply a relatively large current to the heater element. Moreover, since the conducting wire portion is thinner than the pin portion, the conducting wire portion is more easily deformed than the pin portion, and the position of the pin portion can be shifted from the center of the joint portion. Thereby, a power feeding terminal can be fixed to a member (for example, a base plate) different from the heater plate. For example, when the support portion is joined to the lead wire portion and the joint portion by welding, joining using laser light, soldering, brazing, or the like, the stress applied to the power supply terminal is reduced while the stress is applied to the bypass layer. A wider contact area can be ensured. In addition, when the support portion is joined to the lead wire portion and the joint portion by, for example, welding, joining using laser light, soldering, brazing, etc., the joint portion having substantially the same thickness as the heater plate and the bypass layer Can be provided.

  According to a twenty-ninth aspect of the invention, in any one of the first to twenty-fifth aspects, the power supply terminal further includes a power supply terminal that is provided on the base plate and supplies power to the heater plate, and the power supply terminal supplies power from the outside. An electrostatic chuck comprising: a power supply unit connected to a socket; and a terminal unit connected to the power supply unit and pressed against the heater plate.

  According to this electrostatic chuck, the diameter of the hole provided for power feeding can be made smaller than when the power feeding terminals are joined by welding or the like.

  According to an aspect of the present invention, a highly reliable electrostatic chuck is provided.

It is a typical perspective view showing the electrostatic chuck concerning this embodiment. FIG. 2A and FIG. 2B are schematic cross-sectional views showing the electrostatic chuck according to the present embodiment. It is a typical perspective view showing the heater plate of this embodiment. FIG. 4A and FIG. 4B are schematic perspective views showing the heater plate of the present embodiment. It is a typical exploded view showing the heater plate of this embodiment. It is sectional drawing showing a part of heater plate of this embodiment. It is a photographic image of the heater plate of this embodiment. It is sectional drawing showing a part of heater plate of this embodiment. It is sectional drawing showing a part of heater plate of this embodiment. It is sectional drawing showing a part of another heater plate of this embodiment. FIG. 11A and FIG. 11B are cross-sectional views showing a part of a modified example of the heater plate of the present embodiment. 12A and 12B are cross-sectional views showing a part of a modification of the heater plate of the present embodiment. FIG. 13A and FIG. 13B are cross-sectional views showing a part of a modified example of the heater plate of the present embodiment. FIG. 14A to FIG. 14D are cross-sectional views showing a part of a modified example of the heater plate of the present embodiment. It is a typical exploded view showing the modification of the heater plate of this embodiment. FIG. 16A and FIG. 16B are schematic cross-sectional views illustrating an example of the manufacturing method of this embodiment. It is typical sectional drawing which illustrates another example of the manufacturing method of this embodiment. It is a typical exploded view showing the electrostatic chuck concerning this embodiment. FIG. 19A and FIG. 19B are electric circuit diagrams showing an electrostatic chuck. FIG. 20A and FIG. 20B are schematic plan views showing specific examples of the heater plate of the present embodiment. FIG. 21A and FIG. 21B are schematic plan views illustrating the heater element of this example. It is a typical top view which illustrates the heater element of this example. FIG. 23A and FIG. 23B are schematic plan views illustrating the bypass layer of this example. FIG. 24A and FIG. 24B are enlarged views schematically showing a part of the heater plate of this specific example. FIG. 25A and FIG. 25B are schematic views for explaining the shape of the surface of the heater plate of the present embodiment. FIG. 26A and FIG. 26B are schematic cross-sectional views showing an electrostatic chuck according to a modification of the present embodiment. FIG. 27A and FIG. 27B are schematic plan views showing a modification of the first support plate of the present embodiment. It is a typical top view showing the modification of the 1st support plate of this embodiment. It is typical sectional drawing showing the heater plate of this modification. FIG. 30A to FIG. 30D are cross-sectional views showing a part of a modified example of the heater plate of the present embodiment. Fig.31 (a)-FIG.31 (d) is sectional drawing showing a part of modification of the heater plate of this embodiment. FIG. 32A to FIG. 32D are cross-sectional views showing a part of a modified example of the heater plate of the present embodiment. FIG. 33A to FIG. 33D are cross-sectional views showing a part of a modification of the heater plate of the present embodiment. FIG. 34A and FIG. 34B are explanatory diagrams illustrating an example of a simulation result of the heater plate. FIG. 35A and FIG. 35B are schematic plan views illustrating specific examples of the power supply terminal of the present embodiment. It is a typical exploded view showing the modification of the heater plate of this embodiment. It is typical sectional drawing showing the modification of the electric power feeding terminal of this embodiment. It is typical sectional drawing showing the wafer processing apparatus concerning other embodiment of this invention. It is typical sectional drawing showing the modification of the wafer processing apparatus concerning other embodiment of this invention. It is typical sectional drawing showing the modification of the wafer processing apparatus concerning other embodiment of this invention.

Embodiments of the present invention will be described below with reference to the drawings. In addition, in each drawing, the same code | symbol is attached | subjected to the same component and detailed description is abbreviate | omitted suitably.
FIG. 1 is a schematic perspective view showing an electrostatic chuck according to the present embodiment.
FIG. 2A and FIG. 2B are schematic cross-sectional views showing the electrostatic chuck according to the present embodiment.
For convenience of explanation, FIG. 1 shows a cross-sectional view of a part of the electrostatic chuck. FIG. 2A is a schematic cross-sectional view taken along the cut plane A1-A1 illustrated in FIG. 1, for example. FIG. 2B is a schematic enlarged view of the region B1 shown in FIG.

The electrostatic chuck 10 according to the present embodiment includes a ceramic dielectric substrate 100, a heater plate 200, and a base plate 300.
The ceramic dielectric substrate 100 is provided at a position away from the base plate 300 in the stacking direction (Z direction). The heater plate 200 is provided between the base plate 300 and the ceramic dielectric substrate 100.

  An adhesive 403 is provided between the base plate 300 and the heater plate 200. An adhesive 403 is provided between the heater plate 200 and the ceramic dielectric substrate 100. Examples of the material of the adhesive 403 include heat-resistant resins such as silicone having relatively high thermal conductivity. The thickness of the adhesive 403 is, for example, about 0.1 millimeter (mm) or more and 1.0 mm or less. The thickness of the adhesive 403 is the same as the distance between the base plate 300 and the heater plate 200 or the distance between the heater plate 200 and the ceramic dielectric substrate 100.

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

  Here, in the description of the present embodiment, the direction connecting the first main surface 101 and the second main surface 102 is the Z direction, and one of the directions orthogonal to the Z direction is orthogonal to the X direction, the Z direction, and the X direction. The direction to do is referred to as the Y direction. The Z direction is substantially parallel to the stacking direction of the base plate 300, the heater plate 200, and the ceramic dielectric substrate 100. For example, the Z direction is substantially perpendicular to the first major surface 101 or the second major surface 102. In the description of the present embodiment, the in-plane direction is one direction parallel to a plane including the X direction and the Y direction.

Examples of the crystal material included in the ceramic dielectric substrate 100 include Al ₂ O ₃ , Y ₂ O _3, and YAG. By using such a material, infrared transmittance, insulation resistance, and plasma durability in the ceramic dielectric substrate 100 can be enhanced.

  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. That is, the electrode layer 111 is formed so as to be inserted into the ceramic dielectric substrate 100. The electrode layer 111 is integrally sintered with the ceramic dielectric substrate 100.

  The electrode layer 111 is not limited to be interposed between the first main surface 101 and the second main surface 102, and may be attached to the second main surface 102.

  The electrostatic chuck 10 generates an electric charge on the first main surface 101 side of the electrode layer 111 by applying an adsorption holding voltage to the electrode layer 111, and adsorbs and holds the processing object W by electrostatic force.

  The heater plate 200 generates heat when the heater current flows, and the temperature of the processing object W can be increased as compared with the case where the heater plate 200 does not generate heat.

  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 object W. The electrode layer 111 may be monopolar or bipolar. The electrode layer 111 may be a tripolar type or other multipolar type. The number of the electrode layers 111 and the arrangement of the electrode layers 111 are appropriately selected.

  The ceramic dielectric substrate 100 includes a first dielectric layer 107 between the electrode layer 111 and the first major surface 101, and a second dielectric layer 109 between the electrode layer 111 and the second major surface 102. The infrared spectral transmittance of at least the first dielectric layer 107 of the ceramic dielectric substrate 100 is preferably 20% or more. In the present embodiment, the infrared spectral transmittance is a value in terms of a thickness of 1 mm.

  Since the infrared spectral transmittance of at least the first dielectric layer 107 of the ceramic dielectric substrate 100 is 20% or more, infrared rays emitted from the heater plate 200 in a state where the processing object W is placed on the first main surface 101. Can efficiently pass through the ceramic dielectric substrate 100. Therefore, it becomes difficult for heat to accumulate in the processing object W, and the controllability of the temperature of the processing object W is improved.

  For example, when the electrostatic chuck 10 is used in a chamber in which plasma processing is performed, the temperature of the processing target W is likely to increase as the plasma power increases. In the electrostatic chuck 10 of the present embodiment, the heat transmitted to the processing object W by the plasma power is efficiently transmitted to the ceramic dielectric substrate 100. Further, the heat transmitted to the ceramic dielectric substrate 100 by the heater plate 200 is efficiently transmitted to the processing object W. Therefore, heat is efficiently transmitted and it becomes easy to maintain the processing target W at a desired temperature.

  In the electrostatic chuck 10 according to this embodiment, it is desirable that the infrared spectral transmittance of the second dielectric layer 109 in addition to the first dielectric layer 107 is 20% or more. Since the infrared spectral transmittance of the first dielectric layer 107 and the second dielectric layer 109 is 20% or more, the infrared rays emitted from the heater plate 200 are more efficiently transmitted through the ceramic dielectric substrate 100, and are to be processed. The temperature controllability of the object W can be improved.

  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 via the heater plate 200. A communication path 301 is provided in the base plate 300. That is, the communication path 301 is provided inside the base plate 300. An example of the material of the base plate 300 is aluminum.

  The base plate 300 serves to adjust the temperature of the ceramic dielectric substrate 100. For example, when the ceramic dielectric substrate 100 is cooled, a cooling medium is introduced into the communication path 301. The inflowing cooling medium passes through the communication path 301 and flows out of the communication path 301. Thereby, the heat of the base plate 300 can be absorbed by the cooling medium, and the ceramic dielectric substrate 100 mounted thereon can be cooled.

  On the other hand, when the ceramic dielectric substrate 100 is heated, it is possible to put a heating medium in the communication path 301. Alternatively, a heater (not shown) can be built in the base plate 300. As described above, when the temperature of the ceramic dielectric substrate 100 is adjusted by the base plate 300, the temperature of the processing object W attracted and held by the electrostatic chuck 10 can be easily adjusted.

  Further, a convex portion 113 is provided on the first main surface 101 side of the ceramic dielectric substrate 100 as necessary. A groove 115 is provided between the convex portions 113 adjacent to each other. The grooves 115 communicate with each other. A space is formed between the back surface of the processing object W mounted on the electrostatic chuck 10 and the groove 115.

  An introduction path 321 that penetrates the base plate 300 and the ceramic dielectric substrate 100 is connected to the groove 115. When a transmission gas such as helium (He) is introduced from the introduction path 321 with the processing object W adsorbed and held, the transmission gas flows into a 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.

FIG. 3 is a schematic perspective view showing the heater plate of the present embodiment.
FIG. 4A and FIG. 4B are schematic perspective views showing the heater plate of the present embodiment.
FIG. 5 is a schematic exploded view showing the heater plate of the present embodiment.
FIG. 3 is a schematic perspective view of the heater plate according to the present embodiment as viewed from the upper surface (the surface on the ceramic dielectric substrate 100 side). FIG. 4A is a schematic perspective view of the heater plate according to the present embodiment as viewed from the lower surface (the surface on the base plate 300 side). FIG. 4B is a schematic enlarged view of the region B2 shown in FIG.

  As shown in FIG. 5, the heater plate 200 of the present embodiment includes a first support plate 210, a first resin layer 220, a heater element (heat generation layer) 230, a second resin layer 240, A second support plate 270 and a power supply terminal 280 are provided. In addition, the heater plate 200 has a resin portion 223 described later (see FIG. 6). As shown in FIG. 3, the surface 211 (upper surface) of the first support plate 210 forms the upper surface of the heater plate 200. As shown in FIG. 4, the surface 271 (lower surface) of the second support plate 270 forms the lower surface of the heater plate 200. The first support plate 210 and the second support plate 270 are support plates that support the heater element 230 and the like. In this example, the first support plate 210 and the second support plate 270 sandwich the first resin layer 220, the heater element 230, and the second resin layer 240 and support them.

  The first support plate 210 is provided between the ceramic dielectric substrate 100 and the base plate 300. The second support plate 270 is provided between the first support plate 210 and the base plate 300. The first resin layer 220 is provided between the first support plate 210 and the second support plate 270. The second resin layer 240 is provided between the first resin layer 220 and the second support plate 270. The heater element 230 is provided between the first resin layer 220 and the second resin layer 240.

  The first support plate 210 has a relatively high thermal conductivity. Examples of the material of the first support plate 210 include a metal containing at least one of aluminum, copper, and nickel, and graphite having a multilayer structure. From the viewpoint of achieving both “in-plane temperature uniformity of the object to be processed” and “high throughput”, which are generally contradictory, and from the viewpoint of contamination and magnetism of the chamber, Aluminum or aluminum alloy is suitable. The thickness (length in the Z direction) of the first support plate 210 is, for example, about 0.1 mm or more and 5.0 mm or less. More preferably, the thickness of the first support plate 210 is, for example, about 0.3 mm or more and 1.0 mm or less. The first support plate 210 improves the uniformity of the temperature distribution in the surface of the heater plate 200. The first support plate 210 suppresses the warp of the heater plate 200. The first support plate 210 improves the strength of adhesion between the heater plate 200 and the ceramic dielectric substrate 100.

In the processing process of the processing object W, RF (Radio Frequency) voltage (high frequency voltage) is applied. When the high frequency voltage is applied, the heater element 230 may generate heat under the influence of the high frequency. As a result, the temperature controllability of the heater element 230 decreases.
In contrast, in the present embodiment, the first support plate 210 blocks the heater element 230 and the bypass layer 250 from high frequencies. Thereby, the first support plate 210 can suppress the heater element 230 from generating heat to an abnormal temperature.

  The material, thickness, and function of the second support plate 270 can be freely set according to required performance, dimensions, and the like. For example, the material, thickness, and function of the second support plate 270 may be the same as the material, thickness, and function of the first support plate 210, respectively. The first support plate 210 is electrically joined to the second support plate 270. Here, contact is included in the range of “joining” in the present specification. The details of the electrical connection between the second support plate 270 and the first support plate 210 will be described later.

  Thus, the first support plate 210 and the second support plate 270 have a relatively high thermal conductivity. Thereby, the first support plate 210 and the second support plate 270 improve the thermal diffusibility of the heat supplied from the heater element 230. Moreover, the 1st support plate 210 and the 2nd support plate 270 suppress the curvature of the heater plate 200, for example by having moderate thickness and rigidity. Furthermore, the first support plate 210 and the second support plate 270 improve the shielding performance against an RF voltage applied to, for example, an electrode of a wafer processing apparatus. For example, the influence of the RF voltage on the heater element 230 is suppressed. Thus, the first support plate 210 and the second support plate 270 have a function of thermal diffusion, a function of suppressing warpage, and a function of a shield against RF voltage.

  Examples of the material of the first resin layer 220 include polyimide and polyamideimide. The thickness (length in the Z direction) of the first resin layer 220 is about 20 μm or more and 0.20 mm or less, for example, 50 μm. The first resin layer 220 joins the first support plate 210 and the heater element 230 to each other. The first resin layer 220 electrically insulates between the first support plate 210 and the heater element 230. As described above, the first resin layer 220 has a function of electrical insulation and a function of surface bonding.

  The material and thickness of the second resin layer 240 are approximately the same as the material and thickness of the first resin layer 220, respectively.

  The second resin layer 240 joins the heater element 230 and the second support plate 270 to each other. The second resin layer 240 electrically insulates between the heater element 230 and the second support plate 270. As described above, the second resin layer 240 has a function of electrical insulation and a function of surface bonding.

  Examples of the material of the heater element 230 include metals including at least one of stainless steel, titanium, chromium, nickel, copper, and aluminum. The thickness (length in the Z direction) of the heater element 230 is about 10 μm or more and 0.20 mm or less, for example, 30 μm. The heater element 230 is electrically insulated from the first support plate 210 and the second support plate 270.

  The heater element 230 generates heat when current flows, and controls the temperature of the processing target W. For example, the heater element 230 heats the processing object W to a predetermined temperature. For example, the heater element 230 makes the temperature distribution in the surface of the processing object W uniform. For example, the heater element 230 intentionally makes a difference in the in-plane temperature of the processing object W. The heater element 230 has a belt-like heater electrode 239.

  The power supply terminal 280 is electrically joined to the heater element 230. In a state where the heater plate 200 is provided between the base plate 300 and the ceramic dielectric substrate 100, the power supply terminal 280 is provided from the heater plate 200 toward the base plate 300. The power supply terminal 280 supplies power supplied from the outside of the electrostatic chuck 10 to the heater element 230.

  The heater plate 200 has a plurality of power supply terminals 280. The heater plate 200 shown in FIGS. 3 to 5 has eight power supply terminals 280. The number of power supply terminals 280 is not limited to “8”. One power supply terminal 280 is electrically joined to one heater electrode 239. The hole 273 passes through the second support plate 270. The power supply terminal 280 is electrically joined to the heater electrode 239 through the hole 273.

  When electric power is supplied from the outside of the electrostatic chuck 10 to the power supply terminal 280 as indicated by the arrows Ca and Cb shown in FIG. 5, the current flows through the heater element 230 as indicated by the arrow Cc shown in FIG. It flows through a predetermined zone (area). Details of the zone of the heater element 230 will be described later. The current flowing to the heater element 230 flows to the power supply terminal 280 and flows from the power supply terminal 280 to the outside of the electrostatic chuck 10 as indicated by arrows Ca and Cb shown in FIG.

  As described above, the junction between the heater element 230 and the power supply terminal 280 includes a portion where the current enters the heater element 230 and a portion where the current exits from the heater element 230. That is, a pair exists at the joint between the heater element 230 and the power supply terminal 280. Since the heater plate 200 shown in FIGS. 3 to 5 has eight power supply terminals 280, there are four pairs at the joint between the heater element 230 and the power supply terminal 280.

  According to the present embodiment, the heater element 230 is provided between the first support plate 210 and the second support plate 270. Thereby, the uniformity of the temperature distribution in the surface of the heater plate 200 can be improved, and the uniformity of the temperature distribution in the surface of the processing object W can be improved. Further, the first support plate 210 and the second support plate 270 can block the heater element 230 (and a bypass layer 250 described later) from high frequency, and suppress the heater element 230 from generating heat to an abnormal temperature. .

  As described above, the power supply terminal 280 is provided from the heater plate 200 toward the base plate 300. Therefore, electric power can be supplied to the power supply terminal 280 from the side of the lower surface 303 (see FIGS. 2A and 2B) of the base plate 300 through a member called a socket. Thus, the heater wiring is realized while suppressing the power supply terminal 280 from being exposed in the chamber in which the electrostatic chuck 10 is installed.

Next, a method for manufacturing the heater plate 200 of this embodiment will be described.
In the method for manufacturing the heater plate 200 according to this embodiment, for example, the first support plate 210 and the second support plate 270 are manufactured by first machining aluminum. The inspection of the first support plate 210 and the second support plate 270 is performed using, for example, a three-dimensional measuring instrument.

  Next, for example, the first resin layer 220, the second resin layer 240, and the resin portion 223 are manufactured by cutting the polyimide film by laser, machining, die cutting, or melting. The inspection of the first resin layer 220, the second resin layer 240, and the resin portion 223 is performed using, for example, visual observation.

  Next, a heater pattern is formed by cutting a metal containing at least one of stainless steel, titanium, chromium, nickel, copper, and aluminum by etching, machining, die cutting, etc. using photolithography technology or printing technology. To do. Thereby, the heater element 230 is manufactured. Further, the resistance value of the heater element 230 is measured.

Then, the laminated body which laminated | stacked each member of the heater plate 200 is crimped | bonded.
Thus, the heater plate 200 of this embodiment is manufactured.
In addition, inspection etc. are suitably performed with respect to the heater plate 200 after manufacture.

The structure of the heater plate 200 according to the present embodiment will be further described with reference to the drawings.
FIG. 6 is a cross-sectional view showing a part of the heater plate of the present embodiment.
FIG. 7 is a photographic image of the heater plate of this embodiment. In FIG. 7, a cross section corresponding to the region B3 shown in FIG. 6 is observed.
In the present embodiment, the heater electrode 239 is disposed independently in a plurality of regions. For example, as illustrated in FIG. 6, the heater electrode 239 (heater element 230) includes the first conductive portion 21 and the second conductive portion 22. The second conductive portion 22 is separated from the first conductive portion 21 in the in-plane direction Dp (for example, the X direction). The first conductive part 21 and the second conductive part 22 are part of the heater electrode 239. The distance between the first conductive portion 21 and the second conductive portion 22 (the width L8 of the separation portion 235 between the first conductive portion 21 and the second conductive portion 22) is, for example, 500 μm or more. is there. Thus, the heater electrode 239 is arranged in a plurality of regions, whereby the temperature in the surface of the processing object W can be controlled for each region. A specific example of the pattern of the heater electrode 239 will be described later with reference to FIGS. 21 (a), 21 (b), and 22.

  For example, the upper surface of the first conductive portion 21 is in contact with the first resin layer 220, and the lower surface of the first conductive portion 21 is in contact with the second resin layer 240. For example, the upper surface of the second conductive portion 22 is in contact with the first resin layer 220, and the lower surface of the second conductive portion 22 is in contact with the second resin layer 240.

The heater plate 200 has a first resin part 221 (resin part 223). The first resin portion 221 is provided between the first resin layer 220 and the second resin layer 240 in the Z direction. For example, the upper surface of the first resin portion 221 is in contact with the first resin layer 220, and the lower surface of the first resin portion 221 is in contact with the second resin layer 240. The first resin portion 221 is provided between the first conductive portion 21 and the second conductive portion 22 in the in-plane direction Dp. In other words, the resin portion 223 is provided between each heater electrode 239. The first resin part 221 is separated from the first conductive part 21 and the second conductive part 22.
That is, the first resin layer 220 is in contact with the second resin layer 240 and the first resin portion 221 between the first conductive portion 21 and the second conductive portion 22.

  The first resin part 221 (resin part 223) is a resin layer different from the first resin layer 220 and the second resin layer 240. For example, the first resin portion 221 includes a material different from the material of the first resin layer 220. Different materials are materials having different compositions, materials having different physical properties (for example, melting point and glass transition point), or materials having different thermal histories. There is an interface between two materials with different thermal histories. The first resin portion 221 includes a material different from the material of the second resin layer 240. The thermal history of the first resin portion 221 is different from the thermal history of the first resin layer 220 and the second resin layer 240. The composition of the first resin portion 221 is different from the composition of the first resin layer 220 and the second resin layer 240.

  For example, when the first resin portion 221 includes a component different from the component included in the first resin layer 220, the material of the first resin portion 221 is different from the material of the first resin layer 220. Even when the first resin portion 221 includes the same component as the component of the first resin layer 220, the composition ratio (concentration) of the component in the first resin portion 221 is the composition of the component in the first resin layer 220. When the ratio (concentration) is different, the material of the first resin portion 221 is different from the material of the first resin layer 220. For example, even when the first resin layer 220 includes a plurality of layers, if the material of at least one of the plurality of layers is different from the material of the first resin portion 221, The material is different from the material of the first resin layer 220. The glass transition point (or melting point) of the first resin part 221 is, for example, lower than the glass transition point (or melting point) of the first resin layer 220. The same applies to the case where the material of the first resin portion 221 and the material of the second resin layer 220 are different.

  For example, polyimide, silicone, epoxy, acrylic, or the like is used for the material of the first resin portion 221. For example, a polyimide film, a foaming adhesive sheet, an adhesive containing silicone or epoxy can be used.

The first conductive portion 21 has a side end 21a (first side end) in the in-plane direction Dp. The side end portion 21a is an end portion on the first resin portion 221 side (an end portion on the second conductive portion 22 side).
Similarly, the second conductive portion 22 has a side end portion 22a in the in-plane direction Dp. The side end portion 22a is an end portion on the first resin portion 221 side (end portion on the first conductive portion 21 side).
The first resin portion 221 has a side end 221a and a side end 221b in the in-plane direction Dp. The side end portion 221a is an end portion on the first conductive portion 21 side, and the side end portion 221b is an end portion on the second conductive portion 22 side.

The heater plate 200 has a space 23a and a space 23b.
The space portion 23a (first space portion) includes at least the side end portion 21a of the first conductive portion 21, the first resin layer 220, the second resin layer 240, and the first resin portion 221 (side). It is a space defined (enclosed) by the end 221a). The space 23 a is adjacent to the side end 21 a in the in-plane direction Dp, and is located between the first conductive portion 21 and the first resin portion 221.

  Similarly, the space portion 23b includes at least the side end portion 22a of the second conductive portion 22, the first resin layer 220, the second resin layer 240, and the first resin portion 221 (side end portion 221b). It is a space that is partitioned (enclosed) by. The space portion 23b is adjacent to the side end portion 22a in the in-plane direction Dp, and is positioned between the second conductive portion 22 and the first resin portion 221.

  The length L2 along the Z direction of the space 23a is equal to or less than the length L1 along the Z direction of the first conductive portion 21. Similarly, the length of the space portion 23b along the Z direction is equal to or shorter than the length of the second conductive portion 22 along the Z direction.

  When a current flows through the heater electrode 239 and the heater plate 200 generates heat, the heater electrode 239 undergoes thermal expansion. For example, the thermal expansion coefficient of the first resin layer 220 and the thermal expansion coefficient of the heater electrode 239 may be different. Further, for example, the temperature of the first resin layer 220 and the temperature of the heater electrode 239 may be different. For this reason, when the heater electrode 239 is deformed by thermal expansion, stress is applied to the first resin layer 220. Due to this stress, the first resin layer 220 and the heater electrode 239 may be peeled off. In the region where the peeling occurs, heat conduction from the heater electrode 239 to the processing target W is hindered. For this reason, the temperature of the processing object W may fall locally.

  Similarly, the second resin layer 240 and the heater electrode 239 may peel off. In the region where peeling occurs, for example, heat conduction from the heater electrode 239 to the cooling medium is hindered. For this reason, the temperature of the processing object W may rise locally. When a local temperature change occurs in the processing object W, the accuracy of processing such as etching is lowered. As a result, the yield of semiconductor chips and the like may be reduced.

On the other hand, in the electrostatic chuck according to the embodiment, gaps (space portions 23a, 23b, etc.) are provided at each side end portion of the heater electrode 239 provided separately in a plurality of regions. Thereby, for example, the heater electrode 239 (the first conductive portion 21 and the like) can expand toward the gap. Even if the heater electrode 239 is deformed by thermal expansion, the gap is filled, so that the stress applied to the first resin layer 220 and the second resin layer 240 can be reduced. Thereby, peeling with the heater electrode 239 and the 1st resin layer 220 and peeling with the heater electrode 239 and the 2nd resin layer 240 can be suppressed. Therefore, resistance to load can be improved and reliability can be improved.
Moreover, it can suppress that heat conduction is inhibited locally by peeling, and can suppress the local temperature change of the process target W. That is, temperature uniformity and temperature controllability can be improved, and the temperature of the processing object can be controlled stably. Processing accuracy such as etching and the yield can be improved.

  Further, by providing the first resin portion 221 (resin portion 223) between the first resin layer 220 and the second resin layer 240, the first support plate 210 and the second support plate 270 are provided between each other. It is possible to control heat capacity and heat conduction. For example, the heat conduction and heat capacity of the heater plate can be adjusted by adjusting the material and shape of the first resin portion 221 (resin portion 223). Thereby, both temperature uniformity and thermal conductivity can be achieved.

FIG. 8 is a cross-sectional view showing a part of the heater plate of the present embodiment.
FIG. 8 shows a region including both ends in the in-plane direction Dp of the first conductive portion 21 shown in FIG.
In the example illustrated in FIG. 8, the heater plate 200 further includes a second resin portion 222 (resin portion 223). The second resin portion 222 is provided between the first resin layer 220 and the second resin layer 240 in the Z direction. For example, the upper surface of the second resin portion 222 is in contact with the first resin layer 220, and the lower surface of the second resin portion 222 is in contact with the second resin layer 240. The material and thickness of the second resin portion 222 can be the same as the material and thickness of the first resin portion 221, respectively.

  The first conductive portion 21 is located between the first resin portion 221 and the second resin portion 222 in the in-plane direction Dp. The first conductive portion 21 is separated from the first resin portion 221 and the second resin portion 222.

The first conductive portion 21 has a side end portion 21b (second side end portion) in the in-plane direction Dp. The side end portion 21b is an end portion on the second resin portion 222 side. That is, the side end 21b is an end opposite to the side end 21a.
The second resin portion 222 has a side end portion 222a in the in-plane direction Dp. The side end portion 222a is an end portion on the first conductive portion 21 side.

The heater plate 200 further has a space 23c.
The space part 23c (second space part) includes at least the side end part 21b of the first conductive part 21, the first resin layer 220, the second resin layer 240, and the second resin part 222 (side end). This is a space partitioned (enclosed) by the section 222a). The space portion 23 c is adjacent to the side end portion 21 b in the in-plane direction Dp, and is located between the first conductive portion 21 and the second resin portion 222.

  The length L3 along the Z direction of the space 23c is equal to or shorter than the length L1 along the Z direction of the first conductive portion 21.

  In the embodiment, the second resin portion 222 is not necessarily provided. That is, the space 23 c may be a space defined by the first conductive portion 21, the first resin layer 220, and the second resin layer 240.

  By providing the space portion 23c (second space portion) in this way, the first conductive portion 21 is deformed so as to fill the space portion 23c even if it is expanded by heat. Thereby, the stress concerning the 1st resin layer 220 and the 2nd resin layer 240 can be reduced similarly to the description regarding FIG. Further, as shown in FIG. 8, by providing a gap at both ends of the first conductive portion 21, reliability, temperature uniformity, temperature controllability, and the like can be further improved.

FIG. 9 is a cross-sectional view showing a part of the heater plate of the present embodiment.
FIG. 9 is an enlarged view for explaining the shape of the space portion 23a described above with reference to FIGS.
In this example, the thickness of the first conductive portion 21 (the length along the Z direction) is the same as the thickness of the first resin portion 221.

  In the cross section shown in FIG. 9 (a cross section parallel to the Z direction), the first resin layer 220 is a second resin layer between the first conductive portion 21 and the first resin portion 221. Separated from 240 (does not cross). In this cross section, the shape of the space 23a has four vertices Pt1 to Pt4. The vertex is a point (corner) at which the cross-sectional shape (contour) of the space portion is bent discontinuously. At the vertex Pt1, the first resin layer 220 and the first resin portion 221 intersect. At the vertex Pt2, the first resin layer 220 and the first conductive portion 21 intersect. At the vertex Pt3, the second resin layer 240 and the first resin portion 221 intersect. At the vertex Pt4, the second resin layer 240 and the first conductive portion 21 intersect.

  Since the space part 23a has the shape as described above, for example, the space between the first resin layer 220 and the second resin layer 240 is not narrower than a triangle having three vertices. Thereby, when the heater element (the first conductive portion 21) is deformed by heat, the stress applied to the first resin layer 220 and the second resin layer 240 can be easily reduced.

  As shown in FIG. 9, the space portion 23a includes both end portions (the end portion Ep1 and the end portion Ep2) in the in-plane direction Dp, and a central portion Cp1 located between the end portions Ep1 and Ep2. Have. The length L4 along the Z direction of the central portion Cp1 is shorter than the length L5 along the Z direction of the end portion Ep1 (or the end portion Ep2).

  That is, the space portion 23a is recessed in the Z direction and is expanded in the in-plane direction Dp. It is easy to relieve the thermal expansion by expanding the space in the in-plane direction Dp. Further, since the space portion is recessed in the Z direction and the space is secured, it is possible to achieve both relaxation of thermal expansion and improvement of heat transferability in the vertical direction.

  In this example, the space part 23a has a shape crushed from the upper side and the lower side as it approaches the center part in the in-plane direction Dp of the space part 23a. That is, the boundary between the space 23a and the first resin layer 220 approaches the virtual plane Pn1 (virtual line) illustrated in FIG. 9 as it approaches the central portion Cp1 in the in-plane direction Dp. Further, the boundary between the space 23a and the second resin layer 240 approaches the virtual surface Pn1 as it approaches the central portion Cp1 in the in-plane direction Dp. The virtual plane Pn1 is a plane that passes through the vicinity of the center in the Z direction of the first conductive portion 21 and is parallel to the in-plane direction Dp.

FIG. 10 is a cross-sectional view showing a part of another heater plate of the present embodiment.
In the example shown in FIG. 10, the length L6 (thickness) along the Z direction of the first resin portion 221 is shorter than the length L1 along the Z direction of the first conductive portion 21.

In the embodiment, the length L6 along the Z direction of the first resin portion 221 is desirably equal to or shorter than the length L1 along the Z direction of the first conductive portion 21.
If the first resin portion 221 (resin portion 223) is too thick, for example, when a heater element is manufactured by crimping each member, the resin layer (the first resin layer 220 or the second resin layer 240) and the heater are used. There is a possibility that the adhesion with the element (the first conductive portion 21) is lowered. By suppressing the thickness of the first resin portion 221 (resin portion 223), the adhesion between the resin layer and the heater element can be ensured. Thereby, the first resin layer 220 and the second resin layer 240 can be prevented from separating from the first conductive portion 21. Since the heater element and the resin layer can be adhered to each other, it is possible to achieve the designed thermal uniformity and withstand voltage characteristics. In addition, by ensuring the adhesion between the heater element and the resin layer, irregularities are formed on the upper surface of the first support plate 210. For this reason, the distance between a heater element and a process target object can be shortened. Thereby, the speed which raises the temperature of a process target object can be improved. Therefore, it is possible to achieve both “heating performance (heating rate) of the heater”, “temperature uniformity”, and “withstand voltage reliability”.

FIG. 11A and FIG. 11B are cross-sectional views showing a part of a modified example of the heater plate of the present embodiment.
In the example shown in FIG. 11A, the space 23a has a shape crushed from below as it approaches the central portion Cp1. That is, the boundary between the space 23a and the second resin layer 240 approaches the virtual surface Pn2 (virtual line) shown in FIG. 11A as it approaches the central portion Cp1 in the in-plane direction Dp. Further, the boundary between the space 23a and the first resin layer 220 extends along the virtual plane Pn2. The virtual surface Pn2 is a surface that passes through the upper surface 21U of the first conductive portion 21 and extends in the in-plane direction Dp. The upper surface 21U is a surface facing the first resin layer 220, and the first conductive portion 21 is in contact with the first resin layer 220 on the upper surface 21U. Similarly, the space 23b has a shape crushed from the lower side.

  In the example shown in FIG. 11B, the space portion 23a has a shape crushed from the upper side as it approaches the central portion Cp1. That is, the boundary between the space 23a and the first resin layer 220 approaches the virtual surface Pn3 (virtual line) illustrated in FIG. 11B as it approaches the center portion Cp1 in the in-plane direction Dp. Further, the boundary between the space 23a and the second resin layer 240 extends along the virtual plane Pn3. The virtual surface Pn3 is a surface that passes through the lower surface 21L of the first conductive portion 21 and extends in the in-plane direction Dp. The lower surface 21L is a surface facing the second resin layer 240, and the first conductive portion 21 is in contact with the second resin layer 240 on the lower surface 21L. Similarly, the space 23b has a shape crushed from the lower side.

  Since the space portions 23a and 23b have a shape crushed from either the upper side or the lower side, it is easier to secure the size of the space portions 23a and 23b during crimping than the shape crushed from both sides. The shape of the space portions 23a and 23b can be adjusted by adjusting the crimping conditions and the configuration (materials, etc.) of the laminate.

  In the example shown in FIGS. 11A and 11B, the length (width) along the in-plane direction Dp of the upper surface 21U is substantially the same as the length along the in-plane direction Dp of the lower surface 21L. .

12A and 12B are cross-sectional views showing a part of a modification of the heater plate of the present embodiment.
In the example shown in FIGS. 12A and 12B, the width of the upper surface of the heater electrode 239 is different from the width of the lower surface of the heater electrode 239. The length of the end of the heater electrode 239 varies vertically.

  Specifically, for example, the length L7 along the in-plane direction Dp of the upper surface 21U of the first conductive portion 21 is equal to the length L9 along the in-plane direction Dp of the lower surface 21L of the first conductive portion 21. Is different.

  FIG. 12A shows an example in which the width of the lower surface of the heater electrode 239 is wider than the width of the upper surface of the heater electrode 239. For example, the length L9 is longer than the length L7.

  In this case, stress applied to the layer in contact with the upper surface of the heater electrode 239 can be reduced, and peeling of the layer in contact with the upper surface of the heater electrode 239 can be suppressed. In the electrostatic chuck, heat easily escapes to the base plate 300 provided below the heater electrode 239, and the heat distribution may be biased in the vertical direction. On the other hand, as shown in FIG. 12A, since the lower surface of the heater electrode 239 is wide, the lower part of the heater electrode 239 can be easily heated. Thereby, the bias | inclination of the heat distribution in an up-down direction can be suppressed.

  FIG. 12B shows an example in which the width of the upper surface of the heater electrode 239 is wider than the width of the lower surface of the heater electrode 239. For example, the length L7 is longer than the length L9.

  In this case, stress applied to the layer in contact with the lower surface of the heater electrode 239 can be reduced, and peeling of the layer in contact with the lower surface of the heater electrode 239 can be suppressed. Further, since the upper surface of the heater electrode 239 is wide, the upper portion of the heater electrode 239 can be easily heated. Since the lower surface of the heater electrode 239 is narrow, the lower part of the heater electrode 239 can be easily cooled. Thereby, temperature followability (ramp plate) can be improved. The temperature follow-up property is the follow-up property of the temperature of the object to be processed when the set temperature is changed by changing the output of the heater or the like, and is related to the heating performance (temperature increase rate).

The heater electrode 239 has a side surface that connects the upper surface and the lower surface. The side surface is a surface that is in contact with the space portion (gap) adjacent to the heater electrode 239. This side surface is rougher than the surface of the upper surface and the lower surface of the heater electrode 239 that is wider in the in-plane direction.
For example, the first conductive portion 21 has a side surface S1 and a side surface S2 that connect the upper surface 21U and the lower surface 21L. The side surface S1 is a surface in contact with the first space portion 23a. The side surface S2 is a surface opposite to the side surface S1. Each of the side surface S1 and the side surface S2 is rougher than at least one of the upper surface 21U and the lower surface 21L. For example, in the example shown in FIG. 12A, each of the side surface S1 and the side surface S2 is rougher than the lower surface 21L. In the example shown in FIG. 12B, each of the side surface S1 and the side surface S2 is rougher than the upper surface 21U.

  When the side surface is rougher than at least one of the upper surface and the lower surface of the conductive portion, thermal diffusion from the side surface is improved, and thermal characteristics such as thermal uniformity and temperature followability can be improved.

FIG. 13A and FIG. 13B are cross-sectional views showing a part of a modified example of the heater plate of the present embodiment. These drawings are enlarged views for explaining the shape of the first conductive portion 21.
FIG. 13A and FIG. 13B show the first conductive portion 21 shown in FIG. 12A and the first conductive portion 21 shown in FIG. 12B, respectively.

As shown in FIG. 13A and FIG. 13B, in the cross section parallel to the Z direction, each of the side surface S1 and the side surface S2 is curved.
In the example of FIG. 13A, the side surface S1 and the side surface S2 are each a concave curved surface (concave toward the bottom). In the example of FIG. 13B, each of the side surface S1 and the side surface S2 is a concave curved surface (concave upward). The side surface S1 and the side surface S2 may be planar.

  By adjusting the shape of the curved surfaces as described above of the side surface S1 and the side surface S2, for example, the space portion 23a and the space portion 23c are widened or formed in the first resin layer 220 and the second resin layer 240. The unevenness can be enlarged. Thereby, heating performance (temperature increase rate), temperature uniformity, and withstand voltage reliability can be further improved.

  Further, the angle θ1 between the upper surface 21U and the side surface S1 is different from the angle θ2 between the lower surface 21L and the side surface S1. As a result, it is possible to achieve both the reduction of the peeling of the resin layer adjacent to the heater element due to the relaxation of the stress to the resin layer due to the deformation of the heater due to thermal expansion, and the thermal characteristics such as the soaking property and the temperature followability.

FIG. 14A to FIG. 14D are cross-sectional views showing a part of a modified example of the heater plate of the present embodiment.
The first support plate 210 includes a first support part SP1 and a second support part SP2. The first support portion SP1 is aligned with the first conductive portion 21 in the Z direction. The second support portion SP2 is aligned with the space portion 23a in the Z direction.
Similarly, the second support plate 270 includes a third support part SP3 and a fourth support part SP4. The third support portion SP3 is aligned with the first conductive portion 21 in the Z direction. The fourth support portion SP4 is aligned with the space portion 23a in the Z direction.

  As shown in FIGS. 14A to 14C, the length L10 (distance) between the second support portion SP2 and the fourth support portion SP4 is the same as that of the first support portion SP1 and the third support portion SP1. This is shorter than the length L11 (distance) between the support portion SP3. That is, irregularities are formed on at least one of the first support plate 210 and the second support plate 270.

  FIG. 14A shows an example in which irregularities are formed on both the first support plate 210 and the second support plate 270. In this example, the first support part SP1 and the third support part SP3 are flat, and the second support part SP2 and the fourth support part SP4 are recessed.

  FIG. 14B shows an example in which unevenness is formed on the first support plate 210 and no unevenness is formed on the second support plate 270. In this example, the first support part SP1, the third support part SP3, and the fourth support part SP4 are flat, and the second support part SP2 is recessed.

  FIG. 14C shows an example in which unevenness is formed on the second support plate 270 and no unevenness is formed on the first support plate 210. In this example, the first support part SP1, the second support part SP2, and the third support part SP3 are flat, and the fourth support part SP4 is recessed.

  Such unevenness of the support plate is formed by high adhesion between the heater element (first conductive portion 21) and a member sandwiching the heater element. Due to the high adhesion, for example, variations can be suppressed and heat conduction can be easily controlled. For example, it is possible to achieve soaking and voltage resistance characteristics as designed. In addition, since the convex portion is formed on the first support plate 210, the distance between the heater element and the object to be processed can be shortened. Thereby, the speed which raises the temperature of a process target object can be improved. In addition, by forming a flat portion on the support plate, the thickness of the adhesive 403 can be easily controlled, and variations can be reduced.

In FIG. 14D, the length L10 is substantially the same as the length L11. “Substantially the same” means, for example, that the length L10 is about 0.9 to 1.1 times the length L11. In FIG. 14D, the first support plate 210 and the second support plate 270 are flat. As a result, variations in the thickness of the adhesive 403 that joins the heater plate 200, the ceramic dielectric substrate 100, and the base plate 300 can be reduced, and in-plane heat transfer can be made uniform.
In addition, the distance between the heater element and the object to be processed is reduced over the entire surface, and the speed at which the temperature of the object to be processed is increased can be improved. Therefore, it is possible to achieve both “heater heating performance (temperature increase rate)” and “temperature uniformity”.

FIG. 15 is a schematic exploded view showing a modification of the heater plate of the present embodiment.
As shown in FIG. 15, the heater plate 200 may include a bypass layer 250 and a third resin layer 260. The bypass layer 250 is provided between the second resin layer 240 and the second support plate 270. The third resin layer 260 is provided between the bypass layer 250 and the second support plate 270. Except for this, the same explanation as the above-described heater plate can be applied to the heater plate of the modification shown in FIG. In FIG. 15, the resin portion 223 is not shown for convenience of explanation.

  The third resin layer 260 joins the bypass layer 250 and the second support plate 270 to each other. The third resin layer 260 electrically insulates between the bypass layer 250 and the second support plate 270. Thus, the third resin layer 260 has a function of electrical insulation and a function of surface bonding. The material and thickness of the third resin layer 260 are approximately the same as the material and thickness of the first resin layer 220, respectively.

  In this example, the second resin layer 240 joins the heater element 230 and the bypass layer 250 to each other. The second resin layer 240 electrically insulates between the heater element 230 and the bypass layer 250.

  The bypass layer 250 is disposed substantially parallel to the first support plate 210 and is disposed substantially parallel to the second support plate 270. The bypass layer 250 has a plurality of bypass portions 251. The bypass layer 250 has, for example, eight bypass parts 251. The number of bypass units 251 is not limited to “8”. The bypass layer 250 has a plate shape. When viewed perpendicular to the surface of the bypass layer 250 (surface 251a of the bypass portion 251), the area of the bypass layer 250 is larger than the area of the heater element 230 (area of the heater electrode 239). Details of this will be described later.

  The bypass layer 250 has conductivity. The bypass layer 250 is electrically insulated from the first support plate 210 and the second support plate 270. Examples of the material of the bypass layer 250 include metals including stainless steel. The thickness of the bypass layer 250 (the length in the Z direction) is, for example, about 0.03 mm or more and 0.30 mm or less. The bypass layer 250 is thicker than the first resin layer 220. The bypass layer 250 is thicker than the second resin layer 240. The bypass layer 250 is thicker than the third resin layer 260.

  For example, the material of the bypass layer 250 is the same as the material of the heater element 230. On the other hand, the bypass layer 250 is thicker than the heater element 230. Therefore, the electrical resistance of the bypass layer 250 is lower than the electrical resistance of the heater element 230. Thereby, even when the material of the bypass layer 250 is the same as the material of the heater element 230, the heat generation of the bypass layer 250 like the heater element 230 can be suppressed. That is, the electrical resistance of the bypass layer 250 can be suppressed, and the heat generation amount of the bypass layer 250 can be suppressed. The means for suppressing the electrical resistance of the bypass layer 250 and suppressing the heat generation amount of the bypass layer 250 may be realized by using a material having a relatively low volume resistivity instead of the thickness of the bypass layer 250. That is, the material of the bypass layer 250 may be different from the material of the heater element 230. Examples of the material of the bypass layer 250 include metals including at least one of stainless steel, titanium, chromium, nickel, copper, and aluminum.

  The power supply terminal 280 is electrically joined to the heater element 230 via the bypass layer 250. One power supply terminal 280 is electrically joined to one bypass layer 250. When electric power is supplied from the outside of the electrostatic chuck 10 to the power supply terminal 280 as indicated by arrows C1 and C2 illustrated in FIG. 15, current flows from the power supply terminal 280 to the bypass layer 250. As indicated by arrows C <b> 3 and C <b> 4 illustrated in FIG. 15, the current that has flowed to the bypass layer 250 flows from the bypass layer 250 to the heater element 230. As indicated by arrows C5 and C6 shown in FIG. 15, the current flowing to the heater element 230 flows through a predetermined zone (region) of the heater element 230 and flows from the heater element 230 to the bypass layer 250. As indicated by arrows C7 and C8 shown in FIG. 15, the current that flows to the bypass layer 250 flows from the bypass layer 250 to the power supply terminal 280. As indicated by an arrow C <b> 9 illustrated in FIG. 15, the current that flows to the power supply terminal 280 flows to the outside of the electrostatic chuck 10.

  As described above, the bypass layer 250 is provided between the heater element 230 and the second support plate 270. That is, the bypass layer 250 is provided between the heater element 230 and the base plate 300. The thermal conductivity of stainless steel is lower than that of aluminum and copper. Therefore, the bypass layer 250 suppresses the heat supplied from the heater element 230 from being transmitted to the second support plate 270. That is, the bypass layer 250 has a heat insulating effect on the second support plate 270 side when viewed from the bypass layer 250, and can improve the uniformity of the temperature distribution in the surface of the processing object W.

  The bypass layer 250 can have a greater degree of freedom with respect to the arrangement of the power supply terminals 280. By providing the bypass layer 250, it is not necessary to directly join the power supply terminal having a large heat capacity to the heater element 230 as compared to the case where the bypass layer 250 is not provided. Thereby, the uniformity of the temperature distribution in the surface of the processing target W can be improved. Further, it is not necessary to join the power supply terminal 280 to the thin heater element 230 as compared with the case where the bypass layer 250 is not provided. Thereby, the reliability of the heater plate 200 can be improved.

Next, a method for manufacturing the heater plate shown in FIG. 15 will be described.
FIG. 16A and FIG. 16B are schematic cross-sectional views illustrating an example of the manufacturing method of this embodiment.
FIG. 17 is a schematic cross-sectional view illustrating another example of the manufacturing method of this embodiment.
Fig.16 (a) is typical sectional drawing showing the state before joining a bypass layer and a heater element. FIG.16 (b) is typical sectional drawing showing the state after joining a bypass layer and a heater element. FIG. 17 is a schematic cross-sectional view illustrating an example of a joining process between the bypass layer and the power supply terminal.

  First, each member of the heater plate 200 is prepared in the same manner as the manufacturing method described with reference to FIG. Subsequently, as shown in FIGS. 16A and 16B, the heater element 230 and the bypass layer 250 are joined. The heater element 230 and the bypass layer 250 are joined by soldering, brazing, welding, or contact. As shown in FIG. 16A, the second resin layer 240 is provided with a hole 241. The hole 241 passes through the second resin layer 240. For example, the heater element 230 and the bypass layer 250 are joined by performing spot welding from the bypass layer 250 side as indicated by an arrow C11 shown in FIG.

  The joining of the heater element 230 and the bypass layer 250 is not limited to welding. For example, the heater element 230 and the bypass layer 250 may be joined by joining using laser light, soldering, brazing, or contact. Then, the laminated body which laminated | stacked each member of the heater plate 200 is crimped | bonded.

Subsequently, as illustrated in FIG. 17, the power feeding terminal 280 and the bypass layer 250 are joined. The power supply terminal 280 and the bypass layer 250 are joined by welding, laser, soldering, brazing, or the like. As shown in FIG. 17, the second support plate 270 is provided with a hole 273. The hole 273 passes through the second support plate 270. This is as described above with reference to FIG. A hole 261 is provided in the third resin layer 260. The hole 261 passes through the third resin layer 260. By performing welding, laser, soldering, brazing, or the like from the second support plate 270 to the first support plate 210 as indicated by an arrow C13 illustrated in FIG. And join.
Thus, the heater plate 200 of this embodiment is manufactured.

  In the following description, a case where the heater plate has the bypass layer 250 and the third resin layer 260 will be described as an example. However, in the embodiment, the bypass layer 250 and the third resin layer 260 may be omitted as in the heater plate described with reference to FIGS. Since the configuration other than the bypass layer 250 and the third resin layer 260 is the same, detailed description thereof is omitted.

FIG. 18 is a schematic exploded view showing the electrostatic chuck according to the present embodiment.
FIG. 19A and FIG. 19B are electric circuit diagrams showing an electrostatic chuck.
FIG. 19A is an electric circuit diagram illustrating an example in which the first support plate and the second support plate are electrically joined. FIG. 19B is an electric circuit diagram illustrating an example in which the first support plate and the second support plate are not electrically joined.

  As shown in FIG. 18 and FIG. 19A, the first support plate 210 is electrically joined to the second support plate 270. The first support plate 210 and the second support plate 270 are joined by, for example, welding, joining using laser light, soldering, or contact.

  For example, as illustrated in FIG. 19B, if the first support plate 210 is not electrically and reliably joined to the second support plate 270, the first support plate 210 is the second support plate. 270 may be electrically joined or not electrically joined. Then, the etching rate when plasma is generated may vary. Even if the first support plate 210 is not electrically joined to the second support plate 270, current may flow to the heater element 230 when the plasma is generated, and the heater element 230 may generate heat. In other words, if the first support plate 210 is not securely joined to the second support plate 270, the heater element 230 may generate heat due to a current other than the heater current.

  On the other hand, in the electrostatic chuck 10 according to the present embodiment, as shown in FIG. 19A, the first support plate 210 is electrically joined to the second support plate 270. As a result, the current flows from the first support plate 210 to the second support plate 270, or the current flows from the second support plate 270 to the first support plate 210, resulting in an etching rate when plasma is generated. The occurrence of variations can be suppressed. Further, the heater element 230 can be prevented from generating heat due to a current other than the heater current.

  Furthermore, the heater element 230 and the bypass layer 250 can be shielded from high frequencies. Thereby, it is possible to suppress the heater element 230 from generating heat to an abnormal temperature. Moreover, the impedance of the heater plate 200 can be suppressed.

Next, a specific example of the heater plate 200 of the present embodiment will be described with reference to the drawings.
FIG. 20A and FIG. 20B are schematic plan views showing specific examples of the heater plate of the present embodiment.
FIG. 21A, FIG. 21B, and FIG. 22 are schematic plan views illustrating the heater element of this example.
FIG. 23A and FIG. 23B are schematic plan views illustrating the bypass layer of this example.
FIG. 24A and FIG. 24B are enlarged views schematically showing a part of the heater plate of this specific example.
FIG. 20A is a schematic plan view of the heater plate of this specific example as viewed from above. FIG. 20B is a schematic plan view of the heater plate of this specific example viewed from the bottom surface. FIG. 21A is a schematic plan view illustrating an example of the heater element region. FIG. 21B and FIG. 22 are schematic plan views illustrating another example of the heater element region.

As shown in FIG. 23, at least one of the plurality of bypass portions 251 of the bypass layer 250 has a notch 253 at the edge. In the bypass layer 250 shown in FIG. 23, four cutout portions 253 are provided. The number of notches 253 is not limited to “4”.
Since at least one of the plurality of bypass layers 250 has the cutout portion 253, the second support plate 270 can contact the first support plate 210.

  As shown in FIGS. 20A and 20B, the first support plate 210 is electrically joined to the second support plate 270 in the regions B11 to B14 and the regions B31 to B34. Yes. Each of the regions B11 to B14 corresponds to each of the regions B31 to B34. That is, in the specific examples shown in FIGS. 20A to 22, the first support plate 210 is electrically joined to the second support plate 270 in four regions, and the second support plate 210 in the eight regions. The support plate 270 is not electrically joined.

  FIGS. 24A and 24B are enlarged views illustrating an example of the region B31 (region B11). FIG. 24A is a schematic plan view of the region B31, and FIG. 24B is a schematic cross-sectional view of the region B31. FIG. 24B schematically shows a cut surface A2-A2 of FIG. Since the other regions B12 to B14 and the regions B32 to B34 are the same as the regions B11 and B31, detailed description thereof is omitted.

  As illustrated in FIG. 24A and FIG. 24B, the bonding region JA is provided in the region B31. The joint area JA joins the first support plate 210 and the second support plate 270 to each other. The joining area JA is provided on the outer edge of the first support plate 210 and the second support plate 270 corresponding to the notch 253 of the bypass layer 250. The joining area JA is formed by, for example, laser welding from the second support plate 270 side. Thereby, the joining area JA is formed in a spot shape. The bonding area JA may be formed from the first support plate 210 side. In addition, the formation method of joining area | region JA is not restricted to laser welding, Another method may be sufficient. The shape of the bonding area JA is not limited to a spot shape, and may be an elliptical shape, a semicircular shape, a square shape, or the like.

  The area of the joint area JA where the first support plate 210 is joined to the second support plate 270 is smaller than the area of the surface 211 (see FIG. 3) of the first support plate 210. The area of the bonding area JA is smaller than the area of the difference obtained by subtracting the area of the heater element 230 from the area of the surface 211. In other words, the area of the bonding area JA is smaller than the area of the area that does not overlap the heater element 230 when projected onto a plane parallel to the surface 211 of the first support plate 210. The area of the joint area JA where the first support plate 210 is joined to the second support plate 270 is smaller than the area of the surface 271 of the second support plate 270 (see FIG. 4A). The area of the bonding area JA is smaller than the area of the difference obtained by subtracting the area of the heater element 230 from the area of the surface 271. In other words, the area of the bonding area JA is smaller than the area of the area that does not overlap the heater element 230 when projected onto a plane parallel to the surface 271 of the second support plate 270.

  The diameter of the joining area JA formed in a spot shape is, for example, 1 mm (0.5 mm or more and 3 mm or less). On the other hand, the diameters of the first support plate 210 and the second support plate 270 are, for example, 300 mm. The diameters of the first support plate 210 and the second support plate 270 are set according to the processing object W to be held. Thus, the area of the bonding area JA is sufficiently smaller than the area of the surface 211 of the first support plate 210 and the area of the surface 271 of the second support plate 270. The area of the bonding region JA is, for example, 1/5000 or less of the area of the surface 211 (area of the surface 271). Here, the area of the bonding area JA is more specifically the area when projected onto a plane parallel to the surface 211 of the first support plate 210. In other words, the area of the bonding area JA is an area in a top view.

  In this example, four joint regions JA corresponding to the regions B11 to B14 and the regions B31 to B34 are provided. The number of joining areas JA is not limited to four. The number of the joining areas JA may be an arbitrary number. For example, twelve bonding areas JA may be provided on the first support plate 210 and the second support plate 270 every 30 °. Further, the shape of the bonding area JA is not limited to a spot shape. The shape of the bonding area JA may be elliptical, square, linear, or the like. For example, the joining area JA may be formed in an annular shape along the outer edges of the first support plate 210 and the second support plate 270.

  The second support plate 270 has a hole 273 (see FIG. 4B and FIG. 17). On the other hand, the first support plate 210 does not have a hole through which the power supply terminal 280 passes. Therefore, the area of the surface 211 of the first support plate 210 is larger than the area of the surface 271 of the second support plate 270.

  In the specific example shown in FIG. 21A, the heater electrode 239 is arranged so as to draw a substantially circle. The heater electrode 239 is disposed in the first region 231, the second region 232, the third region 233, and the fourth region 234. The first region 231 is located at the center of the heater element 230. The second region 232 is located outside the first region 231. The third region 233 is located outside the second region 232. The fourth region 234 is located outside the third region 233.

  The heater electrode 239 disposed in the first region 231 is not electrically joined to the heater electrode 239 disposed in the second region 232. The heater electrode 239 disposed in the second region 232 is not electrically joined to the heater electrode 239 disposed in the third region 233. The heater electrode 239 disposed in the third region 233 is not electrically joined to the heater electrode 239 disposed in the fourth region 234. That is, the heater electrode 239 is provided in a plurality of regions in an independent state.

  For example, the first conductive portion 21 described with reference to FIG. 5 is the heater electrode 239 disposed in the second region 232, and the second conductive portion 22 is the heater electrode 239 disposed in the third region 233. It is. Alternatively, the first conductive portion 21 may be the heater electrode 239 disposed in the third region 233, and the second conductive portion 22 may be the heater electrode 239 disposed in the fourth region 234. .

  In the specific example shown in FIG. 21B, the heater electrode 239 is arranged so as to draw at least a part of a substantially fan shape. The heater electrode 239 includes a first region 231a, a second region 231b, a third region 231c, a fourth region 231d, a fifth region 231e, a sixth region 231f, and a seventh region. The region 232a, the eighth region 232b, the ninth region 232c, the tenth region 232d, the eleventh region 232e, and the twelfth region 232f are arranged. The heater electrode 239 arranged in an arbitrary region is not electrically joined to the heater electrode 239 arranged in another region. That is, the heater electrode 239 is provided in a plurality of regions in an independent state. As shown in FIGS. 21A and 21B, the region where the heater electrode 239 is disposed is not particularly limited.

  In the specific example shown in FIG. 22, the heater element 230 has more regions. In the heater element 230 of FIG. 20, the first region 231 shown in FIG. 22A is further divided into four regions 231a to 231d. Further, the second region 232 shown in FIG. 22A is further divided into eight regions 232a to 232h. Further, the third region 233 shown in FIG. 22A is further divided into eight regions 233a to 233h. The fourth area 234 shown in FIG. 22A is further divided into 16 areas 234a to 234p. As described above, the number and shape of the regions of the heater element 230 in which the heater electrode 239 is disposed may be arbitrary.

  As shown in FIG. 23A, the bypass portion 251 of the bypass layer 250 has a fan shape. A plurality of fan-shaped bypass portions 251 are arranged apart from each other, and the bypass layer 250 has a substantially circular shape as a whole. As shown in FIG. 23A, the separation portion 257 between the adjacent bypass portions 251 extends in the radial direction from the center 259 of the bypass layer 250. In other words, the separation portion 257 between the adjacent bypass portions 251 extends radially from the center 259 of the bypass layer 250. The area of the surface 251 a of the bypass part 251 is larger than the area of the separation part 257. The area of the bypass layer 250 (area of the surface 251a of the bypass portion 251) is larger than the area of the heater element 230 (area of the heater electrode 239).

  As shown in FIG. 23B, the shape of the plurality of bypass portions 251 of the bypass layer 250 may be, for example, a curved fan shape. Thus, the number and shape of the plurality of bypass portions 251 provided in the bypass layer 250 may be arbitrary.

  In the following description regarding FIGS. 20A to 23B, the region of the heater element 230 illustrated in FIG. 21A is taken as an example. The heater electrode 239 is disposed so as to draw a substantially circle, and a plurality of fan-shaped bypass portions 251 are arranged apart from each other. Therefore, when viewed perpendicular to the surface 251 a of the bypass portion 251, the heater electrode 239 intersects with the separation portion 257 between the adjacent bypass portions 251. Further, when viewed perpendicular to the surface 251 a of the bypass portion 251, each region of the adjacent heater element 230 (the first region 231, the second region 232, the third region 233, and the fourth region 234). ) Between the adjacent bypass portions 251 intersects with the separation portion 257 between the adjacent bypass portions 251.

  As shown in FIG. 20A and FIG. 20B, a plurality of imaginary lines connecting each of the joint portions 255a to 255h between the heater element 230 and the bypass layer 250 and the center 203 of the heater plate 200 are , Do not overlap each other. In other words, the joint portions 255 a to 255 h between the heater element 230 and the bypass layer 250 are arranged in different directions as viewed from the center 203 of the heater plate 200. As illustrated in FIG. 20B, the power supply terminal 280 exists on an imaginary line that connects each of the joint portions 255 a to 255 h and the center 203 of the heater plate 200.

  The joint portions 255 a and 255 b are portions that join the heater electrode 239 and the bypass layer 250 disposed in the first region 231. The joint portions 255a and 255b correspond to the first region 231. One of the joint portion 255a and the joint portion 255b is a portion where current enters the heater element 230. The other of the joining portion 255a and the joining portion 255b is a portion where current flows out of the heater element 230.

  The joint portions 255 c and 255 d are portions that join the heater electrode 239 and the bypass layer 250 disposed in the second region 232. The joint portions 255 c and 255 d correspond to the second region 232. One of the joint portion 255c and the joint portion 255d is a portion where current enters the heater element 230. The other of the joining portion 255c and the joining portion 255d is a portion where current flows out of the heater element 230.

  The joining portions 255e and 255f are portions that join the heater electrode 239 and the bypass layer 250 disposed in the third region 233. The joint portions 255e and 255f correspond to the third region 233. One of the joint portion 255e and the joint portion 255f is a portion where current enters the heater element 230. The other of the joining portion 255e and the joining portion 255f is a portion where the current exits from the heater element 230.

  The joint portions 255g and 255h are portions that join the heater electrode 239 and the bypass layer 250 disposed in the fourth region 234. The joint portions 255g and 255h correspond to the fourth region 234. One of the junction 255g and the junction 255h is a portion where current enters the heater element 230. The other of the joining portion 255g and the joining portion 25h is a portion where current flows out of the heater element 230.

The joint portions 255a and 255b exist on a circle different from the circle passing through the joint portions 255c and 255d with the center 203 of the heater plate 200 as the center. The joint portions 255a and 255b exist on a circle different from the circle passing through the joint portions 255e and 255f with the center 203 of the heater plate 200 as the center. The joints 255a and 255b exist on a circle different from the circle passing through the joints 255g and 255h with the center 203 of the heater plate 200 as the center.
The joint portions 255c and 255d exist on a circle different from the circle passing through the joint portions 255e and 255f with the center 203 of the heater plate 200 as the center. The joint portions 255c and 255d exist on a circle different from the circle passing through the joint portions 255g and 255h with the center 203 of the heater plate 200 as the center.
The joint portions 255e and 255f exist on a circle different from the circle passing through the joint portions 255g and 255h with the center 203 of the heater plate 200 as the center.

  As shown in FIGS. 20A and 20B, the heater plate 200 has a lift pin hole 201. In the specific examples shown in FIGS. 20A and 20B, the heater plate 200 has three lift pin holes 201. The number of lift pin holes 201 is not limited to “3”. The power supply terminal 280 is provided in a region on the side of the center 203 of the heater plate 200 when viewed from the lift pin hole 201.

  According to this specific example, since the heater electrode 239 is disposed in a plurality of regions, the temperature in the surface of the processing object W can be controlled independently for each region. Thereby, it is possible to intentionally make a difference in the in-plane temperature of the processing object W (temperature controllability).

FIG. 25A and FIG. 25B are schematic views for explaining the shape of the surface of the heater plate of the present embodiment.
FIG. 25A is a graph illustrating an example of a result of measurement of the shape of the surface 271 of the second support plate 270 by the inventor. FIG. 25B is a schematic cross-sectional view illustrating the shape of the surface of the heater plate 200 of the present embodiment.

  As described above, each member of the heater plate 200 is pressure-bonded in a stacked state. At this time, as shown in FIG. 25B, the first unevenness is generated on the surface 211 (upper surface) of the first support plate 210. The second unevenness is generated on the surface 271 (lower surface) of the second support plate 270. In addition, a third unevenness is generated on the surface 213 (lower surface) of the first support plate 210. A fourth unevenness is generated on the surface 275 (upper surface) of the second support plate 270.

  The inventor measured the shape of the surface 271 of the second support plate 270. An example of the measurement result is as shown in FIG. As shown in FIGS. 25A and 25B, the shape of the surface 211 (upper surface) of the first support plate 210 and the shape of the surface 271 of the second support plate 270 are the same as the shape of the heater element 230. Alternatively, the heater element 230 is arranged. The shape of the heater element 230 refers to the thickness of the heater element 230 and the width of the heater element 230 (the width of the heater electrode 239).

  Z between the concave portion 211a (first concave / convex concave portion 211a) of the surface 211 of the first support plate 210 and the concave portion 271a (second concave / convex concave portion 271a) of the surface 271 of the second support plate 270. The distance D1 in the direction is such that the convex portion 211b (first concave / convex convex portion 211b) of the surface 211 of the first support plate 210 and the convex portion 271b (second concave / convex portion of the surface 271 of the second supporting plate 270). It is shorter than the distance D2 in the Z direction between the convex portion 271b).

  The distance D3 in the Z direction between the concave portion 211a of the surface 211 of the first support plate 210 and the convex portion 211b of the surface 211 of the first support plate 210 (the uneven height of the surface 211 of the first support plate 210) (The height of the first unevenness) is a distance D4 (Z4) between the concave portion 271a of the surface 271 of the second support plate 270 and the convex portion 271b of the surface 271 of the second support plate 270. The unevenness height of the surface 271 of the second support plate 270 is shorter than the height of the second unevenness. That is, the unevenness height (first unevenness height) of the surface 211 of the first support plate 210 is higher than the unevenness height (second unevenness height) of the surface 271 of the second support plate 270. Low.

  A distance D8 in the Z direction between the concave portion 213a of the surface 213 of the first support plate 210 and the convex portion 213b of the surface 213 of the first support plate 210 (the uneven height of the surface 213 of the first support plate 210) Is a distance D9 in the Z direction (surface of the second support plate 270) between the concave portion 275a of the surface 275 of the second support plate 270 and the convex portion 275b of the surface 275 of the second support plate 270. Shorter than the concavo-convex height of 275). That is, the uneven height of the surface 213 of the first support plate 210 is lower than the uneven height of the surface 275 of the second support plate 270.

  The width of the concave portion 271a of the surface 271 of the second support plate 270 is the same as the width of the region between the heater electrode 239 (for example, the first conductive portion 21) and the resin portion 223 (for example, the first resin portion 221). Degree. The width of the concave portion 271a of the surface 271 of the second support plate 270 is, for example, not less than 0.25 times and not more than 2.5 times the width of the region between the adjacent heater electrode 239 and the resin portion.

The width of the convex portion 271 b of the surface 271 of the second support plate 270 is, for example, approximately the same as the width of the heater electrode 239 or approximately the same as the width of the resin portion 223. The width of the convex portion 271b of the surface 271 of the second support plate 270 is, for example, not less than 0.8 times and not more than 1.2 times the width of the heater electrode 239.

  Further, the uneven height D4 of the surface 271 of the second support plate 270 is approximately the same as the thickness of the heater element 230 (the thickness of the heater electrode 239) or approximately the same as the thickness of the resin portion 223. The unevenness height D4 of the second support plate 270 is, for example, not less than 0.8 times and not more than 1.2 times the thickness of the heater element 230.

  Similarly, the width of the concave portion 211a of the surface 211 of the first support plate 210 is the width of the region between the heater electrode 239 (for example, the first conductive portion 21) and the resin portion 223 (for example, the first resin portion 221). It is about the same as the width. The width of the convex portion 211 b of the surface 211 of the first support plate 210 is about the same as the width of the heater electrode 239 or the width of the resin portion 223. On the other hand, the uneven height D 3 of the surface 211 of the first support plate 210 is lower than the thickness of the heater element 230.

  The height of the surface 271 of the second support plate 270 changes gradually from the convex portion 271b toward the adjacent concave portion 271a. For example, the height of the surface 271 of the second support plate 270 continuously decreases from the center in the width direction of the convex portion 271b toward the center in the width direction of the adjacent concave portion 271a. More specifically, the center in the width direction of the convex portion 271b is a position overlapping the center in the width direction of the heater electrode 239 in the surface 271 in the Z direction, or the center in the width direction of the resin portion 223 in the surface 271. It is a position that overlaps in the Z direction. More specifically, the center in the width direction of the concave portion 271a is a position overlapping in the Z direction with the center in the width direction of the region between the adjacent heater electrode 239 and the resin portion 223 in the surface 271.

  As described above, the height of the surface 271 of the second support plate 270 has a wavy shape with the portion overlapping the heater electrode 239 and the resin portion 223 as the apex, and the portion not overlapping the heater electrode 239 and the resin portion 223 as the lowest point. To change. Similarly, the height of the surface 211 of the first support plate 210 has a wave shape with the portion overlapping with the heater electrode 239 and the resin portion 223 as the apex and the portion not overlapping with the heater electrode 239 and the resin portion 223 as the lowest point. Change.

  According to this embodiment, since the surface 211 of the first support plate 210 has the first unevenness, the bonding area between the first support plate 210 and the heater element 230 can be further increased, and the first The adhesive strength between the one support plate 210 and the heater element 230 can be improved. Moreover, the adhesion area of the 1st support plate 210 and the adhesive agent 403 can be made wider according to the 1st unevenness | corrugation. Thereby, the joint strength between the first support plate 210 and the adhesive 403 can also be improved. Further, since the first support plate 210 has irregularities, the rigidity of the first support plate 210 is increased. For this reason, even if the 1st support plate 210 is thin, the curvature and deformation | transformation of the heater plate 200 can be reduced. Thereby, for example, it is possible to achieve both “reduction of the warpage of the heater plate” and “reduction of heat capacity” that affect high throughput, which are generally in a trade-off relationship. In addition, since the surface 271 of the second support plate 270 has the second unevenness, the adhesion area between the second support plate 270 and the bypass layer 250 can be increased, and the second support plate 270 can be increased. And the adhesive strength between the bypass layer 250 can be improved. Moreover, the adhesion area of the 2nd support plate 270 and the adhesive agent 403 can be made wider according to the 2nd unevenness | corrugation. Thereby, the joint strength between the second support plate 270 and the adhesive 403 can also be improved. In addition, since the second support plate 270 has irregularities, the rigidity of the second support plate 270 increases. For this reason, even if the 2nd support plate 270 is thin, the curvature and deformation | transformation of the heater plate 200 can be reduced. Thereby, for example, it is possible to achieve both “reduction of the warpage of the heater plate” and “reduction of heat capacity” that affect high throughput, which are generally in a trade-off relationship. Furthermore, since the surface 211 of the first support plate 210 has the first unevenness, the distance between the heater element 230 and the processing object W can be further shortened. Thereby, the speed which raises the temperature of the processing target object W can be improved.

  Note that the first and second uneven heights can be controlled depending on, for example, the pressure bonding conditions and the configuration (material, etc.) of the laminate.

  Further, since the heater element 230 generates heat, the heater element 230 itself is likely to be thermally distorted. On the other hand, in the specific example shown in FIG. 25B, the unevenness (distortion) in the first support plate 210 located on the heater element 230 side is the second support plate 270 located on the bypass layer 250 side. It is smaller than the unevenness (strain). By reducing the structural strain on the heater element 230 side where thermal strain is likely to occur, the load applied to the entire heater plate due to the stress due to thermal strain can be suppressed.

FIG. 26A and FIG. 26B are schematic cross-sectional views showing an electrostatic chuck according to a modification of the present embodiment.
Fig.26 (a) is typical sectional drawing showing the electrostatic chuck concerning the modification of this embodiment. FIG. 26B is a schematic cross-sectional view showing the heater plate of this modification. FIG. 26A and FIG. 26B correspond to, for example, schematic cross-sectional views taken along the cutting plane A1-A1 illustrated in FIG.

  The electrostatic chuck 10a shown in FIG. 26A includes a ceramic dielectric substrate 100, a heater plate 200a, and a base plate 300. The ceramic dielectric substrate 100 and the base plate 300 are as described above with reference to FIGS.

  As shown in FIG. 26B, the heater plate 200a of this example has a plurality of heater elements. The heater plate 200a shown in FIG. 26B includes a first resin layer 220, a first heater element (heat generation layer) 230a, a second resin layer 240, and a second heater element (heat generation layer). 230 b, a third resin layer 260, a bypass layer 250, a fourth resin layer 290, and a second support plate 270.

  The first resin layer 220 is provided between the first support plate 210 and the second support plate 270. The first heater element 230 a is provided between the first resin layer 220 and the second support plate 270. The second resin layer 240 is provided between the first heater element 230 a and the second support plate 270. The second heater element 230 b is provided between the second resin layer 240 and the second support plate 270. The third resin layer 260 is provided between the second heater element 230 b and the second support plate 270. The bypass layer 250 is provided between the third resin layer 260 and the second support plate 270. The fourth resin layer 290 is provided between the bypass layer 250 and the second support plate 270. That is, in this specific example, the first heater element 230a is provided in a state independent of the second heater element 230b in a different layer.

  The respective materials of the first support plate 210, the first resin layer 220, the second resin layer 240, the third resin layer 260, the bypass layer 250, and the second support plate 270, The thickness and function are as described above with reference to FIGS. The materials, thicknesses, and functions of the first heater element 230a and the second heater element 230b are the same as those of the heater element 230 described above with reference to FIGS. The fourth resin layer 290 is the same as the first resin layer 220 described above with reference to FIGS.

  The heater plate 200a includes a resin portion 223 (not shown in FIG. 26) similarly to the heater plate 200 described with reference to FIG. Each resin part 223 is provided between two adjacent heater electrodes of the first heater element 230a and between two adjacent heater electrodes of the second heater element 230b.

  According to this modification, since the first heater element 230a is independently arranged in a layer different from the second heater element 230b, the temperature in the surface of the processing object W is independent for each predetermined region. Can be controlled.

FIG. 27A, FIG. 27B, and FIG. 28 are schematic plan views showing modifications of the first support plate of the present embodiment.
FIG. 29 is a schematic cross-sectional view showing a heater plate of this modification.
FIG. 27A shows an example in which the first support plate is divided into a plurality of support portions. FIG. 27B and FIG. 28 show another example in which the first support plate is divided into a plurality of support portions.

  In FIG. 29, for convenience of explanation, the heater plate shown in FIG. 27A and the graph of the temperature of the upper surface of the first support plate are shown together. The graph shown in FIG. 29 is an example of the temperature of the upper surface of the first support plate. The horizontal axis of the graph shown in FIG. 29 represents the position of the upper surface of the first support plate 210a. The vertical axis of the graph shown in FIG. 29 represents the temperature of the upper surface of the first support plate 210a. In FIG. 29, for convenience of explanation, the resin portion 223, the bypass layer 250, and the third resin layer 260 are omitted.

  In the modification shown in FIGS. 27A and 27B, the first support plate 210a is divided into a plurality of support portions. More specifically, in the modification shown in FIG. 27A, the first support plate 210a is concentrically divided into a plurality of support portions, and includes a first support portion 216 and a second support portion. 217, a third support portion 218, and a fourth support portion 219. In the modification shown in FIG. 27B, the first support plate 210b is concentrically and radially divided into a plurality of support portions, and includes a first support portion 216a, a second support portion 216b, 3 support part 216c, 4th support part 216d, 5th support part 216e, 6th support part 216f, 7th support part 217a, 8th support part 217b, and 9th It has a support part 217c, a tenth support part 217d, an eleventh support part 217e, and a twelfth support part 217f.

  In the modification shown in FIG. 28, the first support plate 210c has a larger number of support portions. In the first support plate 210c of FIG. 26, the first support portion 216 shown in FIG. 27A is further divided into four support portions 216a to 216d. In addition, the second support portion 217 shown in FIG. 27A is further divided into eight support portions 217a to 217h. Moreover, the 3rd support part 218 shown to Fig.27 (a) is further divided | segmented into eight area | region 218a-218h. And the 4th support part 219 shown in Drawing 27 (a) is further divided into 16 support parts 219a-219p. Thus, the number and shape of the support portions provided on the first support plate 210 may be arbitrary.

  The first resin layer 220, the heater element 230, the second resin layer 240, the bypass layer 250, the third resin layer 260, the second support plate 270, and the power supply terminal 280 are respectively 3 to 5 and 15 as described above.

  In the following description regarding FIG. 27A to FIG. 29, the first support plate 210a illustrated in FIG. As shown in FIG. 29, the first support portion 216 is provided on the first region 231 of the heater element 230 and corresponds to the first region 231 of the heater element 230. The second support portion 217 is provided on the second region 232 of the heater element 230 and corresponds to the second region 232 of the heater element 230. The third support portion 218 is provided on the third region 233 of the heater element 230 and corresponds to the third region 233 of the heater element 230. The fourth support portion 219 is provided on the fourth region 234 of the heater element 230 and corresponds to the fourth region 234 of the heater element 230.

  The first support part 216 is not electrically joined to the second support part 217. The second support part 217 is not electrically joined to the third support part 218. The third support part 218 is not electrically joined to the fourth support part 219.

  According to this modification, a temperature difference in the radial direction can be intentionally provided in the plane of the first support plates 210a, 210b, 210c (temperature controllability). For example, as shown in the graph shown in FIG. 29, a temperature difference can be provided in a step shape from the first support portion 216 to the fourth support portion 219. Thereby, a temperature difference can be intentionally provided in the surface of the processing object W (temperature controllability).

The structure of the heater plate 200 according to the present embodiment will be further described with reference to the drawings.
FIG. 30A to FIG. 30D are cross-sectional views showing a part of a modified example of the heater plate of the present embodiment.
FIG. 30A shows a part of the heater element 230, and FIG. 30B shows a part of the bypass layer 250. 30C shows a part of the heater element 230 and the bypass layer 250, and FIG. 30D shows a modification of the heater element 230 and the bypass layer 250.
As shown in FIG. 30A and FIG. 30C, each heater electrode 239 has a first surface P1 (upper surface) and a second surface P2 (lower surface). For example, the first conductive portion 21 has an upper surface 21U (first surface P1) and a lower surface 21L (second surface P2).

  The width W1 of the first surface P1 is different from the width W2 of the second surface P2. In this example, the width W1 of the first surface P1 is narrower than the width W2 of the second surface P2. That is, the width of the heater electrode 239 becomes narrower toward the upper side (the ceramic dielectric substrate 100 side).

  As shown in FIGS. 30B and 30C, the bypass portion 251 (bypass layer 250) includes a third conductive portion 23 and a fourth conductive portion 24. The fourth conductive portion 24 is separated from the third conductive portion 23 in the in-plane direction Dp (for example, the X direction). The third conductive portion 23 and the fourth conductive portion 24 are part of the bypass portion 251.

  Each bypass portion 251 has a third surface P3 (upper surface) and a fourth surface P4 (lower surface). The third surface P3 faces the second resin layer 240. The fourth surface P4 faces away from the third surface P3. That is, the fourth surface P4 faces the third resin layer 260.

  The width W3 of the third surface P3 is different from the width W4 of the fourth surface P4. In this example, the width W3 of the third surface P3 is narrower than the width W4 of the fourth surface P4. That is, the width of the bypass portion 251 becomes narrower toward the upper side (the ceramic dielectric substrate 100 side). In this example, the width relationship between the third surface P3 and the fourth surface P4 is the same as the width relationship between the first surface P1 and the second surface P2.

  Each bypass portion 251 has a pair of side surfaces SF2 that connect the third surface P3 and the fourth surface P4. Each side surface SF2 has, for example, a concave curved surface shape. Each side surface SF2 may be planar, for example. An angle θ3 formed by the third surface P3 and the side surface SF2 is different from an angle θ4 formed by the fourth surface P4 and the side surface SF2. Further, the surface roughness of the side surface SF2 is larger than the surface roughness of at least one of the third surface P3 and the fourth surface P4.

  The heater plate 200 further includes a resin portion 224. The resin part 224 is provided between the third conductive part 23 and the fourth conductive part 24. In other words, the resin part 224 is provided between each of the bypass parts 251. The resin part 224 is filled between the bypass parts 251. The material of the resin part 224 is different from the material of the second resin layer 240. The material of the resin part 224 is different from the material of the third resin layer 260. The composition of the resin part 224 is different from the composition of the second resin layer 240 and the third resin layer 260. The thermal history of the resin part 224 is different from the thermal history of the second resin layer 240 and the third resin layer 260. The physical properties (for example, melting point and glass transition point) of the resin portion 224 are different from the physical properties of the second resin layer 240 and the third resin layer 260.

  For example, when the resin part 224 includes a component different from the component included in the second resin layer 240, the material of the resin part 224 is different from the material of the second resin layer 240. Even when the resin part 224 includes the same component as the component of the second resin layer 240, the composition ratio (concentration) of the component in the resin part 224 is different from the composition ratio (concentration) of the component in the second resin layer 240. In this case, the material of the resin part 224 is different from the material of the second resin layer 240. Further, for example, even when the second resin layer 240 includes a plurality of layers, when the material of at least one of the plurality of layers is different from the material of the resin portion 224, the material of the resin portion 224 is the second Different from the material of the resin layer 240. For example, the glass transition point (or melting point) of the resin part 224 is lower than the glass transition point (or melting point) of the second resin layer 240. The same applies to the case where the material of the resin portion 224 and the material of the third resin layer 260 are different. For example, a polyimide film, a foaming adhesive sheet, an adhesive containing silicone or epoxy can be used.

  For the resin part 224, for example, polyimide, silicone, epoxy, acrylic, or the like is used. For example, a polyimide film, a foaming adhesive sheet, an adhesive containing silicone or epoxy can be used.

  The third surface P3 is in contact with the second resin layer 240, for example. For example, the fourth surface P4 is in contact with the third resin layer 260.

  In the electrostatic chuck 10, the width relationship between the third surface P3 and the fourth surface P4 is the same as the width relationship between the first surface P1 and the second surface P2. In the electrostatic chuck 10, the widths of the first surface P1 and the third surface P3 are narrower than the widths of the second surface P2 and the fourth surface P4. In this case, variation in heat distribution in the Z direction can be further suppressed.

  30A to 30C, the heater element 230 is provided on the bypass layer 250. For example, as shown in FIG. 30D, the bypass layer 250 may be provided on the heater element 230.

Fig.31 (a)-FIG.31 (d) is sectional drawing showing a part of modification of the heater plate of this embodiment.
As shown in FIGS. 31A and 31C, in this example, the width W1 of the first surface P1 is larger than the width W2 of the second surface P2. That is, the width of the heater electrode 239 becomes narrower toward the lower side (base plate 300 side). Similarly, as shown in FIGS. 31B and 31C, the width W3 of the third surface P3 is wider than the width W4 of the fourth surface P4. The width of the bypass portion 251 becomes narrower as it goes downward.

  In this example, the width relationship between the third surface P3 and the fourth surface P4 is the same as the width relationship between the first surface P1 and the second surface P2, and the widths of the first surface P1 and the third surface P3. However, it is wider than the width of the second surface P2 and the fourth surface P4. In this case, heat can be easily held on the first surface P1 and third surface P3 sides, and heat can be easily cooled on the second surface P2 and fourth surface P4 sides, so that temperature followability can be further improved. . Further, as shown in FIG. 31D, the bypass layer 250 may be provided on the heater element 230.

FIG. 32A to FIG. 32D are cross-sectional views showing a part of a modified example of the heater plate of the present embodiment.
As shown in FIGS. 32A and 32C, in this example, the width W1 of the first surface P1 is smaller than the width W2 of the second surface P2. On the other hand, as shown in FIGS. 32B and 32C, the width W3 of the third surface P3 is wider than the width W4 of the fourth surface P4. In this example, the width relationship between the third surface P3 and the fourth surface P4 is opposite to the width relationship between the first surface P1 and the second surface P2.

  As described above, the width relationship between the third surface P3 and the fourth surface P4 may be opposite to the width relationship between the first surface P1 and the second surface P2. In this case, the direction of the stress applied by the thermal expansion of the bypass layer 250 can be made opposite to the direction of the stress applied by the thermal expansion of the heater element 230. Thereby, the influence of stress can be suppressed more. Note that as shown in FIG. 32D, the bypass layer 250 may be provided on the heater element 230.

FIG. 33A to FIG. 33D are cross-sectional views showing a part of a modification of the heater plate of the present embodiment.
As shown in FIGS. 33A to 33C, the width W1 of the first surface P1 is made larger than the width W2 of the second surface P2, and the width W3 of the third surface P3 is set to be the fourth surface P4. It may be narrower than the width W4. Further, as shown in FIG. 33 (d), the bypass layer 250 may be provided on the heater element 230.

FIG. 34A and FIG. 34B are explanatory diagrams illustrating an example of a simulation result of the heater plate.
FIG. 34A shows a part of the heater pattern of the heater electrode 239 used in the simulation. FIG. 34B is a cross-sectional view illustrating an example of a simulation result.
In the simulation, CAE (Computer Aided Engineering) analysis was performed on the amount of heat generated when a current was passed through the heater electrode 239 shown in FIG. In FIG. 34 (b), the analysis result of the calorific value is represented by shaded shades. In FIG. 34 (b), the shaded light and shaded portion indicates a low temperature portion, and the temperature increases as the concentration increases.

  In the simulation, CAE analysis was performed on a hot spot HSP that tends to have a high temperature in the heater electrode 239. FIG. 34B shows a cross section of the hot spot HSP taken along line G1-G2. In the simulation model, the bypass layer 250 is provided between the ceramic dielectric substrate 100 and the heater element 230. In addition, the first resin layer 220, the second resin layer 240, and the third resin layer 260 are collectively illustrated as one layer (polyimide layer) for convenience. In the simulation, the width of the heater electrode 239 is constant. That is, in the simulation, the width W1 of the first surface P1 is substantially the same as the width W2 of the second surface P2.

  The hot spot HSP is located on the outermost periphery of the substantially circular heater plate 200. The hot spot HSP is a portion where the curvature is reversed from the other portions. In the hot spot HSP, the inner part of the arc faces the outer peripheral side of the heater plate 200.

  In the heater electrode 239 curved in an arc shape, the path is shorter on the inner side and the resistance is lower than the outer side. For this reason, in the arc-shaped heater electrode 239, the inner side has a higher current density and the higher temperature than the outer side. Therefore, as shown in FIG. 34B, in the hot spot HSP, the temperature on the outer peripheral side of the heater plate 200 inside the arc is higher than that on the center side. Further, in the hot spot HSP, the curvature is inverted from that of the other portions, so that a current flows relatively easily through a portion having a large diameter on the center side. For this reason, the temperature of the hot spot HSP is likely to rise as compared with other portions.

  Thus, in the heater electrode 239 curved in an arc shape, the temperature distribution is uneven between the inner part and the outer part. Due to such uneven temperature distribution, thermal distortion occurs in the heater electrode 239. At this time, for example, by providing a space portion at the side end portion of the first conductive portion 21, stress applied to the first resin layer 220 and the second resin layer 240 due to such thermal strain can be reduced.

  In addition, as shown in FIG. 34B, in the heater electrode 239, the temperature on the ceramic dielectric substrate 100 side (upper side) tends to be higher than that on the base plate 300 side (lower side). This is because heat escapes to the base plate 300 side. For example, in the case where a high temperature portion is locally generated immediately above the heater electrode 239, the width W1 of the first surface P1 is set to be equal to that of the second surface P2, as shown in FIG. It is narrower than the width W2. Thereby, as described above, variation in the heat distribution in the Z direction can be suppressed. For example, it is possible to suppress the local occurrence of a portion having a high temperature immediately above the heater electrode 239, and to improve the heat uniformity.

FIG. 35A and FIG. 35B are schematic plan views illustrating specific examples of the power supply terminal of the present embodiment.
FIG. 35A is a schematic plan view showing a power supply terminal of this example. FIG. 35B is a schematic plan view illustrating the method for joining the power supply terminals according to this example.

  A power supply terminal 280 illustrated in FIGS. 35A and 35B includes a pin portion 281, a conductive wire portion 283, a support portion 285, and a joint portion 287. The pin portion 281 is connected to a member called a socket or the like. The socket supplies power from the outside of the electrostatic chuck 10. The conducting wire part 283 is connected to the pin part 281 and the support part 285. The support portion 285 is connected to the conductor portion 283 and the joint portion 287. The joining portion 287 is joined to the heater element 230 or the bypass layer 250 as indicated by an arrow C14 shown in FIG.

  The conductor portion 283 relieves stress applied to the power supply terminal 280. That is, the pin portion 281 is fixed to the base plate 300. On the other hand, the joint portion 287 is joined to the heater element 230 or the bypass layer 250. A temperature difference is generated between the base plate 300 and the heater element 230 or the bypass layer 250. Therefore, a difference in thermal expansion occurs between the base plate 300 and the heater element 230 or the bypass layer 250. Therefore, stress due to a difference in thermal expansion may be applied to the power supply terminal 280. The stress resulting from the difference in thermal expansion is applied in the radial direction of the base plate 300, for example. The conductor portion 283 can relieve this stress. The joining portion 287 and the heater element 230 or the bypass layer 250 are joined by welding, joining using laser light, soldering, brazing, or the like.

  Examples of the material of the pin portion 281 include molybdenum. Examples of the material of the conductive wire portion 283 include copper. The diameter D5 of the conducting wire part 283 is smaller than the diameter D8 of the pin part 281. The diameter D5 of the conducting wire part 283 is, for example, about 0.3 mm or more and 2.0 mm or less. Examples of the material of the support portion 285 include stainless steel. The thickness D6 (length in the Z direction) of the support portion 285 is, for example, about 0.5 mm or more and 2.0 mm or less. Examples of the material of the bonding portion 287 include stainless steel. A thickness D7 (length in the Z direction) of the joint portion 287 is, for example, about 0.05 mm or more and 0.50 mm or less.

  According to this specific example, since the diameter D8 of the pin portion 281 is larger than the diameter D5 of the conducting wire portion 283, the pin portion 281 can supply a relatively large current to the heater element 230. Moreover, since the diameter D5 of the conducting wire part 283 is smaller than the diameter D8 of the pin part 281, the conducting wire part 283 is easier to deform than the pin part 281, and the position of the pin part 281 can be shifted from the center of the joint part 287. . Thereby, the power supply terminal 280 can be fixed to a member (for example, the base plate 300) different from the heater plate 200.

  The support portion 285 is joined to the conductor portion 283 and the joint portion 287 by, for example, welding, joining using laser light, soldering, brazing, or the like. Thereby, a wider contact area with respect to the heater element 230 or the bypass layer 250 can be ensured while relaxing the stress applied to the power supply terminal 280.

FIG. 36 is a schematic exploded view showing a modification of the heater plate of the present embodiment.
As shown in FIG. 36, in this example, the bypass layer 250 is provided between the first support plate 210 and the heater element 230. More specifically, the bypass layer 250 is provided between the first support plate 210 and the first resin layer 220, and the third resin layer 260 is provided between the first support plate 210 and the bypass layer 250. Is provided.

  As described above, the bypass layer 250 may be provided between the first support plate 210 and the heater element 230. That is, the bypass layer 250 may be provided between the heater element 230 and the ceramic dielectric substrate 100.

  Even in this case, the diffusibility of the heat supplied from the heater element 230 can be improved by the bypass layer 250. For example, the thermal diffusibility in the in-plane direction (horizontal direction) of the processing target W can be improved. Thereby, the uniformity of the temperature distribution in the surface of the process target W can be improved, for example.

  Note that the bypass layer 250 may be provided, for example, both between the first support plate 210 and the heater element 230 and between the heater element 230 and the second support plate 270. That is, the heater plate 200 includes two bypass layers 250 provided between the first support plate 210 and the heater element 230 and between the heater element 230 and the second support plate 270, respectively. May be.

FIG. 37 is a schematic cross-sectional view illustrating a modification of the power feeding terminal of the present embodiment.
In this example, the electrostatic chuck according to the embodiment includes a power supply terminal 280a instead of the power supply terminal 280 described above. The power supply terminal 280a includes a power supply unit (main body unit) 281a and a terminal unit 281b. The power supply terminal 280a is, for example, a contact probe.

  For example, the hole 390 is provided in the base plate 300. The cylindrical sleeve 283a is fixed to the hole 390. The power supply terminal 280a is provided inside the sleeve 283a, and is fixed to the base plate 300 by, for example, screwing.

A socket 285a that supplies power to the heater element 230 from the outside can be connected to the power supply unit 281a.
The terminal portion 281b is provided at the tip of the power supply terminal 280a and contacts the heater element 230 or the bypass layer 250. The terminal portion 281b is slidable with respect to the power feeding portion 281a, and the power feeding terminal 280a can be expanded and contracted. In addition, the power supply terminal 280a has a spring fixed to the power supply unit 281a inside. The terminal portion 281b is biased by the spring so that the power supply terminal 280a extends.

  The terminal portion 281b is pressed against the heater plate 200 (the heater element 230 or the bypass layer 250). At this time, the power supply terminal 280a is in a contracted state against the elastic force of the spring. In other words, the terminal portion 281b is urged and pressed in the direction toward the heater element 230 or the bypass layer 250 by the elastic force of the spring. As a result, the socket 285a is electrically connected to the heater element 230 or the bypass layer 250 via the power supply terminal 280a. Electric power is supplied to the heater element 230 or the bypass layer 250 from the outside through the power supply terminal 280a and the socket 285a.

  When such a power supply terminal 280a is used, compared to the case where the power supply terminals are joined by welding or the like, holes provided for power supply (holes 390 in the base plate 300 and holes 273 in the second support plate 270) are provided. The diameter can be reduced.

FIG. 38 is a schematic sectional view showing a wafer processing apparatus according to another embodiment of the present invention.
A wafer processing apparatus 500 according to this embodiment includes a processing container 501, an upper electrode 510, and the electrostatic chuck (for example, the electrostatic chuck 10) described above with reference to FIGS. A processing gas inlet 502 for introducing processing gas into the inside is provided on the ceiling of the processing container 501. The bottom plate of the processing vessel 501 is provided with an exhaust port 503 for exhausting the inside under reduced pressure. Further, a high frequency power source 504 is connected to the upper electrode 510 and the electrostatic chuck 10 so that a pair of electrodes having the upper electrode 510 and the electrostatic chuck 10 face each other in parallel at a predetermined interval. Yes.

  In the wafer processing apparatus 500 according to the present embodiment, when a high frequency voltage is applied between the upper electrode 510 and the electrostatic chuck 10, a high frequency discharge occurs and the processing gas introduced into the processing container 501 is excited by plasma, It is activated and the processing object W is processed. An example of the processing object W is a semiconductor substrate (wafer). However, the processing object W is not limited to a semiconductor substrate (wafer), and may be, for example, a glass substrate used in a liquid crystal display device.

  The high frequency power source 504 is electrically connected to the base plate 300 of the electrostatic chuck 10. As described above, a metal material such as aluminum is used for the base plate 300. That is, the base plate 300 has conductivity. As a result, the high frequency voltage is applied between the upper electrode 410 and the base plate 300.

  In the wafer processing apparatus 500 of this example, the base plate 300 is electrically connected to the first support plate 210 and the second support plate 270. As a result, in the wafer processing apparatus 500, a high frequency voltage is also applied between the first support plate 210 and the upper electrode 510 and between the second support plate 270 and the upper electrode 510.

  In this way, a high frequency voltage is applied between the support plates 210 and 270 and the upper electrode 510. Thereby, compared with the case where a high frequency voltage is applied only between the base plate 300 and the upper electrode 510, the place where the high frequency voltage is applied can be brought closer to the processing object W. Thereby, for example, plasma can be generated more efficiently and at a low potential.

  An apparatus having a configuration such as the wafer processing apparatus 500 is generally called a parallel plate RIE (Reactive Ion Etching) apparatus, but the electrostatic chuck 10 according to the present embodiment is not limited to application to this apparatus. . For example, so-called decompression processing equipment such as ECR (Electron Cyclotron Resonance) etching equipment, dielectric coupled plasma processing equipment, helicon wave plasma processing equipment, plasma separation type plasma processing equipment, surface wave plasma processing equipment, plasma CVD (Chemical Vapor Deposition) equipment, etc. Can be widely applied to. Further, the electrostatic chuck 10 according to the present embodiment can be widely applied to a substrate processing apparatus that performs processing and inspection under atmospheric pressure, such as an exposure apparatus and an inspection apparatus. However, considering the high plasma resistance of the electrostatic chuck 10 according to the present embodiment, it is preferable to apply the electrostatic chuck 10 to the plasma processing apparatus. In addition, since a well-known structure is applicable to parts other than the electrostatic chuck 10 concerning this embodiment among the structures of these apparatuses, the description is abbreviate | omitted.

FIG. 39 is a schematic cross-sectional view showing a modification of the wafer processing apparatus according to another embodiment of the present invention.
As shown in FIG. 39, the high frequency power source 504 is electrically connected only between the first support plate 210 and the upper electrode 510 and between the second support plate 270 and the upper electrode 510. Also good. Also in this case, the place where the high frequency voltage is applied can be brought close to the processing object W, and plasma can be generated efficiently.

FIG. 40 is a schematic cross-sectional view showing a modification of the wafer processing apparatus according to another embodiment of the present invention.
As shown in FIG. 40, in this example, the high frequency power source 504 is electrically connected to the heater element 230. As described above, the high frequency voltage may be applied between the heater element 230 and the upper electrode 510. Also in this case, the place where the high frequency voltage is applied can be brought close to the processing object W, and plasma can be generated efficiently.

  The high frequency power supply 504 is electrically connected to the heater element 230 via each power supply terminal 280, for example. For example, the high frequency voltage is selectively applied to a plurality of regions (for example, the first region 231 to the fourth region 234 shown in FIG. 21A) of the heater element 230. Thereby, the distribution of the high frequency voltage can be controlled.

  The high frequency power source 504 may be electrically connected to the first support plate 210, the second support plate 270, and the heater element 230, for example. The high frequency voltage is applied between the first support plate 210 and the upper electrode 510, between the second support plate 270 and the upper electrode 510, and between the heater element 230 and the upper electrode 510. Also good.

The embodiment of the present invention has been described above. However, the present invention is not limited to these descriptions. As long as the features of the present invention are provided, those skilled in the art appropriately modified the design of the above-described embodiments are also included in the scope of the present invention. For example, the shape, size, material, arrangement, etc. of each element provided in the heater plates 200, 200a, 200b, etc., the installation form of the heater element 230, the first heater element 230a, the second heater element 230b, and the bypass layer 250, etc. Are not limited to those illustrated, but can be changed as appropriate.
Moreover, each element with which each embodiment mentioned above is provided can be combined as long as technically possible, and the combination of these is also included in the scope of the present invention as long as it includes the features of the present invention.

  DESCRIPTION OF SYMBOLS 10 electrostatic chuck, 10a electrostatic chuck, 21 1st electroconductive part, 21L lower surface, 21U upper surface, 21a side edge part, 21b side edge part, 22 2nd electrically conductive part, 22a side edge part, 23 3rd electric conduction Part, 23a space part, 23b space part, 23c space part, 24 fourth conductive part, 25h joint part, 100 ceramic dielectric substrate, 101 first principal surface, 102 second principal surface, 107 first dielectric layer, 109 Second dielectric layer, 111 electrode layer, 113 convex portion, 115 groove, 200, 200a heater plate, 201 lift pin hole, 203 center, 210, 210a, 210b, 210c first support plate, 211 surface, 211a concave portion, 211b convex Part, 213 surface, 213a concave part, 213b convex part, 216 first support part, 216a first support part, 2 16b 2nd support part, 216c 3rd support part, 216d 4th support part, 216e 5th support part, 216f 6th support part, 217 2nd support part, 217a 7th support part, 217b 8th support part, 217c 9th support part, 217d 10th support part, 217e 11th support part, 217f 12th support part, 218 3rd support part, 219 4th support part, 220th 1 resin layer, 221 first resin portion, 221a, 221b side end portion, 222 second resin portion, 222a side end portion, 223, 224 resin portion, 230, 230a, 230b heater element, 231 first region 231a first region, 231b second region, 231c third region, 231d fourth region, 231e fifth region, 231f sixth region, 232 2nd region, 232a 7th region, 232b 8th region, 232c 9th region, 232d 10th region, 232e 11th region, 232f 12th region, 233 3rd region, 234 1st 4 region, 235 spaced part, 239 heater electrode, 240 second resin layer, 241 hole, 250 bypass layer, 251 bypass part, 251a surface, 253 notch part, 255a, 255b, 255c, 255d, 255e, 255f, 255g, 255h bonding portion, 257 separation portion, 259 center, 260 third resin layer, 261 hole, 270 support plate, 271 surface, 271a recess, 271b protrusion, 273 hole, 275 surface, 275a recess, 275b protrusion, 280, 280a Power supply terminal, 290 Fourth resin layer, 3 0 base plate, 301 communication path, 303 lower surface, 321 introduction path, 403 adhesive, 500 wafer processing apparatus, Cp1 center, Ep1, Ep2 end, HSP hot spot, P1-P4 first to fourth surfaces, Pt1-Pt4 Vertex, S1, S2 side surface, SP1-SP4 1st-4th support part, W processing target object

According to a first aspect of the present invention, there is provided a ceramic dielectric substrate on which an object to be processed is placed, a base plate provided at a position separated from the ceramic dielectric substrate in the stacking direction, and supporting the ceramic dielectric substrate, and the ceramic dielectric A heater plate provided between a substrate and the base plate, wherein the heater plate is provided between the ceramic dielectric substrate and the base plate, and includes a first support plate including metal, and the first plate. A second support plate including a metal provided between the support plate and the base plate, a first resin layer provided between the first support plate and the second support plate, A second resin layer provided between the first resin layer and the second support plate; a resin portion provided between the first resin layer and the second resin layer; Before the first resin layer A first conductive portion provided between the second resin layer and a second conductive portion spaced from the first conductive portion in an in-plane direction perpendicular to the stacking direction; , A heater element that generates heat when a current flows, a first side end portion in the in-plane direction of the first conductive portion, the first resin layer, the second resin layer, and the resin And a first space portion partitioned by the first resin layer, wherein the first resin layer is disposed between the first conductive portion and the second conductive portion. The first support plate is aligned with the first conductive portion in the stacking direction, and the first space portion in the stacking direction. A second support portion arranged side by side, wherein the second support plate is aligned with the first conductive portion in the stacking direction. 3 and a fourth support part aligned with the first space part in the stacking direction, and the distance between the second support part and the fourth support part is the first support part. The electrostatic chuck is shorter than a distance between one support portion and the third support portion .

According to this electrostatic chuck, the first space (gap) is provided at the end of the first conductive portion of the heater element. Even if the heater element is thermally expanded, the first conductive portion is deformed so as to fill the first space portion. For this reason, when a heater element deform | transforms by thermal expansion, the stress concerning a 1st resin layer and a 2nd resin layer can be reduced. Therefore, peeling between the heater element and the first resin layer and peeling between the heater element and the second resin layer can be suppressed. Therefore, the resistance to the load is high and the reliability can be improved. It is possible to suppress the temperature change of the processing object caused by the peeling.
Moreover, according to this electrostatic chuck, unevenness is formed on at least one of the first support plate and the second support plate. Such unevenness is formed by high adhesion between the heater element (first conductive portion) and a member sandwiching the heater element. Due to the high adhesion, it is possible to achieve the thermal uniformity and withstand voltage characteristics as designed. Moreover, the distance between a heater element and a process target object can be shortened by forming a convex part in the 1st support plate. Thereby, the speed which raises the temperature of a process target object can be improved. Therefore, it is possible to achieve both “heating performance (heating rate) of the heater”, “temperature uniformity”, and “withstand voltage reliability”.

According to a seventh invention, in the first to sixth any one invention, the area of a portion of the first support plate is joined to a portion of the second support plate regions, said first An electrostatic chuck characterized in that it is narrower than the area of the upper surface of the support plate and smaller than the area of the lower surface of the second support plate.

A ninth invention is the electrostatic chuck according to any one of the first to eighth inventions, wherein a thickness of the first resin layer is equal to or less than a thickness of the first conductive portion. .

A nineteenth aspect of the invention is characterized in that, in any one of the first to eighteenth aspects, a conductive bypass layer is further provided between the heater element and the second support plate. Electrostatic chuck.

Invention of the second zero, the at 19 invention, the magnitude relation of the width of the lower surface of the bypass layer to the width of the upper surface of the bypass layer, the first conductive portion to the first width of the upper surface of the conductive portion The electrostatic chuck is characterized in that it has the same size relationship as the width of the lower surface of the electrostatic chuck.

In a twenty- first aspect based on the nineteenth aspect , the relationship of the width of the lower surface of the bypass layer with respect to the width of the upper surface of the bypass layer is such that the first conductive portion relative to the width of the upper surface of the first conductive portion. The electrostatic chuck is opposite to the width relationship of the lower surface of the electrostatic chuck.

According to a twenty-second aspect of the present invention, there is provided a ceramic dielectric substrate on which an object to be processed is placed, a base plate provided at a position separated from the ceramic dielectric substrate in the stacking direction and supporting the ceramic dielectric substrate, and the ceramic dielectric A heater plate provided between a substrate and the base plate, and a bypass layer, and the heater plate is provided between the ceramic dielectric substrate and the base plate and includes a first support plate containing metal. , A second support plate provided between the first support plate and the base plate and containing metal, and a first resin provided between the first support plate and the second support plate Layer, a second resin layer provided between the first resin layer and the second support plate, and provided between the first resin layer and the second resin layer. A resin part; A second conductive layer provided between the first resin layer and the second resin layer and spaced apart from the first conductive portion in an in-plane direction perpendicular to the stacking direction; A heater element that generates heat when current flows, a first side end portion in the in-plane direction of the first conductive portion, the first resin layer, and the second resin layer. A first space part partitioned by a resin layer and the resin part, and the first resin layer is between the first conductive part and the second conductive part. The bypass layer is in contact with the second resin layer via the resin portion, and the bypass layer is provided between the heater element and the second support plate and has conductivity, and the bypass layer The relationship between the width of the lower surface of the bypass layer and the width of the upper surface of That is an electrostatic chuck, wherein the is the same as the first magnitude relationship of the lower surface of the width of the conductive portion.
According to this electrostatic chuck, the first space (gap) is provided at the end of the first conductive portion of the heater element. Even if the heater element is thermally expanded, the first conductive portion is deformed so as to fill the first space portion. For this reason, when a heater element deform | transforms by thermal expansion, the stress concerning a 1st resin layer and a 2nd resin layer can be reduced. Therefore, peeling between the heater element and the first resin layer and peeling between the heater element and the second resin layer can be suppressed. Therefore, the resistance to the load is high and the reliability can be improved. It is possible to suppress the temperature change of the processing object caused by the peeling. Further, in each of the bypass layer and the heater element (first conductive portion), when the upper surface is wider than the lower surface, the upper portion of the heater plate can be easily heated.
Further, since the lower surface is relatively short, the lower part of the heater plate can be easily cooled. Thereby, temperature followability (ramp plate) can be improved. In each of the bypass layer and the first conductive portion, when the lower surface is wider than the upper surface, it is possible to suppress the deviation of the heat distribution in the vertical direction.
According to a twenty-third aspect of the present invention, there is provided a ceramic dielectric substrate on which an object to be processed is placed, a base plate provided at a position separated from the ceramic dielectric substrate in the stacking direction and supporting the ceramic dielectric substrate, and the ceramic dielectric A heater plate provided between a substrate and the base plate, and a bypass layer, and the heater plate is provided between the ceramic dielectric substrate and the base plate and includes a first support plate containing metal. , A second support plate provided between the first support plate and the base plate and containing metal, and a first resin provided between the first support plate and the second support plate Layer, a second resin layer provided between the first resin layer and the second support plate, and provided between the first resin layer and the second resin layer. A resin part; A second conductive layer provided between the first resin layer and the second resin layer and spaced apart from the first conductive portion in an in-plane direction perpendicular to the stacking direction; A heater element that generates heat when current flows, a first side end portion in the in-plane direction of the first conductive portion, the first resin layer, and the second resin layer. A first space part partitioned by a resin layer and the resin part, and the first resin layer is between the first conductive part and the second conductive part. The bypass layer is in contact with the second resin layer via the resin portion, and the bypass layer is provided between the heater element and the second support plate and has conductivity, and the bypass layer The relationship between the width of the lower surface of the bypass layer and the width of the upper surface of That is an electrostatic chuck, wherein the is opposite to the first magnitude relationship of the lower surface of the width of the conductive portion.
According to this electrostatic chuck, the first space (gap) is provided at the end of the first conductive portion of the heater element. Even if the heater element is thermally expanded, the first conductive portion is deformed so as to fill the first space portion. For this reason, when a heater element deform | transforms by thermal expansion, the stress concerning a 1st resin layer and a 2nd resin layer can be reduced. Therefore, peeling between the heater element and the first resin layer and peeling between the heater element and the second resin layer can be suppressed. Therefore, the resistance to the load is high and the reliability can be improved. It is possible to suppress the temperature change of the processing object caused by the peeling. Further, in each of the bypass layer and the heater element (first conductive portion), when the upper surface is wider than the lower surface, the upper portion of the heater plate can be easily heated.
Further, the direction of the stress applied by the thermal expansion of the bypass layer can be opposite to the direction of the stress applied by the thermal expansion of the heater element. Thereby, the influence of stress can be suppressed more.
In a twenty-fourth aspect based on the twenty-second or twenty-third aspect, the first support plate includes a first support portion aligned with the first conductive portion in the stacking direction, and the first space in the stacking direction. A second support plate that is aligned with the first conductive portion in the stacking direction, and a second support plate that is aligned with the first conductive portion in the stacking direction and the first space portion in the stacking direction. And a distance between the second support portion and the fourth support portion is a distance between the first support portion and the third support portion. The electrostatic chuck is substantially the same as the above.
According to this electrostatic chuck, unevenness is not formed on the first support plate and the second support plate, or the unevenness is very small. The first support plate and the second support plate are, for example, flat. As a result, variations in the thickness of the adhesive that joins the heater plate, the ceramic dielectric substrate, and the base plate can be reduced, and in-plane heat transfer can be made uniform.
Further, the distance between the heater element and the object to be processed is reduced over the entire surface, and the speed at which the temperature of the object to be processed is increased can be improved. Therefore, it is possible to achieve both “heater heating performance (temperature increase rate)” and “temperature uniformity”.
According to a twenty- fifth aspect of the present invention, in any one of the nineteenth to twenty- fourth aspects, the heater element is electrically connected to the bypass layer, and the heater element and the bypass layer are connected to the first support plate. And an electrostatic chuck that is insulated from the second support plate.

According to a twenty- sixth aspect of the invention, in any one of the first to twenty- fifth aspects, an area of an upper surface of the first support plate is larger than an area of a lower surface of the second support plate. It is an electrostatic chuck.

A twenty- seventh aspect of the invention is characterized in that, in any one of the first to twenty- sixth aspects, the apparatus further includes a power supply terminal that is provided from the heater plate toward the base plate and supplies electric power to the heater plate. Electrostatic chuck.

In a twenty- eighth aspect based on the twenty- seventh aspect , the power supply terminal is connected to a pin portion connected to a socket for supplying power from the outside, a conductive wire portion thinner than the pin portion, and the conductive wire portion. An electrostatic chuck comprising: a support portion; and a joint portion connected to the support portion and joined to the heater element.

A twenty- ninth aspect of the invention is the electronic device according to any one of the nineteenth to twenty- fifth aspects, further comprising a power supply terminal that is provided from the heater plate toward the base plate and that supplies power to the heater plate. A pin part connected to a socket for supplying electric power from the outside, a conductive wire part thinner than the pin part, a support part connected to the conductive wire part, and connected to the support part and joined to the bypass layer An electrostatic chuck, wherein the electric power is supplied to the heater element through the bypass layer.

30th aspect, in the first to any one of the invention of the second 6, provided in the base plate, further comprising a power supply terminal for supplying power to the heater plate, the power supply terminal, supply of the electric power from the outside An electrostatic chuck comprising: a power supply unit connected to a socket to be connected; and a terminal unit connected to the power supply unit and pressed against the heater plate.

Claims (29)

A ceramic dielectric substrate on which an object to be treated is placed;
A base plate provided at a position away from the ceramic dielectric substrate in the stacking direction and supporting the ceramic dielectric substrate;
A heater plate provided between the ceramic dielectric substrate and the base plate;
With
The heater plate is
A first support plate provided between the ceramic dielectric substrate and the base plate and including a metal;
A second support plate provided between the first support plate and the base plate and containing metal;
A first resin layer provided between the first support plate and the second support plate;
A second resin layer provided between the first resin layer and the second support plate;
A resin portion provided between the first resin layer and the second resin layer;
A second conductive layer provided between the first resin layer and the second resin layer and spaced apart from the first conductive portion in the in-plane direction perpendicular to the stacking direction; And a heater element that generates heat when a current flows,
The first space portion defined by the first side end portion in the in-plane direction of the first conductive portion, the first resin layer, the second resin layer, and the resin portion. When,
Have
The first resin layer is in contact with the second resin layer via the resin portion between the first conductive portion and the second conductive portion. Chuck. The first conductive portion has a second side end portion spaced from the first side end portion in the in-plane direction,
2. The electrostatic device according to claim 1, wherein the heater plate has a second space portion defined by at least the second side end portion, the first resin layer, and the second resin layer. Chuck.   3. The electrostatic according to claim 1, wherein a length of the first space portion along the stacking direction is equal to or shorter than a length of the first conductive portion along the stacking direction. Chuck.   The first resin layer is separated from the second resin layer between the first conductive portion and the resin portion, according to any one of claims 1 to 3. Electrostatic chuck.   5. The electrostatic chuck according to claim 1, wherein the first space portion has four vertices in a cross section parallel to the stacking direction.   The electrostatic chuck according to claim 1, wherein the first support plate is electrically joined to the second support plate.   The area of the region where the first support plate is joined to the second support plate is narrower than the area of the upper surface of the first support plate and smaller than the area of the lower surface of the second support plate. The electrostatic chuck according to any one of claims 1 to 6, wherein:   The electrostatic chuck according to claim 1, wherein the resin portion includes a material different from a material of the first resin layer.   The electrostatic chuck according to claim 1, wherein a thickness of the first resin layer is equal to or less than a thickness of the first conductive portion. The first space portion is
A central portion in the in-plane direction;
An end in the in-plane direction;
Including
10. The electrostatic chuck according to claim 1, wherein a width of the central portion along the stacking direction is narrower than a width of the end portion along the stacking direction.   The length along the in-plane direction of the upper surface of the first conductive portion is different from the length along the in-plane direction of the lower surface of the first conductive portion. The electrostatic chuck according to any one of the above.   The length of the lower surface of the first conductive portion along the in-plane direction is longer than the length of the upper surface of the first conductive portion along the in-plane direction. The electrostatic chuck described.   The length of the upper surface of the first conductive portion along the in-plane direction is longer than the length of the lower surface of the first conductive portion along the in-plane direction. The electrostatic chuck described.   The electrostatic chuck according to claim 1, wherein a side surface of the first conductive portion is curved in a cross section parallel to the stacking direction.   The angle between the upper surface of the first conductive part and the side surface of the first conductive part is different from the angle between the lower surface of the first conductive part and the side surface of the first conductive part. The electrostatic chuck according to claim 1, wherein the electrostatic chuck is characterized in that:   The side surface of the first conductive part is rougher than at least one of the upper surface of the first conductive part and the lower surface of the first conductive part. The electrostatic chuck described. The heater element has a belt-like heater electrode,
The electrostatic chuck according to claim 1, wherein the heater electrodes are provided in a plurality of regions in an independent state. A plurality of the heater elements are provided,
The electrostatic chuck according to claim 1, wherein the plurality of heater elements are provided in different states in different layers. The first support plate is
A first support portion aligned with the first conductive portion in the stacking direction;
A second support part aligned with the first space part in the stacking direction;
Including
The second support plate is
A third support part aligned with the first conductive part in the stacking direction;
A fourth support part aligned with the first space part in the stacking direction;
Including
The distance between the second support part and the fourth support part is shorter than the distance between the first support part and the third support part. The electrostatic chuck according to any one of 18. The first support plate is
A first support portion aligned with the first conductive portion in the stacking direction;
A second support part aligned with the first space part in the stacking direction;
Including
The second support plate is
A third support part aligned with the first conductive part in the stacking direction;
A fourth support part aligned with the first space part in the stacking direction;
Including
The distance between the second support part and the fourth support part is substantially the same as the distance between the first support part and the third support part. The electrostatic chuck according to claim 1.   The electrostatic chuck according to claim 1, further comprising a conductive bypass layer provided between the heater element and the second support plate.   The relationship of the width of the lower surface of the bypass layer with respect to the width of the upper surface of the bypass layer is the same as the relationship of the width of the lower surface of the first conductive portion with respect to the width of the upper surface of the first conductive portion. The electrostatic chuck according to claim 21, wherein:   The magnitude relationship of the width of the lower surface of the bypass layer with respect to the width of the upper surface of the bypass layer is opposite to the relationship of the width of the lower surface of the first conductive portion with respect to the width of the upper surface of the first conductive portion. The electrostatic chuck according to claim 21, wherein: The heater element is electrically connected to the bypass layer;
24. The electrostatic chuck according to claim 21, wherein the heater element and the bypass layer are insulated from the first support plate and the second support plate.   The electrostatic chuck according to claim 1, wherein an area of an upper surface of the first support plate is larger than an area of a lower surface of the second support plate.   The electrostatic chuck according to claim 1, further comprising a power supply terminal that is provided from the heater plate toward the base plate and supplies electric power to the heater plate. The power supply terminal is
A pin connected to a socket for supplying power from the outside;
A conducting wire part thinner than the pin part;
A support portion connected to the conductor portion;
A joint portion connected to the support portion and joined to the heater element;
27. The electrostatic chuck according to claim 26, comprising: A power supply terminal provided from the heater plate toward the base plate and supplying power to the heater plate;
The power supply terminal is
A pin connected to a socket for supplying power from the outside;
A conducting wire part thinner than the pin part;
A support portion connected to the conductor portion;
A joint connected to the support and joined to the bypass layer;
The electrostatic chuck according to claim 21, wherein the electric power is supplied to the heater element through the bypass layer. A power supply terminal provided on the base plate and configured to supply power to the heater plate;
The power supply terminal is
A power feeding unit connected to a socket for supplying power from the outside;
A terminal portion connected to the power feeding portion and pressed against the heater plate;
The electrostatic chuck according to claim 1, comprising: