Electrostatic chuck part and electrostatic chuck device

Abstract

An electrostatic chuck member is provided with: a plate-shaped dielectric substrate provided with a placement surface on which a plate-shaped sample is placed and an air hole penetrating in the thickness direction; an adsorption electrode disposed inside the dielectric substrate; a bias electrode disposed inside the dielectric substrate; and an electrically conductive discharge suppression member embedded in the dielectric substrate so as to surround the air hole, the discharge suppression member being provided electrically independently.

Description

Technical Field

[0001] This invention relates to an electrostatic chuck component and an electrostatic chuck device.

[0002] This application claims priority based on Japanese Patent Application No. 2023-158380, filed on September 22, 2023, the contents of which are incorporated herein by reference. Background Technology

[0003] Electrostatic chuck devices for supporting substrates such as semiconductor wafers are known. For example, in Patent Document 1, such an electrostatic chuck device is described as having a structure with multiple pores in a sample stage that electrostatically adsorbs the object to be processed. These pores are used to supply a heat-conducting gas for controlling the temperature of the object to be processed between the object to be processed and the sample stage.

[0004] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2010-182763 Summary of the Invention The technical problem to be solved by the invention In the electrostatic chuck apparatus described above, the through-hole for gas supply can sometimes become the starting point for discharges that damage semiconductor wafers. In recent years, with the multilayer stacking of semiconductors, high-power processing for deep holes is underway in plasma etching equipment for semiconductor manufacturing. Therefore, it is necessary to suppress the generation of abnormal discharges inside the pores.

[0005] One of the objectives of this invention is to provide an electrostatic chuck device capable of suppressing abnormal discharges inside pores.

[0006] means for solving technical problems This invention includes the inventions described below [1] to [6].

[0007] The following inventions are also preferably combined in two or more as needed.

[0008] [1] An electrostatic chuck component comprising: a dielectric substrate having a mounting surface for mounting a plate-shaped sample and pores penetrating along the thickness direction, and being plate-shaped; an adsorption electrode disposed inside the dielectric substrate; a bias electrode disposed inside the dielectric substrate; and a discharge suppression component embedded in the dielectric substrate in a manner surrounding the pores and having conductivity, wherein the discharge suppression component is electrically independent.

[0009] [2] According to the electrostatic chuck component of [1], wherein the discharge suppression component includes a plurality of pins, the pins being arranged circumferentially spaced around the central axis of the air hole and each being continuous along the thickness direction.

[0010] [3] According to the electrostatic chuck component of [1], wherein the discharge suppression component is formed as a cylindrical shape that extends circumferentially around the central axis of the air hole and is continuous in the thickness direction.

[0011] [4] The electrostatic chuck component according to any one of [1] to [3], wherein the discharge suppression component is disposed radially outside the air hole, separate from the inner peripheral surface of the air hole.

[0012] [5] The electrostatic chuck component according to any one of [1] to [4] further comprises a conductive shielding layer disposed inside the dielectric substrate on the opposite side to the mounting surface relative to the adsorption electrode and the bias electrode, extending radially outward from the outer periphery of the discharge suppression component centered on the discharge suppression component.

[0013] [6] An electrostatic chuck device comprising: an electrostatic chuck component as described in any one of [1] to [5]; and a base supporting the electrostatic chuck component from the opposite side of the mounting surface, wherein the discharge suppression component does not contact the base.

[0014] Invention Effects According to one aspect of the present invention, an electrostatic chuck device capable of suppressing abnormal discharge inside pores can be provided. Attached Figure Description

[0015] Figure 1 This is a schematic cross-sectional view showing an example of the electrostatic chuck device according to the first embodiment.

[0016] Figure 2 This is a cross-sectional schematic diagram showing an example of a discharge suppression component provided in the electrostatic chuck device of the first embodiment.

[0017] Figure 3 This is a cross-sectional schematic diagram showing an example of a discharge suppression component provided in the electrostatic chuck device of the second embodiment.

[0018] Figure 4 This is a diagram showing an example of the equipotential line near the air hole of an electrostatic chuck device that does not have a discharge suppression component, a comparative example.

[0019] Figure 5 This is a diagram showing an example of the equipotential line near the air hole (the part where the pin exists) of the electrostatic chuck device in the first embodiment.

[0020] Figure 6 This is a diagram showing an example of the equipotential lines of other parts (between pins) near the air holes of the electrostatic chuck device in the first embodiment.

[0021] Figure 7This is a diagram showing an example of the equipotential line of the electrostatic chuck device according to an embodiment of the second embodiment.

[0022] Figure 8 This is a schematic cross-sectional view of an electrostatic chuck device according to a variation of the embodiment. Detailed Implementation

[0023] Hereinafter, preferred embodiments of the electrostatic chuck device of the present invention will be described with reference to the accompanying drawings. Furthermore, in all the following drawings, the dimensions or proportions of the constituent components may be appropriately altered for ease of understanding.

[0024] Furthermore, the following description is provided for the purpose of better understanding the spirit of the invention and is not intended to limit the invention unless otherwise specified. For example, unless otherwise specified, conditions such as materials, quantities, types, quantities, sizes, shapes, positions, combinations, and ratios can be changed, added, or omitted as needed.

[0025] [First Implementation] (The entire electrostatic chuck device) Figure 1 This is a schematic cross-sectional view showing a preferred example of the electrostatic chuck device of this embodiment.

[0026] Figure 1 The electrostatic chuck device 1A shown is disposed in the vacuum container of the plasma processing apparatus with the mounting surface 11a on which the wafer (plate sample) W is mounted facing upward.

[0027] In addition, the Z-axis is shown in each figure to illustrate the reference of the electrostatic chuck device. The Z-axis direction is, for example, the vertical direction. The central axis O of the mounting surface 11a is parallel to the Z-axis. Furthermore, the arrangement of the electrostatic chuck device 1A relative to the vertical direction is one example, but other arrangements are also possible.

[0028] The electrostatic chuck device 1A includes: an electrostatic chuck plate (electrostatic chuck component) 10A, which adsorbs and supports plate-shaped samples such as wafers W; and a base 20, which supports the electrostatic chuck plate 10A.

[0029] (Base) The base 20 is composed of a disc-shaped component with thickness. The base 20 supports the electrostatic chuck plate 10A from below (opposite to the mounting surface 11a). The material constituting the base 20 can be selected as needed, preferably a metal with excellent thermal conductivity, electrical conductivity, and machinability, or a composite material containing these metals, or a conductive ceramic, or a composite material of said metal and ceramic (MMC: Metal Matrix Composition). For example, aluminum, aluminum alloys, copper, copper alloys, stainless steel, etc., are preferably used as the metal. The conductive ceramic is preferably composed of a material with high thermal conductivity and a conductive material.

[0030] The volume ratio of the highly thermally conductive material and the conductive material constituting the conductive ceramic can be arbitrarily selected, but is preferably 10:90 to 90:10.

[0031] As a material with high thermal conductivity, it is preferably selected from at least one of the following groups: AlN, SiC, GaN, SiO2, Al2O3, SmAlO3, MgO, SiO2, Si3N4, Al(OH)3, MgO, Mg(OH)2, BN, ZnO, BeO, B4C, carbon, aluminum, copper, silver, and gold. As a material with high thermal conductivity, it is preferably selected from at least one of the following groups: SiC, TiO2, TiN, TiC, W, WC, Mo, MoC, Mo2C, TaC, TaN, NbC, VC, and C. The conductive ceramic can be composed of, for example, AlN and TiN, AlN and Mo, or AlN, TiN, and Mo.

[0032] In this embodiment, the base 20 can be a water-cooled base with an internal flow path (not shown) for circulating refrigerant such as water.

[0033] The upper surface 20t of the base 20 is bonded to the lower surface 11b of the dielectric substrate 11 via the adhesive layer 25. The adhesive layer 25 can be arbitrarily selected. For example, it can be a heat-resistant resin such as polyimide resin, silicone resin, or epoxy resin, or an insulating sheet or film adhesive resin. It can also be a silicone resin containing aluminum nitride particles or a surface coated with aluminum nitride particles, or a metal solder.

[0034] (Electrostatic chuck plate) The electrostatic chuck plate 10A has a dielectric substrate 11, an adsorption electrode 30, a bias electrode 40, and a discharge suppression component 50A. The adsorption electrode 30, the bias electrode 40, and the discharge suppression component 50A are respectively embedded in the dielectric substrate 11.

[0035] (Dielectric substrate) The dielectric substrate 11 is a plate-shaped component that appears circular or approximately circular when viewed from above. In this specification, the thickness direction of the dielectric substrate 11 is sometimes simply referred to as the "thickness direction." Furthermore, in this specification, the side of the thickness direction for mounting the wafer W is designated as the "upper side," and the opposite side as the "lower side," in describing the electrostatic chuck device. The terms "upper side" and "lower side" in this specification represent one example of the orientation of the electrostatic chuck device during use, and are not limited to any particular orientation.

[0036] The dielectric substrate 11 is preferably made of a composite sintered body that has mechanical strength and durability against corrosive gases and their plasmas. As the dielectric material constituting the dielectric substrate 11, ceramics that have mechanical strength and durability against corrosive gases and their plasmas are preferably used. For example, alumina sintered bodies, aluminum nitride sintered bodies, and alumina-silicon carbide composite sintered bodies are preferably used as the ceramic constituting the dielectric substrate 11.

[0037] A mounting surface 11a for mounting a wafer W is formed on the upper surface of the dielectric substrate 11. That is, a mounting surface 11a for mounting a wafer W is provided on the dielectric substrate 11. In this embodiment, a plurality of protrusions 12 are formed on the upper surface of the dielectric substrate 11 at predetermined intervals. The front end faces of the plurality of protrusions 12 form the mounting surface 11a. In the dielectric substrate 11, recesses 13 are formed between adjacent plurality of protrusions 12, recessed downward relative to the mounting surface 11a. The bottom surface 13b of the recesses 13 faces upward (towards the wafer W side).

[0038] A vent 8 is provided in the dielectric substrate 11. The vent 8 penetrates the dielectric substrate 11 along the thickness direction. When viewed from the thickness direction, the vent 8 is circular. The vent 8 is connected to a gas supply device (not shown). The vent 8 supplies cooling gas such as helium (He) to the space between the wafer W placed on the mounting surface 11a and the bottom surface 13b of the recess 13. The supplied cooling gas cools the wafer W placed on the mounting surface 11a. In this embodiment, the case where only one vent 8 is formed in the central part of the electrostatic chuck device 1A will be described, but multiple vents 8 may also be provided in the electrostatic chuck device 1A.

[0039] (Adsorption electrode and bias electrode) The adsorption electrode 30 and the bias electrode 40 are layered electrodes and conductive components embedded in the dielectric substrate 11. The adsorption electrode 30 and the bias electrode 40 are conductive; that is, they are made of a material with a resistivity of 0.5 Ωm or less. The adsorption electrode 30 and the bias electrode 40 are arranged sequentially from top to bottom within the dielectric substrate 11. In other words, the adsorption electrode 30 is preferably disposed between the bias electrode 40 and the mounting surface 11a.

[0040] The adsorption electrode 30 is located inside the dielectric substrate 11. The adsorption electrode 30 extends in layers along a plane orthogonal to the thickness direction of the dielectric substrate 11. Preferably, a first hole 30a is provided in the adsorption electrode 30 for the discharge suppression member 50A to pass through. When viewed in the thickness direction, the first hole 30a is a region formed in a manner surrounding the discharge suppression member 50A without a hole shape in which the adsorption electrode 30 is formed. The inner diameter of the first hole 30a is sufficiently large relative to the outer diameter of the discharge suppression member 50A. The inner edge of the first hole 30a is disposed at a distance from the outer peripheral surface of the discharge suppression member 50A.

[0041] The adsorption electrode 30 is disposed at a predetermined dimension lower than the mounting surface 11a and the bottom surface 13b. The adsorption electrode 30 is connected to the DC power supply 101 via a first power supply section 31 extending downward. The adsorption electrode 30 generates an electrostatic adsorption force by the DC current supplied by the DC power supply 101, and adsorbs the wafer W onto the mounting surface 11a. In addition, the adsorption electrode 30 is not limited to a unipolar adsorption electrode, but can also be a bipolar adsorption electrode composed of two electrodes that are semi-circular when viewed from above. Furthermore, when viewed from the thickness direction, the adsorption electrode 30 can be disposed only in a portion of the circumferential region centered on the discharge suppression member 50A described later. The number or shape of the adsorption electrode 30 can be arbitrarily selected. Furthermore, when viewed from the thickness direction, multiple adsorption electrodes 30 can also be disposed at intervals along the circumferential direction centered on the discharge suppression member 50A.

[0042] The bias electrode 40 is disposed at a distance from the adsorption electrode 30 on the lower side of the adsorption electrode 30 (opposite to the mounting surface 11a side). The bias electrode 40 extends in layers along a plane orthogonal to the thickness direction of the dielectric substrate 11. The bias electrode 40 is connected to the AC power supply 102 via a second power supply section 41 extending downward.

[0043] Preferably, the bias electrode 40 has a second hole 40a through which the discharge suppression member 50A passes and a third hole 40h through which the first power supply member 31 passes. Viewed in the thickness direction, the second hole 40a is a region formed in a manner surrounding the discharge suppression member 50A, without a hole shape to which the bias electrode 30 is formed. The inner diameter of the second hole 40a is sufficiently large relative to the outer diameter of the discharge suppression member 50A. The inner edge of the second hole 40a is disposed at a distance from the outer peripheral surface of the discharge suppression member 50A. In this embodiment, the inner diameter of the second hole 40a is approximately equal to the inner diameter of the first hole 30a. Similarly, viewed in the thickness direction, the third hole 40h is a region formed in a manner surrounding the first power supply member 31, without a hole shape to which the bias electrode 30 is formed. The inner diameter of the third hole 40h is sufficiently large relative to the outer diameter of the first power supply member 31. The inner edge of the third hole 40h is arranged at a distance from the outer peripheral surface of the first power supply section 31.

[0044] In this embodiment, when viewed from the thickness direction, the outer periphery 40b of the bias electrode 40 and the outer periphery 30b of the adsorption electrode 30 are positioned approximately at the same location. Therefore, in this embodiment, the bias electrode 40 is configured to cover approximately the entire adsorption electrode 30 from below. Furthermore, when viewed from the thickness direction, the bias electrode 40 only needs to overlap with at least a portion of the adsorption electrode 30. That is, when viewed from the thickness direction, at least a portion of the bias electrode 40 overlaps with the adsorption electrode 30. Moreover, when viewed from the thickness direction, the entire bias electrode 40 of this embodiment overlaps with the adsorption electrode 30.

[0045] (Discharge suppression component) Figure 2 This is a cross-sectional schematic diagram showing the discharge suppression component 50A installed in the electrostatic chuck device 1A of this embodiment. This figure is a schematic diagram showing a radial cut around the discharge suppression component 50A surrounding the air hole 8.

[0046] like Figure 1 , Figure 2 As shown, the discharge suppression component 50A is embedded in the dielectric substrate 11 in a manner surrounding the vent 8. The discharge suppression component 50A suppresses discharge within the vent 8. In this embodiment, the discharge suppression component 50A includes multiple pins 51 surrounding the vent 8. The multiple pins 51 are arranged at intervals around each other on the same circle in the circumferential direction centered on the vent 8. Each pin 51 extends along the thickness direction of the dielectric substrate 11. When viewed from the thickness direction, the pin 51 is, for example, circular. The number, shape, and size of the pins 51 can be arbitrarily selected. When viewed from the thickness direction, the shape of the pin 51 is not limited to circular; for example, it can also be a polygonal shape such as a quadrilateral, pentagon, hexagon, or octagon. The pin 51 can be, for example, a cylinder or a polygonal prism. Furthermore, the number of pins 51 is, for example, only three or more. In this embodiment, six pins 51 are arranged at equal intervals in the circumferential direction. The number of pins can be, for example, 3 to 5, 6 to 8, 9 to 15, or 16 to 25. The distance from the vent 8 to the pin 51 can be arbitrarily selected; for example, it can be less than or greater than the diameter of the vent 8. In this embodiment, the shape of the pin 51 and the distance from the vent 8 to each pin 51 are the same.

[0047] These multiple pins 51 are disposed separately from the radially outer surface of the vent 8 relative to the inner peripheral surface of the vent 8. In other words, the dielectric material forming the dielectric substrate 11 is located between the multiple pins 51 constituting the discharge suppression component 50A and the inner peripheral surface of the vent 8.

[0048] And, as Figure 1As shown, one end 51s of each pin 51 is positioned at a predetermined distance below the mounting surface 11a and the bottom surface 13b. The other end 51t of each pin 51 is positioned at a predetermined distance above the lower surface 11b of the dielectric substrate 11. That is, each pin 51 does not contact the metal base 20. The ends of the pins 51 are located inside the dielectric substrate 11 and are not exposed to the outside.

[0049] The discharge suppression component 50A, which has multiple pins 51, is provided in an electrically independent manner. That is, the multiple pins 51 embedded in the dielectric substrate 11 are not electrically connected to other conductors, such as the adsorption electrode 30 or the bias electrode 40. For example, the discharge suppression component 50A may only be in direct contact with the dielectric material forming the dielectric substrate 11.

[0050] The adsorption electrode 30, the bias electrode 40, and the discharge suppression component 50A are formed of a conductive material. The conductive material used in the discharge suppression component 50A can be arbitrarily selected, but is preferably at least one selected from the group consisting of molybdenum carbide (Mo2C), molybdenum (Mo), tungsten carbide (WC), tungsten (W), tantalum carbide (TaC), tantalum (Ta), silicon carbide (SiC), carbon black, carbon nanotubes, and carbon nanofibers. Furthermore, to control resistivity, the conductive material used in the adsorption electrode 30, the bias electrode 40, and the discharge suppression component 50A can also be composed of at least one of alumina (Al2O3), aluminum nitride (AlN), silicon nitride (Si3N4), yttrium (III) oxide (Y2O3), yttrium aluminum garnet (YAG), and SmAlO3.

[0051] The adsorption electrode 30, bias electrode 40, and discharge suppression component 50A can be components pre-formed into a specified shape, or they can be formed by 3D printing or the like. The adsorption electrode 30, bias electrode 40, and discharge suppression component 50A can also be formed by stacking them multiple times to form the dielectric substrate 11, and arranged in such a way that they are sequentially embedded in the dielectric substrate 11.

[0052] In the electrostatic chuck plate 10A of this embodiment, an adsorption electrode 30 and a bias electrode 40 are disposed inside the dielectric substrate 11. Therefore, due to the voltage applied to these electrodes 30 and 40, a potential difference is generated in various parts within the dielectric substrate 11. The electrostatic chuck plate 10A of this embodiment includes a conductive discharge suppression member 50A disposed in a manner that surrounds the pores 8 of the dielectric substrate 11. According to this structure, the pores 8 are surrounded by the conductive discharge suppression member 50A, thus suppressing the influence caused by the electric fields of the adsorption electrode 30 and the bias electrode 40 from reaching the pores 8. As a result, a large potential difference is less likely to be generated within the pores 8, and the discharge of cooling gas within the pores 8 can be suppressed.

[0053] In this embodiment, the discharge suppression component 50A is embedded in the dielectric substrate 11 in a manner that surrounds the pore 8, and suppresses discharge within the pore 8. According to this structure, the discharge suppression component 50A can suppress the electric field caused by the adsorption electrode 30 and the bias electrode 40 from reaching the radially inner side of the discharge suppression component 50A. As a result, the increase in potential difference within the pore 8 radially inner side of the discharge suppression component 50A can be effectively suppressed. Therefore, abnormal discharge inside the pore 8 can be suppressed.

[0054] In the electrostatic chuck plate 10A of this embodiment, the discharge suppression component 50A includes a plurality of pins 51, which are arranged at intervals along the circumferential direction around the central axis of the vent 8. With this structure, abnormal discharge inside the vent 8 can be suppressed with a simple design.

[0055] In the electrostatic chuck plate 10A of this embodiment, the discharge suppression member 50A is disposed separately from the radially outer side of the vent 8 relative to the inner peripheral surface of the vent 8. According to this structure, the dielectric material forming the dielectric substrate 11 is located between the inner peripheral surface of the vent 8 and the discharge suppression member 50A, which can more effectively suppress the electric field caused by the adsorption electrode 30 and the bias electrode 40 from reaching the radially inner side of the discharge suppression member 50A.

[0056] [Second Implementation] Figure 3 This is a cross-sectional schematic diagram showing the discharge suppression component provided in the electrostatic chuck device of the second embodiment. In the electrostatic chuck device 1B of this embodiment, the structure of the discharge suppression component 50B is different from that of the electrostatic chuck device 1A described above, while other structures are common to the electrostatic chuck device 1A. Therefore, the discharge suppression component 50B will be mainly described, and the description of the structures common to the electrostatic chuck device 1A will be omitted.

[0057] like Figure 1 As shown, the electrostatic chuck device 1B includes an electrostatic chuck plate 10B and a base 20. The electrostatic chuck plate 10B has a dielectric substrate 11, an adsorption electrode 30, a bias electrode 40, and a discharge suppression component 50B.

[0058] The discharge suppression component 50B is embedded in the dielectric substrate 11 in a manner that surrounds the vent 8. The discharge suppression component 50B suppresses discharge within the vent 8. Viewed in the thickness direction, the discharge suppression component 50B of this embodiment is formed as a cylindrical component that extends continuously in the circumferential direction centered on the vent 8 and is continuous in the thickness direction. Viewed in the thickness direction, the cross-sectional shape of the discharge suppression component 50B of this embodiment is circular (annular), and the whole is cylindrical. Viewed in the thickness direction, the cross-sectional shape of the discharge suppression component 50B is not limited to a circle, and may also be a polygonal shape such as a quadrilateral, hexagon, or octagon.

[0059] The discharge suppression component 50B is separated from the inner peripheral surface of the vent 8 and is disposed radially outside the vent 8. In other words, the dielectric material forming the dielectric substrate 11 is located between the discharge suppression component 50B and the inner peripheral surface of the vent 8.

[0060] Furthermore, one end 50s of the discharge suppression component 50B is positioned at a predetermined distance below the mounting surface 11a and the bottom surface 13b. The other end 50t of the discharge suppression component 50B is positioned at a predetermined distance above the lower surface 11b of the dielectric substrate 11. That is, the discharge suppression component 50B does not contact the metal base 20.

[0061] The discharge suppression component 50B is provided in an electrically independent manner. That is, the discharge suppression component 50B embedded in the dielectric substrate 11 is not electrically connected to other conductors such as the adsorption electrode 30 or the bias electrode 40. In this embodiment, the discharge suppression component 50B is located inside the dielectric substrate 11 and is not exposed to the outside.

[0062] In this embodiment, the discharge suppression component 50B is embedded in the dielectric substrate 11 in a manner that surrounds the pore 8, thereby suppressing discharge within the pore 8. According to this structure, the discharge suppression component 50B can suppress the electric field caused by the adsorption electrode 30 and the bias electrode 40 from reaching the radially inner side of the discharge suppression component 50B. As a result, the increase in potential difference within the pore 8 radially inner side of the discharge suppression component 50B can be effectively suppressed. Therefore, abnormal discharge inside the pore 8 can be suppressed.

[0063] In the electrostatic chuck plate 10B of this embodiment, the discharge suppression member 50B is formed as a cylindrical shape that extends circumferentially around the central axis of the vent 8 and is continuous in the thickness direction. According to this structure, the electric field caused by the adsorption electrode 30 and the bias electrode 40 can be suppressed from reaching the radially inner side of the discharge suppression member 50B throughout the entire circumferential region of the discharge suppression member 50B. As a result, the discharge of cooling gas within the vent 8 can be effectively suppressed.

[0064] Generally, it is known that a wafer W mounted on a mounting surface 11a emits secondary electrons from its lower surface side when etch gas collides with its upper surface. Furthermore, with the increasing power of etching in recent years, the frequency of this secondary electron emission phenomenon is increasing. If secondary electrons emitted from the lower surface side of the wafer W penetrate into the interior of the vent hole 8, the cooling gas within the vent hole 8 may ionize, causing a discharge within the vent hole 8. The inventors have focused on the fact that discharges resulting from the ionization of the cooling gas are more likely to occur when the potential difference in the thickness direction within the vent hole 8 between the lower surface of the wafer W and the upper surface of the substrate 20 is large. The inventors have attempted to reduce the potential difference within the vent hole 8, thereby conceiving the structures involved in various embodiments and their modifications.

[0065] (Example: Simulation) Simulations were conducted to demonstrate the superiority of the electrostatic chuck device with discharge suppression components. Figures 4-7 In the simulation, simulation results were obtained demonstrating the superiority of the electrostatic chuck device 1A of the first embodiment and the electrostatic chuck device 1B of the second embodiment. Furthermore, the configuration of the devices was simplified in the simulation to facilitate comparison.

[0066] Figure 4 The simulation results are shown for the electrostatic chuck device 1P, which is a comparative example without the discharge suppression component 50A. Figure 5 , Figure 6 The simulation results show the electrostatic chuck device 1A of the first embodiment. Figure 5 , Figure 6 The electrostatic chuck device 1A shown is with Figure 4 Compared to the electrostatic chuck device 1P shown in the comparative example, it has a discharge suppression component 50A. Figure 7 The simulation results show the electrostatic chuck device 1B of the second embodiment. This electrostatic chuck device 1B is related to... Figure 4 Compared to the electrostatic chuck device 1P shown in the comparative example, it has a discharge suppression component 50B.

[0067] exist Figures 4-7 The diagram schematically illustrates the simulation results of the equipotential lines of the electric field generated by the adsorption electrode 30 and the bias electrode 40.

[0068] exist Figure 4 In the electrostatic chuck device 1P of the comparative example shown, on the lower side of the wafer W, the equipotential lines are concentrated and arranged vertically around the portion where the vent 8 is provided, thereby confirming that the potential difference on the lower side of the wafer W is larger.

[0069] On the other hand, Figure 5 , Figure 6 In the simulation results of the electrostatic chuck device 1A shown, most of the equipotential lines emitted from the end of the bias electrode 40 are in the portion where the pin 51 is located (see reference). Figure 5 ), the portion between adjacent pins 51 in the circumferential direction (reference) Figure 6 In any part of the ), it extends radially outward from the region where the discharge suppression component 50A is provided to the upper end of the electrostatic chuck plate 10A. Figure 7In the simulation results of the electrostatic chuck device 1B of the illustrated embodiment, most of the equipotential lines emanating from the end of the bias electrode 40 extend to the upper end of the electrostatic chuck plate 10B at a position radially outward from the region where the discharge suppression member 50B is provided. The number of equipotential lines disposed on the lower side of the wafer W in the simulation results of the electrostatic chuck devices 1A and 1B of the embodiments is less than the number of equipotential lines disposed on the lower side of the wafer W in the simulation results of the electrostatic chuck device 1P of the comparative example. Therefore, in the electrostatic chuck devices 1A and 1B of the embodiments, it can be confirmed that the potential difference on the lower side of the wafer W is smaller.

[0070] (Modifications of the implementation method) Figure 8 This is a cross-sectional view of a modified electrostatic chuck device according to the second embodiment. The electrostatic chuck device 1C of this modified embodiment differs from the electrostatic chuck device 1B of the second embodiment only in the structure of the discharge suppression component. Furthermore, components that are identical in arrangement to those in the second embodiment are labeled with the same reference numerals, and their descriptions are omitted.

[0071] like Figure 8 As shown, the electrostatic chuck device 1C in this modified example includes an electrostatic chuck plate 10C and a base 20, similar to the embodiments described above. Furthermore, the electrostatic chuck plate 10C includes a dielectric substrate 11, an adsorption electrode 30, a bias electrode 40, and a discharge suppression component 50C.

[0072] The discharge suppression component 50C of this modification includes a shielding layer 55. The shielding layer 55 is disposed inside the dielectric substrate 11, spaced apart from the adsorption electrode 30 and the bias electrode 40, on the lower side of these electrodes (opposite to the mounting surface 11a side). The shielding layer 55 extends in a layered manner along a plane orthogonal to the thickness direction of the dielectric substrate 11.

[0073] The shielding layer 55 contacts and is electrically connected to the outer peripheral surface of the cylindrical discharge suppression member 50C. The shielding layer 55 extends radially outward from the outer peripheral surface of the discharge suppression member 50C. In this embodiment, the shielding layer 55 is formed as a flange extending in a ring shape along the circumferential direction. The radial width of the shielding layer 55 can be constant. Alternatively, the shielding layer 55 may be provided only in a portion of the circumferential direction. For example, multiple shielding layers 55 may be provided at intervals along the circumferential direction. In this case, the multiple shielding layers 55 extend radially from the outer peripheral surface of the discharge suppression member 50C. The multiple shielding layers 55 can be of any chosen number or shape; for example, when viewed from the thickness direction, they can be quadrilateral, approximately quadrilateral, fan-shaped, or other shapes. In this embodiment, when viewed from the thickness direction, the outer edge 55s located radially outward of the shielding layer 55 completely overlaps with the bias electrode 40. The discharge suppression member 50C and the shielding layer 55 can be formed of the same material. The discharge suppression component 50C and the shielding layer 55 may also be in direct contact only with the dielectric material forming the dielectric substrate 11.

[0074] The electrostatic chuck plate 10C of this modification includes a shielding layer 55 disposed inside the dielectric substrate 11 on the side opposite (below) to the mounting surface 11a, opposite to the adsorption electrode 30 and the bias electrode 40, and extending radially outward from the outer periphery of the discharge suppression member 50C centered on the discharge suppression member 50C, and is conductive. As a result, an electric field is formed that avoids the shielding layer 55, and the potential difference on the lower side of the discharge suppression member 50C is less likely to increase. Consequently, a large potential difference can be suppressed within the vent 8 on the lower side of the discharge suppression member 50C, and the discharge of cooling gas in the vent 8 can be suppressed.

[0075] The embodiments and variations of the present invention have been described above. However, each structure and combination thereof in the embodiments and variations are examples, and structural additions, omissions, substitutions, and other changes can be made without departing from the spirit of the present invention. Furthermore, the present invention is not limited to the embodiments.

[0076] Explanation of reference numerals in the attached figures 1A~1C - Electrostatic Chuck Device 1P-Electrostatic Chuck Device (Comparative Example) 8-pores 10A~10C - Electrostatic chuck plate (electrostatic chuck component) 11-Dielectric substrate 11a-Placement Surface 11b-lower surface 12-Protrusion 13-Concave 13b-bottom 20-base 20t-upper surface 25-Adhesive layer 30-Adsorption Electrode 30a-First Hole Section 30b - outer periphery 31-First Power Supply Department 40-Bias Electrode 40a - Second Hole 40b - outer periphery 40h - Third Hole 41-Second Power Supply Department 50A~50C - Discharge Suppression Component 50s - one end 50t - the other end 51-sales 51s - one end 51t - the other end 55-Shielding layer 101-DC Power Supply 102-AC Power Supply O-Central Axis W-wax (plate-shaped sample) ZZ axis

Claims

1. An electrostatic chuck component, comprising: The dielectric substrate has a mounting surface for placing a plate-shaped sample and pores penetrating along the thickness direction, and is plate-shaped. An adsorption electrode is disposed inside the dielectric substrate; A bias electrode is disposed inside the dielectric substrate; and A discharge suppression component is embedded in the dielectric substrate in a manner that surrounds the pores, and is conductive. The discharge suppression component is electrically independent.

2. The electrostatic chuck component according to claim 1, wherein, The discharge suppression component includes a plurality of pins, which are arranged circumferentially spaced around the central axis of the vent and are continuous along the thickness direction.

3. The electrostatic chuck component according to claim 1, wherein, The discharge suppression component is formed as a cylindrical shape that extends circumferentially around the central axis of the vent and is continuous along the thickness direction.

4. The electrostatic chuck component according to claim 1, wherein, The discharge suppression component is separated from the inner circumferential surface of the vent and is disposed radially outside the vent.

5. The electrostatic chuck component according to claim 1, further comprising a conductive shielding layer disposed inside the dielectric substrate on the opposite side to the mounting surface relative to the adsorption electrode and the bias electrode, extending radially outward from the outer periphery of the discharge suppression component centered on the discharge suppression component.

6. An electrostatic chuck device, comprising: The electrostatic chuck component according to any one of claims 1 to 5; and The base supports the electrostatic chuck component from the opposite side of the mounting surface. The discharge suppression component is not in contact with the base.

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