Electrostatic chuck component and electrostatic chuck device

Abstract

An electrostatic chuck component includes: a plate-shaped dielectric substrate provided with a placement surface on which a plate-shaped sample is placed and an air hole penetrating in a thickness direction; an adsorption electrode disposed inside the dielectric substrate; a bias electrode disposed inside the dielectric substrate; a cylindrical member surrounding the air hole and having conductivity; and a conductive shield layer that is disposed inside the dielectric substrate on the opposite side of the adsorption electrode and the bias electrode from the mounting surface side, and that extends from the outer peripheral surface of the cylindrical member toward the outside in the radial direction centered on the cylindrical member.

Description

Technical Field

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

[0002] This application claims priority based on Japanese Patent Application No. 2023-100070 filed in Japan on June 19, 2023, the contents of which are incorporated herein by reference. Background Art

[0003] Electrostatic chuck devices for supporting substrates such as semiconductor wafers are known. For example, Patent Document 1 describes an electrostatic chuck device having a structure having multiple air holes within a sample stage for electrostatically adsorbing an object to be processed. These air holes are used to supply a heat-conducting gas between the object to be processed and the sample stage to control the temperature of the object to be processed.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2010-182763 Summary of the Invention

[0007] Technical issues to be solved by the invention

[0008] In electrostatic chucks like the one described above, the through-holes for gas supply can sometimes serve as the starting point for discharges that can damage semiconductor wafers. In recent years, plasma etching equipment used in semiconductor manufacturing has been moving toward higher power levels to enable deep hole machining, driven by the increasing multi-layer nature of semiconductors. Therefore, it is crucial to suppress abnormal discharges within the gas holes.

[0009] One object of the present invention is to provide an electrostatic chuck device capable of suppressing abnormal discharge inside a gas hole.

[0010] Means for solving technical problems

[0011] The present invention provides an electrostatic chuck component and an electrostatic chuck device as described below.

[0012] It is also preferable to combine two or more of the features described below as needed.

[0013] [1] An electrostatic chuck component comprising: a plate-like dielectric substrate having a mounting surface for mounting a plate-like sample and air holes extending through the substrate in a thickness direction; an adsorption electrode disposed within the dielectric substrate; a bias electrode disposed within the dielectric substrate; a cylindrical component surrounding the air holes and having conductivity; and a shielding layer disposed within the dielectric substrate on a side opposite to the mounting surface relative to the adsorption electrode and the bias electrode, extending from the outer peripheral surface of the cylindrical component to the radially outer side centered on the cylindrical component and having conductivity.

[0014] [2] The electrostatic chuck component according to [1], wherein at least a portion of the shield layer overlaps with the bias electrode when viewed in the thickness direction.

[0015] [3] The electrostatic chuck component according to [1] or [2], wherein the shield layer is formed into a flange shape extending annularly along a circumferential direction centered on the cylindrical member.

[0016] [4] The electrostatic chuck component according to [3], wherein the outer edge of the shield layer entirely overlaps with the bias electrode when viewed in the thickness direction.

[0017] [5] An electrostatic chuck component according to any one of [1] to [4], wherein one end of the tubular component extends to the mounting surface side of the dielectric substrate, and the other end of the tubular component extends to the lower surface of the dielectric substrate facing the side opposite to the mounting surface side.

[0018] [6] The electrostatic chuck component according to any one of [1] to [5], wherein the cylindrical member is grounded.

[0019] [7] An electrostatic chuck device comprising: the electrostatic chuck component according to any one of [1] to [6]; and a base supporting the electrostatic chuck component from a side opposite to the mounting surface, the tubular component being in contact with the base.

[0020] [8] An electrostatic chuck device according to [7], wherein the air hole penetrates the base along the thickness direction, one end of the tubular member extends to the mounting surface side of the dielectric substrate, and the other end of the tubular member extends to the lower surface of the base facing the side opposite to the mounting surface side.

[0021] Effects of the Invention

[0022] According to the above aspect of the present invention, it is possible to provide an electrostatic chuck device capable of suppressing abnormal discharge inside a gas hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1This is a schematic cross-sectional view showing an example of the electrostatic chuck device according to the first embodiment.

[0024] Figure 2 This is a diagram showing equipotential lines of an electrostatic chuck device according to a comparative example.

[0025] Figure 3 This is a diagram showing equipotential lines in the electrostatic chuck device of the embodiment.

[0026] Figure 4 This is a schematic cross-sectional view showing an example of an electrostatic chuck device according to a second embodiment.

[0027] Figure 5 It is a schematic cross-sectional view of an electrostatic chuck device according to a first modified example of the embodiment.

[0028] Figure 6 It is a schematic cross-sectional view of an electrostatic chuck device according to a second modified example of the embodiment. DETAILED DESCRIPTION

[0029] Hereinafter, preferred examples of various embodiments of the electrostatic chuck device of the present invention will be described with reference to the accompanying drawings. In all the following drawings, the dimensions and ratios of the components may be appropriately varied to facilitate easier viewing.

[0030] Furthermore, this embodiment is only described in detail to facilitate a better understanding of the purpose of the invention and does not limit the present invention unless otherwise specified. For example, unless otherwise specifically limited, materials, amounts, types, quantities, sizes, shapes, positions, ratios, temperatures, and other conditions may be changed, added, or omitted as needed. Preferred examples may be replaced or shared between the embodiments described below. Unless otherwise specified, the first and second embodiments or variations described below may share preferred features or conditions.

[0031] [First embodiment]

[0032] (Overall electrostatic chuck device)

[0033] Figure 1 It is a schematic cross-sectional view showing an example of the electrostatic chuck device according to the present embodiment.

[0034] Figure 1 The electrostatic chuck device 1A shown is appropriately placed in a vacuum chamber of a plasma processing apparatus, for example, with a placement surface 11 a on which a wafer (plate-shaped sample) W is placed facing upward.

[0035] In each figure, the Z-axis is shown 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. The arrangement of the electrostatic chuck device 1A relative to the vertical direction is merely an example; other arrangements are also possible.

[0036] The electrostatic chuck device 1A includes an electrostatic chuck plate (electrostatic chuck member) 10A for suction-supporting a plate-shaped sample such as a wafer W, and a base 20 for supporting the electrostatic chuck plate 10A.

[0037] (abutment)

[0038] The base 20 is formed by a disc-shaped component (such as a metal component) with a thickness. The base 20 supports the electrostatic chuck plate 10A from the bottom (the side opposite to the mounting surface 11a). As the material constituting the base 20, it can be arbitrarily selected, for example, as long as it is a metal with excellent thermal conductivity, electrical conductivity, and processability or a composite material containing these metals, it can be appropriately used without particular restrictions. For example, aluminum, aluminum alloy, copper, copper alloy, stainless steel, etc. can be appropriately used. The base 20 of this embodiment can have a structure that can be arbitrarily selected, or it can be a water-cooled base having a flow path (not shown) inside that circulates a liquid refrigerant such as water. The refrigerant can be a gas such as He gas or N2 gas.

[0039] 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 material forming the adhesive layer 25 can be arbitrarily selected, including, for example, heat-resistant resins such as polyimide resin, silicone resin, and epoxy resin, or insulating sheet-shaped or film-shaped adhesive resins.

[0040] (Electrostatic chuck plate)

[0041] The electrostatic chuck plate 10A includes a dielectric substrate 11 , a cylindrical member 51 , an adsorption electrode 30 , a bias electrode 40 , and a shield layer 55A. The cylindrical member 51 , the adsorption electrode 30 , the bias electrode 40 , and the shield layer 55A are embedded in the dielectric substrate 11 .

[0042] (Dielectric substrate)

[0043] The dielectric substrate 11 is a plate-shaped member that is circular or substantially circular in plan view. In this specification, the thickness direction of the dielectric substrate 11 is sometimes referred to simply as the "thickness direction." Furthermore, in this specification, the electrostatic chuck device is described with the side on which the wafer W is placed in the thickness direction being referred to as the "upper side," and the opposite side being referred to as the "lower side." The terms "upper side" and "lower side" in this specification represent examples of postures used when the electrostatic chuck device is in use and do not limit the postures used when the electrostatic chuck device is in use.

[0044] The dielectric substrate 11 is preferably formed of a composite sintered body having mechanical strength and durability against corrosive gases and their plasma. As the dielectric material constituting the dielectric substrate 11, ceramics having mechanical strength and durability against corrosive gases and their plasma can be suitably used. Examples of ceramics constituting the dielectric substrate 11 include preferably an alumina sintered body, an aluminum nitride sintered body, and an aluminum oxide-silicon carbide composite sintered body.

[0045] The upper surface of the dielectric substrate 11 includes a placement surface 11a on which the wafer W is placed. Specifically, the dielectric substrate 11 is provided with the placement surface 11a on which the wafer W is placed. In this embodiment, a plurality of protrusions 12 are formed on the upper surface of the dielectric substrate 11 at predetermined intervals. The distal ends of the protrusions 12 form the placement surface 11a. Between adjacent protrusions 12, recesses (valleys) 13 are formed in the dielectric substrate 11. These recesses 13 are recessed downward relative to the placement surface 11a. The bottom surfaces 13b of the recesses 13 face upward (toward the wafer W).

[0046] An air hole 8 is provided in the dielectric substrate 11. The air hole 8 penetrates the dielectric substrate 11 in the thickness direction. When viewed from the thickness direction, the air hole 8 is circular. The air hole 8 is connected to a gas supply device (not shown). The air hole 8 supplies a cooling gas such as helium (He) to the space between the chip W placed on the placement surface 11a and the bottom surface 13b of the recess 13. The supplied cooling gas cools the chip W placed on the placement surface 11a. In this embodiment, the case where only one air hole 8 is formed in the central portion of the electrostatic chuck device 1A is described, but the number of air holes 8 can be selected arbitrarily, and a plurality of air holes 8 can also be provided in the electrostatic chuck device 1A.

[0047] (Cylindrical component)

[0048] The tubular component 51 has a cylindrical shape extending in the thickness direction. The upper end of the tubular component 51 is annular when viewed from above, for example. In the following description, the radial direction centered on the tubular component 51 is sometimes referred to as "radial direction", and the circumferential direction centered on the tubular component 51 is sometimes referred to as "circumferential direction". The tubular component 51 of this embodiment is made of a conductive material. In addition, the so-called "conductivity" here refers to a resistivity of 0.5Ω·m or less. Therefore, the tubular component is formed of a component with a resistivity of 0.5Ω·m or less. The preferred range of the resistivity of the material constituting the tubular component 51 can be selected as needed, and 1.0×10 -8 ~1.0×10 -3 Ω·m、1.0×10 -8 ~1.0×10 -6 Ω·m、1.0×10 -7 ~1.0×10 -4 Ω·m、1.0×10-5 ~1.0×10 -3 Ω·m、1.0×10 -4 ~1.0×10 -2 Ω·m、1.0×10 -3 The material forming the cylindrical member 51 can be arbitrarily selected, and examples thereof include molybdenum, tungsten, tantalum, carbon, compounds containing these, and ceramics, but are not limited to these examples.

[0049] The cylindrical member 51 surrounds the air hole 8 from the radially outer side. The cylindrical member 51 is disposed within the hole of the dielectric substrate 11. The outer surface of the cylindrical member 51 may be in contact with the dielectric substrate 11, or may be bonded to the dielectric substrate 11 via an adhesive, etc. In this embodiment, no other components are disposed within the cylindrical member 51; the inner surface of the cylindrical member 51 constitutes the inner surface of the air hole 8. However, another cylindrical component, such as an insulating insulator, may be disposed within the cylindrical member 51. In this case, the inner surface of the insulator constitutes the air hole 8.

[0050] The cylindrical member 51 is positioned so as to penetrate the bottom surface 13b of the recessed portion 13 of the dielectric substrate 11 and the lower surface 11b of the dielectric substrate 11. Therefore, the upper end 51t of the cylindrical member 51 in this embodiment is positioned approximately flush with the bottom surface 13b in the thickness direction and is exposed upward from the bottom surface 13b. Furthermore, the lower end 51b of the cylindrical member 51 is positioned approximately flush with the lower surface 11b in the thickness direction.

[0051] (Adsorption electrode, bias electrode and shielding layer)

[0052] The adsorption electrode 30, bias electrode 40, and shield layer 55A are electrodes and conductive components embedded in the dielectric substrate 11 in a layered manner. The adsorption electrode 30, bias electrode 40, and shield layer 55A are electrically conductive. Specifically, they are formed from a material with a resistivity of 0.5 Ω·m or less. The adsorption electrode 30, bias electrode 40, and shield layer 55A are arranged in this order from top to bottom within the dielectric substrate 11.

[0053] The adsorption electrode 30 is located inside the dielectric substrate 11. The adsorption electrode 30 extends in a layer along a plane perpendicular to the thickness direction of the dielectric substrate 11. The adsorption electrode 30 can have any desired shape. A first hole 30a is appropriately provided in the adsorption electrode 30 for the tubular member 51 to pass through. The inner diameter of the first hole 30a is sufficiently larger than the outer diameter of the tubular member 51. The inner edge of the first hole 30a is spaced apart from the outer circumferential surface of the tubular member 51. The provision of the first hole 30a prevents the adsorption electrode 30 and the tubular member 51 from contacting each other.

[0054] The adsorption electrode 30 is arranged on the lower side relative to the supporting surface 11a and the bottom surface 13b in a manner maintaining a predetermined size therewith. The adsorption electrode 30 is connected to the DC power supply 101 via the first power supply portion 31 extending downward. The adsorption electrode 30 generates an electrostatic adsorption force by the DC current supplied from the DC power supply 101, and adsorbs the wafer W to the supporting surface 11a. In addition, the adsorption electrode 30 is not limited to a monopolar adsorption electrode, but may also be a bipolar adsorption electrode consisting of two electrodes in a semicircular shape when viewed from above. In addition, when viewed from the thickness direction, the adsorption electrode 30 may be provided only on a portion of the circumference centered on the cylindrical part 51. In addition, when viewed from the thickness direction, a plurality of adsorption electrodes 30 may be provided at intervals along the circumference centered on the cylindrical part 51.

[0055] The bias electrode 40 is positioned below the adsorption electrode 30 (on the side opposite the mounting surface 11a), spaced apart from the adsorption electrode 30. The bias electrode 40 extends in a layer along a plane perpendicular to the thickness direction of the dielectric substrate 11. The bias electrode 40 can have any desired shape. The bias electrode 40 is connected to the AC power supply 102 via a second power supply portion 41 extending downward.

[0056] The bias electrode 40 is appropriately provided with a second hole portion 40a for the cylindrical member 51 to pass through and a third hole portion 40h for the first power supply portion 31 to pass through. The inner diameter of the second hole portion 40a is sufficiently large relative to the outer diameter of the cylindrical member 51. The inner edge of the second hole portion 40a is arranged to be spaced apart from the outer peripheral surface of the cylindrical member 51. In the present embodiment, the inner diameter of the second hole portion 40a is substantially equal to the inner diameter of the first hole portion 30a. Similarly, the inner diameter of the third hole portion 40h is sufficiently large relative to the outer diameter of the first power supply portion 31. The inner edge of the third hole portion 40h is arranged to be spaced apart from the outer peripheral surface of the first power supply portion 31. The shapes of the second hole portion 40a and the third hole portion 40h can be arbitrarily selected, for example, they can be circular when viewed from above.

[0057] In this embodiment, 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 position when viewed in the thickness direction. Thus, in this embodiment, the bias electrode 40 is positioned so as to cover substantially the entire portion of the adsorption electrode 30 from below. Furthermore, when viewed in the thickness direction, it suffices for at least a portion of the bias electrode 40 to overlap with the adsorption electrode 30. That is, when viewed in the thickness direction, at least a portion of the bias electrode 40 overlaps with the adsorption electrode 30. In this embodiment, the entire bias electrode 40 overlaps with the adsorption electrode 30 when viewed in the thickness direction.

[0058] The shield layer 55A is disposed spaced apart from the adsorption electrode 30 and the bias electrode 40 below (on the side opposite to the mounting surface 11a) within the dielectric substrate 11. The shield layer 55A extends in a layer along a plane perpendicular to the thickness direction of the dielectric substrate 11.

[0059] The shielding layer 55A contacts the outer circumferential surface of the cylindrical member 51 and is electrically connected to the cylindrical member 51. The shielding layer 55A extends radially outward from the outer circumferential surface of the cylindrical member 51. In this embodiment, the shielding layer 55A is formed into a flange shape that extends annularly along the circumference. Furthermore, the shielding layer 55A may have any shape. The shielding layer 55A is preferably a continuous annular shape, but other shapes are also possible. For example, the shielding layer 55A may be composed of multiple sections of any shape, such as a fan-shaped or roughly fan-shaped section. The shielding layer 55A may also be provided only on a portion of the circumference. For example, the shielding layer 55A may be provided as a shielding layer 55A composed of multiple sections spaced apart in the circumferential direction. In this case, multiple shielding layers 55A may extend radially from the outer circumferential surface of the cylindrical member 51. The number of shielding layer 55A sections may be, for example, 3 to 6, 6 to 12, 12 to 24, or 24 to 48. When there are multiple shielding layers 55A, their shapes and sizes may be the same. The distance between adjacent portions can also be arbitrarily selected. In the present embodiment, when viewed in the thickness direction, the entire outer edge 55 s at the radially outer end of the shield layer 55A overlaps with the bias electrode 40 .

[0060] The adsorption electrode 30, bias electrode 40, and shield layer 55A are formed of any material, but are preferably composed of a composite material of an insulating material and a conductive material. The insulating material contained in the composite material is not particularly limited, but is preferably at least one selected from the group consisting of aluminum oxide (Al2O3), aluminum nitride (AlN), silicon nitride (Si3N4), yttrium (III) oxide (Y2O3), yttrium-aluminum-garnet (YAG), and SmAlO3. The conductive material contained in the composite material 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. The adsorption electrode 30, bias electrode 40, and shield layer 55A may be formed of the same material or different materials.

[0061] In addition, the cylindrical member 51 of this embodiment can be formed of the same material as the shielding layer 55A, or can be formed integrally with the shielding layer 55A. Alternatively, the cylindrical member 51 can be formed of a material different from that of the shielding layer 55A. Alternatively, the cylindrical member 51 can be made of a metal material and bonded to the shielding layer 55A on its outer circumference.

[0062] The adsorption electrode 30, bias electrode 40, and shield layer 55A may be preformed into a predetermined shape, or may be formed by three-dimensional printing, vapor deposition, etc. The adsorption electrode 30, bias electrode 40, and shield layer 55A may be sequentially embedded in each layer while laminating the dielectric substrate 11 in multiple layers.

[0063] (Cylindrical member and shielding layer extending outward from the cylindrical member)

[0064] In general, it is known that the chip W mounted on the mounting surface 11a releases secondary electrons from the lower surface side of the chip W due to the collision of the etching gas with the upper surface. In addition, the frequency of occurrence of this secondary electron release phenomenon has increased with the recent increase in etching power. If the secondary electrons released on the lower surface side of the chip W invade the interior of the pore 8, the cooling gas in the pore 8 is sometimes ionized, causing discharge in the pore 8. The inventors of the present invention have noticed that discharge accompanied by ionization of the cooling gas is likely to occur in the following cases: the potential difference in the thickness direction of the pore 8 between the lower surface of the chip W and the upper surface of the base 20 is large. As a result of the inventors of the present invention trying to reduce the potential difference in the pore 8, they came up with the structures of each embodiment and its modified examples.

[0065] In the electrostatic chuck plate 10A of this embodiment, an adsorption electrode 30 and a bias electrode 40 are disposed within the dielectric substrate 11. Therefore, a potential difference is generated in various parts within the dielectric substrate 11 due to the voltage applied to these electrodes 30 and 40. The electrostatic chuck plate 10A of this embodiment includes a conductive cylindrical member 51 that surrounds the air holes 8 of the dielectric substrate 11. This structure, since the air holes 8 are surrounded by the conductive cylindrical member 51, a large potential difference is less likely to occur within the air holes 8, thereby suppressing discharge of the cooling gas within the air holes 8. In particular, in this embodiment, the cylindrical member 51 is disposed radially inward of the electrostatic chuck plate 10A relative to the adsorption electrode 30 and the bias electrode 40. Consequently, the electric field directed radially inward from the adsorption electrode 30 and the bias electrode 40 toward the electrostatic chuck plate 10A can be suppressed from reaching the interior of the air holes 8.

[0066] However, even when the cylindrical member 51 is provided to suppress the potential difference within the air hole 8, there is a risk that the potential difference will increase in the area below the cylindrical member 51, which is located within the air hole 8. In contrast, the electrostatic chuck plate 10A of this embodiment includes a conductive shield layer 55A. This shield layer 55A is located within the dielectric substrate 11 on the side (below) opposite the mounting surface 11a, relative to the adsorption electrode 30 and the bias electrode 40, and extends radially outward from the outer circumference of the cylindrical member 51. This allows the electric field to avoid the shield layer 55A, and the potential difference below the cylindrical member 51 is less likely to increase. As a result, a large potential difference can be suppressed within the air hole 8 below the cylindrical member 51, and discharge of the cooling gas within the air hole 8 can be suppressed.

[0067] Figure 2 and Figure 3 Graphs showing simulation results for illustrating the advantages of the electrostatic chuck device 1A according to this embodiment. Figure 2 FIG. 1 shows an electrostatic chuck device 1P of a comparative example that does not have the shield layer 55A. Figure 3 The electrostatic chuck device 1A of the example of the present embodiment has a shield layer 55A compared to the electrostatic chuck device 1A of the comparative example. Figure 2 and Figure 3 , the simulation results of the equipotential lines of the electric field generated by the adsorption electrode 30 and the bias electrode 40 are schematically shown.

[0068] exist Figure 2 In the electrostatic chuck device 1P of the comparative example shown, the equipotential lines are concentrated and arranged vertically on the lower side of the cylindrical member 51, and it can be confirmed that the potential difference is large on the lower side of the cylindrical member 51. Figure 3 In the electrostatic chuck device 1A of the illustrated embodiment, most of the equipotential lines extending from the end of the bias electrode 40 extend along the upper surface of the shield layer 55A and the inner circumferential surface of the tubular member 51 to the upper end of the electrostatic chuck plate 10A. Furthermore, a portion of the equipotential lines extending from the end of the bias electrode 40 extends in a significantly circuitous manner outside the outer edge 55s of the shield layer 55A and passes through the underside of the tubular member 51. Figure 3 The number of equipotential lines arranged on the lower side of the cylindrical member 51 in the electrostatic chuck device 1A of the embodiment is less than Figure 2 The number of equipotential lines arranged on the lower side of the cylindrical member 51 in the electrostatic chuck device 1P of the comparative example is Figure 3 In the electrostatic chuck device 1A of the embodiment, it was confirmed that the potential difference on the lower side of the tubular member 51 was reduced.

[0069] The shielding layer 55A of this embodiment is arranged on the side opposite to the support surface 11a (lower side) relative to the adsorption electrode 30 and the bias electrode 40. That is, when viewed from a cross-section, the distance from the support surface 11a to the shielding layer 55A is greater than the distance from the support surface 11a to the adsorption electrode 30 or the bias electrode 40. According to this structure, the shielding layer 55A can be arranged between the adsorption electrode 30 and the bias electrode 40 and the lower end of the cylindrical member 51 in the thickness direction. With this structure, as shown in FIG. Figure 3 As shown in FIG. 1 , the equipotential lines extending from the ends of the adsorption electrode 30 and the bias electrode 40 can be largely detoured at a position above the lower end of the tubular member 51. As a result, the above-mentioned Figure 2 As shown, the equipotential lines are concentrated on the lower side of the cylindrical member 51. As a result, the potential difference on the lower side of the cylindrical member 51 can be effectively suppressed. Furthermore, the electric field generated by applying voltage to the adsorption electrode 30 and the bias electrode 40 can reach the upper side of the dielectric substrate 11 without being blocked by the shield layer 55A, so that the electric field is effectively exerted on the upper side of the dielectric substrate 11.

[0070] In the electrostatic chuck plate 10A of this embodiment, the shield layer 55A preferably overlaps at least a portion of the bias electrode 40 when viewed in the thickness direction. Overlapping the shield layer 55A with the bias electrode 40 allows the equipotential lines extending from the end of the bias electrode 40 to more reliably detour, effectively suppressing a potential difference on the lower side of the tubular member 51. This structure facilitates the detour of the equipotential lines at least in the portion where the shield layer 55A overlaps the bias electrode 40. Consequently, a large potential difference is less likely to occur on the lower side of the tubular member 51, and discharge of the cooling gas in the air holes 8 can be suppressed. The length (distance) of the portion where the shield layer 55A overlaps the bias electrode 40 when viewed from above can be arbitrarily selected. For example, the length of the overlapping portion can be 0 to 0.1 times, 0.1 to 0.5 times, 0.3 to 0.8 times, or 0.5 to 1.0 times the length (distance) from the tubular member 51 to the radial end of the shield layer 55A, but is not limited to these examples. For example, the shield layer 55A does not need to overlap the bias electrode 40. Furthermore, the length (distance) from the cylindrical member 51 to the radial end of the shield layer 55A can be arbitrarily selected. For example, the diameter of the shield layer 55A can be 0.5 to 2 mm, 1 to 3 mm, 2 to 5 mm, 4 to 8 mm, or 5 to 10 mm, but is not limited to these examples.

[0071] In the electrostatic chuck plate 10A of this embodiment, the shield layer 55A is formed into a flange shape that extends annularly around the cylindrical member 51. This flange shape of the shield layer 55A facilitates the detour of equipotential lines along the entire circumference of the cylindrical member 51 due to the flange of the shield layer 55A, thus preventing a large potential difference on the lower side of the cylindrical member 51. As a result, discharge of the cooling gas within the air holes 8 can be suppressed.

[0072] In the electrostatic chuck plate 10A of this embodiment, the entire outer edge 55s of the shield layer 55A overlaps the bias electrode 40 when viewed in the thickness direction. This structure allows the equipotential lines extending from the end of the bias electrode 40 to easily detour outside the shield layer 55A over the entire outer edge 55s of the shield layer 55A. This reduces the likelihood of a large potential difference occurring on the lower side of the tubular member 51, and suppresses discharge of cooling gas in the air holes 8.

[0073] In the electrostatic chuck plate 10A of this embodiment, the upper end (one end) 51t of the cylindrical member 51 extends to the mounting surface 11a side of the dielectric substrate 11, while the lower end (the other end) 51b of the cylindrical member 51 extends to the lower surface 11b of the dielectric substrate 11, which faces the side opposite the mounting surface 11a. Here, "extending to the mounting surface 11a side of the dielectric substrate 11" refers to extending to the end surface (bottom surface 13b in this embodiment) of the dielectric substrate 11 on the mounting surface 11a side. This structure allows the cylindrical member 51 to surround the area of ​​the air hole 8 located on the dielectric substrate 11, thereby suppressing discharge of cooling gas within this area.

[0074] [Second embodiment]

[0075] Figure 4 This is a cross-sectional view of an electrostatic chuck device according to a second embodiment. The electrostatic chuck device 1B of this embodiment differs from the electrostatic chuck device 1A described above in the structure of the tubular member 52; otherwise, the structure is the same as the electrostatic chuck device 1A. Therefore, the description will focus primarily on the tubular member 52, and description of the same structures as the electrostatic chuck device 1A will be omitted.

[0076] Figure 4 The electrostatic chuck device 1B shown includes an electrostatic chuck plate 10B and a base 20. The electrostatic chuck plate 10B includes a dielectric substrate 11, a cylindrical member 52, an adsorption electrode 30, a bias electrode 40, and a shield layer 55A.

[0077] The cylindrical member 52 is cylindrical and extends in the thickness direction. It is positioned so as to penetrate the bottom surface 13b of the recessed portion 13 of the dielectric substrate 11 and the base bottom surface 20b of the base 20. In other words, the upper end 52t of the cylindrical member 52 is positioned at the same height as the bottom surface 13b in the thickness direction and is exposed upward from the bottom surface 13b. The lower end (the other end) 52b of the cylindrical member 52 is positioned at the same height as the base bottom surface 20b in the thickness direction and is exposed downward from the base bottom surface 20b.

[0078] The cylindrical member 52 of this embodiment is grounded via the ground wire 103. This configuration can suppress the generation of a potential difference in the thickness direction of the cylindrical member 52, and can suppress abnormal discharge inside the pores 8.

[0079] The electrostatic chuck device 1B of this embodiment includes a base 20 that supports the electrostatic chuck plate 10B from the side opposite to the mounting surface 11a. The cylindrical member 52 is in contact with the base 20. This structure eliminates any gap between the cylindrical member 52 and the base 20. Consequently, it is possible to suppress the electric field from concentrating on the lower side of the cylindrical member 52 and the upper side of the base 20. This prevents a large potential difference between the lower side of the cylindrical member 52 and the upper side of the base 20, which are located inside the air hole 8, and effectively suppresses discharge within the air hole 8.

[0080] In the electrostatic chuck device 1B of this embodiment, the air hole 8 extends through the base 20 in the thickness direction. The upper end (one end) 52t of the cylindrical member 52 extends to the mounting surface 11a side of the dielectric substrate 11. The lower end (the other end) 52b of the cylindrical member 52 extends to the lower surface of the base 20 facing the side opposite to the mounting surface 11a. With this structure, the cylindrical member 52 surrounds not only the interior of the dielectric substrate 11 within the air hole 8, but also the area within the base 20, thereby suppressing the discharge of cooling gas throughout this entire area.

[0081] (First Modification of the Implementation)

[0082] Figure 5 This is a cross-sectional view of an electrostatic chuck device according to a first modification of the embodiment. This modification, electrostatic chuck device 1C, differs from electrostatic chuck device 1A according to the first embodiment only in the structure of the tubular member. Components identical to those in the first embodiment are designated by the same reference numerals, and their descriptions are omitted.

[0083] like Figure 5 As shown, the electrostatic chuck device 1C of this modification includes an electrostatic chuck plate 10C and a base 20, similarly to the above embodiment. The electrostatic chuck plate 10C also includes a dielectric substrate 11, a cylindrical member 53, an adsorption electrode 30, a bias electrode 40, and a shield layer 55A.

[0084] The cylindrical member 53 of this modified example surrounds the air hole 8. The upper end (one end) 53t of the cylindrical member 53 is positioned at the same height as the bottom surface 13b in the thickness direction. The lower end (the other end) 53b of the cylindrical member 53 is positioned above the lower surface of the dielectric substrate 11 in the thickness direction. This lower end 53b is formed at the same height as the lower surface of the shielding layer 55A in the thickness direction. The cylindrical member 53 and the shielding layer 55A do not contact the adhesive layer 25.

[0085] The electrostatic chuck device 1C having the above-described structure includes the bias electrode 40 and the shield layer 55A similarly to the electrostatic chuck device 1A of the first embodiment, thereby also being able to suppress abnormal discharge inside the air hole 8 .

[0086] (Second Modification of the Implementation Method)

[0087] Figure 6 This is a cross-sectional view of an electrostatic chuck device according to a second modification of the embodiment. The electrostatic chuck device 1D of this modification differs from the electrostatic chuck device 1A of the first embodiment only in the structure of the shield layer 55D. Components identical to those of the first embodiment are denoted by the same reference numerals, and their descriptions are omitted.

[0088] like Figure 6 As shown, the electrostatic chuck device 1D of this modification includes an electrostatic chuck plate 10D and a base 20, similar to the above-described embodiment. Furthermore, the electrostatic chuck plate 10D includes a dielectric substrate 11, a cylindrical member 51, an adsorption electrode 30, a bias electrode 40, and a shield layer 55D. In this modification, the lower surface of the shield layer 55D is formed at the same height as the lower surface 11b of the dielectric substrate 11 and is in contact with the adhesive layer 25.

[0089] The electrostatic chuck device 1D having the above-described structure includes the bias electrode 40 and the shield layer 55D similarly to the electrostatic chuck device 1A of the first embodiment, thereby also being able to suppress abnormal discharge inside the air hole 8 .

[0090] While the embodiments and modifications of the present invention have been described above, the various structures and combinations thereof in the embodiments and modifications are merely examples, and additions, omissions, substitutions, and other modifications to the structures are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to the embodiments.

[0091] Label Description

[0092] 1A~1D, 1P-Electrostatic chuck device

[0093] 8-Stomach

[0094] 10A~10D-Electrostatic chuck plate (electrostatic chuck component)

[0095] 11-Dielectric substrate

[0096] 11a-Loading surface

[0097] 11b-lower surface

[0098] 12-Protrusion

[0099] 13-Concave

[0100] 13b-Bottom

[0101] 20-Abutment

[0102] 20b-Abutment bottom surface

[0103] 20t-upper surface

[0104] 25-adhesive layer

[0105] 30-Adsorption electrode

[0106] 30a-1st hole

[0107] 30b-outer periphery

[0108] 40-Bias electrode

[0109] 40a-Second hole

[0110] 40b-outer periphery

[0111] 40h-3rd hole

[0112] 41-Second Power Supply Department

[0113] 51~53-Cylindrical parts

[0114] 51b, 52b, 53b-lower end (other end)

[0115] 51t, 52t, 53t-upper end (one end)

[0116] 55A, 55D-shielding layer

[0117] 55s-outer edge

[0118] 101-DC Current

[0119] 102-AC

[0120] 103-Ground wire

[0121] O-Center Axis

[0122] W-wafer (plate sample)

Claims

1. An electrostatic chuck component, comprising: A plate-shaped dielectric substrate is provided with a placement surface for placing the plate-shaped sample and air holes penetrating in the thickness direction; an adsorption electrode, disposed inside the dielectric substrate; a bias electrode disposed inside the dielectric substrate; a cylindrical component surrounding the air hole and having electrical conductivity; and The shield layer is disposed inside the dielectric substrate on the opposite side of the placement surface relative to the adsorption electrode and the bias electrode, extends from the outer peripheral surface of the cylindrical member toward the outside in the radial direction centered on the cylindrical member, and has conductivity.

2. The electrostatic chuck component according to claim 1, wherein: When viewed in the thickness direction, at least a portion of the shielding layer overlaps with the bias electrode.

3. The electrostatic chuck component according to claim 1, wherein: The shield layer is formed in a flange shape extending annularly along a circumferential direction centered on the cylindrical member.

4. The electrostatic chuck component according to claim 3, wherein: When viewed in the thickness direction, the entire outer edge of the shielding layer overlaps with the bias electrode.

5. The electrostatic chuck assembly according to claim 1, wherein: One end of the cylindrical member extends to the mounting surface side of the dielectric substrate, The other end of the cylindrical member extends to the lower surface of the dielectric substrate facing the side opposite to the mounting surface.

6. The electrostatic chuck assembly according to claim 1, wherein: The cylindrical member is grounded.

7. An electrostatic chuck device comprising: The electrostatic chuck component according to any one of claims 1 to 6; and a base supporting the electrostatic chuck component from a side opposite to the mounting surface, The cylindrical member is in contact with the base.

8. The electrostatic chuck device according to claim 7, wherein: The pores penetrate the base along the thickness direction, One end of the cylindrical member extends to the mounting surface side of the dielectric substrate, The other end of the cylindrical member extends to the lower surface of the base facing the side opposite to the placement surface.

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