Electrostatic chuck member and electrostatic chuck device

Abstract

To provide an electrostatic chuck device capable of suppressing abnormal discharge inside a gas hole.SOLUTION: An electrostatic chuck comprises: a plate-shaped dielectric substrate with a mounting surface on which a plate-shaped sample is placed and gas holes penetrating in the thickness direction; an adsorption electrode placed inside the dielectric substrate; a bias electrode placed inside the dielectric substrate; a conductive tubular member surrounding the gas hole; and a conductive shield layer located inside the dielectric substrate on the opposite side of the dielectric substrate to the adsorption electrode and a bias electrode from the mounting surface side, and extending from the outer circumference of the tubular member to the outside of the radial direction around the tubular member.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electrostatic chuck member and an electrostatic chuck device. [Background technology]

[0002] Electrostatic chuck devices that support a substrate such as a semiconductor wafer are known. For example, Patent Document 1 describes such an electrostatic chuck device having a structure in which a sample stage that electrostatically attracts an object to be processed has a plurality of gas holes that supply a heat transfer gas between the object to be processed and the sample stage to control the temperature of the object to be processed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-182763 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the electrostatic chuck device as described above, the through hole for gas supply may become the starting point of discharge that leads to damage to the semiconductor wafer. In recent years, plasma etching devices for semiconductor manufacturing have become increasingly powerful for deep hole processing due to the increasing number of semiconductor layers. For this reason, it is necessary to suppress the occurrence of abnormal discharge inside the gas hole.

[0005] An object of the present invention is to provide an electrostatic chuck device capable of suppressing abnormal discharge inside a gas hole. [Means for solving the problem]

[0006] The present invention includes the following inventions [1] to [8]. It is also preferable to combine two or more of the following inventions as necessary. [1] An electrostatic chuck member comprising: a plate-shaped dielectric substrate having a mounting surface on which a plate-shaped sample is placed and a gas hole penetrating in a thickness direction; an adsorption electrode disposed inside the dielectric substrate; a bias electrode disposed inside the dielectric substrate; a conductive cylindrical member surrounding the gas hole; and a conductive shielding layer disposed inside the dielectric substrate on the opposite side of the mounting surface with respect to the adsorption electrode and the bias electrode, the conductive shielding layer extending radially outward from an outer peripheral surface of the cylindrical member centered on the cylindrical member. [2] The electrostatic chuck member according to [1], wherein, when viewed in the thickness direction, at least a portion of the shield layer overlaps with the bias electrode. [3] The electrostatic chuck member according to [1] or [2], wherein the shield layer is formed in a flange shape extending annularly in a circumferential direction centered on the cylindrical member. [4] The electrostatic chuck member according to [3], wherein, when viewed from the thickness direction, the entire outer edge of the shield layer overlaps with the bias electrode. [5] An electrostatic chuck member described in any one of [1] to [4], wherein one end of the cylindrical member extends to the mounting surface side of the dielectric substrate, and the other end of the cylindrical member extends to a bottom surface facing opposite the mounting surface side of the dielectric substrate. [6] The electrostatic chuck member according to any one of [1] to [5], wherein the cylindrical member is grounded. [7] An electrostatic chuck device comprising: the electrostatic chuck member according to any one of [1] to [6]; and a base supporting the electrostatic chuck member from an opposite side to the mounting surface, wherein the cylindrical member is in contact with the base. [8] An electrostatic chuck device as described in [7], wherein the gas hole penetrates the base in 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 an underside facing the opposite side to the mounting surface side of the base. Effect of the Invention

[0007] According to one aspect of the present invention, there is provided an electrostatic chuck device capable of suppressing abnormal discharge inside a gas hole. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view of an electrostatic chuck device according to a first embodiment. [Diagram 2] FIG. 2 is a diagram showing equipotential lines of an electrostatic chuck device of a comparative example. [Diagram 3] FIG. 3 is a diagram showing equipotential lines of the electrostatic chuck device of the embodiment. [Figure 4] FIG. 4 is a cross-sectional view of an electrostatic chuck device according to the second embodiment. [Diagram 5] FIG. 5 is a cross-sectional view of an electrostatic chuck device according to a first modified example of the embodiment. [Figure 6] FIG. 6 is a cross-sectional view of an electrostatic chuck device according to a second modified example of the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, embodiments of the electrostatic chuck device of the present invention will be described with reference to the drawings. In all of the following drawings, the dimensions and ratios of the components may be appropriately changed in order to make the drawings easier to understand.

[0010] [First embodiment] (Electrostatic chuck device as a whole) FIG. 1 is a cross-sectional view of an electrostatic chuck device according to the present embodiment. An electrostatic chuck device 1A shown in FIG. 1 is placed in a vacuum chamber of a plasma processing device with a mounting surface 11a on which a wafer (plate-shaped sample) W is placed facing upward. In each drawing, a Z-axis is shown to explain the reference of the electrostatic chuck device. The Z-axis direction is, for example, a 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 with respect to the vertical direction is an example, and other arrangements may be used.

[0011] The electrostatic chuck device 1A includes an electrostatic chuck plate (electrostatic chuck member) 10A that attracts and supports a plate-like sample such as a wafer W, and a base 20 that supports the electrostatic chuck plate 10A.

[0012] (Base) The base 20 is made of a thick, disk-shaped metal member. The base 20 supports the electrostatic chuck plate 10A from the lower side (the opposite side to the mounting surface 11a). There is no particular limitation on the material constituting the base 20 as long as it is a metal having excellent thermal conductivity, electrical conductivity, and workability, or a composite material containing such a metal, and for example, aluminum, an aluminum alloy, copper, a copper alloy, stainless steel, etc. are preferably used. The base 20 of this embodiment may be a water-cooled base having a flow path (not shown) therein for circulating a coolant such as water.

[0013] The upper surface 20t of the base 20 is adhered to the lower surface 11b of the dielectric substrate 11 via an adhesive layer 25. The adhesive layer 25 is made of, for example, a heat-resistant resin such as polyimide resin, silicone resin, or epoxy resin, or an insulating sheet-like or film-like adhesive resin.

[0014] (Electrostatic chuck plate) The electrostatic chuck plate 10A includes a dielectric substrate 11, a cylindrical member 51, an attraction electrode 30, a bias electrode 40, and a shield layer 55A. The cylindrical member 51, the attraction electrode 30, the bias electrode 40, and the shield layer 55A are each embedded in the dielectric substrate 11.

[0015] (Dielectric substrate) The dielectric substrate 11 is a plate-like member that is circular in plan view. In this specification, the thickness direction of the dielectric substrate 11 may be simply referred to as the "thickness direction". In this specification, the electrostatic chuck device will be described with the side in the thickness direction on which the wafer W is mounted being referred to as the "upper side" and the opposite side being referred to as the "lower side". In this specification, the "upper side" and the "lower side" indicate examples of the posture of the electrostatic chuck device when in use, and do not limit the posture of the electrostatic chuck device when in use.

[0016] The dielectric substrate 11 is made of a composite sintered body having mechanical strength and durability against corrosive gas and its plasma. As a dielectric material constituting the dielectric substrate 11, ceramics having mechanical strength and durability against corrosive gas and its plasma are preferably used. As a ceramic constituting the dielectric substrate 11, for example, an aluminum oxide sintered body, an aluminum nitride sintered body, an aluminum oxide-silicon carbide composite sintered body, etc. are preferably used.

[0017] The upper surface of the dielectric substrate 11 is configured with a mounting surface 11a on which the wafer W is placed. That is, the dielectric substrate 11 is provided with the mounting surface 11a on which the wafer W is placed. In this embodiment, a plurality of protrusions 12 are formed at predetermined intervals on the upper surface of the dielectric substrate 11. The tip surfaces of the plurality of protrusions 12 form the mounting surface 11a. The dielectric substrate 11 is formed with recesses 13 between adjacent protrusions 12, which are recessed downward with respect to the mounting surface 11a. The bottom surface 13b of the recesses 13 faces upward (toward the wafer W).

[0018] The dielectric substrate 11 is provided with a gas hole 8. The gas hole 8 penetrates the dielectric substrate 11 in the thickness direction. The gas hole 8 is circular when viewed in the thickness direction. The gas hole 8 is connected to a gas supply device (not shown). The gas hole 8 supplies a cooling gas such as helium (He) to a 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, a case will be described in which only one gas hole 8 is formed in the center of the electrostatic chuck device 1A, but a plurality of gas holes 8 may be provided in the electrostatic chuck device 1A.

[0019] (Cylindrical member) The cylindrical member 51 has a cylindrical shape extending in the thickness direction. In the following description, the radial direction around the cylindrical member 51 may be simply referred to as the "radial direction", and the circumferential direction around the cylindrical member 51 may be simply referred to as the "circumferential direction". The cylindrical member 51 of this embodiment is made of a conductive material. Here, "conductive" means that the resistivity is 0.5 Ωm or less. Therefore, the cylindrical member is made of a material with a resistivity of 0.5 Ωm or less.

[0020] The cylindrical member 51 surrounds the gas hole 8 from the radial outside. In this embodiment, no other members are disposed inside the cylindrical member 51, and the inner surface of the cylindrical member 51 forms the inner surface of the gas hole 8. However, other cylindrical members such as insulating insulators may be disposed inside the cylindrical member 51. In this case, the inner surface of the insulator forms the gas hole 8.

[0021] The cylindrical member 51 is disposed so as to penetrate the bottom surface 13b of the recess 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 disposed at approximately the same position as the bottom surface 13b in the thickness direction and is exposed upward from the bottom surface 13b. Also, the lower end 51b of the cylindrical member 51 is disposed at approximately the same position as the lower surface 11b in the thickness direction.

[0022] (Adsorption electrode, bias electrode, and shield layer) The chucking electrode 30, the bias electrode 40, and the shield layer 55A are electrodes and conductive members embedded in layers in the dielectric substrate 11. The chucking electrode 30, the bias electrode 40, and the shield layer 55A are conductive. That is, the chucking electrode 30, the bias electrode 40, and the shield layer 55A are made of a material having a resistivity of 0.5 Ωm or less. The chucking electrode 30, the bias electrode 40, and the shield layer 55A are arranged in this order from top to bottom in the dielectric substrate 11.

[0023] The chucking electrode 30 is located inside the dielectric substrate 11. The chucking electrode 30 extends in a layer shape along a plane perpendicular to the thickness direction of the dielectric substrate 11. The chucking electrode 30 is provided with a first hole 30a through which the cylindrical member 51 passes. The inner diameter of the first hole 30a is sufficiently larger than the outer diameter of the cylindrical member 51. The inner edge of the first hole 30a is disposed at a distance from the outer circumferential surface of the cylindrical member 51.

[0024] The chucking electrode 30 is disposed at a predetermined distance below the mounting surface 11a and the bottom surface 13b. The chucking electrode 30 is connected to a DC power source 101 via a first power supply unit 31 extending downward. The chucking electrode 30 generates an electrostatic chucking force by a DC current supplied from the DC power source 101, and chucking the wafer W to the mounting surface 11a. The chucking electrode 30 is not limited to a monopolar chucking electrode, and may be a bipolar chucking electrode consisting of two electrodes having a semicircular shape in a plan view. The chucking electrode 30 may be provided only in a part of the circumferential direction centered on the cylindrical member 51 as viewed in the thickness direction. The chucking electrode 30 may be provided in a plurality of electrodes spaced apart from each other in the circumferential direction centered on the cylindrical member 51 as viewed in the thickness direction.

[0025] The bias electrode 40 is disposed below (opposite the mounting surface 11a) the chucking electrode 30 with a gap therebetween. The bias electrode 40 extends in a layer shape along a plane perpendicular to the thickness direction of the dielectric substrate 11. The bias electrode 40 is connected to an AC power supply 102 via a second power supply part 41 extending downward.

[0026] The bias electrode 40 is provided with a second hole 40a through which the cylindrical member 51 passes, and a third hole 40h through which the first power supply unit 31 passes. The inner diameter of the second hole 40a is sufficiently larger than the outer diameter of the cylindrical member 51. The inner edge of the second hole 40a is disposed at a distance from the outer circumferential surface of the cylindrical member 51. In this embodiment, the inner diameter of the second hole 40a is approximately equal to the inner diameter of the first hole 30a. Similarly, the inner diameter of the third hole 40h is sufficiently larger than the outer diameter of the first power supply unit 31. The inner edge of the third hole 40h is disposed at a distance from the outer circumferential surface of the first power supply unit 31.

[0027] In this embodiment, the outer periphery 40b of the bias electrode 40 and the outer periphery 30b of the chucking electrode 30 are disposed at approximately the same position as seen in the thickness direction. As a result, in this embodiment, the bias electrode 40 is disposed so as to cover almost the entire chucking electrode 30 from below. Note that it is sufficient that at least a portion of the bias electrode 40 overlaps with the chucking electrode 30 as seen in the thickness direction. That is, at least a portion of the bias electrode 40 overlaps with the chucking electrode 30 as seen in the thickness direction. Moreover, the bias electrode 40 in this embodiment entirely overlaps with the chucking electrode 30 as seen in the thickness direction.

[0028] The shield layer 55A is disposed below (on the side opposite to the mounting surface 11a) the attraction electrode 30 and the bias electrode 40 within the dielectric substrate 11, with a gap therebetween. The shield layer 55A extends in a layered form along a plane perpendicular to the thickness direction of the dielectric substrate 11.

[0029] The shield layer 55A contacts the outer peripheral surface of the cylindrical member 51 and is electrically connected to the cylindrical member 51. The shield layer 55A extends radially outward from the outer peripheral surface of the cylindrical member 51. The shield layer 55A of this embodiment is formed in a flange shape extending annularly in the circumferential direction. The shield layer 55A may be provided only in a part of the circumferential direction. For example, a plurality of shield layers 55A may be provided at intervals in the circumferential direction. In this case, the plurality of shield layers 55A extend radially from the outer peripheral surface of the cylindrical member 51. In this embodiment, the radially outer outer edge 55s of the shield layer 55A entirely overlaps the bias electrode 40 when viewed in the thickness direction.

[0030] The attraction electrode 30, the bias electrode 40, and the shield layer 55A are made of a composite of an insulating material and a conductive material. The insulating material contained in this composite 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 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.

[0031] The cylindrical member 51 of the present embodiment may be integrally formed with the same material as the shield layer 55A. The cylindrical member 51 may be made of a metal material and may be joined to the shield layer 55A at the outer circumferential surface.

[0032] The attraction electrode 30, the bias electrode 40, and the shield layer 55A may be formed in advance into a predetermined shape, or may be formed by three-dimensional printing, deposition, etc. The attraction electrode 30, the bias electrode 40, and the shield layer 55A may be embedded in each layer in sequence while forming the dielectric substrate 11 by laminating the layers in a plurality of steps.

[0033] It is generally known that the wafer W mounted on the mounting surface 11a emits secondary electrons from the lower surface side of the wafer W when the etching gas collides with the upper surface. The frequency of occurrence of such a secondary electron emission phenomenon has been increasing with the recent increase in the power of etching. When the secondary electrons emitted to the lower surface side of the wafer W enter the inside of the gas hole 8, the cooling gas may be ionized in the gas hole 8, causing discharge in the gas hole 8. The present inventors have focused on the fact that discharge due to ionization of the cooling gas is likely to occur when the potential difference in the thickness direction in the gas hole 8 between the lower surface of the wafer W and the upper surface of the base 20 is large. The present inventors have attempted to reduce the potential difference in the gas hole 8 and have come up with the configurations according to the embodiments and their modified examples.

[0034] In the electrostatic chuck plate 10A of the present embodiment, the chucking electrode 30 and the bias electrode 40 are disposed inside the dielectric substrate 11, and therefore a potential difference occurs in each portion of the dielectric substrate 11 due to the voltage applied to these electrodes 30 and 40. The electrostatic chuck plate 10A of the present embodiment includes a conductive cylindrical member 51 surrounding the gas hole 8 of the dielectric substrate 11. According to this configuration, since the gas hole 8 is surrounded by the conductive cylindrical member 51, a large potential difference is unlikely to occur in the gas hole 8, and discharge of the cooling gas in the gas hole 8 can be suppressed. Particularly in the present embodiment, the cylindrical member 51 is disposed radially inward of the chucking electrode 30 and the bias electrode 40. Therefore, it is possible to suppress the electric field directed radially inward from the chucking electrode 30 and the bias electrode 40 from reaching the inside of the gas hole 8.

[0035] However, even when the potential difference inside the cylindrical member 51 is suppressed, there is a concern that the potential difference may become large in the region inside the gas hole 8 below the cylindrical member 51. In response to this, the electrostatic chuck plate 10A of the present embodiment is disposed on the opposite side (lower side) of the mounting surface 11a side with respect to the attraction electrode 30 and the bias electrode 40 inside the dielectric substrate 11, and includes a conductive shield layer 55A extending from the outer circumferential surface of the cylindrical member 51 to the outside in the radial direction centered on the cylindrical member 51. This allows an electric field to be formed avoiding the shield layer 55A, and the potential difference is unlikely to become large below the cylindrical member 51. As a result, it is possible to suppress the occurrence of a large potential difference inside the gas hole 8 below the cylindrical member 51, and to suppress the discharge of the cooling gas at the gas hole 8.

[0036] 2 and 3 are diagrams showing simulation results for illustrating the superiority of the electrostatic chuck device 1A of this embodiment. FIG. 2 shows an electrostatic chuck device 1P of a comparative example that does not have a shield layer 55A. Meanwhile, FIG. 3 shows an electrostatic chuck device 1A of an example of this embodiment, which has a shield layer 55A compared to the electrostatic chuck device 1A of the comparative example. FIG. 2 and FIG. 3 show schematic diagrams showing simulation results of equipotential lines of an electric field generated by the attraction electrode 30 and the bias electrode 40.

[0037] In the electrostatic chuck device 1P of the comparative example shown in FIG. 2, 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. On the other hand, in the electrostatic chuck device 1A of the embodiment shown in FIG. 3, most of the equipotential lines coming out 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 cylindrical member 51 to the upper end of the electrostatic chuck plate 10A. In addition, some of the equipotential lines coming out from the end of the bias electrode 40 extend so as to largely detour around the outside of the outer edge 55s of the shield layer 55A and pass through the lower side of the cylindrical member 51. 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 smaller than the equipotential lines arranged on the lower side of the cylindrical member 51 in the electrostatic chuck device 1P of the comparative example. From this, it can be confirmed that the potential difference is small on the lower side of the cylindrical member 51 in the electrostatic chuck device 1A of the embodiment.

[0038] The shield layer 55A of this embodiment is disposed on the opposite side (lower side) of the placement surface 11a side with respect to the chucking electrode 30 and the bias electrode 40. With this configuration, the shield layer 55A can be disposed between the chucking electrode 30 and the bias electrode 40 and the lower end of the cylindrical member 51 in the thickness direction. This allows the equipotential lines extending from the ends of the chucking electrode 30 and the bias electrode 40 to be largely detoured above the lower end of the cylindrical member 51, thereby preventing the equipotential lines from being concentrated and disposed below the cylindrical member 51. As a result, it is possible to effectively prevent the potential difference from becoming large below the cylindrical member 51. In addition, the electric field formed by applying a voltage to the chucking electrode 30 and the bias electrode 40 reaches the upper side of the dielectric substrate 11 without being blocked by the shield layer 55A, and the electric field can be effectively applied to the upper side of the dielectric substrate 11.

[0039] In the electrostatic chuck plate 10A of the present embodiment, it is preferable that at least a portion of the shield layer 55A overlaps with the bias electrode 40 when viewed in the thickness direction. By overlapping the shield layer 55A with the bias electrode 40, the equipotential lines extending from the end of the bias electrode 40 can be more reliably diverted, and the potential difference below the cylindrical member 51 can be effectively prevented from increasing. According to the above-mentioned configuration, the equipotential lines can be easily diverted at least in the portion where the shield layer 55A overlaps with the bias electrode 40. Therefore, the potential difference below the cylindrical member 51 can be prevented from increasing, and the discharge of the cooling gas at the gas hole 8 can be suppressed.

[0040] In the electrostatic chuck plate 10A of the present embodiment, the shield layer 55A is formed in a flange shape extending annularly in the circumferential direction centered on the cylindrical member 51. According to this configuration, by forming the shield layer 55A in the flange shape, it becomes easier to divert equipotential lines over the entire circumferential area of ​​the cylindrical member 51, and it is possible to prevent the potential difference from becoming large on the lower side of the cylindrical member 51. As a result, it is possible to suppress discharge of the cooling gas at the gas holes 8.

[0041] In the electrostatic chuck plate 10A of the present embodiment, when viewed from the thickness direction, the entire outer edge 55s of the shield layer 55A overlaps with the bias electrode 40. With this configuration, it is easy to divert equipotential lines extending from the end of the bias electrode 40 to the outside of the shield layer 55A over the entire outer edge 55s of the shield layer 55A. As a result, it is possible to make it difficult for a potential difference to increase on the lower side of the cylindrical member 51, and it is possible to suppress discharge of the cooling gas at the gas hole 8.

[0042] In the electrostatic chuck plate 10A of this embodiment, an upper end (one end) 51t of the cylindrical member 51 extends to the mounting surface 11a side of the dielectric substrate 11, and a lower end (the other end) 51b of the cylindrical member 51 extends to a lower surface 11b facing the opposite side to the mounting surface 11a side of the dielectric substrate 11. Here, "extending to the mounting surface 11a side of the dielectric substrate 11" means extending to an end face (bottom surface 13b in this embodiment) on the mounting surface 11a side of the dielectric substrate 11. With this configuration, the region of the gas hole 8 provided in the dielectric substrate 11 can be surrounded by the cylindrical member 51, and discharge of the cooling gas in this region can be suppressed.

[0043] [Second embodiment] 4 is a cross-sectional view of an electrostatic chuck device according to the second embodiment. Electrostatic chuck device 1B of the present embodiment is different from electrostatic chuck device 1A described above in that the configuration of cylindrical member 52 is different, and other configurations are common to electrostatic chuck device 1A. Therefore, the following mainly describes cylindrical member 52, and the description of the configurations common to electrostatic chuck device 1A will be omitted.

[0044] 4 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 attraction electrode 30, a bias electrode 40, and a shield layer 55A.

[0045] The tubular member 52 has a cylindrical shape extending in the thickness direction, and is disposed so as to penetrate the bottom surface 13b of the recess 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 tubular member 52 is disposed 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 tubular member 52 is disposed at the same height as the base bottom surface 20b in the thickness direction, and is exposed downward from the base bottom surface 20b.

[0046] The cylindrical member 52 of the present embodiment is grounded via a ground wire 103. With this configuration, the occurrence of a potential difference in the thickness direction inside the cylindrical member 52 can be suppressed, and abnormal discharge inside the gas hole 8 can be suppressed.

[0047] The electrostatic chuck device 1B of the present 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. With this configuration, no gap is generated between the cylindrical member 52 and the base 20, and therefore, it is possible to suppress the concentration of an electric field below the cylindrical member 52 and above the base 20. As a result, it is possible to suppress the potential difference from increasing in the region inside the gas hole 8, below the cylindrical member 52, and above the base 20, and it is possible to effectively suppress discharge inside the gas hole 8.

[0048] According to the electrostatic chuck device 1B of the present embodiment, the gas hole 8 penetrates the base 20 in the thickness direction. An upper end (one end) 52t of the cylindrical member 52 extends to the mounting surface 11a side of the dielectric substrate 11. A lower end (the other end) 52b of the cylindrical member 52 extends to the lower surface facing the side opposite to the mounting surface 11a side of the base 20. With this configuration, not only the inside of the dielectric substrate 11 but also the region of the gas hole 8 provided inside the base 20 can be surrounded by the cylindrical member 52, and discharge of the cooling gas can be suppressed in these entire regions.

[0049] (First Modification of the Embodiment) 5 is a cross-sectional view of an electrostatic chuck device according to a first modified example of the embodiment. Electrostatic chuck device 1C according to this modified example is different from electrostatic chuck device 1A according to the first embodiment described above only in the configuration of the cylindrical member. Note that the same components as those in the first embodiment described above are denoted by the same reference numerals and the description thereof will be omitted.

[0050] 5, like the above-described embodiment, an electrostatic chuck device 1C in this modification includes an electrostatic chuck plate 10C and a base 20. The electrostatic chuck plate 10C also includes a dielectric substrate 11, a cylindrical member 53, an attraction electrode 30, a bias electrode 40, and a shield layer 55A.

[0051] The cylindrical member 53 of this modification surrounds the gas hole 8. An upper end (one end) 53t of the cylindrical member 53 is disposed at the same height as the bottom surface 13b in the thickness direction. A lower end (the other end) 53b of the cylindrical member 53 is disposed 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 shield layer 55A in the thickness direction.

[0052] In the electrostatic chuck device 1C having the above configuration, similarly to the electrostatic chuck device 1A of the first embodiment, the bias electrode 40 and the shield layer 55A are provided, so that abnormal discharge inside the gas hole 8 can be suppressed.

[0053] (Second Modification of the Embodiment) 6 is a cross-sectional view of an electrostatic chuck device according to a second modified example of the embodiment. An electrostatic chuck device 1D according to this modified example is different from the electrostatic chuck device 1A according to the first embodiment described above only in the configuration of a shield layer 55D. Note that the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof will be omitted.

[0054] 6, an electrostatic chuck device 1D in this modification includes an electrostatic chuck plate 10D and a base 20, similar to the above-described embodiment. The electrostatic chuck plate 10D also includes a dielectric substrate 11, a cylindrical member 51, an attraction 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.

[0055] In the electrostatic chuck device 1D having the above configuration, similarly to the electrostatic chuck device 1A of the first embodiment, the bias electrode 40 and the shield layer 55D are provided, so that abnormal discharge inside the gas hole 8 can be suppressed.

[0056] Although the embodiments and modifications of the present invention have been described above, the configurations and combinations thereof in the embodiments and modifications are merely examples, and additions, omissions, substitutions, and other modifications of the configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to the embodiments. [Explanation of symbols]

[0057] 1A to 1D... electrostatic chuck device, 8... gas hole, 10A to 10D... electrostatic chuck plate (electrostatic chuck member), 11... dielectric substrate, 11a... mounting surface, 11b... lower surface, 20... base, 20b... base bottom surface, 30... chucking electrode, 40... bias electrode, 51 to 53... cylindrical member, 55A, 55D... shield layer, W... wafer (plate-shaped sample)

Claims

1. a plate-shaped dielectric substrate having a mounting surface on which a plate-shaped sample is placed and a gas hole penetrating in a thickness direction; an adsorption electrode disposed inside the dielectric substrate; A bias electrode disposed inside the dielectric substrate; a conductive cylindrical member surrounding the gas hole; a conductive shield layer disposed inside the dielectric substrate on a side opposite to the mounting surface side with respect to the attraction electrode and the bias electrode, the conductive shield layer extending from an outer circumferential surface of the cylindrical member to an outer side in a radial direction centered on the cylindrical member, Electrostatic chuck member.

2. When viewed from the thickness direction, at least a portion of the shield layer overlaps with the bias electrode. The electrostatic chuck member according to claim 1 .

3. The shield layer is formed in a flange shape extending annularly in a circumferential direction around the cylindrical member. The electrostatic chuck member according to claim 1 .

4. When viewed from the thickness direction, an entire outer edge of the shield layer overlaps with the bias electrode. The electrostatic chuck member according to claim 3 .

5. 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 a lower surface of the dielectric substrate facing away from the mounting surface side; The electrostatic chuck member according to claim 1 .

6. The cylindrical member is grounded. The electrostatic chuck member according to claim 1 .

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

8. The gas hole penetrates the base in 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 a lower surface of the base facing away from the mounting surface side.

8. The electrostatic chuck device of claim 7.

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