Electrostatic chuck device

Abstract

To provide an electrostatic chuck device that suppresses the occurrence of cracks in a ceramic layer due to a difference in thermal expansion between a substrate and a sleeve due to heat generated when the ceramic layer is formed.SOLUTION: An electrostatic chuck device 1 includes a substrate 10, a laminate 2 including at least an internal electrode 20 laminated on the substrate 10, and a ceramic layer 50 laminated on the upper surface of the laminate 2 in the thickness direction, and the substrate 10 has a through hole 60 provided so as to penetrate in the thickness direction, a sleeve 70 made of an insulating material is inserted into the through hole 60, and the sleeve 70 is joined to the through hole 60 via joining means 80 at the upper portion of the substrate 10 in the thickness direction.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] When manufacturing a semiconductor integrated circuit using a semiconductor wafer, or when manufacturing a liquid crystal panel using an insulating substrate such as a glass substrate or a film, it is necessary to adsorb and hold a base material such as a semiconductor wafer, a glass substrate, or an insulating substrate at a predetermined position. Therefore, in order to adsorb and hold these base materials, a mechanical chuck or a vacuum chuck by a mechanical method has been used. However, these holding methods have problems such as difficulty in uniformly holding the base material (the object to be adsorbed), inability to be used in a vacuum, and excessive rise in the temperature of the sample surface. Therefore, in recent years, an electrostatic chuck device that can solve these problems has been used for holding the object to be adsorbed.

[0003] An electrostatic chuck device mainly includes a conductive support member serving as an internal electrode and a dielectric layer made of a dielectric material covering the conductive support member. The object to be adsorbed can be adsorbed by this main part. When a voltage is applied to the internal electrode in the electrostatic chuck device to generate a potential difference between the object to be adsorbed and the conductive support member, an electrostatic attractive force is generated between the dielectric layers. As a result, the object to be adsorbed is supported substantially flat with respect to the conductive support member.

[0004] As a conventional electrostatic chuck device, an electrostatic chuck device in which an insulating organic film is laminated on an internal electrode to form a dielectric layer is known. Such an electrostatic chuck device is provided with a gas supply hole for cooling the ceramic layer with gas (see, for example, Patent Documents 1 and 2). An example of such an electrostatic chuck device is shown in FIG. 7. The electrostatic chuck device 500 shown in FIG. 7 includes a substrate 510, a laminate 540 including at least a plurality of internal electrodes 520 laminated on the substrate 510 and insulating organic films 530 provided on both sides in the thickness direction of the internal electrodes 520, and a ceramic layer 550 laminated on the upper surface in the thickness direction of the laminate 540. The internal electrodes 520 and the insulating organic films 530 are laminated on the substrate 510 via an adhesive layer 560. Further, a gas supply hole 600 for cooling the ceramic layer 550 with gas is provided so as to penetrate the substrate 510 and the laminate 540 in the thickness direction. A sleeve 570 made of an insulating material is inserted into the gas supply hole 600. The sleeve 570 is joined to the inner surface of the gas supply hole 600 via an adhesive 580 at the upper and lower portions in the thickness direction of the substrate 510. Further, the ceramic layer 550 is provided with a through hole 610 penetrating in the thickness direction thereof. The inner diameter (diameter perpendicular to the thickness direction) of the through hole 610 is smaller than the inner diameter (diameter perpendicular to the thickness direction) of the gas supply hole 600.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] The substrate 510 is made of a material with a relatively large coefficient of linear expansion such as aluminum, and the sleeve 570 is made of a material with a relatively small coefficient of linear expansion such as alumina. When forming the ceramic layer 550 on the laminate 540, a method of spraying the material constituting the ceramic layer 550 onto the entire outer surface of the laminate 540 is used. The heat generated by the spraying is transmitted to the substrate 510 and the sleeve 570. Then, due to the heat, the substrate 510 expands, but the sleeve 570 does not. When the sleeve 570 is joined to the gas supply holes 600 at the upper and lower parts in the thickness direction of the substrate 510, cracks may occur in the ceramic layer 550 (especially the ceramic layer 550 on the substrate 510 side) due to the thermal expansion of the substrate 510.

[0007] The present invention has been made in view of the above circumstances, and an object thereof is to provide an electrostatic chuck device that suppresses the occurrence of cracks in a ceramic layer due to the difference in thermal expansion between a substrate and a sleeve caused by heat generated when forming the ceramic layer. [Means for Solving the Problems]

[0008] The present invention has the following aspects. [1] An electrostatic chuck device comprising a substrate, a laminate including at least an internal electrode laminated on the substrate, and a ceramic layer laminated on the upper surface in the thickness direction of the laminate, wherein the substrate Made by spraying has a through hole provided penetrating in the thickness direction, a sleeve made of an insulating material is inserted into the through hole, and the sleeve is joined to the through hole via a joining means where a concave portion and a convex portion are joined at the upper part in the thickness direction of the substrate. And the laminate The area provided on the substrate of the laminate and the area provided on the laminate [2] An electrostatic chuck device comprising a substrate, a laminate including at least an internal electrode laminated on the substrate, and a ceramic layer laminated on the upper surface in the thickness direction of the laminate, wherein the substrate Made by spraying has a through hole provided penetrating in the thickness direction, a sleeve made of an insulating material is inserted into the through hole, and the sleeve is joined to the through hole via a joining means where a concave portion and a convex portion are joined at the upper part in the thickness direction of the substrate. And the laminate The area provided on the substrate of the laminate and the area provided on the laminateA sleeve made of an insulating material is inserted, and the sleeve is joined to the through hole through a joining means by which a male screw portion and a female screw portion are joined at an upper portion in the thickness direction of the substrate. An electrostatic chuck device characterized by this.

Effect of the Invention

[0009] According to the present invention, it is possible to provide an electrostatic chuck device that suppresses the occurrence of cracks in the ceramic layer due to the difference in thermal expansion between the substrate and the sleeve caused by the heat generated when forming the ceramic layer.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0011] Hereinafter, an electrostatic chuck device according to an embodiment to which the present invention is applied will be described. Note that in the drawings used in the following description, the dimensional ratios and the like of each component are not necessarily the same as the actual ones. Note that this embodiment is specifically described to better understand the gist of the invention, and does not limit the present invention unless otherwise specified.

[0012] [Electrostatic Chuck Device] (First Embodiment) FIG. 1 shows a schematic configuration of the electrostatic chuck device of this embodiment and is a cross-sectional view along the height direction of the electrostatic chuck device. FIG. 2 shows a first embodiment of the schematic configuration of the electrostatic chuck device according to the present invention and is an enlarged view of the region α shown in FIG. 1. As shown in FIG. 1, the electrostatic chuck device 1 of this embodiment includes a substrate 10, a laminate 2 including at least a plurality of internal electrodes 20, and a ceramics layer 50 laminated on the upper surface 2a in the thickness direction of the laminate 2. In the electrostatic chuck device 1 of this embodiment, the laminate 2 may include an adhesive layer 30 and an insulating organic film 40 in addition to the internal electrode 20. The adhesive layer 30 is composed of a first adhesive layer 31 and a second adhesive layer 32. The insulating organic film 40 is composed of a first insulating organic film 41 and a second insulating organic film 42.

[0013] In the electrostatic chuck device 1 of this embodiment, on the surface of the substrate 10 (the upper surface in the thickness direction of the substrate 10) 10a, the first adhesive layer 31, the first insulating organic film 41, the internal electrode 20, the second adhesive layer 32, the second insulating organic film 42, and the ceramics layer 50 are laminated in this order.

[0014] In the electrostatic chuck device 1 of the present embodiment, as shown in FIG. 1, the laminate 2 may include at least insulating organic films 40 provided on both surfaces in the thickness direction of the internal electrode 20 (the upper surface 20a in the thickness direction of the internal electrode 20 and the lower surface 20b in the thickness direction of the internal electrode 20). Specifically, a second insulating organic film 42 may be provided on the upper surface 20a side in the thickness direction of the internal electrode 20, and a first insulating organic film 41 may be provided on the lower surface 20b side in the thickness direction of the internal electrode 20.

[0015] A first adhesive layer 31 is provided on the surface of the first insulating organic film 41 opposite to the internal electrode 20 (the lower surface 41b of the first insulating organic film 41). A second adhesive layer 32 is provided between the first insulating organic film 41 and the second insulating organic film 42, between the internal electrode 20 provided on the upper surface 41a in the thickness direction of the first insulating organic film 41.

[0016] In the electrostatic chuck device 1 of the present embodiment, the substrate 10 has a through hole 60 provided so as to penetrate in the thickness direction. Specifically, as shown in FIG. 1, the through hole 60 is provided so as to penetrate the substrate 10 and the laminate 2 in the thickness direction. A sleeve 70 made of an insulating material is inserted into the through hole 60. The sleeve 70 is joined to the inner surface 60a of the through hole 60 via a joining means 80 at the upper part in the thickness direction of the substrate 10. Further, the through hole 60 is a hole for cooling the ceramic layer 50 with gas, a lift pin for lifting up the object to be adsorbed attached to the electrostatic chuck device 1, or an HV pin (DC voltage pin) for applying a voltage to the internal electrode 20.

[0017] As shown in FIG. 1, the ceramic layer 50 preferably has a ceramic base layer 51 and a ceramic surface layer 52 formed on the upper surface (the upper surface in the thickness direction of the ceramic base layer 51) 51a of the ceramic base layer 51 and having irregularities. Further, a through hole 51b penetrating in the thickness direction is provided in the ceramic base layer 51. The inner diameter (diameter perpendicular to the thickness direction) of the through hole 51b is smaller than the inner diameter (diameter perpendicular to the thickness direction) of the through hole 60.

[0018] The internal electrode 20 may be in contact with the first insulating organic film 41 or the second insulating organic film 42. Further, as shown in FIG. 1, the internal electrode 20 may be formed inside the second adhesive layer 32. The arrangement of the internal electrode 20 can be designed as appropriate.

[0019] As shown in FIG. 1, when the plurality of internal electrodes 20 are independent of each other, not only voltages of the same polarity can be applied, but also voltages of different polarities can be applied. The electrode pattern and shape of the internal electrode 20 are not particularly limited as long as it can adsorb an adsorbate such as a conductor, a semiconductor, and an insulator. Further, the internal electrodes 20 do not have to be independent.

[0020] The electrostatic chuck device 1 of the present embodiment is not particularly limited with respect to other layer configurations as long as the ceramic layer 50 is laminated on the upper surface 2a of the laminate 2 including at least the internal electrode 20 laminated on the substrate 10.

[0021] The substrate 10 is not particularly limited, and examples thereof include a ceramic substrate, a silicon carbide substrate, and a metal substrate made of aluminum, stainless steel, or the like.

[0022] The internal electrode 20 is not particularly limited as long as it is made of a conductive material that can exhibit an electrostatic adsorption force when a voltage is applied. As the internal electrode 20, for example, a thin film made of a metal such as copper, aluminum, gold, silver, platinum, chromium, nickel, tungsten, or a thin film made of at least two metals selected from the above metals is preferably used. Such a thin film of a metal includes those formed by vapor deposition, plating, sputtering, or the like, and those formed by applying and drying a conductive paste. Specifically, a metal foil such as a copper foil can be mentioned.

[0023] If the thickness of the second adhesive layer 32 is greater than the thickness of the internal electrode 20, the thickness of the internal electrode 20 is not particularly limited. The thickness of the internal electrode 20 is preferably 20 μm or less. If the thickness of the internal electrode 20 is 20 μm or less, when forming the second insulating organic film 42, unevenness is less likely to occur on its upper surface 42a. As a result, when forming the ceramic layer 50 on the second insulating organic film 42 or when polishing the ceramic layer 50, defects are less likely to occur.

[0024] The thickness of the internal electrode 20 is preferably 1 μm or more. If the thickness of the internal electrode 20 is 1 μm or more, sufficient bonding strength can be obtained when bonding the internal electrode 20 to the first insulating organic film 41 or the second insulating organic film 42.

[0025] When applying voltages with different polarities to each of the plurality of internal electrodes 20, the distance between adjacent internal electrodes 20 (the distance in the direction perpendicular to the thickness direction of the internal electrode 20) is preferably 2 mm or less. If the distance between adjacent internal electrodes 20 is 2 mm or less, sufficient electrostatic force is generated between the adjacent internal electrodes 20, and sufficient adsorption force is generated.

[0026] The distance from the internal electrode 20 to the object to be adsorbed, that is, the distance from the upper surface 20a of the internal electrode 20 to the object to be adsorbed adsorbed on the ceramic surface layer 52 (the total thickness of the second adhesive layer 32, the second insulating organic film 42, the ceramic base layer 51, and the ceramic surface layer 52 present on the upper surface 20a of the internal electrode 20) is preferably 50 μm to 125 μm. If the distance from the internal electrode 20 to the object to be adsorbed is 50 μm or more, the insulation of the laminate composed of the second adhesive layer 32, the second insulating organic film 42, the ceramic base layer 51, and the ceramic surface layer 52 can be ensured. On the other hand, if the distance from the internal electrode 20 to the object to be adsorbed is 125 μm or less, sufficient adsorption force is generated.

[0027] As the adhesive that constitutes the adhesive layer 30, an adhesive mainly composed of one or more resins selected from epoxy resins, phenolic resins, styrene-based block copolymers, polyamide resins, acrylonitrile-butadiene copolymers, polyester resins, polyimide resins, silicone resins, amine compounds, bismaleimide compounds, etc. is used.

[0028] Examples of epoxy resins include bifunctional or polyfunctional epoxy resins such as bisphenol type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, glycidyl ether type epoxy resins, glycidyl ester type epoxy resins, glycidyl amine type epoxy resins, trihydroxyphenylmethane type epoxy resins, tetraglycidylphenolalkane type epoxy resins, naphthalene type epoxy resins, diglycidyl diphenylmethane type epoxy resins, diglycidyl biphenyl type epoxy resins, etc. Among these, bisphenol type epoxy resins are preferred. Among bisphenol type epoxy resins, bisphenol A type epoxy resins are particularly preferred. Also, when an epoxy resin is the main component, if necessary, curing agents and curing accelerators for epoxy resins such as imidazoles, tertiary amines, phenols, dicyandiamides, aromatic diamines, organic peroxides, etc. can be blended.

[0029] Examples of phenolic resins include novolac phenolic resins such as alkylphenol resins, p-phenylphenol resins, bisphenol A type phenolic resins, resol phenolic resins, polyphenyl paraphenol resins, etc.

[0030] Examples of styrene-based block copolymers include styrene-butadiene-styrene block copolymers (SBS), styrene-isoprene-styrene block copolymers (SIS), styrene-ethylene-propylene-styrene copolymers (SEPS), etc.

[0031] The thickness of the adhesive layer 30 (the first adhesive layer 31 and the second adhesive layer 32) is not particularly limited, but is preferably 5 μm to 20 μm, and more preferably 10 μm to 20 μm. If the thickness of the adhesive layer 30 (the first adhesive layer 31 and the second adhesive layer 32) is 5 μm or more, it functions sufficiently as an adhesive. On the other hand, if the thickness of the adhesive layer 30 (the first adhesive layer 31 and the second adhesive layer 32) is 20 μm or less, the inter-electrode insulation of the internal electrode 20 can be ensured without impairing the adsorption force.

[0032] The material constituting the insulating organic film 40 is not particularly limited, and for example, polyesters such as polyethylene terephthalate, polyolefins such as polyethylene, polyimide, polyamide, polyamideimide, polyethersulfone, polyphenylene sulfide, polyether ketone, polyetherimide, triacetyl cellulose, silicone rubber, polytetrafluoroethylene, etc. are used. Among these, polyesters, polyolefins, polyimide, silicone rubber, polyetherimide, polyethersulfone, and polytetrafluoroethylene are preferred because of their excellent insulation properties, and polyimide is more preferred. As the polyimide film, for example, Kapton (trade name) manufactured by Toray DuPont Co., Ltd., Upilex (trade name) manufactured by Ube Industries, Ltd., etc. are used.

[0033] The thickness of the insulating organic film 40 (the first insulating organic film 41 and the second insulating organic film 42) is not particularly limited, but is preferably 10 μm to 100 μm, and more preferably 10 μm to 50 μm. If the thickness of the insulating organic film 40 (the first insulating organic film 41 and the second insulating organic film 42) is 10 μm or more, insulation can be ensured. On the other hand, if the thickness of the insulating organic film 40 (the first insulating organic film 41 and the second insulating organic film 42) is 100 μm or less, sufficient adsorption force is generated. Further, instead of the insulating organic film 40 (the first insulating organic film 41 and the second insulating organic film 42), a ceramic plate made of a ceramic material may be used.

[0034] The through hole 60 penetrates the substrate 10 and the laminate 2 in the thickness direction, but its shape in plan view (the shape seen from the upper surface 51a side of the ceramic base layer 51) is not particularly limited. Examples of the shape of the through hole 60 in plan view include a circular shape and a rectangular shape. The inner diameter of the through hole 60 is not particularly limited, but for example, it is preferably 5 mm to 15 mm, and more preferably 5 mm to 13 mm. The inner diameter of the through hole 60 means the diameter of the through hole 60 when the shape of the through hole 60 in plan view is circular, and means the length of the largest part of the through hole 60 when the shape of the through hole 60 in plan view is other than circular.

[0035] Examples of the insulating material constituting the sleeve 70 include aluminum oxide (alumina), yttria, zirconia, and the like.

[0036] The sleeve 70 is a columnar member, but the cross-sectional shape perpendicular to its longitudinal direction is not particularly limited and is appropriately set according to the shape of the through hole 60 in plan view. The outer diameter of the sleeve 70 is not particularly limited, but for example, it is preferably 4.9 mm to 14.9 mm, and more preferably 4.9 mm to 13 mm. The outer diameter of the sleeve 70 means the diameter of the cross-section perpendicular to the longitudinal direction of the sleeve 70 when the cross-sectional shape perpendicular to the longitudinal direction of the sleeve 70 is circular, and means the length of the largest part of the cross-section perpendicular to the longitudinal direction of the sleeve 70 when the cross-sectional shape perpendicular to the longitudinal direction of the sleeve 70 is other than circular. Further, the sleeve 70 is a columnar member with a hollow inside, and the inner diameter of the sleeve 70 is not particularly limited, but for example, it is preferably 0.5 mm to 5 mm, and more preferably 0.3 mm to 3 mm.

[0037] The distance between the inner surface 60a of the through hole 60 and the sleeve 70 (the gap between the inner surface 60a of the through hole 60 and the sleeve 70) is not particularly limited, but for example, it is preferably 50 μm to 200 μm, and more preferably 50 μm to 100 μm.

[0038] In the electrostatic chuck device 1 of the present embodiment, an adhesive is used as the bonding means 80. The adhesive is not particularly limited, and examples thereof include epoxy resins, polyimide resins, acrylic resins, silane resins, silicone resins, and the like.

[0039] The length of the bonding means 80 made of an adhesive is not particularly limited as long as the sleeve 70 can be fixed to the inner surface 60a of the through hole 60 via the adhesive. For example, it is preferably 5% to 30% of the thickness of the substrate 10, and more preferably 5% to 10% of the thickness of the substrate 10. Also, the installation position of the bonding means 80 is preferably provided within 50% of the thickness of the substrate 10 from the surface 10a of the substrate 10 (the upper surface in the thickness direction of the substrate 10) toward the bottom surface 10b of the substrate 10 (the bottom surface in the thickness direction of the substrate 10). More preferably, it is provided within 30% of the thickness of the substrate 10 from the surface 10a, and particularly preferably, it is provided within 10% of the thickness of the substrate 10 from the surface 10a. Note that the preferred installation positions of the bonding means in the second embodiment, the third embodiment, the fourth embodiment, and the fifth embodiment described below are the same as those of the bonding means 80 described above.

[0040] The material constituting the ceramic layer 50 is not particularly limited, and examples thereof include boron nitride, aluminum nitride, zirconium oxide, silicon oxide, tin oxide, indium oxide, quartz glass, soda glass, lead glass, borosilicate glass, zirconium nitride, titanium oxide, and the like. These materials may be used alone or in combination of two or more. These materials are preferably powders having an average particle diameter of 1 μm to 25 μm. By using such powders, the voids in the ceramic layer 50 can be reduced, and the breakdown voltage of the ceramic layer 50 can be improved.

[0041] The thickness of the ceramic base layer 51 is preferably 10 μm to 80 μm, and more preferably 40 μm to 60 μm. If the thickness of the ceramic base layer 51 is 10 μm or more, sufficient plasma resistance and voltage resistance are exhibited. On the other hand, if the thickness of the ceramic base layer 51 is 80 μm or less, sufficient adsorption force is generated.

[0042] The thickness of the ceramic surface layer 52 is preferably 5 μm to 20 μm. If the thickness of the ceramic surface layer 52 is 5 μm or more, unevenness can be formed over the entire area of the ceramic surface layer 52. On the other hand, if the thickness of the ceramic surface layer 52 is 20 μm or less, sufficient adsorption force is generated.

[0043] The adsorption force of the ceramic surface layer 52 can be improved by polishing its surface, and the unevenness on its surface can be adjusted as the surface roughness Ra. Here, the surface roughness Ra means a value measured by the method defined in JIS B0601 - 1994.

[0044] The surface roughness Ra of the ceramic surface layer 52 is preferably 0.05 μm to 0.5 μm. If the surface roughness Ra of the ceramic surface layer 52 is within the above range, the object to be adsorbed can be adsorbed well. When the surface roughness Ra of the ceramic surface layer 52 increases, the contact area between the object to be adsorbed and the ceramic surface layer 52 decreases, so the adsorption force also decreases.

[0045] In the electrostatic chuck device 1 of the present embodiment, a ceramic layer 50 may be laminated on the upper surface 2a (the upper surface 42a of the second insulating organic film 42) in the thickness direction of the laminate 2 including at least the internal electrode 20 and the insulating organic film 40 via an intermediate layer (not shown).

[0046] The intermediate layer preferably includes at least one of an organic insulating resin and an inorganic insulating resin, and at least one of an inorganic filler and a fibrous filler.

[0047] The organic insulating resin is not particularly limited, and examples thereof include polyimide resins, epoxy resins, acrylic resins, and the like. The inorganic insulating resin is not particularly limited, and examples thereof include silane resins, silicone resins, and the like.

[0048] It is preferable to contain polysilazane in the intermediate layer. Examples of the polysilazane include those known in the art. The polysilazane may be an organic polysilazane or an inorganic polysilazane. These materials may be used alone or in combination of two or more.

[0049] The content of the inorganic filler in the intermediate layer is preferably 100 to 300 parts by mass, more preferably 150 to 250 parts by mass, based on 100 parts by mass of the polysilazane. If the content of the inorganic filler in the intermediate layer is within the above range, inorganic filler particles can form irregularities on the surface of the resin film which is the cured product of the intermediate layer. Therefore, the powder of the sprayed material can easily penetrate between the inorganic filler particles, and the sprayed material can be firmly adhered to the surface of the resin film.

[0050] The inorganic filler is not particularly limited, but is preferably at least one selected from the group consisting of alumina, silica, and yttria. The inorganic filler is preferably at least one of spherical powder and amorphous powder. The spherical powder is a spherical body with rounded corners of the powder particles. The amorphous powder is one with a shape that does not take a regular form, such as crushed, plate-like, scaly, needle-like, etc.

[0051] The average particle diameter of the inorganic filler is preferably 1 μm to 20 μm. When the inorganic filler is spherical powder, its diameter (outer diameter) is taken as the particle diameter. When the inorganic filler is amorphous powder, the longest part of its shape is taken as the particle diameter.

[0052] The fibrous filler is preferably at least one selected from the group consisting of plant fibers, inorganic fibers, and fibrillated organic resins. Examples of the plant fibers include pulp. Examples of the inorganic fibers include fibers made of alumina. Examples of the fibrillated organic resins include fibers made of aramid, Teflon (registered trademark), and the like.

[0053] The inorganic filler is preferably used in combination with the fibrous filler, and the total content of the inorganic filler and the fibrous filler is preferably 10% by volume to 80% by volume with respect to the entire intermediate layer (100% by volume). If the total content of the inorganic filler and the fibrous filler in the intermediate layer is within the above range, the ceramic layer can be uniformly formed on the intermediate layer by thermal spraying.

[0054] The thickness of the intermediate layer is preferably 1 μm to 40 μm, and more preferably 5 μm to 20 μm. If the thickness of the intermediate layer is 1 μm or more, the intermediate layer will not be locally thinned, and the ceramic layer 50 can be uniformly formed on the intermediate layer by thermal spraying. On the other hand, if the thickness of the intermediate layer is 40 μm or less, sufficient adsorption force will be generated.

[0055] In the electrostatic chuck device 1 of the present embodiment described above, the substrate 10 has a through hole 60 provided so as to penetrate in the thickness direction, and a sleeve 70 inserted into the through hole 60 is joined to the through hole 60 via a joining means 80 at the upper part in the thickness direction of the substrate 10. Therefore, when heat generated during the formation of the ceramic layer 50 is transmitted to the electrostatic chuck device 1, the substrate 10 can extend toward the lower side in its thickness direction. Therefore, it is possible to suppress the occurrence of cracks in the ceramic layer 50 (particularly the ceramic base layer 51) due to the thermal expansion of the substrate 10. That is, it is possible to suppress the occurrence of cracks in the ceramic layer 50 (particularly the ceramic base layer 51) due to the difference in thermal expansion between the substrate 10 and the sleeve 70. In particular, when the substrate 10 is made of aluminum and the sleeve 70 is made of ceramics, it is possible to suppress the occurrence of cracks in the ceramic layer 50 (particularly the ceramic base layer 51).

[0056] In the electrostatic chuck device 1 of the present embodiment, since the ceramic layer 50 includes a ceramic base layer 51 and a ceramic surface layer 52 formed on the upper surface 51a of the ceramic base layer 51 and having irregularities, the desired adsorption force can be controlled.

[0057] In the electrostatic chuck device 1 of the present embodiment, since the insulating organic film is a polyimide film, the withstand voltage property is improved.

[0058] (Second Embodiment) FIG. 3 shows a second embodiment of the schematic configuration of the electrostatic chuck device according to the present invention, and is an enlarged view of the region α shown in FIG. 1. In FIG. 3, the same components as those of the electrostatic chuck device of the first embodiment shown in FIG. 2 are denoted by the same reference numerals, and redundant descriptions are omitted.

[0059] The difference between the electrostatic chuck device 100 of the present embodiment and the electrostatic chuck device 1 of the above-described first embodiment is as follows. At the upper part in the thickness direction of the substrate 10, a concave portion 11 having a triangular cross-sectional shape in the thickness direction of the substrate 10 is formed on the inner surface 60a of the through hole 60. The concave portion 11 is filled with a bonding means 80 made of an adhesive, and a sleeve 70 is bonded to the through hole 60 through the bonding means 80.

[0060] Note that the cross-sectional shape of the concave portion 11 is not limited to the above-described triangular shape. Examples of the cross-sectional shape of the concave portion 11 in the thickness direction of the substrate 10 include an arc shape, a rectangular shape, and the like.

[0061] According to the electrostatic chuck device 100 of the present embodiment, it is possible to suppress the occurrence of cracks in the ceramic layer 50 (particularly the ceramic base layer 51) due to the thermal expansion of the substrate 10.

[0062] (Third Embodiment) FIG. 4 shows a third embodiment of the schematic configuration of the electrostatic chuck device according to the present invention, and is an enlarged view of the region α shown in FIG. 1. In FIG. 4, the same components as those of the electrostatic chuck device of the first embodiment shown in FIG. 2 are denoted by the same reference numerals, and redundant descriptions are omitted.

[0063] The difference between the electrostatic chuck device 200 of the present embodiment and the electrostatic chuck device 1 of the above-described first embodiment is as follows. At the upper part in the thickness direction of the substrate 10, a concave portion 12 having an arc-shaped cross-sectional shape in the thickness direction of the substrate 10 is formed on the inner surface 60a of the through hole 60. A convex portion 71 is provided so as to protrude outward from the outer surface 70a of the sleeve 70 in the concave portion 12, and the convex portion 71 having an arc-shaped cross-sectional shape in the longitudinal direction of the sleeve 70 (the thickness direction of the substrate 10) is engaged, and the sleeve 70 is bonded to the through hole 60 through the convex portion 71. That is, in the electrostatic chuck device 200 of the present embodiment, the convex portion 71 is a bonding means for bonding the sleeve 70 to the through hole 60.

[0064] Note that the cross-sectional shape of the concave portion 12 is not limited to the above-described arc shape. Examples of the cross-sectional shape of the concave portion 12 in the thickness direction of the substrate 10 include a triangular shape, a rectangular shape, and the like. Further, the cross-sectional shape of the convex portion 71 is not limited to the above-described arc shape. Examples of the cross-sectional shape of the convex portion 71 in the longitudinal direction of the sleeve 70 include a triangular shape, a rectangular shape, and the like. Also, the cross-sectional shape of the concave portion 12 and the cross-sectional shape of the convex portion 71 do not have to be the same. As long as the convex portion 71 can engage with the concave portion 12, their shapes may be different.

[0065] According to the electrostatic chuck device 200 of the present embodiment, it is possible to suppress the occurrence of cracks in the ceramic layer 50 (particularly the ceramic base layer 51) due to the thermal expansion of the substrate 10.

[0066] (Fourth Embodiment) FIG. 5 shows a fourth embodiment of the schematic configuration of the electrostatic chuck device according to the present invention, and is an enlarged view of the region α shown in FIG. 1. In FIG. 5, the same components as those of the electrostatic chuck device of the first embodiment shown in FIG. 2 are denoted by the same reference numerals, and redundant descriptions are omitted.

[0067] The difference between the electrostatic chuck device 300 of the present embodiment and the electrostatic chuck device 1 of the above-described first embodiment is as follows. An internal thread portion 13 is formed on the inner surface 60a of the through hole 60 at the upper part in the thickness direction of the substrate 10. A male thread portion 72 provided to protrude outward from the outer surface 70a of the sleeve 70 is screwed into the internal thread portion 13, and the sleeve 70 is joined to the through hole 60 via the internal thread portion 13 and the male thread portion 72. That is, in the electrostatic chuck device 300 of the present embodiment, the internal thread portion 13 and the male thread portion 72 are joining means for joining the sleeve 70 to the through hole 60.

[0068] In the electrostatic chuck device 300 of the present embodiment, the case where the female screw portion 13 is formed on the inner surface 60a of the through hole 60 and the male screw portion 72 is formed on the outer surface 70a of the sleeve 70 has been illustrated. However, the electrostatic chuck device of the present invention is not limited to this. In the electrostatic chuck device of the present invention, a male screw portion may be formed on the inner surface of the through hole, and a female screw portion may be formed on the outer surface of the sleeve.

[0069] According to the electrostatic chuck device 300 of the present embodiment, it is possible to suppress the occurrence of cracks in the ceramic layer 50 (particularly the ceramic base layer 51) due to the thermal expansion of the substrate 10.

[0070] (Fifth Embodiment) FIG. 6 shows a fifth embodiment of the schematic configuration of the electrostatic chuck device according to the present invention, and is an enlarged view of the region α shown in FIG. 1. In FIG. 6, the same components as those of the electrostatic chuck device of the first embodiment shown in FIG. 2 are denoted by the same reference numerals, and redundant descriptions are omitted.

[0071] The difference between the electrostatic chuck device 400 of the present embodiment and the electrostatic chuck device 1 of the above-described first embodiment is as follows. A through hole 60 is not formed in the laminate 2 formed in the upper part in the thickness direction of the substrate 10, and the tip of the sleeve 70 is fixed up to the first adhesive layer 31. A through hole 2b that penetrates in the thickness direction of the laminate 2 and has a smaller diameter than the through hole 60 is formed.

[0072] Also, in the electrostatic chuck device 400 of the present embodiment, the sleeve 70 inserted into the through hole 60 is joined to the through hole 60 via the joining means 80 at the upper part in the thickness direction of the substrate 10. Therefore, when heat generated during the formation of the ceramic layer 50 is transmitted to the electrostatic chuck device 400, the substrate 10 can extend toward the lower side in its thickness direction. Therefore, it is possible to suppress the occurrence of cracks in the ceramic layer 50 (particularly the ceramic base layer 51) due to the thermal expansion of the substrate 10.

[0073] Further, in the electrostatic chuck device 400 of the present embodiment, when the through hole 60 is a hole for inserting an HV pin (DC voltage pin) for applying a voltage to the internal electrode, instead of forming a through hole 2b having a smaller diameter than the through hole 60 in the laminate 2, the through hole 60 may be provided in the first adhesive layer 31 and the first insulating organic film 41, and the HV pin may be passed through the inner diameter of the sleeve 70 joined to the inside of the through hole 60 so that the HV pin contacts the internal electrode 20.

[0074] [Method of manufacturing an electrostatic chuck] Referring to FIG. 1, a method of manufacturing the electrostatic chuck device 1 of the present embodiment will be described. A metal such as copper is vapor-deposited on the surface (the upper surface in the thickness direction of the first insulating organic film 41) 41a of the first insulating organic film 41 to form a thin metal film. Then, etching is performed to pattern the thin metal film into a predetermined shape to form the internal electrode 20.

[0075] Next, the second insulating organic film 42 is adhered via the second adhesive layer 32 to the upper surface 20a of the internal electrode 20 to obtain the laminate 2.

[0076] Next, a laser beam is irradiated from above the surface of the laminate 2 to form a hole in the laminate 2 in alignment with the through hole 60 in the substrate 10.

[0077] On the other hand, after forming the through hole 60 in the substrate 10 by a drill or the like, the sleeve 70 is inserted into the through hole 60, and the sleeve 70 is joined to the through hole 60 via the joining means 80.

[0078] Next, the laminate 2 is joined to the surface 10a of the substrate 10 via the first adhesive layer 31 so that the through hole of the laminate 2 and the through hole 60 of the substrate 10 are aligned with the lower surface 41b of the first insulating organic film 41 in the laminate 2 having the hole facing the surface 10a side of the substrate 10.

[0079] Next, a ceramic base layer 51 is formed so as to cover the entire outer surface of the laminate 2. The method for forming the ceramic base layer 51 includes, for example, a method of applying a slurry containing the material constituting the ceramic base layer 51 to the entire outer surface of the laminate 2 and sintering it to form the ceramic base layer 51, a method of spraying the material constituting the ceramic base layer 51 onto the entire outer surface of the laminate 2 to form the ceramic base layer 51, and the like. Here, spraying means a method of forming a film by heating and melting a material to be a film (in this embodiment, the ceramic base layer 51) and then injecting it onto an object to be processed using a compressed gas.

[0080] Next, a ceramic surface layer 52 is formed on the upper surface 51a of the ceramic base layer 51. The method for forming the ceramic surface layer 52 includes, for example, a method of applying masking in a predetermined shape to the upper surface 51a of the ceramic base layer 51 and then spraying the material constituting the ceramic surface layer 52 onto the upper surface 51a of the ceramic base layer 51 to form the ceramic surface layer 52, a method of spraying the material constituting the ceramic surface layer 52 onto the entire upper surface 51a of the ceramic base layer 51 to form the ceramic surface layer 52, and then shaving the ceramic surface layer 52 by a blasting process to form the ceramic surface layer 52 into an uneven shape, and the like.

[0081] Through the above steps, the electrostatic chuck device 1 of this embodiment can be manufactured.

Industrial Applicability

[0082] According to the electrostatic chuck device of the present invention, the substrate has a through-hole provided penetrating in the thickness direction, a sleeve is inserted into the through-hole, and the sleeve is joined to the through-hole via a joining means at the upper part in the thickness direction of the substrate. Therefore, when heat generated during the formation of the ceramic layer is transmitted to the electrostatic chuck device, the substrate can extend toward the lower side in its thickness direction. Accordingly, it is possible to suppress the occurrence of cracks in the ceramic layer due to the thermal expansion of the substrate. That is, it is possible to suppress the occurrence of cracks in the ceramic layer due to the difference in thermal expansion between the substrate and the sleeve.

Explanation of Reference Numerals

[0083] 1,100,200,300,400 Electrostatic chuck device 2 Laminate 10 Substrate 11, 12 Recess 13 Female screw part 20 Internal electrode 30 Adhesive layer 31 First adhesive layer 32 Second adhesive layer 40 Insulating organic film 41 First insulating organic film 42 Second insulating organic film 50 Ceramic layer 51 Ceramic base layer 52 Ceramic surface layer 60 Through hole 70 Sleeve 71 Protrusion 72 Male screw part 80 Joining means

Claims

1. The present invention comprises a substrate, a laminate including at least internal electrodes laminated on the substrate, and a ceramic layer formed by thermal spraying laminated on an upper surface of the laminate in a thickness direction, an electrostatic chuck device, characterized in that the substrate and the laminate have through holes penetrating in a thickness direction, a sleeve made of an insulating material is inserted into a region of the through hole provided in the substrate and a region of the laminate, and the sleeve is joined to the through hole at an upper portion in the thickness direction of the substrate via a joining means that joins a concave portion and a convex portion.

2. The present invention comprises a substrate, a laminate including at least internal electrodes laminated on the substrate, and a ceramic layer formed by thermal spraying laminated on an upper surface of the laminate in a thickness direction, an electrostatic chuck device characterized in that the substrate and the laminate have through holes penetrating in a thickness direction, a sleeve made of an insulating material is inserted into a region of the through hole provided in the substrate and a region of the laminate, and the sleeve is joined to the through hole at an upper portion in the thickness direction of the substrate via a joining means that joins a male thread portion and a female thread portion.

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