TW202034443A - Electrostatic chuck device - Google Patents

Abstract

An electrostatic chuck device according to the present invention is provided with: a plurality of internal electrodes; an insulative organic film provided on both surface sides of the internal electrode in the thickness direction; and a ceramic layer stacked on an upper surface of a stacked body in the thickness direction with an intermediate layer therebetween, the stacked body including at least the internal electrode and the insulative organic film.

Description

Electrostatic chuck device

The present invention relates to an electrostatic chuck device.

Background technique When manufacturing semiconductor integrated circuits using semiconductor wafers or manufacturing liquid crystal panels using insulating substrates such as glass substrates and films, it is necessary to adsorb and hold substrates such as semiconductor wafers, glass substrates, and insulating substrates at predetermined locations. Therefore, in order to adsorb and hold these substrates, mechanical chucks or vacuum chucks using mechanical methods have been used in the past. However, these holding methods have problems such as difficulty in holding the substrate (adsorbed body) uniformly, inability to use in vacuum, excessive rise in temperature of the sample surface, and the like. Therefore, in recent years, an electrostatic chuck device that can solve the above-mentioned problems is used to hold the adsorbed body.

The main part of the electrostatic chuck device includes: a conductive support member that becomes an internal electrode; and a dielectric layer composed of a dielectric material covering the conductive support member. The main part can adsorb the adsorbed body. If a voltage is applied to the internal electrodes in the electrostatic chuck device to cause a potential difference between the adsorbed body and the conductive support member, an electrostatic attraction force is generated between the dielectric layers. Thereby, the to-be-adsorbed body can be supported by the conductive support member substantially flat.

Regarding the conventional electrostatic chuck device, there is known an electrostatic chuck device in which an insulating organic film is laminated on an internal electrode and a dielectric layer is formed (for example, refer to Patent Document 1). In addition, there is known an electrostatic chuck device in which ceramics are thermally sprayed on internal electrodes to form a dielectric layer (for example, refer to Patent Document 2). There is also known an electrostatic chuck device in which ceramics are thermally sprayed on an insulating organic film laminated on internal electrodes to form a ceramic layer (for example, refer to Patent Document 3). Advanced technical literature Patent literature

[Patent Document 1] JP 2004-235563 A [Patent Document 2] Japanese Kokai Publication No. 6-36583 [Patent Document 3] Japanese Patent No. 5054022

Summary of the invention Problems to be solved by the invention The electrostatic chuck device described in Patent Document 1 uses the Coulomb force formed by a dielectric layer composed of an insulating organic film provided on an internal electrode to adsorb an object to be adsorbed, and has an excellent adsorption force. However, the electrostatic chuck device has the following problems: the resistance under the plasma environment used in the dry etching device is low, and the product life is short.

In addition, the electrostatic chuck device described in Patent Document 2 having a dielectric layer formed by thermal spraying ceramics on internal electrodes has plasma tolerance. However, due to the existence of voids between ceramic particles, it is not only difficult to obtain stable insulation, but also the dielectric layer must be thickened to ensure insulation. Therefore, there is a problem that it is difficult to obtain a high adsorption force with respect to an electrostatic chuck device that uses Coulomb force to adsorb an adherend.

In addition, the electrostatic chuck device described in Patent Document 3 has a ceramic layer formed by thermal spraying ceramics on an insulating organic film laminated on an internal electrode. Since the ceramic layer is thermally sprayed on the insulating organic film, it is necessary to Concavities and convexities are formed on the insulating organic film. However, because of the above-mentioned formation of unevenness or ceramic thermal spraying, the insulating properties of the insulating organic film will be reduced. When used as an electrostatic chuck device, the thickness of the ceramic layer must be at least 100 μm. In addition, when ceramics are thermally sprayed on the insulating organic film, the ends of the insulating organic film cannot be covered with a ceramic layer. If the end of the insulating organic film is exposed, the plasma resistance of the electrostatic chuck device is reduced.

The present invention was completed in view of the above circumstances, and its subject is to provide an electrostatic chuck device which has excellent plasma tolerance and voltage resistance, and also excellent adsorption properties. Means to solve the problem

The present invention has the following aspects. [1] An electrostatic chuck device characterized by comprising: a plurality of internal electrodes; an insulating organic film provided on both sides of the internal electrode in the thickness direction; and a ceramic layer laminated with an intermediate layer in between at least The upper surface in the thickness direction of the laminate of the internal electrode and the insulating organic film. [2] The electrostatic chuck device according to [1], wherein the ceramic layer covers the entire outer surface of the laminate via the intermediate layer. [3] The electrostatic chuck device of [1] or [2], wherein the ceramic layer has: a base layer; and a surface layer, which is formed on the upper surface of the base layer and has unevenness. [4] The electrostatic chuck device according to any one of [1] to [3], wherein the intermediate layer includes: at least one of an organic insulating resin and an inorganic insulating resin; and an inorganic filler and a fibrous filler At least one of the agents. [5] The electrostatic chuck device according to [4], wherein the aforementioned inorganic filler is at least one of spherical powder and amorphous powder. [6] The electrostatic chuck device according to [5], wherein the spherical powder and the amorphous powder system are at least one selected from the group consisting of aluminum oxide, silicon oxide, and yttrium oxide. [7] The electrostatic chuck device according to any one of [4] to [6], wherein the fibrous filler is selected from the group consisting of plant fibers, inorganic fibers, and fiberized organic resins At least one. [8] The electrostatic chuck device according to any one of [1] to [7], wherein the aforementioned insulating organic film is a polyimide film. [9] The electrostatic chuck device according to any one of [1] to [8], wherein the insulating organic film is composed of a first insulating organic film and a second insulating organic film, and the first insulating organic film The film is provided on the lower surface side in the thickness direction of the internal electrode, and the second insulating organic film is provided on the upper surface side in the thickness direction of the internal electrode; between the first insulating organic film and the internal electrode A first adhesive layer is provided on the opposite side; a second adhesive layer is provided between the first insulating organic film and the internal electrode and the second insulating organic film, and the internal electrode is provided on the first 1 The upper surface side in the thickness direction of the insulating organic film; the thickness of the first adhesive layer, the thickness of the first insulating organic film, the thickness of the internal electrode, the thickness of the second adhesive layer, the thickness of the first 2 The total of the thickness of the insulating organic film, the thickness of the intermediate layer, and the thickness of the ceramic layer is 200 μm or less. Invention effect

According to the present invention, an electrostatic chuck device can be provided, which has excellent plasma tolerance and voltage resistance, and also has excellent adsorption properties.

The form used to implement the invention

Hereinafter, the electrostatic chuck device to which the embodiment of the present invention is applied will be described. Furthermore, in the drawings used in the following description, the dimensional ratios of the constituent elements, etc., are not necessarily the same as the actual ones. In addition, this embodiment is specifically described in order to better understand the gist of the invention, and is not intended to limit the invention unless otherwise specified.

[Electrostatic chuck device] FIG. 1 shows the schematic structure of the electrostatic chuck device of this embodiment, which is a cross-sectional view along the height direction of the electrostatic chuck device. As shown in FIG. 1, the electrostatic chuck device 1 of this embodiment includes a substrate 10, a plurality of internal electrodes 20, an adhesive layer 30, an insulating organic film 40, an intermediate layer 50 and a ceramic layer 60. Specifically, as shown in FIG. 1, the electrostatic chuck device 1 of this embodiment includes a substrate 10, a first internal electrode 21, a second internal electrode 22, a first adhesive layer 31, a second adhesive layer 32, and a 1 insulating organic film 41, second insulating organic film 42, intermediate layer 50, and ceramic layer 60.

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, a first adhesive layer 31, a first insulating organic film 41, and a first interior are sequentially laminated The electrode 21 and the second internal electrode 22, the second adhesive layer 32, the second insulating organic film 42, the intermediate layer 50 and the ceramic layer 60.

Insulating organic films 40 are provided on both sides of the internal electrode 20 in the thickness direction (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) sides, respectively. Specifically, the second insulating organic film 42 is provided on the upper surface 21 a side in the thickness direction of the first internal electrode 21 and the upper surface 22 a side in the thickness direction of the second internal electrode 22. In addition, a first insulating organic film 41 is provided on the lower surface 21 b side in the thickness direction of the first internal electrode 21 and the lower surface 22 b side in the thickness direction of the second internal electrode 22.

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). The second adhesive layer 32 is provided between the first insulating organic film 41 and the internal electrode 20 and the second insulating organic film 42. The internal electrode 20 is provided in the thickness direction of the first insulating organic film 41. Upper surface 41a.

The thickness of the first adhesive layer 31, the thickness of the first insulating organic film 41, the thickness of the internal electrode 20, the thickness of the second adhesive layer 32, the thickness of the second insulating organic film 42, the thickness of the intermediate layer 50, and The total thickness of the ceramic layer 60 (ceramic base layer 61, ceramic surface layer 62) (hereinafter referred to as "total thickness (1)") is preferably 200 μm or less, more preferably 170 μm or less. If the aforementioned total thickness (1) is 200 μm or less, the electrostatic chuck device 1 is excellent in withstand voltage characteristics and plasma resistance, and as a result, the adsorption force is excellent.

The total of the thickness of the first adhesive layer 31, the thickness of the first insulating organic film 41, the thickness of the internal electrode 20, the thickness of the second adhesive layer 32, and the thickness of the second insulating organic film 42 (hereinafter referred to as " The total thickness (2)") is preferably 110 μm or less, more preferably 90 μm or less. If the aforementioned total thickness (2) is 110 μm or less, the electrostatic chuck device 1 is excellent in withstand voltage characteristics and plasma resistance, and as a result, the adsorption force is excellent.

The total of the thickness of the second adhesive layer 32 and the thickness of the second insulating organic film 42 (hereinafter referred to as "total thickness (3)") is preferably 50 μm or less, more preferably 40 μm or less. If the aforementioned total thickness (2) is 50 μm or less, the electrostatic chuck device 1 is excellent in withstand voltage characteristics and plasma resistance, and as a result, the adsorption force is excellent.

The ceramic layer 60 is laminated on the upper surface 2 a (the upper surface 42 a 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 with the intermediate layer 50 interposed therebetween.

As shown in Fig. 1, the ceramic layer 60 preferably covers the outer surface of the laminate 2 (the upper surface 2a of the laminate 2 and the side surfaces (the surface of the laminate 2 in the thickness direction, the first adhesive layer 31) via the intermediate layer 50. The side surface of the second adhesive layer 32, the side surface of the first insulating organic film 41, and the side surface of the second insulating organic film 42) 2b over the entire surface. In other words, the intermediate layer 50 preferably covers the outside of the laminated body 2. The entire surface, the ceramic layer 60 preferably covers the entire outer surface of the intermediate layer 50 (the upper surface 50a of the intermediate layer 50, the side surface (the surface of the laminate 2 along the thickness direction) 50b).

As shown in FIG. 1, the ceramic layer 60 preferably has a ceramic base layer 61 and a ceramic surface layer 62 formed on the upper surface of the ceramic base layer 61 (the upper surface in the thickness direction of the ceramic base layer 61) 61a and having unevenness.

The total thickness of the ceramic base layer 61, the thickness of the ceramic surface layer 62, the thickness of the intermediate layer 50, the second adhesive layer 32, and the thickness of the second insulating organic film 42 (hereinafter referred to as "total thickness (4)" is preferably 125 μm or less, preferably 110 μm or less. If the aforementioned total thickness (4) is 125 μm or less, the electrostatic chuck device 1 is excellent in voltage withstand characteristics and plasma resistance, and as a result, the adsorption force is excellent.

The first internal electrode 21 and the second internal electrode 22 may be in contact with the first insulating organic film 41 or the second insulating organic film 42. In addition, the first internal electrode 21 and the second internal electrode 22 may be formed inside the second adhesive layer 32 as shown in FIG. 1. The arrangement of the first internal electrode 21 and the second internal electrode 22 can be appropriately designed.

Since the first internal electrode 21 and the second internal electrode 22 are independent of each other, not only voltages of the same polarity can be applied, but voltages of different polarity can also be applied. The electrode pattern or shape of the first internal electrode 21 and the second internal electrode 22 are not particularly limited as long as they can adsorb adsorbed bodies such as conductors, semiconductors, and insulators. In addition, only the first internal electrode 21 may be provided in the form of a single electrode.

In the electrostatic chuck device 1 of this embodiment, as long as the ceramic layer 60 is laminated on at least the upper surface 42a of the second insulating organic film 42 via the intermediate layer 50, the structure of the other layers is not particularly limited. For example, the substrate 10 shown in FIG. 1 may not be provided.

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

The internal electrode 20 is not particularly limited as long as it is composed of a conductive material that can exhibit electrostatic attraction when a voltage is applied. For the internal electrode 20, for example, the following thin films are suitably used: thin films composed of metals such as copper, aluminum, gold, silver, platinum, chromium, nickel, and tungsten, and thin films composed of at least two metals selected from the foregoing metals. The thin film of the metal mentioned above can be, for example, a film formed by vapor deposition, plating, sputtering, etc., or a film formed by applying a conductive paste and drying it, specifically, metal foil such as copper foil.

As long as 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 the second insulating organic film 42 is formed, it is difficult to produce irregularities on the upper surface 42a thereof. As a result, defects are less likely to occur when the ceramic layer 60 is formed on the second insulating organic film 42 or when the ceramic layer 60 is polished.

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, when the internal electrode 20 and the first insulating organic film 41 or the second insulating organic film 42 are joined, sufficient joining strength can be obtained.

When voltages with different polarities are applied to the first internal electrode 21 and the second internal electrode 22, the distance between the adjacent first internal electrode 21 and the second internal electrode 22 (the distance in the direction perpendicular to the thickness direction of the internal electrode 20) is appropriate It is less than 2mm. If the distance between the first internal electrode 21 and the second internal electrode 22 is 2 mm or less, a sufficient electrostatic force will be generated between the first internal electrode 21 and the second internal electrode 22 to generate a sufficient adsorption force.

The distance from the internal electrode 20 to the adsorbed body, that is, the distance from the upper surface 21a of the first inner electrode 21 and the upper surface 22a of the second inner electrode 22 to the adsorbed body adsorbed on the ceramic surface layer 62 (existing in the first The total thickness of the second adhesive layer 32, the second insulating organic film 42, the intermediate layer 50, the ceramic base layer 61 and the ceramic surface layer 62 on the upper surface 21a of the internal electrode 21 and the upper surface 22a of the second internal electrode 22 ) Should be 50μm~125μm. If the distance from the internal electrode 20 to the body to be adsorbed is 50 μm or more, it is possible to ensure that the second adhesive layer 32, the second insulating organic film 42, the intermediate layer 50, the ceramic base layer 61 and the ceramic surface layer 62 constitute a laminate body Insulation. On the other hand, if the distance from the internal electrode 20 to the adsorbed body is 125 μm or less, sufficient adsorption force will be generated.

Regarding the adhesive constituting the adhesive layer 30, used is selected from epoxy resin, phenol resin, styrene block copolymer, polyamide resin, acrylonitrile-butadiene copolymer, polyester resin, polyamide One or two or more resins such as amine resin, silicone resin, amine compound, bismaleimide compound, etc. are used as the main component of the adhesive.

Regarding epoxy resins, bisphenol type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, glycidyl ether type epoxy resins, glycidyl ester type epoxy resins, Glycidylamine type epoxy resin, trihydroxyphenylmethane type epoxy resin, tetraglycidylphenol alkane type epoxy resin, naphthalene type epoxy resin, diglycidyl diphenylmethane type epoxy resin Resins, diglycidyl biphenyl epoxy resins and other bifunctional or polyfunctional epoxy resins. Among these, bisphenol type epoxy resin is preferable. Among bisphenol epoxy resins, bisphenol A epoxy resins are particularly preferred. In addition, when epoxy resin is used as the main component, curing agents for epoxy resins such as imidazoles, third amines, phenols, dicyandiamines, aromatic diamines, organic peroxides, etc. Hardening accelerator.

Examples of phenol resins include phenol resins such as alkylphenol resins, p-phenylphenol resins, and bisphenol A phenol resins, resol resins, and polyphenyl p-phenol resins.

Regarding the styrene-based block copolymer, styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene- Ethylene-propylene-styrene copolymer (SEPS), etc.

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 can fully function 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, it is possible to ensure the insulation between the electrodes of the internal electrodes 20 without damaging the adsorption force.

The material constituting the insulating organic film 40 is not particularly limited. For example, polyesters such as polyethylene terephthalate, polyolefins such as polyethylene, polyimide, polyamide, and polyamide are used. Imidine, polyether sulfide, polyphenylene sulfide, polyether ketone, polyetherimide, cellulose triacetate, silicone rubber, polytetrafluoroethylene, etc. Among these, polyesters, polyolefins, polyimides, silicone rubbers, polyetherimides, polyether turbinates, and polytetrafluoroethylene are preferred in terms of excellent insulation properties, and more preferred For polyimide. Regarding the polyimide film, for example, Kapton (trade name) manufactured by Toray DuPont Co., Ltd., UPILEX (trade name) manufactured by Ube Industries, Ltd., and the like are used.

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 can be generated.

The intermediate layer 50 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.

The organic insulating resin is not particularly limited, and examples thereof include polyimide resins, epoxy resins, and acrylic resins. The inorganic insulating resin is not particularly limited, and examples thereof include silane-based resins and silicone-based resins.

The intermediate layer 50 preferably contains polysilazane. The polysilazane can be exemplified by those well known in the field. The polysilazane can be an organic polysilazane or an inorganic polysilazane. These materials can be used alone or in combination of two or more.

The content of the inorganic filler in the intermediate layer 50 is preferably 100 parts by mass to 300 parts by mass, preferably 150 parts by mass to 250 parts by mass relative to 100 parts by mass of polysilazane. If the content of the inorganic filler in the intermediate layer 50 is within the aforementioned range, since the inorganic filler particles can form irregularities on the surface of the resin film that is the hardened material of the intermediate layer 50, the powder of the thermal spray material is likely to bite into the inorganic filler particles In the meantime, the thermal spray material can be firmly adhered to the surface of the aforementioned resin film.

The inorganic filler is not particularly limited, and it is preferably at least one selected from the group consisting of aluminum oxide, silicon oxide, and yttrium oxide. The inorganic filler is at least one of spherical powder and amorphous powder. Furthermore, the so-called spherical powder is a spherical body with rounded corners of powder particles. In addition, the so-called amorphous powder is a shape that does not take a fixed shape, such as a broken shape, a plate shape, a scale shape, and a needle shape.

The average particle size of the inorganic filler is preferably 1μm~20μm. When the inorganic filler is a spherical powder, the diameter (outer diameter) is defined as the particle diameter, and when the inorganic filler is an amorphous powder, the longest position of the shape is defined as the particle diameter.

The fibrous filler is preferably selected from at least one of the group consisting of plant fibers, inorganic fibers and fibrillated organic resins. Regarding plant fibers, wood pulp can be mentioned. Regarding the inorganic fiber, a fiber composed of alumina, etc. may be mentioned. Regarding the fiberized organic resin, fibers composed of aromatic polyamide or Teflon (registered trademark) can be cited.

The inorganic filler is preferably used together with the fibrous filler, and the total content of the inorganic filler and the fibrous filler is preferably 10% to 80% by volume relative to the entire intermediate layer 50 (100% by volume). If the total content of the inorganic filler and fibrous filler in the intermediate layer 50 is within the above range, the ceramic layer 60 can be uniformly formed on the intermediate layer 50 by thermal spraying.

The thickness of the intermediate layer 50 is preferably 1 μm to 40 μm, preferably 5 μm to 20 μm. If the thickness of the intermediate layer 50 is 1 μm or more, the ceramic layer 60 can be uniformly formed on the intermediate layer 50 by thermal spraying without locally making the intermediate layer 50 thinner. On the other hand, if the thickness of the intermediate layer 50 is 40 μm or less, sufficient adsorption force will be generated.

The material constituting the ceramic layer 60 is not particularly limited. For example, boron nitride, aluminum nitride, zirconium oxide, silicon oxide, tin oxide, indium oxide, quartz glass, soda lime glass, lead glass, borosilicate glass, Zirconium nitride, titanium oxide, etc. These materials can be used alone or in combination of two or more. These materials should preferably be powders with an average particle size of 1μm~25μm. By using the above powder, the voids of the ceramic layer 60 can be reduced and the withstand voltage of the ceramic layer 60 can be improved.

The thickness of the ceramic base layer 61 is preferably 10 μm to 80 μm, preferably 40 μm to 60 μm. If the thickness of the ceramic base layer 61 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 61 is 80 μm or less, sufficient adsorption force will be generated.

The thickness of the ceramic surface layer 62 is preferably 5 μm to 20 μm. If the thickness of the ceramic surface layer 62 is 5 μm or more, unevenness can be formed over the entire area of the ceramic surface layer 62. On the other hand, if the thickness of the ceramic surface layer 62 is 20 μm or less, sufficient adsorption force will be generated.

The surface of the ceramic surface layer 62 can be polished to increase its adsorption force, and the unevenness of the surface can be adjusted in the form of surface roughness Ra. Here, the so-called surface roughness Ra means the value measured by the method defined in JIS B0601-1994.

The surface roughness Ra of the ceramic surface layer 62 is preferably 0.05 μm to 0.5 μm. If the surface roughness Ra of the ceramic surface layer 62 is within the aforementioned range, the adsorbed body can be adsorbed well. If the surface roughness Ra of the ceramic surface layer 62 becomes larger, since the contact area between the adsorbed body and the ceramic surface layer 62 becomes smaller, the adsorption force also becomes smaller.

In the electrostatic chuck device 1 of the present embodiment described above, it is provided with: a plurality of internal electrodes 20; an insulating organic film 40 provided on both sides in the thickness direction of the internal electrode 20; and a ceramic layer 60 separating it The intermediate layer 50 is laminated on the upper surface 2 a in the thickness direction of the laminated body 2 including at least the internal electrode 20 and the insulating organic film 40. Therefore, at least on the upper surface 2a side in the thickness direction of the laminated body 2, the plasma resistance and voltage resistance can be improved, and abnormal discharge during use can be suppressed. Therefore, the electrostatic chuck device 1 of this embodiment is also excellent in adsorbability.

In the electrostatic chuck device 1 of this embodiment, if the ceramic layer 60 covers the entire outer surface of the laminated body 2 with the intermediate layer 50 interposed, it can be made resistant to plasma on the upper surface 2a side and the side surface 2b side of the laminated body 2. Improved performance and withstand voltage, which can suppress abnormal discharge during use. Therefore, the electrostatic chuck device 1 of this embodiment is more excellent in adsorption.

In the electrostatic chuck device 1 of this embodiment, the ceramic layer 60 has a ceramic base layer 61 and a ceramic surface layer 62 formed on the upper surface 61a of the ceramic base layer 61 and having unevenness, so that the desired adsorption force can be controlled.

In the electrostatic chuck device 1 of the present embodiment, the intermediate layer 50 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. The ceramic layer 60 is uniformly formed on the intermediate layer 50.

In the electrostatic chuck device 1 of this embodiment, by the inorganic filler being at least one of spherical powder and amorphous powder, the filling state of the resin in the intermediate layer 50 can be uniformly dispersed or densely filled. In this way, the blending design is performed, and a part of the filler is exposed from the resin, so that the adhesion to the ceramic base layer 61 can be improved.

In the electrostatic chuck device 1 of this embodiment, the fibrous filler is at least one selected from the group consisting of plant fibers, inorganic fibers, and fiberized organic resins, so that the intermediate layer 50 The strength and toughness are improved, and the adhesion with the ceramic base layer 61 can be improved by arranging fibers on the surface of the intermediate layer 50, and the difference in thermal expansion coefficient between the ceramic base layer 61 and the insulating organic film 40 between the intermediate layer 50 The resulting deformation.

In the electrostatic chuck device 1 of this embodiment, since the insulating organic film is a polyimide film, the withstand voltage is improved.

In the electrostatic chuck device 1 of this embodiment, the inorganic filler composed of spherical powder and amorphous powder is at least one selected from the group consisting of alumina, silica, and yttrium oxide , To improve plasma resistance and voltage resistance.

[Manufacturing method of electrostatic chuck] 1, the method of manufacturing the electrostatic chuck device 1 of this embodiment will be described. A metal such as copper is vapor-deposited on the surface of the first insulating organic film 41 (the upper surface in the thickness direction of the first insulating organic film 41) 41a to form a thin metal film. Then, etching is performed to pattern the thin metal film into a specific shape to form the first internal electrode 21 and the second internal electrode 22.

Next, the second insulating organic film 42 is adhered to the upper surface 20 a of the internal electrode 20 via the second adhesive layer 32.

Then, so that the lower surface 41b of the first insulating organic film 41 becomes the surface 10a side of the substrate 10, the first insulating organic film 41, the internal electrode 20, the second adhesive layer 32, and the second insulating organic film The layered body composed of 42 is bonded to the surface 10 a of the substrate 10 via the first adhesive layer 31.

Next, the intermediate layer 50 is formed so as to cover the entire outer surface of the laminate 2 containing the internal electrode 20 and the insulating organic film 40. The method of forming the intermediate layer 50 is not particularly limited as long as the intermediate layer 50 can be formed so as to cover the entire outer surface of the laminate 2. As for the method of forming the intermediate layer 50, for example, a bar coating method, a spin coating method, a thermal spray method, etc.

Then, the ceramic base layer 61 is formed so as to cover the entire outer surface of the intermediate layer 50. The method of forming the ceramic base layer 61 can be exemplified: a method of coating a slurry containing the material constituting the ceramic base layer 61 on the entire outer surface of the intermediate layer 50 and sintering to form the ceramic base layer 61. The material of the layer 61 is thermally sprayed on the entire outer surface of the intermediate layer 50 to form the ceramic base layer 61. Here, the so-called thermal spraying refers to a method of forming a film by heating and melting the material that becomes the coating (ceramic base layer 61 in this embodiment), and then ejecting compressed gas toward the object to be processed.

Next, a ceramic surface layer 62 is formed on the upper surface 61 a of the ceramic base layer 61. The method of forming the ceramic surface layer 62 can be exemplified: after the upper surface 61a of the ceramic base layer 61 is masked in a specific shape, the material constituting the ceramic surface layer 62 is thermally sprayed on the upper surface 61a of the ceramic base layer 61 to form the ceramic surface layer 62 The method is to thermally spray the material constituting the ceramic surface layer 62 on the entire upper surface 61a of the ceramic base layer 61 to form the ceramic surface layer 62, and then use sandblasting to cut the ceramic surface layer 62 to form the ceramic surface layer 62 into an uneven shape. Methods etc.

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

Hereinafter, the present invention will be explained in more detail using examples and comparative examples, but the present invention is not limited to the following examples.

[Example 1] As the first insulating organic film 41, a polyimide film with a thickness of 12.5 μm (trade name: Kapton, manufactured by Toray DuPont) was plated with copper in a thickness of 9 μm on one side. After applying a photoresist to the surface of the copper foil, a development process is performed after pattern exposure, and unnecessary copper foil is removed by etching. Then, the copper foil on the polyimide film is washed to remove the photoresist, and the first internal electrode 21 and the second internal electrode 22 are formed. On the first internal electrode 21 and the second internal electrode 22, an insulating adhesive sheet semi-cured by drying and heating is laminated as the second adhesive layer 32. Regarding the insulating adhesive sheet, 27 parts by mass of bismaleimide resin, 3 parts by mass of diaminosiloxane, 20 parts by mass of resol resin, 10 parts by mass of biphenyl epoxy resin, and 240 parts by mass of ethyl acrylate-butyl acrylate-acrylonitrile copolymer was mixed and dissolved in an appropriate amount of tetrahydrofuran and then formed into a sheet. Then, a polyimide film (trade name: Kapton, manufactured by Toray DuPont Co., Ltd.) with a thickness of 12.5 μm as the second insulating organic film 42 was pasted to obtain a laminated body bonded by heat treatment. In addition, the thickness of the second adhesive layer 32 after drying was 20 μm.

Furthermore, the first insulating organic film 41 in the above-mentioned laminate is on the opposite side to the surface on which the first internal electrode 21 and the second internal electrode 22 are formed, and the laminated body is composed of the semi-cured insulating adhesive sheet A sheet composed of an insulating adhesive agent of the same composition serves as the first adhesive agent layer 31. Then, the laminated body is stuck to the aluminum substrate 10, and the bonding is performed by heat treatment. Furthermore, the thickness of the first adhesive layer 31 after drying was 10 μm.

Then, 100 parts by mass of polysilazane and 200 parts by mass of an inorganic filler composed of alumina (average particle size: 3μm) are mixed with butyl acetate as a dilution medium, and then the inorganic filler is made uniform by an ultrasonic dispersion machine Disperse to make paint.

Next, the coating is sprayed on the surface of the second insulating organic film 42 of the laminate of the substrate 10 and the side surface of the laminate 2, and then heated and dried to form the intermediate layer 50. In addition, the thickness of the intermediate layer 50 after drying on the surface of the second insulating organic film 42 is 10 μm.

Next, aluminum oxide (Al ₂ O ₃ ) powder (average particle size: 8 μm) is thermally sprayed on the entire surface of the intermediate layer 50 by a plasma thermal spray method to form a ceramic base layer 61 with a thickness of 50 μm.

Then, after masking the surface of the ceramic base layer 61 with a specific shape, the above alumina (Al ₂ O ₃ ) powder (average particle size: 8 μm) is thermally sprayed on the surface of the ceramic base layer 61 to form a ceramic surface layer with a thickness of 15 μm 62.

Then, the adsorption surface of the ceramic surface layer 62 of the adsorbed object was ground with a diamond grinding stone to obtain the electrostatic chuck device of Example 1. The surface of the obtained electrostatic chuck device was measured by JIS B0601-1994, and as a result, the surface roughness Ra was 0.3 μm.

[Example 2] Except that the thickness of the first insulating organic film 41 and the thickness of the second insulating organic film 42 in the aforementioned Example 1 were changed to 25 μm, the electrostatic chuck device of Example 2 was obtained in the same manner as in Example 1.

[Example 3] In addition to changing the thickness of the first insulating organic film 41 and the thickness of the second insulating organic film 42 to 38μm, the thickness of the second adhesive layer 32 to 10μm, the thickness of the first internal electrode 21 and The electrostatic chuck device of Example 3 was obtained by the same method as Example 1 except that the thickness of the second internal electrode 22 was changed to 5 μm.

[Comparative Example 1] In addition to changing the thickness of the first insulating organic film 41 and the thickness of the second insulating organic film 42 to 50 μm, the thickness of the ceramic base layer 61 to 30 μm, the thickness of the intermediate layer 50 to 15 μm, and the 1 The thickness of the internal electrode 21 and the thickness of the second internal electrode 22 were changed to 5 μm, and the thickness of the first adhesive layer 31 was changed to 20 μm. The electrostatic chuck device of Comparative Example 1 was obtained in the same manner as in Example 1.

[Comparative Example 2] The electrostatic chuck device of Comparative Example 2 was obtained in the same manner as in Comparative Example 1, except that the thickness of the ceramic base layer 61 in Comparative Example 1 was changed to 50 μm.

[Comparative Example 3] The electrostatic clamp of Comparative Example 3 was obtained by the same method as Comparative Example 2 except that the thickness of the ceramic surface layer 62 in the aforementioned Comparative Example 2 was changed to 20 μm, the thickness of the ceramic base layer 61 was changed to 80 μm, and the thickness of the intermediate layer 50 was changed to 30 μm.头装置。 Head device.

[Comparative Example 4] Except that the intermediate layer 50 was not provided in the aforementioned Comparative Example 3, the surface of the second insulating organic film 42 was thermally sprayed with alumina (Al ₂ O ₃ ) powder (average particle size: Except 8 μm), the electrostatic chuck device of Comparative Example 4 was obtained by the same method as Comparative Example 3.

Table 1 shows the thickness of each layer in the electrostatic chuck device obtained in Example 1 to Example 3 and Comparative Example 1 to Comparative Example 4 and the total value thereof.

[Table 1]

Next, the electrostatic chuck devices obtained in the foregoing Examples 1 to 3 and Comparative Examples 1 to 4 were used to evaluate the withstand voltage characteristics, the adsorption force, and the plasma resistance. The results are shown in Table 2.

[Evaluation item] >Withstand voltage characteristics> The withstand voltage characteristics were evaluated by applying a voltage of ±2.5 kV to the first internal electrode 21 and the second internal electrode 22 from a high voltage power supply device under a vacuum (10 Pa) in an electrostatic chuck device, and maintaining the voltage for 2 minutes. Observe visually for 2 minutes, and set the ones with no change as "pass", and set the ones with insulation failure between the electrodes or the insulating organic film and ceramic layer as "unqualified".

>Adsorption power> The adsorption force is to use the silicon dummy wafer as the adsorbed body to be adsorbed on the surface of the electrostatic chuck device under vacuum (below 10Pa), and a voltage of ±2.5kV is applied to the first internal electrode 21 and the second internal electrode 22 After that, hold for 30 seconds. While maintaining the applied voltage, helium gas was introduced from the through hole provided in the substrate 10 to increase the gas pressure while measuring the leakage amount of the helium gas. When the gas pressure is 100 Torr, the dummy wafer can be adsorbed stably as "Pass", and the unit cannot be stably adsorbed as "Fail". The so-called stable adsorption refers to a state where the phenomenon of wafer floating due to the increase of helium pressure and the rapid increase of helium leakage does not occur.

>Plasma resistance> Plasma resistance is achieved by installing an electrostatic chuck device on a parallel plate type RIE device, and introducing oxygen (10sccm) and carbon tetrafluoride gas (40sccm) under vacuum (below 20Pa) and high-frequency power supply (output 250W) for visual observation Changes in the surface state of the electrostatic chuck device after 24 hours of exposure. The ceramic layer remaining on the entire surface is set as "pass", and the part where the ceramic layer disappears and the insulating organic film is exposed is set as "unqualified".

[Table 2] Example 1 Example 2 Example 3 Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Withstand voltage characteristics qualified qualified qualified qualified qualified qualified qualified Adsorption qualified qualified qualified qualified Unqualified Unqualified Unqualified Plasma resistance qualified qualified qualified Unqualified qualified qualified Unqualified

It can be seen from Table 2 that although the electrostatic chuck device obtained in Examples 1 to 3 is a thin film whose distance from the surface 10a of the substrate 10 to the surface of the ceramic surface layer 62 is less than 200μm, the voltage resistance characteristics and plasma resistance are confirmed Excellent, as a result, the adsorption force is excellent.

On the other hand, in the electrostatic chuck device obtained in Comparative Example 1, since the ceramic base layer 61 is thin, sufficient plasma resistance cannot be obtained. In the electrostatic chuck devices obtained in Comparative Example 2 and Comparative Example 3, it was confirmed that since the distance from the surface 10a of the substrate 10 to the surface of the ceramic surface layer 62 exceeds 200 μm, the adsorption force is poor. Furthermore, in the electrostatic chuck device obtained in Comparative Example 4, it was confirmed that the ceramic thermal spraying material could not be sufficiently adhered to the surface of the second insulating organic film 42 because it did not have the intermediate layer 50, and the plasma resistance was poor. Industrial availability

According to the electrostatic chuck device of the present invention, the ceramic layer is laminated on the upper surface in the thickness direction of the laminate including the internal electrode and the insulating organic film provided on both sides in the thickness direction of the internal electrode. Can have excellent plasma resistance and withstand voltage characteristics, and obtain high adsorption force. Therefore, according to the electrostatic chuck device of the present invention, conductive bodies such as wafers or semiconductors for dry etching devices in the semiconductor manufacturing process can be stably electrostatically attracted and held.

1: Electrostatic chuck device 2: Layered body 2a: upper surface 2b: side 10: substrate 10a: surface 20: Internal electrode 20a: upper surface 20b: lower surface 21: 1st internal electrode 21a: upper surface 21b: lower surface 22: 2nd internal electrode 22a: upper surface 22b: lower surface 30: Adhesive layer 31: The first adhesive layer 32: The second adhesive layer 40: insulating organic film 41: The first insulating organic film 41a: upper surface 41b: lower surface 42: The second insulating organic film 42a: upper surface 50: middle layer 50a: upper surface 50b: side 60: ceramic layer 61: Ceramic base layer 61a: upper surface 62: ceramic surface

FIG. 1 shows the schematic structure of the electrostatic chuck device of the present invention, which is a cross-sectional view along the height direction of the electrostatic chuck device.

1: Electrostatic chuck device

2: Layered body

2a: upper surface

2b: side

10: substrate

10a: surface

20: Internal electrode

20a: upper surface

20b: lower surface

21: 1st internal electrode

21a: upper surface

21b: lower surface

22: 2nd internal electrode

22a: upper surface

22b: lower surface

30: Adhesive layer

31: The first adhesive layer

32: The second adhesive layer

40: insulating organic film

41: The first insulating organic film

41a: upper surface

41b: lower surface

42: The second insulating organic film

42a: upper surface

50: middle layer

50a: upper surface

50b: side

60: ceramic layer

61: Ceramic base layer

61a: upper surface

62: ceramic surface

Claims (9)

An electrostatic chuck device, characterized by having: Multiple internal electrodes; Insulating organic film, which is provided on both sides of the internal electrode in the thickness direction; and A ceramic layer is laminated on the upper surface in the thickness direction of a laminate including at least the internal electrode and the insulating organic film via an intermediate layer. The electrostatic chuck device of claim 1, wherein the ceramic layer covers the entire outer surface of the laminated body via the intermediate layer. Such as the electrostatic chuck device of claim 1 or 2, wherein the aforementioned ceramic layer has: Basal layer; and The surface layer is formed on the upper surface of the base layer and has unevenness. The electrostatic chuck device of any one of claims 1 to 3, wherein the aforementioned intermediate layer comprises: At least one of organic insulating resin and inorganic insulating resin; and At least one of inorganic filler and fibrous filler. The electrostatic chuck device of claim 4, wherein the aforementioned inorganic filler is at least one of spherical powder and amorphous powder. The electrostatic chuck device of claim 5, wherein the spherical powder and the amorphous powder system are at least one selected from the group consisting of aluminum oxide, silicon oxide, and yttrium oxide. The electrostatic chuck device according to any one of claims 4 to 6, wherein the fibrous filler is at least one selected from the group consisting of plant fibers, inorganic fibers, and fiberized organic resins. The electrostatic chuck device according to any one of claims 1 to 7, wherein the aforementioned insulating organic film is a polyimide film. An electrostatic chuck device according to any one of claims 1 to 8, wherein the insulating organic film is composed of a first insulating organic film and a second insulating organic film, and the first insulating organic film is provided in the interior On the lower surface side in the thickness direction of the electrode, the second insulating organic film is provided on the upper surface side in the thickness direction of the internal electrode; A first adhesive layer is provided on the surface of the first insulating organic film on the opposite side to the internal electrode; A second adhesive layer is provided between the first insulating organic film and the internal electrode and the second insulating organic film, and the internal electrode is provided on the upper surface of the first insulating organic film in the thickness direction side; The thickness of the first adhesive layer, the thickness of the first insulating organic film, the thickness of the internal electrode, the thickness of the second adhesive layer, the thickness of the second insulating organic film, the thickness of the intermediate layer, and The total thickness of the aforementioned ceramic layers is 200 μm or less.

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