JP2000114358A - Electrostatic chuck device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic chuck device of high durability which prevents corrosion from a side surface and dielectric breakdown as well. SOLUTION: For an electrostatic chuck device where at least an electric insulating layer 14, an electrode 18, and chucking layer 22 are laminated on a metal base board 12, an corrosion-preventing insulating material 42 is provided on its side surface. Even if the electrostatic chuck device is subjected to etching process, etc., corrosion from its side surface can be suppressed, thus preventing formation of a corrosion-eroded part, for superior plasma-resistance and etching- resistance, while dielectric breakdown is prevented and high durability is imparted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic chuck device for attracting and fixing a conductor or a semiconductor such as a wafer by electrostatic force.

[0002]

2. Description of the Related Art In a process of processing a semiconductor wafer, a chuck device is used to fix the semiconductor wafer to a predetermined portion of a processing machine. As the chuck device, there are mechanical, vacuum, and electrostatic devices. Among them, the electrostatic chuck device has an advantage that it can adsorb even a non-flat wafer, is easy to handle, and can be used even in a vacuum. An example of a conventional electrostatic chuck device is disclosed in Japanese Patent Publication No. 5-87177. As shown in FIG. 5, the apparatus includes an adhesive layer 2 on a metal base 1.
a, an insulating film 4, an adhesive layer 2b, an electrode 3b made of a thin metal plate, an adhesive layer 2c, and an insulating film 7 are laminated in this order. Is adsorbed. In the metal base 1,
A temperature control means 6 for controlling the temperature through constant temperature water or the like is formed.

FIG. 6 shows an electrostatic chuck device disclosed in Japanese Patent Application Laid-Open No. 8-148549. In this apparatus, a relatively thick insulating adhesive layer 2 is formed on a metal substrate 1, and an insulating film layer having an electrode 3a formed on the lower surface thereof by a metal deposition film or a plating film is bonded thereon. 7
Is adhered, and the semiconductor wafer 5 is adsorbed on the insulating film layer 7.

[0004]

In such an electrostatic chuck device, the electrostatic chuck device shown in FIG. 5 is subjected to dry etching and various reactions repeatedly by plasma in a wafer process. In the electrostatic chuck device shown in FIG. 6, the portions exposed on the side surfaces of the layer 2a, the adhesive layer 2b, and the adhesive layer 2c are particularly plasma-exposed on the side surfaces of the insulating adhesive layer 2. In some cases, erosion is caused by the erosion and the like, and an erosion defect 8 is generated. When such erosion progresses, dielectric breakdown may occur between the electrode and the plasma. SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an electrostatic chuck device that prevents erosion from a side surface, prevents dielectric breakdown, and has high durability.

[0005]

Means for Solving the Problems To achieve the above object, an electrostatic chuck device according to the present invention comprises:
In an electrostatic chuck device in which at least an electric insulating layer, an electrode, and a suction layer are laminated, an erosion preventing insulator is provided on a side surface. It is desirable that the erosion prevention insulator contains a fluorine-based resin or a silicone-based resin. It is desirable that the erosion preventing insulator is in the form of a film. In that case, it is desirable that the adhesive for bonding the erosion preventing insulator also contains a fluorine-based resin or a silicone-based resin. The adsorbing layer is preferably made of a ceramic plate. Further, those having an electrically insulating elastic layer are desirable. The electrically insulating elastic layer is preferably made of an adhesive containing a rubber component and a phenolic antioxidant.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An electrostatic chuck device according to the present invention will be described in detail with reference to FIGS. This electrostatic chuck device 1
Numeral 0 denotes a disk-shaped metal base 12, an electrically insulating elastic layer 14, an insulating film 16, an adhesive layer 20, and an adsorbing layer 22 laminated in this order from the bottom. .. Are formed, and a film-like erosion preventing insulator 42 is adhered to the side surfaces thereof by an adhesive layer 44. The metal base 12 may be a well-known metal base generally used in an electrostatic chuck device. It is desirable that a temperature control means including a heat medium flow path (not shown) through which a heat medium for adjusting the wafer temperature passes is formed inside the metal base 12.

[0007] The electrically insulating elastic layer 14 is excellent in electrical insulation and stress relaxation, and has high adhesion to the metal base 12 and the insulating film 16. Further, those having excellent heat resistance are desirable. In particular, a highly elastic adhesive having a high stress relaxation ability and a low Young's modulus is preferable. In order to satisfy such requirements, a rubber component is added to the adhesive to impart an appropriate elasticity to the adhesive layer, and when the volume of the electrically insulating elastic layer 14 itself and / or the adhesive layer 20 changes, Also relieves stress by this elasticity,
Distortion of the adsorption layer 22 made of a ceramic plate can be prevented. However, those containing a rubber component and a phenolic antioxidant are particularly preferred as those having a high stress relaxation effect.
Particularly preferable as the rubber component is a butadiene-acrylonitrile copolymer, an olefin-based copolymer, a mixture of one or more selected from polyphenylether copolymers, and particularly a butadiene-acrylonitrile copolymer. It is suitable. This is because the butadiene-acrylonitrile copolymer has appropriate elasticity and is excellent in the action of alleviating the stress applied to the adsorption layer 22. The phenolic antioxidant absorbs, for example, radicals generated by the rubber component when exposed to high temperatures, and acts to prevent the rubber component from deteriorating. To prevent As such a phenolic antioxidant, a hindered phenolic antioxidant is particularly preferable. In particular, the phenolic antioxidant has three or more phenol groups in which two or more t-butyl groups are bonded, and has a molecular weight of 700 or more.
More preferably, a compound having a molecular weight of 750 to 1500 is suitable. When this condition is satisfied, even when the electrostatic chuck device is exposed to a high temperature, the rubber component hardly deteriorates, and the effect of relaxing the stress of the adhesive layer can be maintained for a long time.

As a specific adhesive, a butadiene-acrylonitrile copolymer is 10 to 90% by weight (more preferably 50 to 90% by weight, optimally 60 to 80% by weight).
And a compound containing two or more maleimide groups,
10% by weight (more preferably 50 to 10% by weight, optimally 40 to 20% by weight) and 0.3 to 20% by weight of the phenolic antioxidant (more preferably 0.3 to 10% by weight, Mixed at a ratio of 3 to 7% by weight) and a reaction accelerator such as peroxide within 5% by weight (more preferably 0.1 to 2% by weight, and most preferably 0.1 to 1% by weight). Is dissolved in a suitable organic solvent. This is applied, the organic solvent is evaporated, and the organic solvent is semi-cured. Then, the organic solvent is attached to the surface to be adhered and subjected to a heat treatment, whereby a preferable electrically insulating elastic layer 14 can be formed.

The butadiene-acrylonitrile copolymer includes a carboxyl group-containing butadiene-acrylonitrile copolymer having a weight average molecular weight of 1,000 to 200,000 and a carboxyl group equivalent of 30 to 10,000.
Acrylic group-containing butadiene-acrylonitrile copolymer having a weight average molecular weight of 1,000 to 200,000 and an acrylic group equivalent of 500 to 10,000, a weight average molecular weight of 1,000 to 200,000 and an epoxy group equivalent of 500 to
Epoxy-containing butadiene-acrylonitrile copolymer having 10,000, weight average molecular weight of 1,000 to 2
Butadiene-acrylonitrile copolymer having a weight average molecular weight of from 1,000 to 200,000
One or a mixture of two or more selected from piperazinylethylaminocarbonyl group-containing butadiene-acrylonitrile copolymers having 0 and an amino group equivalent of 500 to 10,000 is preferred. The average molecular weight is more preferably from 3000 to 80,000.

The phenolic antioxidant is prepared by thermogravimetric analysis in order to reduce the volume change (mainly shrinkage) of the adhesive layer and the warpage of the adsorption layer 22 due to the stress generated by the difference in the coefficient of thermal expansion. It is preferable that the thermal weight loss rate when heated to 200 ° C. is 5% or less. The thermal weight loss rate is a value measured by raising the temperature of the antioxidant from room temperature to 200 ° C. at a rate of 10 ° C./min.

Specific examples of the phenolic antioxidant include:
1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) -s-triazine-2,4,6- (1
(H, 3H, 5H) trione: molecular weight 784, thermal weight loss rate 0%, 1,1,3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane: molecular weight 545, thermal weight loss rate 2.8%, tetrakis [methylene (3,5-di-t-butyl-4-hydroxyhydrocinnamate)] methane: molecular weight 1178, thermal weight loss 0.2
%, 1,3,5-trimethyl-2,4,6-tris (3,5
-Di-t-butyl-4-hydroxybenzyl) benzene: examples thereof include a molecular weight of 775, a thermal weight loss rate of 0%, and the like. In contrast, for example, 2,6-di-t-butylphenol has a molecular weight of 206.33 and a thermal weight loss rate of 86%.

A filler may be added to the electrically insulating elastic layer 14. As the filler, for example, silica, quartz powder, alumina, calcium carbonate, magnesium oxide, diamond powder, mica, kaolinite, fluororesin powder,
Silicone powder, polyimide powder, zircon powder and the like are used. These fillers may be used alone or in combination of two or more. The content of the filler is within 70% by weight of the total solid, preferably in the range of 5 to 40% by weight. If the content is more than 70% by weight, the viscosity during processing decreases, and the adhesive strength and strength after curing decrease. Although the thickness of the electrically insulating elastic layer 14 is not limited, it is preferably 20 to 200 μm, more preferably 40 to 200 μm, and most preferably 40 to 100 μm.
μm.

The insulating film 16 is preferably an insulating film having a heat-resistant temperature of 150 ° C. or more in consideration of electric characteristics such as a dielectric constant ε, a dielectric loss coefficient tan δ, and a withstand voltage. Examples of the insulating film having a heat resistance of 150 ° C. or more include a fluororesin (fluoroethylene-propylene copolymer or the like), polyethersulfone, polyetherketone, cellulose triacetate, silicone rubber, polyimide, and the like. Particularly, polyimide is preferable. Examples of the polyimide film include “Kapton” (manufactured by Dupont Toray), “Apical” (manufactured by Kanegafuchi Chemical Industry Co., Ltd.), and “Upilex” (manufactured by Ube Industries)
Films sold under such trade names as can be exemplified. The thickness of the insulating film 16 is not limited.
The range of μm is preferable, and 10 to 50 μm is more preferable. Although thinner is preferable from the viewpoint of thermal conductivity, considering mechanical strength, withstand voltage and durability (fatigue resistance),
25-50 μm is particularly preferred.

The electrodes 18 are formed in a predetermined pattern and are made of a conductive material. For example, nickel, chromium, aluminum, and the like are preferably formed by vapor deposition or sputtering, and copper, chromium, and the like are preferably formed by plating, but tin, silver, palladium, and the like and alloys thereof may be used. In particular, silver, platinum, palladium, molybdenum, magnesium, tungsten and their alloys,
Since it can be handled in paste form or powder form, it is excellent in workability and printability. Among them, palladium alloy has good conductivity and workability. Although the thickness of the electrode 18 is not limited, it is preferably 0.1 to 10 μm, more preferably 0.5 to 8 μm. If the thickness is less than 0.1 μm, it is difficult to form a uniform film, and if a highly reactive material such as aluminum is easily oxidized, it is difficult to maintain stable conductivity. On the other hand, when the thickness exceeds 10 μm, the formation cost is increased by the vapor deposition or plating method. The planar shape of the electrode 18 shown in FIG. 2 is an example, and is a circular shape in which an annular non-electrode region 21 is formed around the electrode 18. However, various other modifications are possible.

The adhesive of the adhesive layer 20 may be any one having high adhesiveness and heat resistance, and is preferably the same as the electrically insulating elastic layer 14. From the viewpoint of ensuring high heat resistance, a thermosetting resin is preferable. Although the thickness of the adhesive layer 20 is not limited, it is better to be thin in order to enhance thermal conductivity.
0 μm, more preferably 5 to 50 μm.
μm, more preferably 5 to 30 μm, about 10 μm
m is preferred.

The adsorbing layer 22 is required to be excellent in electric insulation and thermal conductivity and resistant to a solvent, and is preferably made of ceramic. Specifically, alumina, aluminum nitride, silicon nitride, silicon carbide, zirconia, glass and the like are preferable, and those having a smooth surface are used. Among them, alumina ceramic is preferable because of its low cost. Adsorption layer 2
The thickness of No. 2 is not limited, but from the viewpoint of securing sufficient durability while releasing the heat of the adsorption surface 30, 0.1 to 1.0 m.
m is preferably in the range of 0.2 to 0.5 mm, more preferably 0.3 to 0.4 mm.

The erosion-preventing insulator 42 may have any resistance to plasma or the like, but the one made of a fluorine resin or a silicone resin is excellent in heat resistance, chemical resistance and aging resistance. desirable. For example, PTF
Silicone resins (rubbers) such as E, methylphenylvinyl, fluorosilicone and the like are desirable. In particular, methyl phenyl vinyl is preferable because of its excellent radiation resistance. The thickness of the film may be any as long as it can protect the adhesive layer 20 and the like from plasma and the like, and is preferably 10 to 100 μm,
It is more preferably 0 to 75 μm, further preferably 20 to 60 μm, and preferably about 50 μm. The upper end of the erosion preventing insulator has a suction surface 30 as shown in the illustrated example.
It is preferable to keep it lower than that. This is because if the height is set to be equal to or higher than the suction surface 30, the suction function may be affected. The erosion preventing insulator can be formed on the side surface of the electrostatic chuck device by sticking or applying a film-like insulator. The sticking of the film-like erosion preventing insulator is a preferred mode because its manufacturing process is dry and simple.

The adhesive layer 44 only needs to be able to securely fix the erosion preventing insulator 42, and various adhesives and pressure-sensitive adhesives can be applied, but the plasma resistance and the etching resistance are further improved. Therefore, it is desirable that the adhesive layer 44 also contains a fluorine-based resin or a silicone-based resin. The thickness of the adhesive layer 44 is not particularly limited, but is preferably 10 to 50 μm, and more preferably 20 to 40 μm.
μm is more preferred. The illustrated example of the electrostatic chuck device 10
In this case, the film-like erosion preventing insulator 42 is bonded by the adhesive layer 44, but the present invention is not limited to this. For example, a resin having plasma resistance and containing an adhesive component, etc., as long as the film has an adhesive function, without interposing an adhesive layer, may be directly provided on the side surface as a single-layer film. This is a preferred form. For example, a thermosetting resin tape containing a silicone resin or a fluorine resin may be directly adhered to the side surface. Although the thickness of the adhesive tape in such a case is not particularly limited, it is preferably 10 to 50 μm, and more preferably 15 to 50 μm.
45 μm is more preferred.

As shown in FIG. 2, the electrostatic chuck device 10 has three through holes 24 vertically penetrating from the metal substrate 12 to the attraction layer 22. Elevating rods (not shown) are provided in the through holes 24, and the elevating rods project upward from the wafer suction surface, whereby the wafer is elevated. Further, a power supply hole 25 is formed vertically penetrating through the metal base 12, the electrically insulating elastic layer 14, and the insulating film 16, and the power supply hole 25 is formed.
Inside, an energizing means 27 such as a lead wire is connected to the electrode 18 via a connection portion 26 such as soldering, and connected to an external voltage generator via the energizing means 27 to supply a voltage to the electrode 18. . When a voltage is applied to the electrode 18,
Polarized charges are generated on the adsorption surface of the adsorption layer 22, and an object to be adsorbed such as a semiconductor wafer is adsorbed. The inside of the power supply hole 25 is sealed with an insulator 28 such as a resin.

Further, the metal substrate 12, the electrically insulating elastic layer 14, the insulating film 22, the adhesive layer 20, and the adsorption layer 22
May have a plurality of gas passages (not shown) opened to the wafer suction surface. By jetting a small amount of an inert gas, particularly a helium gas excellent in heat conductivity, through these gas passages, cooling of the semiconductor wafer can be promoted. In addition, if necessary, another layer may be further provided. In the electrostatic chuck device according to the present invention, the object to be attracted is not limited to a wafer, but may be any conductor or semiconductor.

This electrostatic chuck device is manufactured, for example, as follows. First, on one side of the insulating film 16,
An electrode 18 having a predetermined pattern is formed. Although a metal film forming an electrode pattern can be formed directly on the insulating film 16, it is easier to form the electrode 18 having a complicated pattern by using a method using a photoresist. . For example, the insulating film 16
A metal film is formed on the entire surface of one side by sputtering, vapor deposition, plating, or the like, and a photoresist layer is formed on the metal film. The photoresist layer may be formed by applying a liquid resist and drying, or may be formed by bonding a photoresist film (dry film) on a metal film by thermocompression bonding.

Subsequently, the photoresist layer is subjected to pattern exposure and development to remove the photoresist at the portion where the metal film is to be dissolved. Then, the exposed portion of the metal film is etched, washed, stripped, and dried. The electrode 18 having a predetermined shape is formed. These operations may be performed using a known method for forming a photoresist pattern. After the electrodes 18 are formed on the insulating film 16, a liquid or film-like adhesive for forming the adhesive layer 20 is coated on the entire surface of the insulating film 16 on which the electrodes 18 are formed so as to cover the electrodes 18. The surface is formed to be flat, dried and semi-cured to form the adhesive layer 20 and the adsorbing layer 22. When the adhesive layer 20 contains a thermosetting adhesive, appropriate heating is performed as necessary to perform a curing process.

On the other hand, a predetermined adhesive is applied to the surface of the insulating film 16 on which the electrodes are not formed to form an electrically insulating elastic layer 14 and adhere to the metal base 12. still,
It is desirable that a power supply hole 25 is formed in the insulating film 16 and the metal substrate 12 in the thickness direction in advance. After the power supply means 27 is connected to the electrode 18, the power supply hole 25 is sealed with an insulator 28. Keep it. The erosion preventing insulator 4 is provided on the side surface via the adhesive layer 44 so as to cover the side end of the adhesive layer 20 which is easily eroded by etching or the like.
2 is provided. Thus, the electrostatic chuck device of the present invention is manufactured. Further, for example, the metal film may be formed by a method of laminating a metal foil (for example, a copper foil) on one surface of the insulating film 16 via an adhesive (for example, a thermosetting adhesive). It is more preferable to use sputtering, vapor deposition, plating, or the like in that a thin layer can be obtained.

According to the electrostatic chuck device of the present invention, since the erosion preventing insulator is provided on the side surface, erosion from the side surface can be suppressed even when the electrostatic chuck device is subjected to an etching process or the like. In addition, the formation of erosion defects is prevented, dielectric breakdown is prevented, and high durability is achieved. In addition, when an adhesive containing a rubber component is used, the rubber component deteriorates due to high temperature, plasma, and the like, and gradually loses elasticity, and the stress relaxation effect decreases, and the wafer suction surface is reduced while wafer processing using plasma or the like is repeated. However, such a problem can be suppressed. The erosion prevention insulator is preferably in the form of a film that can be easily attached. Further, if the adhesive for bonding the film contains a fluorine-based resin or a silicone-based resin, the erosion prevention effect is further enhanced.

In the present invention, the adsorbing layer does not necessarily have to be made of a ceramic as described later, but if the adsorbing layer is made of a ceramic plate as described above,
It is hardly abraded or deformed, is hardly damaged, has good plasma resistance and etching resistance, has extremely high durability, and is excellent in handling properties. In addition, since the adsorbing layer is formed of a ceramic plate, the life of the electrostatic chuck device is prolonged, and the importance of preventing erosion on the side surface is further increased. That is, the electrostatic chuck device provided with the erosion preventing insulator according to the present invention is particularly effective for a device having an adsorption layer made of a ceramic plate. Further, when the electrically insulating elastic layer 14 or the adhesive layer 20 further contains a rubber component, the semi-cured electrically insulating elastic layer 14 and the adhesive layer 20 are subjected to a heat treatment to provide an electrically insulating property. When the elastic layer 14 and the adhesive layer 20 are formed, even if the stress generated due to the difference in the coefficient of thermal expansion or the volume of the adhesive layer slightly changes, the rubber component relieves the stress by elasticity. Can be reduced.

When the electrically insulating elastic layer 14 or the adhesive layer 20 contains a phenolic antioxidant having excellent heat resistance, it absorbs radicals generated from the rubber component, and It is possible to prevent the deterioration of the components over a long period of time. As a result, distortion occurs in the suction layer 22, separation occurs at the bonding interface (particularly, the outer peripheral portion) between the suction layer 22 and the adhesive layer 20, and the cooling performance of the wafer partially decreases, To prevent various problems over a long period of time, such as a deterioration in flatness, a decrease in wafer suction force, and an intense leakage of cooling helium gas supplied slightly between the wafer suction surface and the wafer. The running cost required for component replacement can be reduced. Also,
With the laminated configuration shown in FIG. 1, the thickness can be further reduced as long as the adhesive performance can be ensured, and as a result, bending due to a change in volume due to the adhesive layer 20 is reduced.

Further, the lamination structure is not limited to the illustrated example. For example, as in an electrostatic chuck device 32 shown in FIG. 3, an electrically insulating elastic layer 14 and a polyimide insulating film 16 are formed on a metal base 12. An adhesive layer 40, electrodes 34 and 34 formed by bonding copper foil, an adhesive layer 36, and an alumina ceramic adsorption layer 38 may be sequentially laminated. In addition, for example, as in an electrostatic chuck device 46 shown in FIG.
4. A ceramic insulating plate 48, an adhesive layer 20, and an adsorption layer 50 made of an insulating resin film are formed in this order, and a fixed patterned electrode layer 18 is provided between the adhesive layer 20 and the adsorption layer 50. It may be formed. In the structure shown in FIG. 4, a ceramic insulating plate 48 having excellent insulation properties and having better thermal conductivity than resin is disposed between the metal base 1 and the electrode 18. Electrode 1
The heat transfer from the wafer 5 to the metal substrate 1 can be improved while ensuring a high insulation property between the wafer 8 and the metal base 8.

[0028]

EXAMPLES [Adhesive] Epoxy acrylate ("R-
551 (manufactured by Nippon Kayaku Co., Ltd.) and 1 part by weight of benzoyl peroxide were dissolved in a toluene / methyl ethyl ketone mixture (1: 1) to prepare an adhesive having a solid content of 40% by weight. . [Adhesive] Piperazinylaminocarbonyl group-containing butadiene-acrylonitrile copolymer (molecular weight: 7000)
(0, amino group equivalent: 4000, acrylonitrile content: 25%), 30 parts by weight, 70 parts by weight of a siloxane compound having both ends of maleimide, and 1 part by weight of benzoyl peroxide were mixed and further dissolved in tetrahydrofuran. Thus, a thermosetting adhesive having a solid content of 40% was prepared.

[Adhesive] Peroxide-curable silicone pressure-sensitive adhesive (“YR3286” Toshiba Silicone Co., Ltd.)
[Adhesive] Acrylonitrile-butadiene copolymer having piperazinylethylaminocarbonyl groups at both ends ("Hycar ATBN" Ube Industries, Ltd.) (M = 83.5,
n = 16.5, weight average molecular weight 3600, acrylonitrile content 16.5% by weight)
Dissolved in a mixture of methyl ethyl ketone (1: 1), and in the solution, 20 parts by weight of a maleimide compound represented by the following formula (I), 0.1 part by weight of lauroyl peroxide (“Lauroyl peroxide” manufactured by NOF Corporation), And tetrakis [methylene (3,5-di-t-butyl-4-hydroxy (dihydrocinnamate)] methane ("ADEKA STAB AO-60" manufactured by Asahi Denka Kogyo) as a hindered phenolic antioxidant. Parts by weight were mixed and dissolved in tetrahydrofuran to prepare a liquid adhesive having a solid content of 40% by weight.

[0030]

Embedded image

Example 1 An electrostatic chuck device 10 shown in FIGS. 1 and 2 was manufactured. First, nickel is vapor-deposited on one surface of an insulating film 16 made of a 25 μm-thick polyimide film (“Kapton” manufactured by Du Pont-Toray Co., Ltd.) to a thickness of 500 Å, and then plated with copper to form an electrode layer having a thickness of 2 μm. Was formed. Then, application of a resist, development, etching and cleaning were performed to form an electrode 18.
On the electrode forming surface, the adhesive is dried to a thickness of 1
It was applied to a thickness of 0 μm, dried, heated at 150 ° C. for 5 minutes and semi-cured, and then bonded to an alumina ceramic plate having a smooth surface and a diameter of 4 inches and a thickness of 0.4 mm to form an adsorption layer 22. . At this time, a width of 0.3 m around the electrode 18 is used.
m non-electrode areas 21 were formed. Next, on the other surface (non-electrode formation surface) of the insulating film 16, an adhesive is formed into a film having a thickness of 80 μm and semi-cured, and the film is bonded to an aluminum metal base 12 to form a six-layer laminate. Produced.

Separately, the above-mentioned adhesive is dried to a thickness of 20 μm on one side of a 5 cm-wide tape made of a PTFE film having a thickness of 50 μm (an easily-adhered surface (the surface is roughened to enhance the adhesiveness)). Apply at 150 ° C for 5
Dried for a minute and semi-cured. Then, after attaching the PTFE film tape to the side surface of the above-prepared laminate, it was placed in a hot-air circulating dryer, and was subjected to a step cure at 100 to 150 ° C. to cure the adhesive.
Was manufactured. A power supply hole 25 is formed in the metal substrate 12, the electrically insulating elastic layer 14, and the insulating film 16 in the thickness direction. A voltage could be applied between the substrates 12.

Example 2 An electrostatic chuck device was manufactured in the same manner as in Example 1 except that the PTFE film stuck on the side face was changed to a methylphenylvinyl-based silicone resin film. Example 3 An electrostatic chuck device was manufactured in the same manner as in Example 1 except that the adhesive was changed to the above-mentioned adhesive. [Example 4] Instead of a PTFE film and an adhesive stuck on the side, a commercially available Teflon adhesive tape ("No. 5
491 "(manufactured by Sumitomo 3M Limited, silicone adhesive) was used to manufacture an electrostatic chuck device in the same manner as in Example 1. Example 5 An adhesive was applied on one surface of a release film made of PET that had been subjected to a release treatment so that the thickness after drying was 50 μm, and the adhesive was applied using a hot air circulation type drier.
Drying at 5 ° C. for 5 minutes gave an adhesive tape. This adhesive tape is adhered to the side of the electrostatic chuck device instead of the PTFE film tape in Example 1 above, the peelable film is peeled off, cured, and a single-layer film-like erosion prevention made of only an adhesive is prevented. An electrostatic chuck device on which an insulator was formed was manufactured.

Comparative Example 1 An electrostatic chuck device was manufactured in the same manner as in Example 1 except that the PTFE film tape was not adhered to the side surface.

Test Example 1 (Etching Resistance) Thickness after drying the above adhesive (the solid content rate was adjusted to 50% by weight) on an alumina ceramic plate having a smooth surface of 8 inches in diameter. Is formed to be 100 μm.
It was dried by heating at 0 ° C. for 5 minutes. On that adhesive layer,
5cm x 5cm PTFE film with a thickness of 20
Sample (1) was prepared by bonding via a μm adhesive and heating at 150 ° C. for 2 hours. A sample (2) was produced in the same manner except that the PTFE film was replaced with a methylphenylvinyl-based silicone resin film. Similarly, a sample (3) was prepared in the same manner as in the sample (1) except that the adhesive was changed to the above-mentioned adhesive. Similarly, the commercially available Teflon adhesive tape used in Example 4 was adhered to an alumina ceramic plate to produce a sample (4). Similarly, on the alumina ceramic plate, the adhesive tape used in Example 5 was peeled off and peeled off to form a sample (5) consisting of an adhesive layer having a thickness of 50 μm. For comparison, a portion where the adhesive was exposed was formed on the surface of the ceramic plate.

The five samples thus prepared were placed in a plasma generator (reactive sputter etching system) and subjected to etching for 24 hours. RF output: 2.5 kW, 13.56 MHz Gas pressure: 1 × 10 ⁻¹ Torr Reactive gas: CF ₄ , O ₂ Then, the resin film and the adhesive tape on the alumina ceramic plate were cut together with the adhesive layer, and The cross section was observed. As a result, in sample (5), the average thickness was 50 μm.
m to 30 μm and slightly eroded, but the adhesive layer was not eroded for samples (1) to (4) using a film containing a fluororesin or a silicone resin. The exposed portion of the adhesive is 100
The average thickness of μm was eroded to 65 μm.

Test Example 2 (Dielectric Breakdown Test)
The electrostatic chuck devices of Comparative Example 5 and Comparative Example 1 were placed in a plasma generator (reactive sputter etching method) and subjected to an etching process for 48 hours. RF output: 2.5 kW, 13.56 MHz Gas pressure: 1 × 10 ⁻¹ Torr Reactive gas: CF ₄ , applied voltage of O ₂ electrode: ₂ kV As a result, in Examples 1 to 5, dielectric breakdown did not occur. Was. However, the dielectric breakdown occurred in Comparative Example 1 in 20 hours. In addition, when the side surface of each of the electrostatic chuck devices after the etching process was observed with an electron microscope, in the electrostatic chuck devices of Examples 1 to 5, the film adhered to the side surface remained. In the electrostatic chuck device, the side surface was eroded and became concave.

[0038]

As described above, in the electrostatic chuck device according to the present invention, even when the electrostatic chuck device is subjected to an etching process or the like, erosion from the side thereof can be suppressed, and formation of an erosion defect portion can be prevented. It has excellent plasma resistance and etching resistance, prevents dielectric breakdown, and has high durability. If the erosion prevention insulator is in the form of a film, it can be easily attached, and if the adhesive for bonding the film contains a fluorine-based resin or a silicone-based resin, the erosion prevention is prevented. The effect is further improved.

When the adsorbing layer is made of ceramic, wear and deformation hardly occur, and the durability is extremely high. Therefore, the electrostatic chuck device having such an adsorption layer made of a ceramic plate and provided with an erosion preventing insulator on the side surface has a synergistically long life. In addition, when having an electrically insulating elastic layer, the electrically insulating elastic layer relieves stress caused by a difference in coefficient of thermal expansion or stress caused by a change in the volume of the adhesive due to heat treatment or the like,
The stress applied to the adsorption layer can be reduced, and a decrease in flatness can be suppressed. In addition, by including a phenolic antioxidant with excellent heat resistance in the electrically insulating elastic layer,
It is possible to efficiently absorb radicals generated from the rubber component even at a high temperature, and to prevent oxidative deterioration of the rubber component for a long period of time. As a result, distortion occurs in the adsorbing layer, partial separation occurs at the bonding interface between the adsorbing layer and the adhesive layer, and the cooling property of the object to be adsorbed is reduced, and the flatness of the adsorbing surface is deteriorated, and the adsorbing power It is possible to prevent various problems such as a decrease in the temperature for a long period of time.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a part of an embodiment of an electrostatic chuck device according to the present invention.

FIG. 2 is a plan view of the electrostatic chuck device.

FIG. 3 is a side sectional view showing a layer configuration example of the electrostatic chuck device.

FIG. 4 is a side sectional view showing a layer configuration example of the electrostatic chuck device.

FIG. 5 is a side sectional view of a conventional electrostatic chuck device.

FIG. 6 is a side sectional view of a conventional electrostatic chuck device.

[Explanation of symbols]

 Reference Signs List 5 wafer 10 electrostatic chuck device 12 metal substrate 14 electrically insulating elastic layer 16 insulating film 18 electrode 20 adhesive layer 22 suction layer 30 suction surface 32 electrostatic chuck device 34 electrode 36 adhesive layer 38 suction layer 40 adhesive layer 42 erosion prevention insulator 44 adhesive layer 46 electrostatic chuck device

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shoji Kobayashi 3-1 Yomoe-cho, Shizuoka-shi, Shizuoka Pref.

Claims (7)

[Claims] 1. An electrostatic chuck device in which at least an electric insulating layer, an electrode, and an attraction layer are laminated on a metal base, wherein an erosion preventing insulator is provided on a side surface thereof. apparatus. 2. The electrostatic chuck device according to claim 1, wherein the erosion prevention insulator contains a fluorine resin or a silicone resin. 3. The electrostatic chuck device according to claim 1, wherein the erosion prevention insulator is in the form of a film. 4. The electrostatic chuck device according to claim 3, wherein the erosion prevention insulator is bonded by an adhesive containing a fluorine resin or a silicone resin. 5. The electrostatic chuck device according to claim 1, wherein the suction layer is made of a ceramic plate. 6. The electrostatic chuck device according to claim 1, further comprising an electrically insulating elastic layer. 7. The electrostatic chuck device according to claim 6, wherein the electrically insulating elastic layer is made of an adhesive containing a rubber component and a phenolic antioxidant.