JP7415732B2 - electrostatic chuck device - Google Patents

Description

The present invention relates to an electrostatic chuck device.

Conventionally, in the semiconductor manufacturing process of manufacturing semiconductor devices such as IC, LSI, VLSI, etc., a plate-shaped sample such as a silicon wafer is fixed by electrostatic adsorption to an electrostatic chuck member equipped with an electrostatic chuck function and held at a predetermined position. Processing is performed.
For example, when etching or the like is performed on this plate-shaped sample in a plasma atmosphere, the surface of the plate-shaped sample becomes hot due to the heat of the plasma, causing problems such as the resist film on the surface bursting.
Therefore, an electrostatic chuck device is used to maintain the temperature of this plate-shaped sample at a desired constant temperature. The electrostatic chuck device includes a temperature control base member in which a flow path for circulating a cooling medium for temperature control is formed inside the metal member on the bottom surface of the electrostatic chuck member, and a silicone-based adhesive is attached to the bottom surface of the electrostatic chuck member. This is a device that is joined and integrated through the
In this electrostatic chuck device, heat exchange is performed by circulating a cooling medium for temperature adjustment in the flow path of the temperature adjustment base member, and the temperature of the plate-shaped sample fixed on the top surface of the electrostatic chuck member is maintained at a desired constant level. Electrostatic adsorption is performed while maintaining the temperature, and various plasma treatments are applied to this plate-shaped sample.

By the way, in an electrostatic chuck device, in order to prevent discharge between the temperature adjustment base member, which becomes an electrode, and the wafer, which occurs during plasma processing, a temperature adjustment base member is provided so as to penetrate through the temperature adjustment base member in the thickness direction. An insulator made of ceramics and having cooling gas introduction holes is bonded into the hole through an adhesive. By providing the insulator within the temperature adjusting base member in this manner, the temperature adjusting base member is insulated (see, for example, Patent Documents 1 to 4).

Patent No. 4095842 Patent No. 4413667 Registered utility model No. 3154692 Patent No. 5829509

As the structure and materials of semiconductor devices evolve, wafer processing conditions are also changing, so the temperature range in which electrostatic chuck devices can be used tends to be wider. The base member for temperature adjustment and the electrostatic chuck member have a large difference in coefficient of thermal expansion, so due to temperature changes in the electrostatic chuck device, the base member for temperature adjustment and the electrostatic chuck member have a large difference in thermal expansion coefficient. Shear displacement and shear stress occur. When the operating temperature range of the electrostatic chuck device is further expanded, the above-mentioned shear displacement and shear stress increase, and the bonding layer that joins the temperature adjustment base member and the electrostatic chuck member may break.

Furthermore, in the electrostatic chuck device, the thermal resistance between the electrostatic chuck member and the temperature adjusting base member is different between the area directly above the temperature adjusting base member and the area directly above the insulator. If the amount of heat applied from the outside is the same, the temperature difference between the electrostatic chuck member and the temperature adjustment base member is proportional to the thermal resistance between the electrostatic chuck member and the temperature adjustment base member. Therefore, there is a problem in that the temperature of the plate-shaped sample such as a wafer directly above the insulator is different from the temperature of the plate-shaped sample in a region other than directly above the insulator.

The present invention has been made in view of the above circumstances, and suppresses the generation of shear displacement and shear stress in the temperature adjustment base member and the electrostatic chuck member due to the difference in thermal expansion between them. Another object of the present invention is to provide an electrostatic chuck device that can uniformize the temperature of a plate-shaped sample fixed on an electrostatic chuck member.

In order to solve the above problems, one embodiment of the present invention provides an electrostatic chuck device in which an electrostatic chuck member made of ceramics and a temperature adjustment base member made of metal are bonded via a bonding layer. A cooling gas introduction hole is provided in the electrostatic chuck member, the temperature adjustment base member, and the bonding layer in the thickness direction, and a housing hole is provided in the temperature adjustment base member in the thickness direction. An insulator made of ceramic is bonded therein via the bonding layer, and the cooling gas introduction hole in the temperature adjustment base member is a through hole that penetrates the insulator in the thickness direction arranged in the accommodation hole. an end surface of the insulator on the electrostatic chuck member side is in the accommodation hole, and the thickness of the bonding layer between the electrostatic chuck member and the temperature adjustment base member is 0.05 mm or more, and 0.20 mm or less, and a thickness of a portion of the bonding layer between the insulator and the electrostatic chuck member located within the accommodation hole is 0.0 mm or more and 0.2 mm or less, and the electrostatic chuck The bonding layer between the member and the temperature regulating base member is made of a silicone resin composition containing a silicone resin and a filler, and the bonding layer between the insulator and the temperature regulating base member is made of a silicone resin composition containing a silicone resin and a filler. The inner portion provides an electrostatic chuck device that includes a layer consisting solely of silicone resin .

In one aspect of the present invention, the thickness of the bonding layer between the insulator and the temperature adjustment base member within the accommodation hole may be greater than 0.00 mm and less than or equal to 0.05 mm.

In one aspect of the present invention, the bonding layer between the electrostatic chuck member and the temperature adjustment base member may be made of a polymeric material having a Young's modulus of 8 MPa or less after curing.

In one aspect of the present invention, the thickness of the bonding layer between the electrostatic chuck member and the temperature adjustment base member is such that the thickness of the bonding layer between the insulator and the electrostatic chuck member is within the accommodation hole of the bonding layer between the insulator and the electrostatic chuck member. The thickness of the bonding layer between the insulator and the temperature adjusting base member may be greater than or equal to the thickness of the portion within the accommodation hole.

In one aspect of the present invention, the bonding layer between the insulator and the electrostatic chuck member may be made of a silicone resin composition containing a filler.

According to the present invention, the generation of shear displacement and shear stress due to the difference in thermal expansion between the temperature adjustment base member and the electrostatic chuck member is suppressed, and the temperature adjustment base member and the electrostatic chuck member are fixed on the electrostatic chuck member. An electrostatic chuck device capable of uniformizing the temperature of a plate-shaped sample can be provided.

1 is a sectional view showing an electrostatic chuck device according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a bonding layer of an electrostatic chuck device according to an embodiment of the present invention. 1 is a sectional view showing an electrostatic chuck device according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing a method for evaluating the thermal uniformity of an electrostatic chuck device in Examples and Comparative Examples. FIG. 2 is a schematic diagram showing a method of temperature cycle testing of an electrostatic chuck device in Examples and Comparative Examples.

An embodiment of an electrostatic chuck device of the present invention will be described.
It should be noted that the present embodiment is specifically explained in order to better understand the gist of the invention, and is not intended to limit the invention unless otherwise specified.

<Electrostatic chuck device>
The electrostatic chuck device according to this embodiment will be described below with reference to FIGS. 1 to 3.
Note that in all the drawings below, the dimensions, ratios, etc. of each component are changed as appropriate to make the drawings easier to read.

FIG. 1 is a sectional view showing an electrostatic chuck device according to an embodiment of the present invention. As shown in FIG. 1, the electrostatic chuck device 1 includes a disk-shaped electrostatic chuck member 2, a disk-shaped temperature adjustment base member 3 that adjusts the electrostatic chuck member 2 to a desired temperature, and It has a bonding layer 4 that bonds and integrates the electrostatic chuck member 2 and the temperature adjustment base member 3.
In the following description, the mounting surface 11a side of the mounting plate 11 may be referred to as "upper" and the temperature adjustment base member 3 side may be referred to as "lower" to indicate the relative position of each component.

[Electrostatic chuck member]
The electrostatic chuck member 2 includes a mounting plate 11 made of ceramic whose upper surface serves as a mounting surface 11a on which a plate-shaped sample such as a semiconductor wafer is placed, and a surface opposite to the mounting surface 11a of the mounting plate 11. A support plate 12 provided on the side, an electrode 13 for electrostatic adsorption held between the placing plate 11 and the support plate 12, and an electrode 13 for electrostatic adsorption held between the placing plate 11 and the support plate 12. It has an annular insulating material 14 surrounding the electrode 13 and a power supply terminal 16 provided in the fixing hole 15 of the support plate 12 so as to be in contact with the electrostatic adsorption electrode 13.

A total of four cooling gas introduction holes 17 are formed in the mounting plate 11, the support plate 12, and the electrostatic adsorption electrode 13 at positions that are rotationally symmetrical with respect to the central axis. .

[Placement plate]
A large number of protrusions (not shown) are provided on the mounting surface 11a of the mounting plate 11 to support a plate-shaped sample such as a semiconductor wafer. Further, a peripheral wall having the same height as the above-mentioned protrusion is formed on the peripheral edge of the mounting surface 11a of the mounting plate 11 to prevent cooling gas such as helium (He) from leaking (not shown). )ing. The inside of this peripheral wall is an adsorption area for electrostatically adsorbing a plate-shaped sample. Cooling gas is supplied through the cooling gas introduction hole 17 to the gap between the mounting surface 11a of the mounting plate 11 and the plate-shaped sample mounted on the top surface of the protrusion.

The ceramic constituting the mounting plate 11 is not particularly limited as long as it is a dielectric material, has mechanical strength, and has durability against corrosive gas and its plasma. Examples of such ceramics include aluminum oxide (Al ₂ O ₃ ) sintered bodies, aluminum nitride (AlN) sintered bodies, aluminum oxide (Al ₂ O ₃ )-silicon carbide (SiC) composite sintered bodies, etc. Suitably used.

The thickness of the mounting plate 11 is preferably 0.3 mm or more and 3.0 mm or less, more preferably 0.5 mm or more and 1.5 mm or less. If the thickness of the mounting plate 11 is 0.3 mm or more, it has excellent voltage resistance. On the other hand, if the thickness of the mounting plate 11 is 3.0 mm or less, the electrostatic adsorption force of the electrostatic chuck member 2 will not decrease, and the plate placed on the mounting surface 11a of the mounting plate 11 will not be reduced. The temperature of the plate-shaped sample during processing can be maintained at a preferable constant temperature without reducing the thermal conductivity between the plate-shaped sample and the temperature adjustment base member 3.

[Support plate]
The support plate 12 supports the mounting plate 11 and the electrostatic adsorption electrode 13 from below.

The support plate 12 is made of the same material as the ceramic that constitutes the mounting plate 11.
The thickness of the support plate 12 is preferably 0.3 mm or more and 3.0 mm or less, more preferably 0.5 mm or more and 1.5 mm or less. If the thickness of the support plate 12 is 0.3 mm or more, sufficient withstand voltage can be ensured. On the other hand, if the thickness of the support plate 12 is 3.0 mm or less, the electrostatic adsorption force of the electrostatic chuck member 2 will not be reduced, and the plate shape placed on the mounting surface 11a of the mounting plate 11 will be The temperature of the plate-shaped sample during processing can be maintained at a preferable constant temperature without reducing the thermal conductivity between the sample and the temperature adjustment base member 3.

[Electrostatic adsorption electrode]
By applying a voltage to the electrostatic adsorption electrode 13, an electrostatic adsorption force is generated to hold the plate-shaped sample on the mounting surface 11a of the mounting plate 11.

Suitable materials for forming the electrostatic adsorption electrode 13 include high melting point metals such as titanium, tungsten, molybdenum, and platinum, carbon materials such as graphite and carbon, and conductive ceramics such as silicon carbide, titanium nitride, and titanium carbide. used for. It is desirable that the coefficient of thermal expansion of these materials be as close as possible to the coefficient of thermal expansion of the mounting plate 11.

The thickness of the electrostatic adsorption electrode 13 is preferably 5 μm or more and 200 μm or less, more preferably 10 μm or more and 100 μm or less. If the thickness of the electrostatic adsorption electrode 13 is 5 μm or more, sufficient conductivity can be ensured. On the other hand, if the thickness of the electrostatic adsorption electrode 13 is 200 μm or less, the thermal conductivity between the plate-shaped sample placed on the mounting surface 11a of the mounting plate 11 and the temperature adjustment base member 3 will be reduced. The temperature of the plate-shaped sample during processing can be maintained at a desired constant temperature without any drop in temperature. Furthermore, plasma can be stably generated without decreasing plasma permeability.

The electrostatic adsorption electrode 13 can be easily formed by a film forming method such as a sputtering method or a vapor deposition method, or a coating method such as a screen printing method.

[Insulating material]
The insulating material 14 surrounds the electrostatic adsorption electrode 13 and protects the electrostatic adsorption electrode 13 from corrosive gas and its plasma.
The insulating material 14 is made of an insulating material having the same composition or the same main component as the mounting plate 11 and the support plate 12. The mounting plate 11 and the support plate 12 are joined and integrated by the insulating material 14 via the electrostatic adsorption electrode 13.

[Power supply terminal]
The power supply terminal 16 is for applying voltage to the electrostatic adsorption electrode 13.
The number, shape, etc. of the power supply terminals 16 are determined depending on the form of the electrostatic adsorption electrode 13, that is, whether it is a monopolar type or a bipolar type.

The material of the power supply terminal 16 is not particularly limited as long as it is a conductive material with excellent heat resistance. The material for the power supply terminal 16 is preferably a material whose thermal expansion coefficient is close to that of the electrostatic adsorption electrode 13 and the support plate 12, such as a metal material such as Kovar alloy, niobium (Nb), etc. Various conductive ceramics are suitably used.

[Temperature adjustment base member]
The temperature adjustment base member 3 is a thick disc-shaped member made of at least one of metal and ceramics. The frame of the temperature adjustment base member 3 is configured to also serve as an internal electrode for plasma generation. A flow path (not shown) for circulating a cooling medium such as water, He gas, _N2 gas, etc. is formed inside the frame of the temperature adjustment base member 3. Further, a fixing hole 15 is also formed inside the frame of the temperature adjusting base member 3, similarly to the electrostatic chuck member 2. Furthermore, an accommodation hole 18 is formed inside the frame of the temperature adjustment base member 3, which penetrates the temperature adjustment base member 3 in the thickness direction.

A bonding layer 4 that joins and integrates the electrostatic chuck member 2 and the temperature control base member 3 extends into the accommodation hole 18 provided in the temperature control base member 3 . , an insulator 21 made of ceramics is bonded and integrated into the housing hole 18.
A through hole 22 is formed in the insulator 21, passing through the center of the insulator 21 in the thickness direction thereof. The through hole 22 provided in the insulator 21 communicates with the cooling gas introduction hole 17 provided in the electrostatic chuck member 2 and the bonding layer 4 . That is, the cooling gas introduction hole 17 in the temperature adjustment base member 3 is a through hole 22 that penetrates the insulator 21 arranged in the accommodation hole 18 in the thickness direction.

An end surface (upper surface) 21 a of the insulator 21 on the electrostatic chuck member side is located within the accommodation hole 18 . That is, with reference to the surface 3b of the temperature adjustment base member 3 opposite to the electrostatic chuck member 2 (hereinafter referred to as "the other surface"), the upper surface 21a of the insulator 21 is the same as the temperature adjustment base member 3. It exists below one surface 3a of.

The body of the temperature adjustment base member 3 is connected to an external high frequency power source 31. Further, a power supply terminal 16 whose outer periphery is surrounded by an insulating material 32 is fixed in the fixing hole 15 of the temperature adjustment base member 3 via the insulating material 32. The power supply terminal 16 is connected to an external DC power supply 33.

The material constituting the temperature adjustment base member 3 is not particularly limited as long as it is a metal with excellent thermal conductivity, electrical conductivity, and workability, or a composite material containing these metals. As a material constituting the temperature adjustment base member 3, aluminum (Al), copper (Cu), stainless steel (SUS), etc. are preferably used, for example.
At least the surface of the temperature adjusting base member 3 that is exposed to plasma is preferably subjected to an alumite treatment or a resin coating using a polyimide resin. Moreover, it is more preferable that the entire surface of the temperature adjustment base member 3 is subjected to the alumite treatment or resin coating described above.

By subjecting the temperature adjustment base member 3 to alumite treatment or resin coating, the plasma resistance of the temperature adjustment base member 3 is improved and abnormal discharge is prevented. Therefore, the plasma resistance stability of the temperature adjustment base member 3 is improved, and the occurrence of surface scratches on the temperature adjustment base member 3 can also be prevented.

The material constituting the insulator 21 is preferably a ceramic that has durability against plasma and radicals (free radicals). Examples of this ceramic include aluminum nitride (AlN), aluminum oxide (Al ₂ O ₃ ), and silicon nitride (Si). _3N4 ), zirconium oxide ( _ZrO2 ) _, Sialon, boron nitride (BN), and silicon carbide (SiC), or composite ceramics containing two or more of them are preferably used.

[Joining layer]
As shown in FIG. 2, the bonding layer 4 is made of a composite material 41 containing a cured silicone resin composition and a filler, and ceramics having a polygonal shape when the electrostatic chuck member 2 is viewed from above. A plurality of spacers 42 are arranged substantially regularly in the same plane at a substantially constant density. Viewing the electrostatic chuck member 2 in a plan view means viewing the electrostatic chuck member 2 from the mounting surface 11a side of the mounting plate 11. Further, the bonding layer 4 extends into the accommodation hole 18 provided in the temperature adjustment base member 3, and joins and integrates the insulator 21 into the accommodation hole 18. Furthermore, like the electrostatic chuck member 2, fixing holes 15 and cooling gas introduction holes 17 are also formed inside the bonding layer 4.

In FIG. 2, eight spacers 42 are arranged at equal intervals on the outermost concentric circle, eight spacers 42 are arranged at equal intervals on the innermost concentric circle, and four spacers are arranged at equal intervals on the innermost concentric circle. . These spacers 42 are arranged so as not to be lined up in a straight line.

The thickness t1 of the bonding layer 4 between the electrostatic chuck member 2 and the temperature adjustment base member 3 is more than 0.05 mm and less than 0.20 mm, preferably more than 0.10 mm and less than 0.15 mm. .
When the thickness t1 of the bonding layer 4 between the electrostatic chuck member 2 and the temperature adjustment base member 3 is 0.05 mm or less, it is due to the difference in thermal expansion coefficient between the electrostatic chuck member 2 and the temperature adjustment base member 3. The shear strain cannot be sufficiently alleviated, and the electrostatic chuck member may be destroyed. On the other hand, if the thickness t1 of the bonding layer 4 between the electrostatic chuck member 2 and the temperature adjustment base member 3 exceeds 0.20 mm, the thermal resistance of the bonding layer increases, and the plate-shaped sample on the mounting surface 11a increases. cannot be cooled sufficiently.

The thickness t2 of the portion of the bonding layer 4 between the insulator 21 and the electrostatic chuck member 2 within the accommodation hole 18 is 0.0 mm or more and 0.2 mm or less, and 0.0 mm or more and 0.1 mm or less. It is preferable.
When the thickness t2 of the portion of the bonding layer 4 between the insulator 21 and the electrostatic chuck member 2 located inside the accommodation hole 18 is less than 0.0 mm, the end surface 21a of the insulator 21 is on one side of the temperature adjustment base member 3. Since it is above the surface 3a, shear stress caused by the difference in thermal expansion between the electrostatic chuck member 2 and the temperature adjustment base member 3 concentrates on the bonding layer 4 near the insulator end surface 21a, causing cracks in the bonding layer 4. There are concerns. On the other hand, if the thickness t2 of the portion of the bonding layer 4 between the insulator 21 and the electrostatic chuck member 2 within the accommodation hole 18 exceeds 0.2 mm, the thermal resistance of the bonding layer becomes too large and The temperature directly above the insulator becomes high, and temperature uniformity is impaired.

In the accommodation hole 18, the thickness t3 of the bonding layer 4 between the insulator 21 and the temperature adjustment base member 3 is preferably more than 0.00 mm and less than 0.05 mm.
If the thickness t3 of the bonding layer 4 between the insulator 21 and the electrostatic chuck member 2 is 0.00 mm, the thermal resistance of the bonding layer becomes too small, and the temperature of the plate-shaped sample directly above the insulator decreases. On the other hand, if the thickness t3 of the bonding layer 4 between the insulator 21 and the electrostatic chuck member 2 exceeds 0.05 mm, the thermal resistance of the bonding layer becomes too large and the temperature immediately above the insulator in the plate-shaped sample increases. temperature becomes high, and temperature uniformity is impaired.

The thickness t1 of the bonding layer 4 between the electrostatic chuck member 2 and the temperature adjustment base member 3 is the thickness t2 of the portion of the bonding layer 4 between the insulator 21 and the electrostatic chuck member 2 located inside the accommodation hole 18. In addition, it is preferable that the thickness is larger than the thickness t3 of the bonding layer 4 between the insulator 21 and the temperature adjustment base member 3 in the accommodation hole 18.
The thickness t1 of the bonding layer 4 between the electrostatic chuck member 2 and the temperature adjustment base member 3 is defined as the thickness t2 of the portion of the bonding layer 4 located within the accommodation hole 18 between the insulator 21 and the electrostatic chuck member 2. By doing the above, shear strain due to the difference in thermal expansion coefficient between the electrostatic chuck member 2 and the temperature adjustment base member 3 can be sufficiently alleviated. Also, the thickness t1 of the bonding layer 4 between the electrostatic chuck member 2 and the temperature adjustment base member 3 is the thickness t1 of the bonding layer 4 between the insulator 21 and the temperature adjustment base member 3 in the accommodation hole 18. By making it larger than t3, the thermal resistance of the bonding layer 4 will not become too large, the temperature directly above the insulator 21 in the plate-shaped sample on the mounting surface 11a will not become too high, and the temperature will be uniform. Maintains sexuality.

The spacer 42 is for joining the electrostatic chuck member 2 and the temperature adjustment base member 3 with a constant thickness. Suitable materials for the spacer 32 include materials that do not have high dielectric loss (tan δ), such as sintered bodies such as alumina (Al ₂ O ₃ ), silicon nitride (Si ₃ N ₄ ), and zirconia (ZrO ₂ ). used for. Note that materials with high dielectric loss such as silicon carbide (SiC) sintered bodies, metal plates such as aluminum (Al), and magnetic materials such as ferrite (Fe ₂ O ₃ ) are not preferred because they cause discharge.

The bonding layer 4 will be described in detail below.
The bonding layer 4 between the electrostatic chuck member 2 and the temperature adjustment base member 3 is preferably made of a polymer material with a Young's modulus of 8 MPa or less after curing, and more preferably made of a polymer material with a Young's modulus of 6 MPa or less after curing. .
Since the bonding layer 4 is made of a polymeric material having a Young's modulus of 8 MPa or less after curing, the thermal resistance of the bonding layer 4 does not become too large, and the insulator in the plate-shaped sample on the mounting surface 11a The temperature directly above 21 does not become too high, and temperature uniformity is maintained.

The Young's modulus of the polymer material constituting the bonding layer 4 after curing is measured by the DMA method. Here, "DMA" refers to dynamic viscoelastic analysis, and is an analysis method defined in JIS C 6481, for example. The measurement conditions were to apply a tensile load of 10 g in the longitudinal direction of the specimen with a span of 40 mm under each measurement temperature condition, and then apply a sine wave in the longitudinal direction with an amplitude of 16 μm and a frequency of 11 Hz to obtain the storage modulus. , that value is taken as Young's modulus.

As the polymer material having a Young's modulus of 8 MPa or less after curing, a silicone resin composition is preferable.
The silicone resin composition includes silicone resins described in known literature (Japanese Patent Laid-Open No. 4-287344). The silicone resin composition may contain a silicone resin and a filler.

As shown in FIG. 3, the bonding layer 4 (4A) between the insulator 21 and the electrostatic chuck member 2 is preferably made of a silicone resin composition containing a filler. This prevents the thermal resistance of the bonding layer 4A from becoming too large, prevents the temperature directly above the insulator 21 in the plate-shaped sample on the mounting surface 11a from becoming too high, and maintains temperature uniformity. It will be done.

Further, the bonding layer 4 (4B) between the electrostatic chuck member 2 and the temperature adjustment base member 3 is preferably made of a silicone resin composition containing a silicone resin and a filler. As a result, the thermal resistance of the bonding layer 4 (4B) does not become too large, the temperature directly above the insulator 21 in the plate-shaped sample on the mounting surface 11a does not become too high, and temperature uniformity is maintained. is maintained.

Moreover, it is preferable that the portion 4C(4) of the bonding layer 4 between the insulator 21 and the electrostatic chuck member 2 temperature adjustment base member 3 within the accommodation hole 18 includes a layer made only of silicone resin. Thereby, the insulator 21 can be firmly fixed to the accommodation hole 18 via the bonding layer 4C(4). Furthermore, it is preferable that the layer made only of silicone resin contained in the bonding layer 4C (4) is in contact with the insulator 21. Thereby, the insulator 21 can be more firmly fixed to the accommodation hole 18 via the bonding layer 4C(4).

This silicone resin is a resin with excellent heat resistance and elasticity, and is a silicon compound polymer having siloxane bonds (Si--O--Si). This silicone resin can be represented by, for example, the following chemical formula (1) and chemical formula (2).

（但し、Ｒは、Ｈまたはアルキル基（Ｃ_ｎＨ_２ｎ＋１－：ｎは整数）である。）

(However, R is H or an alkyl group (C _n H _2n+1 −: n is an integer).)

（但し、Ｒは、Ｈまたはアルキル基（Ｃ_ｎＨ_２ｎ＋１－：ｎは整数）である。）

(However, R is H or an alkyl group (C _n H _2n+1 −: n is an integer).)

As such a silicone resin, it is particularly preferable to use a silicone resin having a thermosetting temperature of 70° C. or higher and 140° C. or lower. If the thermosetting temperature of the silicone resin is 70°C or higher, the silicone resin may start to harden during the joining process when joining the support plate 12 of the electrostatic chuck member 2 and the temperature adjustment base member 3. There is no problem in joining work. On the other hand, if the thermosetting temperature of the silicone resin is 140° C. or lower, the difference in thermal expansion between the support plate 12 and the temperature adjustment base member 3 can be absorbed, so that the mounting surface 11a of the mounting plate 11 can be flat. The level never decreases. Further, the bonding force between the support plate 12 and the temperature adjustment base member 3 does not decrease, and separation between them does not occur.

As the silicone resin, it is preferable to use one having a Young's modulus of 8 MPa or less after curing. If the Young's modulus after curing is 8 MPa or less, it is possible to absorb the difference in thermal expansion between the support plate 12 and the temperature adjustment base member 3 even when the bonding layer 4 is subjected to a thermal cycle of temperature increase and temperature decrease. Therefore, it is possible to prevent the durability of the bonding layer 4 from deteriorating.

The filler is not particularly limited as long as it is a highly thermally conductive material. Examples of highly thermally conductive fillers include ceramic powders such as alumina (Al ₂ O ₃ ), silicon oxide (SiO ₂ ), and aluminum nitride (AlN), and metal powders such as aluminum (Al). As the filler, surface-coated aluminum nitride (AlN) particles, in which a coating layer made of silicon oxide (SiO ₂ ) is formed on the surface of aluminum nitride (AlN) particles, are preferable because they have excellent thermal conductivity.

In addition, surface-coated aluminum nitride ( _AlN ) particles are simply aluminum nitride (AlN ) has excellent water resistance compared to particles. Therefore, the durability of the bonding layer 4 containing the silicone resin composition as a main component can be ensured, and therefore the durability of the electrostatic chuck device 1 can be dramatically improved.

As shown in the chemical reaction formula (3) below, aluminum nitride (AlN) particles without a surface coating are, for example, hydrolyzed by water in the atmosphere to form aluminum hydroxide (Al(OH) ₃ ). and ammonia (NH ₃ ). This aluminum hydroxide (Al(OH) ₃ ) reduces the thermal conductivity of aluminum nitride (AlN).
AlN+ _3H2O →Al(OH) ₃ +NH3 ( ₃ )

On the other hand, surface-coated aluminum nitride (AlN) particles have a surface coated with a coating layer made of silicon oxide (SiO ₂ ) having excellent water resistance. is not hydrolyzed by water in the atmosphere, and the thermal conductivity of aluminum nitride (AlN) does not decrease. Therefore, the durability of the bonding layer 4 is improved, and it does not become a source of contamination to plate-shaped samples such as semiconductor wafers.

Since the surface-coated aluminum nitride (AlN) particles can obtain a strong bond between silicon (Si) and the silicone resin composition in the coating layer, it is possible to improve the elongation of the bonding layer 4. It is possible. Thereby, thermal stress caused by the difference between the coefficient of thermal expansion of the support plate 12 of the electrostatic chuck member 2 and the coefficient of thermal expansion of the temperature adjustment base member 3 can be alleviated, and the electrostatic chuck member 2 and temperature adjustment The base member 3 can be accurately and firmly joined to the base member 3. Further, the electrostatic chuck device has sufficient resistance to thermal cycle loads during use, and the durability of the electrostatic chuck device is improved.

The thickness of the coating layer of the surface-coated aluminum nitride (AlN) particles is preferably 0.005 μm or more and 0.05 μm or less, more preferably 0.005 μm or more and 0.03 μm or less.
If the thickness of the coating layer is 0.005 μm or more, the water resistance (moisture resistance) of aluminum nitride (AlN) can be sufficiently exhibited. On the other hand, if the thickness of the coating layer is 0.05 μm or less, the thermal conductivity of the surface-coated aluminum nitride (AlN) particles will not decrease, and as a result, they will be placed on the placement surface 11a of the placement plate 11. Thermal conductivity between the plate-shaped sample and the temperature adjustment base member 3 does not decrease. Therefore, the temperature of the plate-shaped sample during processing can be maintained at a preferable constant temperature.

The average particle size of the surface-coated aluminum nitride (AlN) particles is preferably 1 μm or more and 20 μm or less.
If the average particle size of the surface-coated aluminum nitride (AlN) particles is less than 1 μm, there is a risk that contact between the particles will be insufficient and the thermal conductivity will deteriorate as a result, and if the particle size is too small, it may be difficult to handle. This is not preferable because it causes a decrease in workability. On the other hand, if the average particle size exceeds 20 μm, the proportion of the silicone resin composition in the bonding layer 4 decreases when viewed locally, which may lead to a decrease in the extensibility and adhesive strength of the bonding layer 4. Yes, and in that case, it is not preferable because particles are likely to detach and pores are created in the bonding layer 4, resulting in deterioration of thermal conductivity, elongation, and adhesive strength. .

The content of surface-coated aluminum nitride (AlN) particles in this bonding layer 4 is preferably 20 vol% or more and 40 vol% or less.
When the content of the surface-coated aluminum nitride (AlN) particles is less than 20 vol%, the thermal conductivity of the bonding layer 4 decreases, and the temperature of the plate-shaped sample placed on the mounting surface 11a of the mounting plate 11 decreases. This is because the thermal conductivity with the adjustment base member 3 decreases, making it difficult to maintain the temperature of the plate-shaped sample during processing at a preferable constant temperature. If the temperature exceeds the limit, the extensibility of the bonding layer 4 decreases and thermal stress relaxation becomes insufficient, which not only deteriorates the flatness and parallelism of the mounting surface 11a of the mounting plate 11, but also deteriorates the flatness and parallelism of the mounting surface 11a of the mounting plate 11. This is because the bonding force between the base member 3 and the base member 3 may decrease, and there is a possibility that separation may occur between the two.

The thickness of this bonding layer 4 is preferably 50 μm or more and 180 μm or less.
If the thickness of the bonding layer 4 is less than 50 μm, the thermal conductivity between the electrostatic chuck member 2 and the temperature adjustment base member 3 will be good, but thermal stress relaxation will be insufficient. This is because if the thickness of the bonding layer 4 exceeds 180 μm, sufficient thermal conductivity between the electrostatic chuck member 2 and the temperature adjustment base member 3 cannot be ensured, and plasma permeability also decreases. .

According to the electrostatic chuck device 1 of this embodiment, the upper surface 21a of the insulator 21 is inside the accommodation hole 18, and the thickness t1 of the bonding layer 4 between the electrostatic chuck member 2 and the temperature adjustment base member 3 is 0. .05 mm or more and 0.20 mm or less, and the thickness t2 of the portion of the bonding layer 4 between the insulator 21 and the electrostatic chuck member 2 inside the accommodation hole 18 is more than 0.0 mm and 0.2 mm or less, so the temperature It is possible to suppress the generation of shear displacement and shear stress in the adjustment base member 3 and the electrostatic chuck member 2 due to the difference in thermal expansion between them.

Hereinafter, a method for manufacturing the electrostatic chuck device 1 of this embodiment will be described with emphasis on a method for joining the electrostatic chuck member 2 and the temperature adjustment base member 3.

First, the electrostatic chuck member 2 and the temperature adjustment base member 3 are manufactured by a known method.

Next, at least one of a silicone resin and a silicone resin composition containing a filler is applied to the side surface of the insulator 21, and a filler-containing silicone resin composition is applied to the upper surface 21a of the insulator 21. Thereafter, the insulator 21 is inserted into the accommodation hole 18 of the temperature adjustment base member 3. At this time, the dimensions of the outer diameter of the insulator 21 and the inner diameter of the accommodation hole 18 are adjusted so that the thickness t3 of the bonding layer 4 between the insulator 21 and the temperature adjustment base member 3 within the accommodation hole 18 becomes a desired dimension. Set.

When inserting the insulator 21, the end surface (upper surface) 21a of the insulator 21 is located below one surface 3a of the temperature adjustment base member 3 and in the accommodation hole of the bonding layer 4 between the insulator 21 and the electrostatic chuck member 2. 18 so that the thickness t2 of the portion 4A (bonding layer 4A) becomes a desired thickness. The positioning is performed by using a jig using the other surface 3b of the temperature adjusting base member 3 as a reference, or by abutting against the insulator 21 and the accommodation hole 18 of the temperature adjusting base member 3 in a stepped manner.

Furthermore, by inserting the insulator 21 into the accommodation hole 18 in a vacuum, it is possible to prevent air from being entrained, and to suppress a decrease in withstand voltage due to air bubbles and uneven heat transfer.

Thereafter, the silicone resin composition is cured. The curing conditions may be in accordance with the optimum curing conditions for the silicone resin.

On the other hand, a silicone resin composition and a filler are mixed at a predetermined ratio, and this mixture is subjected to a stirring defoaming treatment to prepare a mixture of the silicone resin composition and filler. In this case, an organic solvent such as toluene or xylene may be added to the mixture so that the viscosity of the silicone resin composition is within a range suitable for coating, for example, 50 Pa·s or more and 300 Pa·s or less.

Next, the joint surface of the temperature adjustment base member 3 is degreased and cleaned using, for example, acetone, and a ceramic spacer 41 with a width of 1 mm, a length of 1 mm, and a thickness of 0.1 mm is placed on the joint surface. Adhere using room temperature curing silicone adhesive.

The spacer 41 is for joining the electrostatic chuck member 2 and the temperature adjustment base member 3 at a constant interval. The number of spacers 31 and the positions at which they are arranged may be determined as appropriate. For example, when joining an electrostatic chuck member 2 with a diameter of 298 mm and a temperature adjustment base member 3 with a diameter of 298 mm, 8 pieces are placed on the outermost concentric circle on the temperature adjustment base member 3, and Eight pieces are placed on concentric circles closer to the center, and eight pieces are placed on concentric circles closer to the center. These spacers 41 are arranged so as not to be lined up in a straight line. Furthermore, four pieces are arranged on a concentric circle in the center direction, and four pieces are arranged on a concentric circle on the innermost circumference.

Next, the silicone adhesive is left at room temperature for a predetermined period of time to fully cure the room temperature curable silicone adhesive, and then a silicone resin composition forming the bonding layer 4 is applied onto the spacer 41 . The amount of the silicone resin composition to be applied is within a predetermined range in order to join the electrostatic chuck member 2 and the temperature adjustment base member 3 at a constant interval.
For example, when joining an electrostatic chuck member 2 with a diameter of 298 mm and a temperature adjustment base member 3 with a diameter of 298 mm, 20 g to 22 g of the temperature adjustment base member 3 is applied to the joint surface of the electrostatic chuck member 2. Apply 15g to 17g each.

As a method for applying this silicone resin composition, in addition to manual application using a spatula or the like, a bar coating method, a screen printing method, etc. can be used.

After coating, the electrostatic chuck member 2 and the temperature adjustment base member 3 are overlapped with each other via the silicone resin composition, and the distance between the electrostatic chuck member 2 and the temperature adjustment base member 3 is adjusted to the thickness of the spacer 41. The laminate of the electrostatic chuck member 2 and the temperature adjusting base member 3 is crushed until the silicone resin composition is removed, and the excess silicone resin composition is extruded and removed. The temperature during crushing is preferably the temperature at which the silicone resin composition has the highest fluidity.

In addition, in order to remove air bubbles in the silicone resin composition, vacuum defoaming treatment may be performed after the electrostatic chuck member 2 and the temperature adjustment base member 3 are stacked together to form a strong and uniform structure. This is effective in obtaining the bonding layer 4.

Thereafter, the silicone resin composition is cured. The curing conditions may be in accordance with the optimum curing conditions of the silicone resin used, and pressure may be applied during curing.

In this way, the support plate 12 of the electrostatic chuck member 2 and the temperature adjustment plate member 3 are joined, and the average thermal conductivity of the bonding layer 4 formed between the support plate 12 and the temperature adjustment plate member 3 is The value is 0.35 W/mK or more, and the thermal conductivity is excellent.

Note that the plate-shaped sample according to this embodiment is not limited to semiconductor wafers, but may also include, for example, glass substrates for flat panel displays (FPD) such as liquid crystal displays (LCDs), plasma displays (PDPs), and organic EL displays. It may be. Further, the electrostatic chuck device of this embodiment may be designed according to the shape and size of the substrate.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples.

[Example 1]
(Production of electrostatic chuck device)
"Formation of electrostatic chuck member"
The electrostatic chuck member 2 was obtained by joining and integrating the mounting plate 11 and the support plate 12 having the power supply terminal 16 at the center.
Specifically, an electrostatic chuck member 2 having a mounting plate 11 and a support plate 12 shown in FIG. was created.
The mounting plate 11 of this electrostatic chuck member 2 was an aluminum oxide-silicon carbide composite sintered body containing 8% by mass of silicon carbide, and had a disk shape with a diameter of 310 mm and a thickness of 3 mm.

Further, like the mounting plate 11, the support plate 12 was also an aluminum oxide-silicon carbide composite sintered body containing 8% by mass of silicon carbide, and had a disk shape with a diameter of 310 mm and a thickness of 5.0 mm. .

This joined body (electrostatic chuck member 2) was machined into a disk shape with a diameter of 298 mm and a thickness of 1.0 mm.
Thereafter, the electrostatic attraction surface of this mounting plate 11 was made into an uneven surface by forming a large number of protrusions with a height of 50 μm, and the top surface of these protrusions was used as a holding surface for the plate-shaped sample W. . Due to this shape, the joined body was formed so that cooling gas could flow into the groove formed between the concave portion (other than the protrusion on the suction surface) and the electrostatically attracted plate-like sample W. .

"Formation of base member for temperature adjustment"
A disc-shaped temperature adjustment base member 3 made of aluminum and having a diameter of 350 mm and a height of 30 mm was manufactured by machining. A flow path 34 for circulating a refrigerant was formed inside the temperature adjustment base member 3. A plurality of insulator housing holes 18 were formed at cooling gas introduction points. The inner diameter of the accommodation hole 18 was set to 5.0 mm.
One surface 3a side of the temperature adjustment base member 3 of the accommodation hole 18 was chamfered to a diameter of C0.05 mm.

"Preparation of silicone resin composition"
Surface-coated aluminum nitride (AlN) powder (product name: TOYALNITE, Toyo Aluminum) whose surface is coated with silicon oxide (SiO ₂ ) on silicone resin (product name: TSE3221, manufactured by Momentive Performance Materials Japan LLC) Co., Ltd.) was mixed in an amount of 35 vol% based on the total volume of the above silicone resin and surface-coated aluminum nitride (AlN) powder, and this mixture was subjected to stirring and degassing treatment to obtain a silicone resin composition. I got something. The thermal conductivity of this silicone resin composition was 0.8 W/mK.

"Formation of insulators"
An insulator 21 was formed by processing the aluminum oxide sintered body into a tubular shape. At this time, the insulator 21 had an outer diameter of 4.9 mm, an inner diameter of 2.0 mm, and a total length of 29.95 mm.

"Joining of insulators"
Next, a cold-curing silicone adhesive Shin-Etsu Silicone KE4895T (manufactured by Shin-Etsu Chemical Co., Ltd.) was applied to the side surface of the insulator 21, and a filler-containing silicone resin composition was applied to the upper surface 21a of the insulator 21. The silicone resin composition produced as described above was used. Thereafter, the insulator 21 was inserted into the insulator accommodation hole 18 at the cooling gas introduction location of the temperature adjustment base member 3. At that time, the lower end 21b of the insulator 21 and the other end surface 3b of the temperature adjustment base member 3 were positioned and fixed so as to be at the same height. As a result, the upper end portion 21a of the insulator 21 was located within the accommodation hole 18, and the height difference between the upper end portion 21a and the one surface 3a of the temperature adjustment base member 3 was 0.05 mm.

"Formation of spacers"
A rectangular spacer 42 having a width of 1 mm, a length of 1 mm, and a thickness of 0.1 mm was fabricated from an alumina (Al ₂ O ₃ ) sintered body.

"Spacer placement"
The spacer 42 described above was adhered to a predetermined position on the temperature adjustment base member 3 using a room temperature curing silicone adhesive (trade name: Shin-Etsu Silicone KE4895T, manufactured by Shin-Etsu Chemical Co., Ltd.), and the spacer 42 was fixed.

"Formation of bonding layer"
Next, the above silicone resin composition was applied onto the electrostatic chuck member 2 by screen printing.

"Lamination of electrostatic chuck member and base member"
Thereafter, the electrostatic chuck member 2 and the temperature adjustment base member 3 were stacked on each other with the silicone resin composition interposed therebetween.
Next, the bonding layer 4 between the electrostatic chuck member 2 and the temperature adjustment base member 3 is dropped by applying appropriate pressure until the gap becomes the thickness of the spacer 42, and the extruded excess adhesive is removed. , hardened. As a result, the bonding layer thickness t1 between the electrostatic chuck member 2 and the temperature adjustment base member 3 was 0.1 mm.
Further, the thickness t2 of the portion of the bonding layer 4 between the insulator 21 and the electrostatic chuck member 2 located within the accommodation hole 18 was 0.05 mm.

(Heat uniformity evaluation)
The thermal uniformity of the electrostatic chuck device 1 was evaluated using a temperature evaluation substrate 5 as shown in FIG. 5 and a vacuum chamber 6 equipped with an infrared heater.

The temperature evaluation substrate 5 is a silicon carbide (SiC) wafer 51 with a thermocouple 52 attached to it, and can measure the substrate temperature at the position where the thermocouple 52 is attached. The thermocouple 52 is installed at a position directly above the center of the insulator 21 and at a distance of 20 mm from the center of the insulator 21.

The temperature evaluation substrate 5 is electrostatically attracted to the mounting surface 11a of the mounting plate 11 that constitutes the electrostatic chuck member 2 of the electrostatic chuck device 1 attached to the vacuum chamber 6 equipped with an infrared heater. In the vacuum chamber 6, an infrared heater 61 is arranged opposite to the temperature evaluation substrate 5, and the structure is such that the infrared heater 61 heats the temperature evaluation substrate 5. Furthermore, the temperature of the SiC wafer 51 is measured using a thermocouple 52 . The temperature adjustment base member 3 of the electrostatic chuck device 1 is cooled by the coolant 62 .

The measurement procedure is to evacuate the inside of the vacuum chamber 6 to 0.1 Pa or less using the vacuum pump 63, and with the refrigerant 62 at 20° C. flowing through the temperature adjustment base member 3, a predetermined amount of heat input is applied using the infrared heater 61. The temperature evaluation substrate 5 was heated so that the temperature of the SiC wafer 51 at the position of the thermocouple 52 was measured. The results are shown in Table 1.
From the results in Table 1, it was found that the temperature difference between the temperature evaluation substrate 5 directly above the insulator 21 and a location 20 mm away from directly above the insulator 21 was 0.7° C., indicating that the temperature was uniform.

(Temperature cycle test)
Next, the electrostatic chuck device 1 was placed in a thermostatic chamber, and a temperature cycle test was conducted in which the temperature was raised and lowered between -20°C and 130°C to determine the difference in thermal expansion between the electrostatic chuck member 2 and the temperature adjustment base member 3. The bonding layer 4 was repeatedly subjected to displacement caused by the following.

Before and after the temperature cycle test, a withstand voltage test was conducted on the bonding layer 4 using the method shown in FIG. 6.
The electrode pin 72 connected to the DC power supply 71 is inserted into the cooling gas introduction hole 17 of the electrostatic chuck device 1, and the voltage is applied to the electrostatic chuck device 1 by the DC power supply 71 while the temperature adjustment base member 3 is grounded. was applied. The leakage current between the electrode pin 72 and the temperature adjustment base member 3 was measured using an ammeter 73 connected between the temperature adjustment base member 3 and the ground, and the withstand voltage was examined.
The results are shown in Table 2. It was found that the withstand voltage was 10 kV or more even after the temperature cycle test.

[Example 2]
In the same manner as in Example 1, an electrostatic chuck member 2 and a temperature adjustment base member 3 were produced.

"Formation of insulators"
An insulator 21 was formed by processing the aluminum oxide sintered body into a tubular shape. At this time, the outer diameter of the insulator 21 was set to 4.9 mm, and the total length was set to 30.00 mm.

"Joining of insulators"
The temperature adjusting base member 3 and the insulator 21 were joined in the same manner as in Example 1. As a result, the upper end portion 21a of the insulator 21 was located within the accommodation hole 18, and the level difference between the upper end portion 21a and the one surface 3a of the temperature adjustment base member 3 was 0.0 mm.

"Formation of spacers"
A rectangular spacer 42 having a width of 1 mm, a length of 1 mm, and a thickness of 0.05 mm was fabricated from an alumina (Al ₂ O ₃ ) sintered body.

In the same manner as in Example 1, the electrostatic chuck member 2 and the temperature adjustment base member 3 were laminated. As a result, the thickness t1 of the bonding layer 4 between the electrostatic chuck member 2 and the temperature adjustment base member 3 was 0.05 mm.
Further, the thickness t2 of the portion of the bonding layer 4 between the insulator 21 and the electrostatic chuck member 2 located within the accommodation hole 18 was 0.0 mm.

(evaluation)
The thermal uniformity of the electrostatic chuck device 1 was evaluated in the same manner as in Example 1. The results are shown in Table 1. From the results in Table 1, it was found that the temperature difference between the temperature evaluation substrate 5 directly above the insulator 21 and a location 20 mm away from directly above the insulator 21 was 0.5° C., indicating that the temperature was uniform.
Next, in the same manner as in Example 1, the electrostatic chuck device 1 was subjected to a temperature cycle test. The results are shown in Table 2. It was found that the withstand voltage was 10 kV or more even after the temperature cycle test.

[Example 3]
An electrostatic chuck device 1 was produced in the same manner as in Example 1, except that the thickness of the spacer 42 was 0.2 mm, the outer diameter of the insulator 21 was 4.98 mm, and the total length was 29.80 mm. The thickness t1 of the bonding layer between the electrostatic chuck member 2 and the temperature adjustment base member 3 is 0.2 mm. The thickness t2 of a certain portion was 0.20 mm, and the thickness t3 of the bonding layer 4 between the insulator 21 and the temperature adjustment base member 3 was 0.01 mm.

(evaluation)
The thermal uniformity of the electrostatic chuck device 1 was evaluated in the same manner as in Example 1. The results are shown in Table 1. From the results in Table 1, it was found that the temperature difference between the temperature evaluation substrate 5 directly above the insulator 21 and a location 20 mm away from directly above the insulator 21 was 0.9° C., indicating that the temperature was uniform.
Next, in the same manner as in Example 1, the electrostatic chuck device 1 was subjected to a temperature cycle test. The results are shown in Table 2. It was found that the withstand voltage was 10 kV or more even after the temperature cycle test.

[Comparative example 1]
An electrostatic chuck device 1 was produced in the same manner as in Example 1 except that the length of the insulator 21 was 30.05 mm. The thickness t1 of the bonding layer between the electrostatic chuck member 2 and the temperature adjustment base member 3 is 0.1 mm, and the upper end 21a of the insulator 21 protrudes from the accommodation hole 18, and the upper end 21a of the insulator 21 is formed between the insulator 21 and the electrostatic chuck member 2. The thickness t2 of the portion of the bonding layer 4 located within the accommodation hole 18 in the bonding layer 4 is -0.05 mm, and the thickness t3 of the bonding layer 4 between the insulator 21 and the temperature adjustment base member 3 is 0.05 mm. It became 05mm.

(evaluation)
The thermal uniformity of the electrostatic chuck device 1 was evaluated in the same manner as in Example 1. The results are shown in Table 1. From the results in Table 1, it was found that the temperature difference between the temperature evaluation substrate 5 directly above the insulator 21 and a location 20 mm away from directly above the insulator 21 was 0.1° C., indicating that the temperature was uniform.
Next, in the same manner as in Example 1, the electrostatic chuck device 1 was subjected to a temperature cycle test. The results are shown in Table 2. The withstand voltage measurement after the temperature cycle test revealed that the discharge was at 9 kV, and the withstand voltage of the bonding layer 4 decreased due to displacement caused by the difference in thermal expansion between the electrostatic chuck member 2 and the temperature adjustment base member 3.

[Comparative example 2]
An electrostatic chuck device 1 was produced in the same manner as in Example 1 except that the total length of the insulator 21 was 29.70 mm. The thickness t1 of the bonding layer between the electrostatic chuck member 2 and the temperature adjustment base member 3 is 0.1 mm, and the thickness of the portion of the bonding layer 4 between the insulator 21 and the electrostatic chuck member 2 within the accommodation hole 18 is 0.1 mm. The thickness t2 was 0.10 mm, and the thickness t3 of the bonding layer 4 between the insulator 21 and the temperature adjustment base member 3 was 0.05 mm.

(evaluation)
The thermal uniformity of the electrostatic chuck device 1 was evaluated in the same manner as in Example 1. The results are shown in Table 1. From the results in Table 1, the temperature difference between the temperature evaluation board 5 directly above the insulator 21 and a location 20 mm away from directly above the insulator 21 is 1.6°C, and the temperature directly above the insulator 21 is high and uneven. That's what I found out.
Next, in the same manner as in Example 1, the electrostatic chuck device 1 was subjected to a temperature cycle test. The results are shown in Table 2. It was found that the withstand voltage was 10 kV or more even after the temperature cycle test.

[Comparative example 3]
An electrostatic chuck device 1 was produced in the same manner as in Example 1, except that the thickness of the spacer 42 was 0.3 mm, the total length of the insulator 21 was 29.80 mm, and the outer diameter was 4.86 mm. The thickness t1 of the bonding layer between the electrostatic chuck member 2 and the temperature adjustment base member 3 is 0.3 mm, and the thickness of the portion of the bonding layer 4 between the insulator 21 and the electrostatic chuck member 2 within the accommodation hole 18 is 0.3 mm. The thickness t2 was 0.20 mm, and the thickness t3 of the bonding layer 4 between the insulator 21 and the temperature adjustment base member 3 was 0.07 mm.

(evaluation)
The thermal uniformity of the electrostatic chuck device 1 was evaluated in the same manner as in Example 1. The results are shown in Table 1. From the results in Table 1, the temperature difference between directly above the insulator 21 of the temperature evaluation board 5 and a location 20 mm away from directly above the insulator 21 is 1.4°C, and the temperature directly above the insulator 21 is as high as 51.3°C. , was found to be non-uniform.
Next, in the same manner as in Example 1, the electrostatic chuck device 1 was subjected to a temperature cycle test. The results are shown in Table 2. It was found that the withstand voltage was 10 kV or more even after the temperature cycle test.

The electrostatic chuck device of the present invention includes an electrostatic chuck member made of ceramics and a temperature adjustment base member made of metal and/or ceramics, the surface of which is coated with a silicone resin composition and silicon oxide (SiO ₂ ). Since it is bonded and integrated by a bonding layer containing surface-coated aluminum nitride (AlN) particles, it can be used with a member made of ceramics and a member made of at least one of metal and ceramics, other than the electrostatic chuck device. It can also be applied to joining and integrating materials, and its usefulness is extremely large.

1 Electrostatic chuck device 2 Electrostatic chuck member 3 Temperature adjustment base member 4 Bonding layer 11 Placement plate 11a Placement surface 12 Support plate 13 Electrostatic adsorption electrode 14 Insulating material 15 Fixing hole 16 Power supply terminal 17 Cooling gas introduction hole 18 Accommodation hole 21 Insulator 22 Through hole 31 High frequency power source 32 Insulating material 33 DC power source 41 Composite material 42 Spacer

Claims (5)

An electrostatic chuck device in which an electrostatic chuck member made of ceramics and a temperature adjustment base member made of metal are bonded via a bonding layer,
Cooling gas introduction holes are provided in the electrostatic chuck member, the temperature adjustment base member, and the bonding layer in a thickness direction thereof;
An insulator made of ceramics is bonded to the accommodation hole passing through the temperature adjustment base member in the thickness direction via the bonding layer,
The cooling gas introduction hole in the temperature adjustment base member is a through hole that penetrates the insulator disposed in the accommodation hole in the thickness direction,
an end surface of the insulator on the electrostatic chuck member side is within the accommodation hole;
The thickness of the bonding layer between the electrostatic chuck member and the temperature adjustment base member is 0.05 mm or more and 0.20 mm or less,
The thickness of the portion of the bonding layer between the insulator and the electrostatic chuck member located within the accommodation hole is 0.0 mm or more and 0.2 mm or less,
The bonding layer between the electrostatic chuck member and the temperature adjustment base member is made of a silicone resin composition containing a silicone resin and a filler,
In the electrostatic chuck device, a portion of the bonding layer between the insulator and the temperature adjusting base member that is located within the accommodation hole includes a layer made only of silicone resin . The electrostatic chuck device according to claim 1, wherein the thickness of the bonding layer between the insulator and the temperature adjustment base member in the accommodation hole is greater than 0.00 mm and less than or equal to 0.05 mm. 3. The electrostatic chuck device according to claim 1, wherein the bonding layer between the electrostatic chuck member and the temperature adjustment base member is made of a polymeric material having a Young's modulus of 8 MPa or less after curing. The thickness of the bonding layer between the electrostatic chuck member and the temperature adjustment base member is greater than or equal to the thickness of the portion of the bonding layer between the insulator and the electrostatic chuck member located within the accommodation hole, The electrostatic chuck device according to any one of claims 1 to 3, wherein the thickness is greater than the thickness of the bonding layer between the insulator and the temperature adjustment base member within the accommodation hole. The electrostatic chuck device according to claim 1, wherein the bonding layer between the insulator and the electrostatic chuck member is made of a silicone resin composition containing a filler.

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