JP5846186B2 - Electrostatic chuck device and method of manufacturing electrostatic chuck device - Google Patents

Description

  The present invention relates to an electrostatic chuck device, and more particularly, is used suitably when a plate-like sample such as a semiconductor wafer is adsorbed and fixed by electrostatic force, and is used in physical vapor deposition (PVD) and chemical vapor deposition in a semiconductor manufacturing process. It is possible to increase the uniformity of the in-plane temperature on the mounting surface on which the plate-like sample is placed in various processes such as film formation by phase growth (CVD), etching such as plasma etching, and exposure. In addition, the present invention relates to an electrostatic chuck device that can increase the voltage resistance of a heating member.

In recent years, in semiconductor manufacturing processes, further improvement of microfabrication technology has been demanded along with higher integration and higher performance of elements. In this semiconductor manufacturing process, the etching technique is an important one of the microfabrication techniques. In recent years, the plasma etching technique capable of high-efficiency and large-area microfabrication has become the mainstream among the etching techniques. .
This plasma etching technique is a kind of dry etching technique. A mask pattern is formed with a resist on a solid material to be processed, and this solid material is supported in a vacuum. By introducing and applying a high-frequency electric field to this reactive gas, the accelerated electrons collide with gas molecules to form a plasma state, and radicals (free radicals) and ions generated from this plasma react with the solid material. This is a technique for forming a fine pattern in a solid material by removing it as a reaction product.

On the other hand, there is a plasma CVD method as one of thin film growth techniques in which source gases are combined by the action of plasma and the obtained compound is deposited on a substrate. This method is a film forming method in which plasma discharge is performed by applying a high-frequency electric field to a gas containing source molecules, source molecules are decomposed by electrons accelerated by the plasma discharge, and the obtained compound is deposited. . Reactions that did not occur only at thermal excitation at low temperatures are also possible in the plasma because the gases in the system collide with each other and are activated to become radicals.
2. Description of the Related Art Conventionally, in a semiconductor manufacturing apparatus using plasma such as a plasma etching apparatus and a plasma CVD apparatus, an electrostatic chuck apparatus is used as an apparatus for simply mounting and fixing a wafer on a sample stage and maintaining the wafer at a desired temperature. Is used.

By the way, in the conventional plasma etching apparatus, when the wafer fixed to the electrostatic chuck apparatus is irradiated with plasma, the surface temperature of the wafer rises. Therefore, in order to suppress the rise in the surface temperature, a cooling medium such as water is circulated through the temperature adjustment base portion of the electrostatic chuck device to cool the wafer from the lower side. A temperature distribution occurs. For example, the temperature increases at the center of the wafer and decreases at the edge.
In addition, a difference occurs in the in-plane temperature distribution of the wafer due to differences in the structure and method of the plasma etching apparatus.

Thus, an electrostatic chuck device with a heater function in which a heater member is attached between the electrostatic chuck portion and the temperature adjusting base portion has been proposed (Patent Document 1).
Since this electrostatic chuck device with a heater function can create a temperature distribution locally within the wafer, the wafer surface temperature distribution can be set on the wafer by setting it according to the film deposition rate and plasma etching rate. Thus, local film formation such as pattern formation and local plasma etching can be performed efficiently.

As a method of attaching the heater to the electrostatic chuck device, a heater material is incorporated in a ceramic electrostatic chuck, or the heater material is applied to the back side of the electrostatic chuck adsorption surface, that is, the back surface of the ceramic plate by screen printing. There is a method of attaching a heater by applying in a predetermined pattern and heating and curing, or a method of attaching a heater by sticking a metal foil or a sheet-like conductive material on the back surface of the ceramic plate-like body, etc. .
Then, the electrostatic chuck device with a heater function can be obtained by bonding and integrating the electrostatic chuck portion with a built-in heater or attached with the heater and the temperature adjusting base portion using an organic adhesive.

JP 2008-300491 A

By the way, a method of attaching a heater by applying a heater material in a predetermined pattern by screen printing on the back side of the suction surface of the conventional electrostatic chuck described above, that is, the back side of the ceramic plate, or by heating and curing, or In the electrostatic chuck device with a heater function by a method of sticking a metal foil or a sheet-like conductive material on the back surface of the ceramic plate-like body, an organic adhesive is used to connect the electrostatic chuck portion and the temperature adjustment base portion. When bonded and integrated, fine pores called pores are formed in the organic adhesive layer, or unbonded parts called repellants are formed between the organic adhesive layer, the electrostatic chuck portion, and the temperature adjusting base portion. If a voltage is applied to the heater, the electrostatic chuck part and the temperature adjustment base part may become conductive (short circuit failure), which may cause dielectric breakdown. There is a problem in that.
In addition, when ensuring insulation by the thickness of the adhesive layer, it is difficult to reduce the thickness of the organic adhesive layer, and the thickness of the organic adhesive layer varies. There is a problem that the in-plane temperature of the surface on which the wafer is placed cannot be made sufficiently uniform.

  Moreover, in the electrostatic chuck device with a heater function using a metal foil or a sheet-like conductive material, a step is generated between the portion where the metal foil or the sheet-like conductive material is pasted as the heater pattern and the portion where there is no heater pattern. If it is bonded only to the cooling base, it will not be possible to cover the unevenness of the heater, and voids etc. will easily occur in the adhesive layer, and even if a thermoplastic sheet-like adhesive is used, there are parts with and without a heater As a result, there is a problem in that a hole is formed at the boundary of the substrate and there is a risk of electric discharge and separation, and the controllability of the in-plane temperature distribution of the electrostatic chuck is deteriorated due to variations in heat transfer between the heater and the cooling base. .

  The present invention has been made in view of the above-described circumstances, and prevents dielectric breakdown between the electrostatic chuck portion and the temperature adjusting base portion and improves the voltage resistance. This improves the uniformity of the in-plane temperature of the mounting surface of the plate-like sample at the same time and applies a more uniform voltage between the electrostatic chuck and the temperature adjusting base to It is an object of the present invention to provide an electrostatic chuck device capable of improving the voltage resistance of a provided heating member.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors bonded a thin heating member to the main surface opposite to the mounting surface of the electrostatic chuck portion through an adhesive, The whole or part of the surface of the adjustment base portion on the electrostatic chuck portion side is covered with a sheet-like or film-like insulating material, and the electrostatic chuck portion and the temperature adjustment base portion are cured with a liquid adhesive. Adhesion and integration through an insulating organic adhesive layer can prevent dielectric breakdown between the electrostatic chuck portion and the temperature adjusting base portion and improve the voltage resistance. It has been found that the uniformity of the in-plane temperature of the mounting surface of the electrostatic chuck portion can be improved and the withstand voltage of the heating member can be improved, and the present invention has been completed. .

In other words, the electrostatic chuck device according to claim 1 of the present invention has an electrostatic chuck portion in which one main surface is a mounting surface on which a plate-like sample is mounted and an internal electrode for electrostatic adsorption is built in, and the static chuck device. A temperature adjusting base portion for adjusting the electric chuck portion to a desired temperature, and a heating member is bonded to a main surface opposite to the placement surface of the electrostatic chuck portion via an adhesive, The whole or part of the surface of the temperature adjusting base portion on the electrostatic chuck portion side is covered with a sheet-like or film-like insulating material, and the heating chuck is bonded to the electrostatic chuck portion, and the sheet-like or film-like surface. The temperature adjusting base portion covered with the insulating material is bonded and integrated through an insulating organic adhesive layer formed by curing a liquid adhesive, and the heating members are two independent from each other. A heater consisting of the above heater pattern. A data element, the adhesive, the are formed in the same pattern overlapping with the heater element in a plan view, irregularities with the heater element and the adhesive material is formed by being laminated, the organic It is embedded in the adhesive layer .

  In this electrostatic chuck apparatus, the electrostatic chuck portion and the temperature adjusting base portion are bonded and integrated through an insulating organic adhesive layer formed by curing a liquid adhesive, thereby providing an insulating property. The organic adhesive layer maintains good insulation between the electrostatic chuck portion and the temperature adjusting base portion. As a result, there is no possibility of conduction (short circuit failure) between the electrostatic chuck portion and the temperature adjustment base portion, and as a result, there is a risk of dielectric breakdown between the electrostatic chuck portion and the temperature adjustment base portion. The withstand voltage between them is improved.

  In addition, a heating member is bonded to the main surface opposite to the mounting surface of the electrostatic chuck portion through an adhesive, and the entire or part of the surface of the temperature adjusting base portion on the electrostatic chuck portion side is formed into a sheet shape. Alternatively, by covering with a film-like insulating material, the interval between the electrostatic chuck portion and the heating member and the interval between the heating member and the temperature adjusting base portion are kept constant, and the surface on the mounting surface of the electrostatic chuck portion The uniformity of the internal temperature is increased, and the voltage resistance of the heating member and the temperature adjusting base is further improved.

  In addition, an insulating organic adhesive layer is interposed between the electrostatic chuck portion to which the heating member is bonded and the temperature adjusting base portion, so that the plate-like sample to be placed can be rapidly raised and lowered. Even in this case, the organic adhesive layer functions as a buffer layer that relieves rapid expansion / contraction of the electrostatic chuck portion, and prevents the electrostatic chuck portion from being cracked or chipped. Thereby, the durability of the electrostatic chuck portion is improved.

The organic adhesive layer may have a Young's modulus of 1 GPa or less.

The electrostatic chuck device according to claim 3 is the electrostatic chuck device according to claim 1 or 2, wherein the adhesive is a silicone-based or acrylic-based adhesive having a Young's modulus after curing of 8 MPa or less. Features.
In this electrostatic chuck device, the adhesive is made of a silicone or acrylic adhesive having a Young's modulus after curing of 8 MPa or less, so that the thermal stress of the electrostatic chuck portion and the heater portion is reduced and durability is improved. Further improve.

  The electrostatic chuck device according to claim 4 is the electrostatic chuck device according to any one of claims 1 to 3, wherein the heating member is formed by etching a non-magnetic metal thin plate by a photolithography method. Features.

The electrostatic chuck device according to claim 5 is the electrostatic chuck device according to any one of claims 1 to 4, wherein the sheet-like or film-like insulating material is formed by a sheet-like or film-like adhesive. It is characterized in that it is bonded to a temperature adjusting base part.
In this electrostatic chuck device, a sheet-like or film-like insulating material is bonded to a temperature-adjusting base portion using a sheet-like or film-like adhesive, so that the temperature-adjusting base portion of the electrostatic chuck portion side Thus, the insulating property is maintained, and the thickness of the adhesive is made constant, so that the uniformity of the in-plane temperature on the mounting surface of the electrostatic chuck portion is increased.

The electrostatic chuck device according to a sixth aspect is the electrostatic chuck device according to any one of the first to fifth aspects, wherein the thickness variation of the adhesive is 10 μm or less.
In this electrostatic chuck device, since the variation in the thickness of the adhesive is set to 10 μm or less, the distance between the electrostatic chuck portion and the heating member is controlled with an accuracy of 10 μm or less, and the heating member is heated. The uniformity of the in-plane temperature of the plate sample is improved.

The electrostatic chuck device according to claim 7 is the electrostatic chuck device according to any one of claims 1 to 6, wherein the electrostatic chuck portion includes a mounting plate having one main surface as the mounting surface described above. A mounting plate that is integrated with the mounting plate and supports the mounting plate, and the electrostatic adsorption internal electrode provided between the mounting plate and the supporting plate, It consists of an aluminum oxide-silicon carbide composite sintered body or an yttrium oxide sintered body.
In this electrostatic chuck device, the mounting plate is made of an aluminum oxide-silicon carbide composite sintered body or an yttrium oxide sintered body, thereby improving the durability against corrosive gas and its plasma and maintaining the mechanical strength. Is done.

  According to the electrostatic chuck device of the first aspect of the present invention, the heating member is bonded to the other main surface of the electrostatic chuck portion via the sheet-like or film-like adhesive, and the heating member is bonded. The electrostatic chuck part and the temperature adjustment base covered entirely or partially with an insulating sheet are bonded and integrated through an insulating organic adhesive layer formed by curing a liquid adhesive. The insulation between the electrostatic chuck portion and the temperature adjusting base portion can be satisfactorily maintained by the member, and as a result, dielectric breakdown can be prevented. Therefore, the voltage resistance between the electrostatic chuck portion and the temperature adjusting base portion can be improved.

  According to the electrostatic chuck device of claim 2 of the present invention, the heating member is bonded to the other main surface of the electrostatic chuck portion via the sheet-like or film-like adhesive, and the heating member is bonded. The electrostatic chuck part and the temperature adjustment base covered entirely or partially with an insulating sheet are bonded and integrated through an insulating organic adhesive layer having a Young's modulus of 1 GPa or less obtained by curing a liquid adhesive. As a result, the insulation between the electrostatic chuck portion and the temperature adjusting base portion can be satisfactorily maintained by the insulating member, and as a result, dielectric breakdown can be prevented. Therefore, the voltage resistance between the electrostatic chuck portion and the temperature adjusting base portion can be improved.

  In addition, since the heating member is bonded to the other main surface of the electrostatic chuck portion via a sheet-like or film-like adhesive, the distance between the electrostatic chuck portion and the heating member can be kept constant, and static The uniformity of the in-plane temperature on the mounting surface of the electric chuck portion can be improved. In addition, the withstand voltage between the heating member and the temperature adjusting base can be improved, and even when the temperature adjusting base is used as a plasma electrode, a higher voltage is applied to the temperature adjusting base. Can be applied.

  In addition, since an organic adhesive layer is interposed between the electrostatic chuck portion and the temperature adjustment base portion, the organic adhesive layer is a buffer that alleviates rapid expansion / contraction of the electrostatic chuck portion. Therefore, the electrostatic chuck portion can be prevented from being cracked or chipped, and the durability of the electrostatic chuck portion can be improved.

  Furthermore, since the mounting plate constituting the electrostatic chuck portion is made of the aluminum oxide-silicon carbide composite sintered body or the yttrium oxide sintered body, the durability against the corrosive gas and its plasma can be improved. Sufficient strength can be maintained.

It is sectional drawing which shows the electrostatic chuck apparatus of one Embodiment of this invention. It is a top view which shows an example of the heater pattern of the heater element of the electrostatic chuck apparatus of one Embodiment of this invention. It is a figure which shows the in-plane temperature distribution of the silicon wafer at the time of cooling of the electrostatic chuck apparatus of an Example. It is a figure which shows the in-plane temperature distribution of the silicon wafer when hold | maintaining at 50 degreeC of the electrostatic chuck apparatus of an Example. It is a figure which shows the in-plane temperature distribution of the silicon wafer at the time of temperature rising of the electrostatic chuck apparatus of an Example.

The form for implementing the electrostatic chuck apparatus of this invention is demonstrated based on drawing.
This embodiment is specifically described for better understanding of the gist of the invention, and does not limit the present invention unless otherwise specified.

  FIG. 1 is a cross-sectional view showing an electrostatic chuck device according to an embodiment of the present invention. The electrostatic chuck device 1 includes a disk-shaped electrostatic chuck portion 2 and a desired electrostatic chuck portion 2. A thick disc-shaped temperature adjusting base portion 3 to be adjusted to the temperature, an adhesive material 4 having a predetermined pattern adhered to the lower surface (other main surface) of the electrostatic chuck portion 2, and an adhesive material 4 The heater element 5 having the same shape as the adhesive 4 bonded to the lower surface, the insulating member 7 bonded to the upper surface of the temperature adjusting base portion 3 via the adhesive 6, and the lower surface of the electrostatic chuck portion 2 The heater element 5 and the insulating member 7 on the temperature adjusting base 3 are opposed to each other, and are mainly composed of an organic adhesive layer 8 for bonding and integrating them.

  The electrostatic chuck portion 2 has a mounting plate 11 whose upper surface is a mounting surface on which a plate-like sample W such as a semiconductor wafer is mounted, and is integrated with the mounting plate 11 to support the mounting plate 11. The support plate 12, the electrostatic adsorption internal electrode 13 provided between the mounting plate 11 and the support plate 12, the insulating material layer 14 insulating the periphery of the electrostatic adsorption internal electrode 13, and the support plate 12 And a power feeding terminal 15 that applies a DC voltage to the electrostatic adsorption internal electrode 13.

The mounting plate 11 and the support plate 12 have a disk shape with the same shape of the stacked surfaces, and are an aluminum oxide-silicon carbide (Al ₂ O ₃ —SiC) composite sintered body, aluminum oxide (Al _2). Insulation having mechanical strength such as O ₃ ) sintered body, aluminum nitride (AlN) sintered body, yttrium oxide (Y ₂ O ₃ ) sintered body, and durability against corrosive gas and its plasma Made of a sintered ceramic.
A plurality of projections 16 having a diameter smaller than the thickness of the plate-like sample are formed on the placement surface of the placement plate 11, and these projections 16 support the plate-like sample W.

  The total thickness of the mounting plate 11, the support plate 12, the electrostatic adsorption internal electrode 13 and the insulating material layer 14, that is, the thickness of the electrostatic chuck portion 2 is preferably 0.7 mm or more and 3.0 mm or less. The reason is that if the thickness of the electrostatic chuck portion 2 is less than 0.7 mm, the mechanical strength of the electrostatic chuck portion 2 cannot be ensured, while the thickness of the electrostatic chuck portion 2 is 3.0 mm. If the upper limit is exceeded, the heat capacity of the electrostatic chuck portion 2 becomes too large, the thermal response of the plate-like sample W to be placed deteriorates, and further, the heat transfer in the lateral direction of the electrostatic chuck portion increases, This is because it becomes difficult to maintain the in-plane temperature of the sample W in a desired temperature pattern.

  In particular, the thickness of the mounting plate 11 is preferably 0.3 mm or more and 2.0 mm or less. The reason is that if the thickness of the mounting plate 11 is less than 0.3 mm, the risk of discharge is increased due to the voltage applied to the internal electrode 13 for electrostatic adsorption. This is because W cannot be sufficiently adsorbed and fixed, and thus it is difficult to sufficiently heat the plate-like sample W.

The internal electrode 13 for electrostatic adsorption is used as an electrode for an electrostatic chuck for generating a charge and fixing a plate-like sample with an electrostatic adsorption force. Adjusted.
The internal electrode 13 for electrostatic adsorption is composed of an aluminum oxide-tantalum carbide (Al ₂ O ₃ —Ta ₄ C ₅ ) conductive composite sintered body, an aluminum oxide-tungsten (Al ₂ O ₃ —W) conductive composite sintered body. body, aluminum oxide - silicon carbide _{(Al 2} O 3 -SiC) conductive composite sintered body, an aluminum nitride - tungsten (AlN-W) conductive composite sintered body, an aluminum nitride - tantalum (AlN-Ta) conductive composite With sintered ceramics, conductive ceramics such as yttrium oxide-molybdenum (Y ₂ O ₃ -Mo) conductive composite sintered bodies, or refractory metals such as tungsten (W), tantalum (Ta), molybdenum (Mo) Is formed.

The thickness of the electrostatic attraction internal electrode 13 is not particularly limited, but is preferably 0.1 μm or more and 100 μm or less, and particularly preferably 5 μm or more and 20 μm or less. The reason is that if the thickness is less than 0.1 μm, sufficient conductivity cannot be ensured. On the other hand, if the thickness exceeds 100 μm, the electrostatic adsorption internal electrode 13, the mounting plate 11, and the support plate This is because, due to the difference in thermal expansion coefficient between the internal electrode 13 for electrostatic attraction and the mounting plate 11 and the support plate 12, cracks are likely to occur.
The electrostatic adsorption internal electrode 13 having such a thickness 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.

  The insulating material layer 14 surrounds the electrostatic adsorption internal electrode 13 to protect the electrostatic adsorption internal electrode 13 from corrosive gas and its plasma, and at the boundary between the mounting plate 11 and the support plate 12, that is, The outer peripheral region other than the internal electrode 13 for electrostatic attraction is joined and integrated, and is composed of the same composition or the main component of the same material as that of the mounting plate 11 and the support plate 12 and the same insulating material.

  The power feeding terminal 15 is a rod-shaped one provided to apply a DC voltage to the electrostatic adsorption internal electrode 13. The material of the power feeding terminal 15 is a conductive material having excellent heat resistance. Although not particularly limited, it is preferable that the coefficient of thermal expansion approximates the coefficient of thermal expansion of the electrostatic adsorption internal electrode 13 and the support plate 12, for example, the conductive material constituting the electrostatic adsorption internal electrode 13. Or metal materials such as tungsten (W), tantalum (Ta), molybdenum (Mo), niobium (Nb), and Kovar alloy are preferably used.

The power feeding terminal 15 is insulated from the temperature adjusting base portion 3 by an insulator 17 having an insulating property.
The power supply terminal 15 is joined and integrated with the support plate 12, and the mounting plate 11 and the support plate 12 are joined and integrated by the electrostatic adsorption internal electrode 13 and the insulating material layer 14. The chuck part 2 is configured.

The temperature adjusting base portion 3 is for adjusting the electrostatic chuck portion 2 to a desired temperature, and has a thick disk shape.
As this temperature adjustment base part 3, for example, a water-cooled base in which a flow path (not shown) for circulating water is formed is suitable.
The material constituting the temperature adjusting base 3 is not particularly limited as long as it is a metal excellent in thermal conductivity, conductivity, and workability, or a composite material containing these metals. For example, aluminum (Al) Aluminum alloy, copper (Cu), copper alloy, stainless steel (SUS) and the like are preferably used. It is preferable that at least the surface of the temperature adjusting base portion 3 exposed to the plasma is anodized or an insulating film such as alumina is formed.

The adhesive 4 is a sheet-like or film-like adhesive resin having the same pattern shape as the heater element 5 described later, which has heat resistance and insulation properties such as polyimide resin, silicone resin, and epoxy resin, and has a thickness of 5 μm to 5 μm. 100 micrometers is preferable, More preferably, they are 10 micrometers-50 micrometers. The in-plane thickness variation of the adhesive 4 is preferably within 10 μm.
Here, if the in-plane thickness variation of the adhesive 4 exceeds 10 μm, the in-plane spacing between the electrostatic chuck portion 2 and the heater element 5 exceeds 10 μm. Since the in-plane uniformity of the heat transmitted to the chuck portion 2 is reduced and the in-plane temperature on the mounting surface of the electrostatic chuck portion 2 becomes non-uniform, it is not preferable.

  The heater element 5 is disposed on the lower surface of the support plate 12 with an adhesive 4 interposed therebetween. For example, as shown in FIG. 2, two heaters independent from each other, that is, an inner heater formed in the center portion. 5a and an outer heater 5b formed annularly on the outer periphery of the inner heater 5a. Each of the connection positions 21 to the power supply terminals at both ends of the inner heater 5a and the outer heater 5b is respectively 1 is connected, and the power supply terminal 22 is insulated from the temperature adjusting base portion 3 by an insulator 23 having an insulating property.

Each of the inner heater 5a and the outer heater 5b has a pattern in which a narrow band-shaped metal material meanders is repeatedly arranged around the axis, and adjacent patterns are connected to each other. One continuous belt-like heater pattern is formed.
In the heater element 5, the in-plane temperature distribution of the plate-like sample W fixed to the mounting surface of the mounting plate 11 by electrostatic adsorption is controlled by independently controlling the inner heater 5a and the outer heater 5b. It is designed to control with high accuracy.

  The heater pattern of the heater element 5 may be constituted by two or more heater patterns independent from each other as described above, or may be constituted by one heater pattern. When the heater element 5 is composed of two or more heater patterns independent of each other like the outer heater 5b, the temperature of the plate-like sample W being processed can be freely controlled by individually controlling these mutually independent heater patterns. It is preferable because it can be controlled.

The heater element 5 has a constant thickness of 0.2 mm or less, preferably 0.1 mm or less, such as a non-magnetic metal thin plate, such as a titanium (Ti) thin plate, a tungsten (W) thin plate, a molybdenum (Mo) thin plate, or the like. Is formed by etching into a desired heater pattern by photolithography.
Here, the reason why the thickness of the heater element 5 is set to 0.2 mm or less is that when the thickness exceeds 0.2 mm, the pattern shape of the heater element 5 is reflected as the temperature distribution of the plate-like sample W. This is because it becomes difficult to maintain the in-plane temperature in a desired temperature pattern.

Further, when the heater element 5 is formed of a nonmagnetic metal, the heater element does not self-heat due to the high frequency even when the electrostatic chuck device 1 is used in a high frequency atmosphere, and therefore the in-plane temperature of the plate-like sample W is kept at a desired constant level. Since it becomes easy to maintain temperature or a fixed temperature pattern, it is preferable.
Further, when the heater element 5 is formed using a non-magnetic metal thin plate having a constant thickness, the thickness of the heater element 5 is constant over the entire heating surface, and the amount of heat generation is also constant over the entire heating surface. The temperature distribution on the two mounting surfaces can be made uniform.

  In the heater element 5, the inner heater 5a and the outer heater 5b are independently controlled, so that the heater pattern of the heater element 5 can be made difficult to be reflected in the plate-like sample W. Therefore, the in-plane temperature distribution of the plate-like sample W fixed to the placement surface of the placement plate 11 by electrostatic adsorption can be accurately controlled to a desired temperature pattern.

The adhesive 6 is for adhering the insulating member 7 to the upper surface of the temperature adjusting base 3, and like the adhesive 4, it is a sheet having heat resistance and insulating properties such as polyimide resin, silicone resin, and epoxy resin. Alternatively, it is a film-like adhesive resin, and the thickness is preferably 5 μm to 100 μm, more preferably 10 μm to 50 μm.
The in-plane thickness variation of the adhesive 6 is preferably within 10 μm.
Here, when the variation in the in-plane thickness of the adhesive 6 exceeds 10 μm, the distance between the temperature adjusting base 3 and the insulating member 7 exceeds 10 μm. As a result, the temperature adjusting base 3 In-plane uniformity of temperature control of the electrostatic chuck portion 2 is lowered, and the in-plane temperature on the mounting surface of the electrostatic chuck portion 2 becomes non-uniform, which is not preferable.

The insulating member 7 is a film-like or sheet-like resin having insulation properties and voltage resistance such as polyimide resin, silicone resin, epoxy resin, etc., and the variation in the thickness of the insulating member 7 is preferably within 10 μm.
Here, if the in-plane thickness variation of the insulating member 7 exceeds 10 μm, a difference in temperature distribution occurs depending on the thickness, and as a result, the temperature control by adjusting the thickness of the insulating member 7 is adversely affected. It is not preferable.

The thermal conductivity of the insulating member 7 is preferably 0.05 W / mk or more and 0.5 W / mk or less, more preferably 0.1 W / mk or more and 0.25 W / mk or less.
Here, if the thermal conductivity is less than 0.1 W / mk, it is difficult to transfer heat from the electrostatic chuck portion 2 to the temperature adjusting base portion via the insulating member 7 and the cooling rate is decreased. On the other hand, if the thermal conductivity exceeds 1 W / mk, heat transfer from the heater portion to the temperature adjusting base portion 3 through the insulating member 7 is increased, and the rate of temperature increase is not preferable.

  The organic adhesive layer 8 includes a heater element 5 bonded to the lower surface of the electrostatic chuck portion 2 via an adhesive 4 and an insulating member 7 bonded to the temperature adjusting base portion 3 via an adhesive 6. The organic adhesive layer 8 preferably has a thickness of 50 μm or more and 500 μm or less.

  Here, the reason why the thickness of the organic adhesive layer 8 is in the above range is that when the thickness of the organic adhesive layer 8 is less than 50 μm, the electrostatic chuck portion 2 and the temperature adjusting base portion 3 Although the thermal conductivity between them becomes good, the thermal stress relaxation becomes insufficient, and cracks and cracks are likely to occur. On the other hand, if the thickness of the organic adhesive layer 8 exceeds 500 μm, the electrostatic chuck portion This is because sufficient thermal conductivity between the temperature adjusting base 2 and the temperature adjusting base 3 cannot be ensured.

The organic adhesive layer 8 is formed of, for example, a cured body obtained by heat-curing a silicone resin composition or an acrylic resin.
The silicone resin composition is a resin excellent in heat resistance and elasticity, and is a silicon compound having a siloxane bond (Si—O—Si). This silicone resin composition can be represented, for example, by the chemical formula of the following formula (1) or 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。

Here, R is, H or an alkyl group _{(C n H 2n + 1 -} : n is an integer) is.

但し、Ｒは、Ｈまたはアルキル基（Ｃ_ｎＨ_２ｎ＋１−：ｎは整数）である。

Here, R is, H or an alkyl group _{(C n H 2n + 1 -} : n is an integer) is.

As such a silicone resin, a silicone resin having a thermosetting temperature of 70 ° C. to 140 ° C. is particularly preferable.
Here, when the thermosetting temperature is lower than 70 ° C., when joining the support plate 12 and the heater element 5 of the electrostatic chuck portion 2 with the temperature adjusting base portion 3 and the insulating member 7 facing each other, Curing starts in the joining process, and workability is inferior. On the other hand, when the thermosetting temperature exceeds 140 ° C., the difference in thermal expansion between the support plate 12 and the heater element 5 of the electrostatic chuck portion 2, the temperature adjusting base portion 3 and the insulating member 7 is large, and the electrostatic chuck portion 2. The stress between the support plate 12 and the heater element 5, the temperature adjusting base portion 3 and the insulating member 7 increases, and there is a possibility that peeling may occur between them.

  The silicone resin is preferably a resin having a Young's modulus after curing of 8 MPa or less. Here, when the Young's modulus after curing exceeds 8 MPa, the thermal expansion difference between the support plate 12 and the temperature-adjusting base portion 3 when the organic adhesive layer 8 is subjected to a temperature cycle of increasing and decreasing temperatures. Cannot be absorbed, and the durability of the organic adhesive layer 8 is lowered, which is not preferable.

The organic adhesive layer 8 has a filler made of an inorganic oxide, inorganic nitride, or inorganic oxynitride having an average particle diameter of 1 μm or more and 10 μm or less, for example, silicon oxide (AlN) particles on the surface of aluminum oxide (AlN) particles. it is preferred that the surface-coated aluminum nitride coating layer made of SiO ₂₎ was formed (AlN) particles are contained.
The surface-coated aluminum nitride (AlN) particles are mixed to improve the thermal conductivity of the silicone resin, and the heat transfer rate of the organic adhesive layer 8 is controlled by adjusting the mixing rate. be able to.

That is, by increasing the mixing rate of the surface-coated aluminum nitride (AlN) particles, the heat transfer rate of the organic adhesive constituting the organic adhesive layer 8 can be increased.
In addition, since a coating layer made of silicon oxide (SiO ₂ ) is formed on the surface of aluminum nitride (AlN) particles, it has superior water resistance compared to simple aluminum nitride (AlN) particles that are not surface-coated. have. Therefore, the durability of the organic adhesive layer 8 containing the silicone resin composition as a main component can be secured, and as a result, the durability of the electrostatic chuck device 1 can be dramatically improved.

Further, since the surface-coated aluminum nitride (AlN) particles are coated with a coating layer made of silicon oxide (SiO ₂ ) having excellent water resistance, the surface of the aluminum nitride (AlN) particles is aluminum nitride (AlN). ) Is not hydrolyzed by water in the atmosphere, the heat transfer rate of aluminum nitride (AlN) is not lowered, and the durability of the organic adhesive layer 8 is improved.
The surface-coated aluminum nitride (AlN) particles do not have a risk of becoming a contamination source for the plate-like sample W such as a semiconductor wafer, and can be said to be a preferable filler from this point.

  Since the surface-coated aluminum nitride (AlN) particles can obtain a strong bonded state by Si in the coating layer and the silicone-based resin composition, the stretchability of the organic adhesive layer 8 is improved. Is possible. Thereby, the thermal stress resulting from the difference between the thermal expansion coefficient of the support plate 12 of the electrostatic chuck part 2 and the thermal expansion coefficient of the temperature adjusting base part 3 can be alleviated. The base part 3 for use can be bonded firmly with high accuracy. Moreover, since the durability against the thermal cycle load during use is sufficient, the durability of the electrostatic chuck device 1 is improved.

The average particle diameter of the surface-coated aluminum nitride (AlN) particles is preferably 1 μm or more and 10 μm or less, more preferably 2 μm or more and 5 μm or less.
Here, when the average particle size of the surface-coated aluminum nitride (AlN) particles is less than 1 μm, the contact between the particles becomes insufficient, and as a result, the heat transfer rate may be lowered, and the particle size is small. If it is too much, workability such as handling is reduced, which is not preferable. On the other hand, if the average particle diameter exceeds 10 μm, the thickness of the adhesive layer tends to vary, which is not preferable.

  Further, the organic adhesive layer 8 may be formed of a thermosetting acrylic resin adhesive having a Young's modulus of 1 GPa or less and flexibility (Shore hardness of A100 or less). In this case, the filler may or may not be contained.

Next, a method for manufacturing the electrostatic chuck device 1 will be described.
First, the plate-shaped mounting plate 11 and the support plate 12 are produced from an aluminum oxide-silicon carbide (Al ₂ O ₃ —SiC) composite sintered body or an yttrium oxide (Y ₂ O ₃ ) sintered body. In this case, a mixed powder containing silicon carbide powder and aluminum oxide powder or yttrium oxide powder is formed into a desired shape, and then, for example, at a temperature of 1400 ° C. to 2000 ° C. in a non-oxidizing atmosphere, preferably an inert atmosphere. The mounting plate 11 and the support plate 12 can be obtained by baking for a predetermined time.

Next, a plurality of fixing holes for fitting and holding the power supply terminals 15 are formed in the support plate 12.
Next, the power supply terminal 15 is fabricated so as to have a size and shape that can be tightly fixed to the fixing hole of the support plate 12. As a method for producing the power supply terminal 15, for example, when the power supply terminal 15 is made of a conductive composite sintered body, a method of forming a conductive ceramic powder into a desired shape and pressurizing and firing can be cited. .

At this time, the conductive ceramic powder used for the power feeding terminal 15 is preferably a conductive ceramic powder made of the same material as the internal electrode 13 for electrostatic adsorption.
In addition, when the power supply terminal 15 is made of metal, a method of using a refractory metal and a metal working method such as a grinding method or powder metallurgy, or the like can be used.

Next, for electrostatic adsorption, a conductive material such as the conductive ceramic powder is dispersed in an organic solvent so as to come into contact with the power supply terminal 15 in a predetermined region on the surface of the support plate 12 in which the power supply terminal 15 is fitted. An internal electrode forming coating solution is applied and dried to form an electrostatic adsorption internal electrode forming layer.
As this coating method, it is desirable to use a screen printing method or the like because it is necessary to apply the film to a uniform thickness. Other methods include forming a thin film of the above-mentioned refractory metal by vapor deposition or sputtering, or arranging an electroconductive ceramic or refractory metal thin plate to provide an internal electrode for electrostatic adsorption. There is a method of forming a formation layer.

  Further, in order to improve insulation, corrosion resistance, and plasma resistance in a region other than the region where the internal electrode forming layer for electrostatic attraction is formed on the support plate 12, the same as the mounting plate 11 and the support plate 12. An insulating material layer including a powder material having the same composition or main component is formed. For example, the insulating material layer is formed by applying a coating solution in which an insulating material powder having the same composition or the same main component as the mounting plate 11 and the support plate 12 is dispersed in an organic solvent by screen printing or the like, and drying the coating. Can be formed.

Next, the mounting plate 11 is overlaid on the electrostatic adsorption internal electrode forming layer and the insulating material layer on the support plate 12, and these are then integrated by hot pressing under high temperature and high pressure. The atmosphere in this hot press is preferably a vacuum or an inert atmosphere such as Ar, He, N ₂ or the like. Moreover, the pressure in the case of uniaxial pressurization in a hot press is preferably 5 to 10 MPa, and the temperature is preferably 1400 ° C to 1850 ° C.

By this hot pressing, the internal electrode forming layer for electrostatic adsorption is fired to become the internal electrode 13 for electrostatic adsorption made of a conductive composite sintered body. At the same time, the support plate 12 and the mounting plate 11 are joined and integrated through the insulating material layer 14.
In addition, the power supply terminal 15 is refired by hot pressing under high temperature and high pressure, and is closely fixed to the fixing hole of the support plate 12.
Then, the upper and lower surfaces, outer periphery, gas holes, and the like of these joined bodies are machined to form an electrostatic chuck portion 2.

Next, a predetermined region on the surface (lower surface) of the support plate 12 of the electrostatic chuck portion 2 has heat resistance and insulation properties such as polyimide resin, silicone resin, epoxy resin, etc. and has the same pattern shape as the heater element 5. A sheet-like or film-like adhesive resin is pasted to obtain an adhesive 4.
This adhesive 4 is made by sticking an adhesive resin sheet or adhesive resin film having heat resistance and insulation properties such as polyimide resin, silicone resin, epoxy resin, etc. on the surface (lower surface) of the support plate 12, and this sheet or It can also be produced by forming the same pattern as the heater element 5 on the film.

Next, the adhesive 4 has a constant thickness of 0.2 mm or less, preferably 0.1 mm or less, such as a titanium (Ti) thin plate, a tungsten (W) thin plate, a molybdenum (Mo) thin plate, or the like. A nonmagnetic metal thin plate is attached, and the nonmagnetic metal thin plate is etched into a desired heater pattern by a photolithography method to obtain a heater element 5.
Thereby, the electrostatic chuck part with a heater element in which the heater element 5 having a desired heater pattern is formed on the surface (lower surface) of the support plate 12 via the adhesive 4 is obtained.

Next, a power supply terminal 22 having a predetermined size and shape is produced. The method for producing the power supply terminal 22 is similar to the method for producing the power supply terminal 15 described above. For example, when the power supply terminal 22 is a conductive composite sintered body, the conductive ceramic powder is formed into a desired shape. And press firing.
In addition, when the power feeding terminal 22 is made of metal, a method of using a refractory metal and a metal working method such as a grinding method or powder metallurgy, or the like can be used.

On the other hand, a metal material made of aluminum (Al), aluminum alloy, copper (Cu), copper alloy, stainless steel (SUS), etc. is machined, and water is circulated inside the metal material as necessary. Forming a path and the like, and further forming a fixing hole for fitting and holding the power supply terminal 15 and the insulator 17, and a fixing hole for fitting and holding the power supply terminal 22 and the insulator 23, and a temperature adjusting base portion 3.
It is preferable that at least the surface exposed to the plasma of the temperature adjusting base portion 3 is subjected to alumite treatment or an insulating film such as alumina is formed.

Next, the joint surface of the temperature adjusting base portion 3 with the electrostatic chuck portion 2 is degreased and washed using, for example, acetone, and a heat-resistant material such as polyimide resin, silicone resin, epoxy resin, or the like is placed at a predetermined position on the joint surface. A sheet-like or film-like adhesive resin having adhesiveness and insulating properties is pasted to obtain an adhesive 6.
Next, a film-like or sheet-like resin having insulating properties and voltage resistance such as a polyimide resin, a silicone resin, and an epoxy resin having the same planar shape as that of the adhesive material 6 is stuck on the adhesive material 6 and insulated. This is member 7.

Next, an adhesive made of, for example, a silicone-based resin composition is applied to a predetermined region on the temperature adjustment base portion 3 on which the adhesive 6 and the insulating member 7 are laminated. The amount of the adhesive applied is set within a predetermined range so that the electrostatic chuck portion 2 and the temperature adjusting base portion 3 can be joined and integrated with the spacer kept at a constant interval.
Examples of the method for applying the adhesive include manual application using a spatula and the like, as well as a bar coating method, a screen printing method, and the like. For this reason, it is preferable to use a screen printing method or the like.

After the application, the electrostatic chuck portion 2 and the temperature adjusting base portion 3 are superposed via an adhesive. At this time, the erected power supply terminal 15 and the insulator 17 and the power supply terminal 22 and the insulator 23 are inserted and fitted into a power supply terminal accommodation hole (not shown) drilled in the temperature adjusting base portion 3.
Subsequently, the electrostatic chuck part 2 and the temperature adjusting base part 3 are dropped until the distance between the electrostatic chuck part 2 and the temperature adjusting base part 3 reaches the thickness of the spacer, and the extruded excess adhesive is removed.

  As described above, the electrostatic chuck portion 2 and the temperature adjusting base portion 3 are joined and integrated through the adhesive 6, the insulating member 7, and the organic adhesive layer 8, and the electrostatic chuck device 1 of the present embodiment is obtained. Will be.

  The electrostatic chuck device 1 obtained in this way includes an electrostatic chuck portion 2 to which a heater element 5 is bonded via a sheet-like or film-like adhesive 4 and a temperature adjusting base portion 3. Since the adhesive is integrated through the system adhesive layer 8 and the sheet-like or film-like insulating member 7, the insulation between the electrostatic chuck portion 2 and the temperature adjusting base portion 3 can be maintained well. Therefore, the voltage resistance between the electrostatic chuck portion 2 and the temperature adjusting base portion 3 can be improved.

Further, since the heater element 5 is bonded to the electrostatic chuck portion 2 via the sheet-like or film-like adhesive 4, the uniformity of the in-plane temperature on the mounting surface of the electrostatic chuck portion 2 can be improved. The withstand voltage of the heater element 5 can be further improved.
Further, since the organic adhesive layer 8 is interposed between the electrostatic chuck portion 2 to which the heater element 5 is bonded and the temperature adjusting base portion 3, the organic adhesive layer 8 serves as the electrostatic chuck portion 2. By functioning as a buffer layer that relieves sudden expansion / contraction, it is possible to prevent cracks, chips, etc. in the electrostatic chuck portion 2, and thus improve the durability of the electrostatic chuck portion 2. Can do.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited by these Examples.

"Example 1"
(Production of electrostatic chuck device)
An electrostatic chuck portion 2 in which an internal electrode 13 for electrostatic attraction having a thickness of 20 μm was embedded was produced by a known method.
The mounting plate 11 of the electrostatic chuck portion 2 is an aluminum oxide-silicon carbide composite sintered body containing 8.5% by mass of silicon carbide, and has a disk shape with a diameter of 298 mm and a thickness of 0.5 mm. It was. Further, the electrostatic chucking surface of the mounting plate 11 is formed as a concavo-convex surface by forming a large number of projections 16 having a height of 40 μm, and the top surface of these projections 16 is used as a holding surface for the plate-like sample W. The cooling gas can be made to flow in a groove formed between the recess and the electrostatically adsorbed plate-like sample W.

Similarly to the mounting plate 11, the support plate 12 is an aluminum oxide-silicon carbide composite sintered body containing 8.5% by mass of silicon carbide, and has a disk shape with a diameter of 298 mm and a thickness of 2 mm.
By joining and integrating the mounting plate 11 and the support plate 12, the entire thickness of the electrostatic chuck portion 2 was 2.5 mm.

On the other hand, an aluminum temperature adjusting base 3 having a diameter of 350 mm and a height of 30 mm was produced by machining. A flow path (not shown) for circulating the refrigerant was formed inside the temperature adjusting base 3.
In addition, a square spacer having a width of 2000 μm, a length of 2000 μm, and a height of 200 μm was fabricated using an aluminum oxide sintered body.

Next, the surface (lower surface) of the support plate 12 of the electrostatic chuck unit 2 is degreased and washed with acetone, and a sheet adhesive made of an epoxy resin having a thickness of 20 μm is attached to a predetermined region of the surface. Adhesive 4 was obtained.
Next, a titanium (Ti) thin plate having a thickness of 100 μm was placed on the adhesive 4. Subsequently, the pressure was held at 150 ° C. in a vacuum, and the electrostatic chuck portion 2 and a titanium (Ti) thin plate were bonded and fixed.

Next, the titanium (Ti) thin plate was etched into the heater pattern shown in FIG. In addition, a power feeding terminal 22 made of titanium was erected on the heater element 5 using a welding method.
Thereby, the electrostatic chuck part with a heater element was obtained.

  Next, the bonding surface of the temperature adjusting base portion 3 to the electrostatic chuck portion 2 is degreased and washed with acetone, and a sheet made of an epoxy resin having a thickness of 20 μm as an adhesive 6 is provided at a predetermined position on the bonding surface. An adhesive was stuck, and then a polyimide film having a thickness of 50 μm was stuck as the insulating member 7 on the sheet adhesive.

Moreover, the aluminum nitride (AlN) powder is mixed with a silicone resin-aluminum nitride (AlN) powder so as to be 20 vol% with respect to the aluminum nitride (AlN) powder, and the mixture is subjected to stirring and defoaming treatment. A silicone resin composition was obtained.
The aluminum nitride powder used had an average particle size of 10 to 20 μm selected by a wet sieve.

Next, a silicone resin composition is applied by a screen printing method onto the temperature adjustment base portion on which the sheet adhesive and the polyimide film are laminated, and then the electrostatic chuck portion and the temperature adjustment base portion are bonded to the silicone resin. Overlaid through the composition.
Next, the distance between the heater element of the electrostatic chuck portion and the temperature adjusting base portion is lowered to the height of the square spacer, that is, 200 μm, and then held at 110 ° C. for 12 hours to obtain a silicone resin composition. The product was cured and the electrostatic chuck portion and the temperature adjusting base portion were joined together to produce the electrostatic chuck device of Example 1.

(Evaluation)
The electrostatic chuck apparatus was evaluated for (1) voltage resistance, (2) in-plane temperature control and temperature rise / fall characteristics of the silicon wafer, and (3) in-plane temperature control of the silicon wafer under pseudo-plasma heat input.

(1) Withstand voltage The voltage was increased from 1 kV to 1 kV stepwise between the temperature adjusting base 3 and the heater element 5, a voltage of 10 kV maximum was applied, and the leakage current at each voltage was measured. Here, three types of electrostatic chuck devices having a thickness of 100 μm, 200 μm, and 300 μm of the organic adhesive layer 8 between the temperature adjusting base portion 3 and the heater element 5 are manufactured, and each withstand voltage is evaluated. did.
As a result, the leakage current when a voltage of 10 kV was applied to the three types of electrostatic chuck devices was 0.1 μA or less, indicating extremely good voltage resistance.

(2) In-plane temperature control and heating / cooling characteristics of silicon wafer a. A silicon wafer having a diameter of 300 mm is electrostatically adsorbed on the mounting surface of the electrostatic chuck unit 2, and 20 ° C. cooling water is circulated through the flow path (not shown) of the temperature adjustment base unit 3, while the center temperature of the silicon wafer is increased. The outer heater 5b and the inner heater 5a of the heater element 5 were energized so that the temperature was 40 ° C., and the in-plane temperature distribution of the silicon wafer at this time was measured using a thermography TVS-200EX (manufactured by Avionics, Japan). The result is shown in FIG. In the figure, A shows the in-plane temperature distribution in the one-diameter direction of the silicon wafer, and B shows the in-plane temperature distribution in the diametric direction perpendicular to the one-diameter direction of the silicon wafer.

next,
b. The energization amount of the outer heater 5b of the heater element 5 is increased, and the temperature of the outer periphery of the silicon wafer is increased at a temperature increase rate of 3.6 ° C./second so that the temperature of the outer periphery of the silicon wafer becomes 60 ° C. The temperature distribution was measured using a thermography TVS-200EX (Nippon Avionics). The result is shown in FIG. In the figure, A shows the in-plane temperature distribution in the one-diameter direction of the silicon wafer, and B shows the in-plane temperature distribution in the diametric direction perpendicular to the one-diameter direction of the silicon wafer.

further,
c. The energization of the outer heater 5b of the heater element 5 is stopped, and the temperature is lowered at 4.0 ° C./second so that the temperature of the outer peripheral portion of the silicon wafer becomes 30 ° C. The in-plane temperature distribution of the silicon wafer at this time is It measured using thermography TVS-200EX (made by Nippon Avionics). The result is shown in FIG. In the figure, A shows the in-plane temperature distribution in the one-diameter direction of the silicon wafer, and B shows the in-plane temperature distribution in the diametric direction perpendicular to the one-diameter direction of the silicon wafer.

  According to the measurement results a to c above, it was found that the in-plane temperature of the silicon wafer was well controlled within a range of ± 20 ° C.

(3) In-plane temperature control of silicon wafer under pseudo plasma heat input The electrostatic chuck apparatus 1 was fixed in a vacuum chamber, and the in-plane temperature of the silicon wafer under pseudo plasma heat input was measured. Here, as pseudo-plasma heat input, heating is performed by an external heater disposed 40 mm above the mounting surface of the electrostatic chuck apparatus 1 and having a surface shape with a diameter of 300 mm and an outer peripheral portion that generates more heat than the inside. Using. A He gas having a pressure of 30 torr was passed through a groove formed between the silicon wafer and the electrostatic chucking surface of the electrostatic chuck portion 2.

  Here, first, a silicon wafer having a diameter of 300 mm is electrostatically adsorbed on the mounting surface of the electrostatic chuck unit 2, and 20 ° C. cooling water is circulated through a flow path (not shown) of the temperature adjustment base unit 3. The outer heater 5b and the inner heater 5a of the heater element 5 were energized so that the temperature of the entire silicon wafer was 40 ° C.

Then
d. The outer heater 5b was further energized while maintaining the above energized state. When the in-plane temperature of the silicon wafer at this time was measured with a thermocouple, the temperature at the center of the silicon wafer was 60 ° C., and the temperature at the outer periphery of the silicon wafer was 70 ° C.
Then
e. While the energization of the inner heater 5a and the outer heater 5b of the heater element 5 was maintained, the energization amount of the outer heater 5b of the heater element 5 was lowered. When the in-plane temperature of the silicon wafer at this time was measured with a thermocouple, the temperature was constant at 60 ° C. throughout the silicon wafer.

  According to the measurement results of de above, it was found that the in-plane temperature of the silicon wafer was well controlled within the range of 10 ° C. even under pseudo plasma heat input.

"Example 2"
(Production of electrostatic chuck device)
Except that the mounting plate 11 and the support plate 12 of the electrostatic chuck portion 2 are made of yttrium oxide sintered body and the electrostatic adsorption internal electrode 13 is made of yttrium oxide-molybdenum conductive composite sintered body, the same as in Example 1. Thus, the electrostatic chuck device of Example 2 was produced.

(Evaluation)
The electrostatic chuck device of Example 2 was evaluated according to Example 1.
As a result, as for (1) withstand voltage, the leakage current when a voltage of 10 kV or 4 kV was applied was 0.1 μA or less, indicating a very good withstand voltage. (2) It was found that the in-plane temperature control and temperature rise / fall characteristics of the silicon wafer were well controlled within the range of ± 20 ° C. of the in-plane temperature of the silicon wafer. It was also found that (3) the in-plane temperature control of the silicon wafer under pseudo-plasma heat input was well controlled within the range of 10 ° C. of the silicon wafer.

"Comparative Example 1"
(Production of electrostatic chuck device)
An adhesive made of a viscous liquid epoxy resin is applied to a predetermined region of the surface (lower surface) of the support plate 12 of the electrostatic chuck portion 2 to form an adhesive layer, and a thickness is formed on the adhesive layer. The electrostatic chuck device of Comparative Example 1 was produced in the same manner as Example 1 except that a 100 μm titanium (Ti) thin plate was adhered and fixed.

(Evaluation)
The electrostatic chuck device of Comparative Example 1 was evaluated according to Example 1.
As a result, regarding (1) withstand voltage, the leakage current when applying a voltage of 10 kV or 4 kV was 0.5 μA or less, indicating extremely good withstand voltage. In the in-plane temperature control and the temperature rise / fall characteristics, it was found that the in-plane temperature of the silicon wafer was in the range of ± 5.0 ° C., and the in-plane temperature uniformity was reduced. Also, (3) in the in-plane temperature control of the silicon wafer under pseudo plasma heat input, the in-plane temperature of the silicon wafer is in the range of ± 5.0 ° C., and the in-plane temperature uniformity is reduced. I understood that.

"Comparative Example 2"
(Production of electrostatic chuck device)
The electrostatic chuck device of Comparative Example 2 according to Example 1 except that the sheet adhesive and the polyimide film were not sequentially attached onto the joint surface of the temperature adjusting base 3 with the electrostatic chuck 2. Was made.

(Evaluation)
The electrostatic chuck device of Comparative Example 2 was evaluated according to Example 1.
As a result, regarding (1) withstand voltage, when the thickness of the organic adhesive layer 8 between the temperature adjusting base portion 3 and the heater element 5 is 100 μm, discharge occurs at 2.6 kV to 7 kV, and the thickness is At 200 μm, discharge occurred at 10 kV, and at 300 μm, no discharge occurred at 10 kV. As a result, when the thickness of the organic adhesive layer 8 is 300 μm, the voltage resistance is extremely good. However, when the thickness is 200 μm or less, discharge occurs at a voltage of 10 kV or less, and the voltage resistance is lowered. It was.

  On the other hand, (2) In the in-plane temperature control and temperature rise / fall characteristics of the silicon wafer, the in-plane temperature of the silicon wafer is well controlled within a range of ± 20 ° C., and the in-plane temperature uniformity is improved. I understood. Also, (3) in-plane temperature control of silicon wafers under pseudo plasma heat input, the in-plane temperature of silicon wafers is well controlled within the range of ± 10 ° C, improving the in-plane temperature uniformity. I found out.

DESCRIPTION OF SYMBOLS 1 Electrostatic chuck apparatus 2 Electrostatic chuck part 3 Temperature adjustment base part 4 Adhesive material 5 Heater element 5a Inner heater 5b Outer heater 6 Adhesive material 7 Insulating member 8 Organic adhesive layer 11 Mounting plate 12 Support plate 13 Electrostatic Internal electrode for adsorption 14 Insulating material layer 15 Terminal for feeding 16 Protrusion 17 Insulator 21 Connection position with terminal for feeding 22 Terminal for feeding 23 Insulator W Plate-like sample

Claims (7)

An electrostatic chuck portion having a main surface as a mounting surface on which a plate-like sample is placed and an internal electrode for electrostatic attraction is built in; a temperature adjustment base portion for adjusting the electrostatic chuck portion to a desired temperature; With
A heating member is bonded to the main surface opposite to the placement surface of the electrostatic chuck portion via an adhesive,
The whole or part of the surface of the temperature adjusting base portion on the electrostatic chuck portion side is covered with a sheet-like or film-like insulating material,
The electrostatic chuck portion to which these heating members are bonded and the temperature adjusting base portion covered with a sheet-like or film-like insulating material are formed by insulating organic adhesive layers formed by curing a liquid adhesive. Are bonded and integrated through
The heating member is a heater element composed of two or more heater patterns independent of each other,
The adhesive is formed in the same pattern that overlaps the heater element in plan view,
The unevenness formed by laminating the heater element and the adhesive is embedded in the organic adhesive layer.   The electrostatic chuck apparatus according to claim 1, wherein the organic adhesive layer has a Young's modulus of 1 GPa or less.   The electrostatic chuck apparatus according to claim 1, wherein the adhesive is a silicone or acrylic adhesive having a Young's modulus after curing of 8 MPa or less. Said sheet-shaped or film-shaped insulating material is a sheet-like or electrostatic film-like according to any one of claims 1, characterized in that it is bonded to the temperature-controlling base portion by an adhesive 3 Chuck device. The variation in the thickness of the adhesive material, the electrostatic chucking device of any one of claims 1 to 4, wherein the at 10μm or less. The electrostatic chuck portion includes a mounting plate having one main surface as the mounting surface, a support plate integrated with the mounting plate and supporting the mounting plate, and the mounting plate and the support plate. An internal electrode for electrostatic attraction provided therebetween,
The mounting plate is aluminum oxide - electrostatic chucking device according to any one of claims 1, characterized in that it consists of silicon carbide composite sintered body, or yttrium oxide sintered body 5.   It is a manufacturing method of the electrostatic chuck device according to any one of claims 1 to 6,
  A method of manufacturing an electrostatic chuck device, comprising: a step of etching a non-magnetic metal thin plate by a photolithography method to obtain the heating member.

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