JP5504924B2 - 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. Even in various processes such as film deposition by phase growth (CVD), etching such as plasma etching, and exposure, the in-plane temperature distribution in the plate-like sample is small, and adjustment of temperature changes with time due to plasma application is possible. The present invention relates to an electrostatic chuck apparatus capable of adjusting a temperature in a wide temperature range and capable of local temperature control.

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 increase in the surface temperature, a cooling medium such as water is circulated through the temperature adjustment base of the electrostatic chuck device to cool the wafer from the lower side. Due to variations in the heat input in the wafer surface, a temperature distribution is generated in the wafer surface. 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.
As a method for adjusting the in-plane temperature distribution of the wafer, conventionally, an electrostatic chuck device that adjusts the gas pressure in the surface by flowing a gas such as helium between the wafer and the adsorption surface of the electrostatic chuck. Is known (Patent Document 1).
There has also been proposed an electrostatic chuck device capable of adjusting the in-plane temperature distribution of the wafer by adjusting the contact area between the wafer and the chucking surface of the electrostatic chuck.

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 also been proposed (Patent Document 2). 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, the heater is baked into the ceramic as the electrostatic chuck, or the back side of the adsorption surface of the electrostatic chuck, that is, the back surface of the ceramic plate body by screen printing. There is a method in which a material is applied in a predetermined pattern and cured by heating.

Japanese Patent Laid-Open No. 9-134951 JP 2008-300491 A

By the way, in the electrostatic chuck device for adjusting the in-plane temperature distribution of the wafer using the above-described conventional gas such as helium or the electrostatic chuck device for adjusting the contact area between the wafer and the chucking surface of the electrostatic chuck, There was a problem that it was difficult to perform local temperature control.
In addition, in conventional electrostatic chuck devices with a heater function, cracks may occur in the electrostatic chuck, the temperature adjustment base, and the heater itself due to rapid heating and lowering of the heater. There was a problem that the property was insufficient.

  In addition, the installation of a heater necessitates a power source for supplying power to the heater, a temperature controller, and a filter that cuts high frequencies when plasma is generated, resulting in a problem that the apparatus is complicated and expensive.

  The present invention has been made in view of the above circumstances, and when applied to a processing apparatus such as a plasma etching apparatus, causes a local temperature distribution in the plane of a plate-like sample such as a silicon wafer. Accordingly, an object of the present invention is to provide an electrostatic chuck device capable of performing local temperature control of a plate-like sample such as a silicon wafer accompanying plasma application.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors provided an organic film having an insulating property on the entire surface or a part between the electrostatic chuck portion and the temperature adjusting base portion, and this organic film. If the temperature distribution on the wafer mounting surface is adjusted by adjusting the heat transfer between the electrostatic chuck portion and the temperature adjusting base portion by adjusting the position and thickness of the wafer, the silicon wafer It is possible to generate a local temperature distribution in the surface of a plate-like sample such as silicon wafers, and to adjust the plate-like sample such as a silicon wafer in a wide temperature range even without in-plane adjustment of the helium gas pressure or heater function. In addition, the inventors have found that local temperature control of a plate-like sample can be performed, and have completed the present invention.

That is, the electrostatic chuck device 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 placed and an internal electrode for electrostatic adsorption is built in, and the electrostatic chuck portion is desired. A temperature adjusting base portion that adjusts to the temperature of the substrate, and an insulating organic film provided on the entire surface or a part between the electrostatic chuck portion and the temperature adjusting base portion, and a position where the organic film is provided And adjusting the thickness in-plane to adjust the temperature distribution on the mounting surface , and the organic film is bonded to one main surface of the temperature-adjusting base portion via a first adhesive layer. And is bonded to the other main surface of the electrostatic chuck portion via a second adhesive layer, and the thermal conductivity of the first adhesive layer and the second adhesive layer is determined by the organic film. wherein the more the thermal conductivity is larger To.

  In this electrostatic chuck device, an organic film having an insulating property is provided on the entire surface or a part between the electrostatic chuck portion and the temperature adjusting base portion, and the position and thickness of the organic film are adjusted in-plane. By adjusting the temperature distribution on the mounting surface of the electrostatic chuck portion, heat transfer in the direction perpendicular to the mounting surface of the electrostatic chuck portion is reduced at a portion where the thickness of the organic film is thick. When the temperature of the part is adjusted by the temperature adjusting base part, the temperature of the mounting surface is higher than the part where the thickness of the organic film is thin. Thereby, it becomes possible to control the heat transfer between the electrostatic chuck portion and the temperature adjusting base portion by the position and thickness of the organic film. Therefore, it is possible to control the temperature distribution on the mounting surface of the electrostatic chuck portion by adjusting the position and thickness of the organic film in the plane.

Further, by making the thermal conductivity of the first adhesive layer and the second adhesive layer larger than the thermal conductivity of the organic film, the organic film, the first adhesive layer, and the second adhesive layer. The total heat transfer including the heat transfer is easily controlled by the thermal conductivity of the organic film, and thus the heat transfer between the electrostatic chuck and the temperature adjusting base is adjusted to the thickness of the organic film. It becomes possible to control easily. Therefore, it is possible to easily control the temperature distribution on the mounting surface of the electrostatic chuck portion by adjusting the thickness of the organic film in the plane.

  In the electrostatic chuck device of the present invention, the organic film is formed by changing the thickness of a desired region in the surface or laminating one or more organic films having a second insulating property in the desired region in the surface. It is characterized by becoming.

  In this electrostatic chuck device, the thickness of a desired region in the surface of the organic film is changed, or one or more organic films having a second insulating property are laminated in the desired region in the surface of the organic film. This makes it possible to easily change the thickness of a desired region in the plane of the organic film. Therefore, the temperature distribution on the mounting surface of the electrostatic chuck portion can be easily changed by changing the thickness of a desired region in the surface of the organic film.

In the electrostatic chuck device of the present invention, the first adhesive layer is a sheet-like or film-like adhesive.
In this electrostatic chuck device, since the first adhesive layer is a sheet or film adhesive, the thickness of the first adhesive layer can be accurately and easily controlled. It becomes possible to control the heat transfer between the electric chuck portion and the temperature adjusting base portion more accurately and easily. Therefore, it becomes possible to control the temperature distribution on the mounting surface of the electrostatic chuck portion more accurately and easily.

In the electrostatic chuck device of the present invention, the thickness of the electrostatic chuck portion is 0.7 mm or more and 3.0 mm or less.
In this electrostatic chuck apparatus, by setting the thickness of the electrostatic chuck portion to 0.7 mm or more and 3.0 mm or less, sufficient strength is given to the electrostatic chuck portion, and the heat capacity of the electrostatic chuck portion itself is increased. The plate-shaped sample to be mounted is excellent in thermal responsiveness, and it is possible to suppress the heat transfer in the lateral direction of the electrostatic chuck, and the desired temperature distribution can be obtained in the plate-shaped sample such as a silicon wafer. To get.

  According to the electrostatic chuck device of the present invention, an organic film having an insulating property is provided on the entire surface or a part between the electrostatic chuck portion and the temperature adjusting base portion, and the position and thickness of the organic film are set in the plane. By adjusting the temperature distribution on the mounting surface of the electrostatic chuck portion, the heat transfer between the electrostatic chuck portion and the temperature adjusting base portion can be controlled by the position and thickness of the organic film. it can. Therefore, the temperature distribution on the mounting surface of the electrostatic chuck portion can be controlled, the in-plane temperature distribution of the plate sample placed on the mounting surface can be reduced, and the temperature in a wide temperature range can be reduced. Adjustments can be made.

  Moreover, if the thickness of the desired area | region in the surface of an organic film is changed, or suppose that the organic film which has 2nd insulation was laminated | stacked on the desired area | region in the surface of this organic film. The thickness of the desired region in the plane of the organic film can be easily changed. Therefore, the temperature distribution on the mounting surface of the electrostatic chuck portion can be easily changed.

Further, if the first adhesive layer is a sheet-like or film-like adhesive, the heat transfer between the electrostatic chuck portion and the temperature adjusting base portion can be controlled more accurately and easily. . Therefore, the temperature distribution on the mounting surface of the electrostatic chuck portion can be controlled with higher accuracy and ease.
Moreover, if the thickness of the electrostatic chuck portion is 0.7 mm or more and 3.0 mm or less, sufficient strength can be imparted to the electrostatic chuck portion, its heat capacity can be reduced, and the electrostatic chuck portion can be placed. The thermal responsiveness of the plate sample can be improved, and the heat transfer in the lateral direction of the electrostatic chuck can be suppressed, and a desired temperature distribution can be obtained in the plate sample such as a silicon wafer. it can.

It is sectional drawing which shows the electrostatic chuck apparatus of one Embodiment of this invention. It is sectional drawing which shows the modification of the electrostatic chuck apparatus of one Embodiment of this invention.

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 disc-shaped temperature adjusting base portion 3 having a thickness to be adjusted to a temperature, and an insulating organic film 4 having heat resistance provided between the electrostatic chuck portion 2 and the temperature adjusting base portion 3; A sheet adhesive (first adhesive layer) 5 for bonding the insulating organic film 4 to the temperature-adjusting base portion 3 and the insulating organic film 4 are bonded to the electrostatic chuck portion 2 (second). It is mainly composed of the adhesive layer 6.

  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). It consists of an insulating ceramic sintered body having mechanical strength such as an O ₃ ) sintered body and an aluminum nitride (AlN) sintered body and having durability against a corrosive gas and its plasma.
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 and the support plate 12, 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 it exceeds, the heat transfer in the lateral direction of the electrostatic chuck portion 2 increases, a predetermined in-plane temperature distribution cannot be obtained, and the heat response is deteriorated by increasing the heat capacity.

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 It is made of conductive ceramics such as a sintered body, or a refractory metal such as tungsten (W), tantalum (Ta), molybdenum (Mo).

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 mounting plate 11 and the support plate 12 and the electrostatic adsorption internal electrode 13 are not secured. This is because cracks are likely to occur at the bonding interface between the mounting plate 11 and the support plate 12 due to the difference in thermal expansion coefficient between the mounting plate 11 and the supporting plate 12.
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 is a thick disk-shaped member made of metal and / or ceramics. 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 insulating organic film 4 is preferably a film-like resin having heat resistance and insulating properties, such as polyimide resin, silicone resin, and epoxy resin.
The in-plane thickness variation of the insulating organic film 4 is preferably within 10 μm.
Here, if the in-plane thickness variation of the insulating organic film 4 is 10 μm or more, a difference in temperature distribution occurs depending on the thickness, and as a result, temperature control by adjusting the thickness of the insulating organic film 4 is achieved. Since it has a bad influence, it is not preferable.

  In this insulating organic film 4, the thickness of the peripheral part 4a which is a desired area | region in the surface is set so that it may become thicker than the thickness of the center part 4b. For example, the thickness of the peripheral portion 4a is set to be 1.5 to 3 times the thickness of the central portion 4b.

The thermal conductivity of the insulating organic film 4 is preferably 0.05 W / mk or more and 0.3 W / mk or less, more preferably 0.1 W / mk or more and 0.2 W / mk or less.
Here, when the thermal conductivity is larger than 0.3 W / mk, the difference in thermal conductivity with the second adhesive layer is reduced, and it is difficult to make an in-plane temperature difference, which is not preferable. When the thermal conductivity is smaller than 0.05 W / mk, it becomes difficult to transfer heat from the electrostatic chuck portion 2 to the temperature adjustment base portion 3, and as a result, the electrostatic chuck portion 2 and the temperature adjustment base portion. 3 is not preferable because the heat transfer to and from 3 is controlled, the cooling characteristics are deteriorated, and the temperature control within the wafer surface becomes difficult.

  In this insulating organic film 4, the peripheral edge 4a is made thicker than the central part 4b, so that the heat transfer in the vertical direction is smaller in the peripheral part 4a than in the central part 4b. When the temperature is adjusted by the temperature adjusting base portion 3, the temperature at the peripheral portion of the placement surface is higher than the temperature at the center portion. Thereby, the heat transfer between the electrostatic chuck part 2 and the temperature adjusting base part 3 can be controlled by the difference between the thickness of the peripheral edge 4a and the thickness of the central part 4b of the insulating organic film 4. It becomes. Therefore, the temperature distribution on the mounting surface of the electrostatic chuck unit 2 can be controlled.

  FIG. 2 is a cross-sectional view showing a modified example of the electrostatic chuck device of the present embodiment. The electrostatic chuck device 21 has an in-plane thickness of an insulating organic film 22 having a uniform in-plane thickness and heat resistance. The difference from the electrostatic chuck device 1 is that the insulating organic film laminate 24 is formed by laminating the (second) heat-resistant insulating organic film 23 on the peripheral portion 22a which is a desired region. The other points are the same as those of the electrostatic chuck device 1.

The insulating organic film 23 is not necessarily made of the same material as that of the insulating organic film 22, but is preferably made of the same material as that of the insulating organic film 22 in view of the adhesive strength when the laminate is formed. .
The thickness of the insulating organic film 23 is set to be 0.5 to 3 times the thickness of the insulating organic film 22.

  Also in this insulating organic film laminate 24, heat transfer between the electrostatic chuck portion 2 and the temperature adjusting base portion 3 is performed by the thickness of the insulating organic film 22 and the total thickness of the insulating organic films 22 and 23. It becomes possible to control by the difference between Therefore, the temperature distribution on the mounting surface of the electrostatic chuck unit 2 can be controlled.

The sheet adhesive 5 is a sheet-like (or film-like) adhesive that fixes the insulating organic film 4 to the temperature adjusting base 3, and the material thereof is silicone that is a material having heat resistance and insulation. An adhesive made of resin, epoxy resin, polyimide resin or the like is preferable.
In particular, an adhesive containing silicon resin as a component has heat resistance up to 200 ° C., and has a larger elongation than an adhesive containing epoxy resin or polyimide resin as a component. The stress with the base portion 3 can be relaxed, and heat transfer is high, which is preferable.

The adhesive layer 6 is for fixing the insulating organic film 4 to the electrostatic chuck portion 2, and the material is an adhesive made of a heat-resistant and insulating material such as silicone resin, epoxy resin, polyimide resin, or the like. An adhesive made of an agent or a composite resin obtained by adding a heat conductive filler such as insulating aluminum nitride (AlN) or aluminum oxide (Al ₂ O ₃ ) to these resins is preferable.
In particular, an adhesive containing a silicone resin as a component has a heat resistance up to 200 ° C., and has a large elongation compared to an adhesive containing an epoxy resin or a polyimide resin, which are other heat-resistant adhesives. The stress between the electric chuck portion 2 and the temperature adjusting base portion 3 can be relaxed, and the thermal conductivity is high, which is preferable.

The thermal conductivity of each of the sheet adhesive 5 and the adhesive layer 6 needs to be larger than the thermal conductivity of the insulating organic film 4, and is preferably 0.1 W / mk or more and 1 W / mk or less, more preferably. Is 0.2 W / mk or more and 0.5 W / mk or less.
Here, if the thermal conductivity of each of the sheet adhesive 5 and the adhesive layer 6 is lower than 0.1 W / mK, the temperature adjustment efficiency from the electrostatic chuck portion 2 to the temperature adjustment base portion 3 is poor, and static The heat conduction in the part from the electric chuck part 2 via the sheet adhesive 5 and the adhesive layer 6 to the temperature adjusting base part 3 is reduced, and the temperature of the electrostatic chuck part 2 and the plate-like sample is not easily lowered. It is not preferable.

  On the other hand, when the thermal conductivity of each of the sheet adhesive 5 and the adhesive layer 6 exceeds 1 W / mK, the temperature adjustment efficiency between the electrostatic chuck portion 2 and the temperature adjustment base portion 3 becomes too high, The heat conduction in the portion from the electrostatic chuck portion 2 via the sheet adhesive 5 and the adhesive layer 6 to the temperature adjustment base portion 3 increases, and most of the heat generated by plasma irradiation or the like is the temperature adjustment base portion. 3 is not preferable because the temperature of the plate-like sample is hardly increased.

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. In this case, a mixed powder containing silicon carbide powder and aluminum oxide powder is formed into a desired shape, and then fired at a temperature of 1600 ° C. to 2000 ° C. in a non-oxidizing atmosphere, preferably an inert atmosphere for a predetermined time. By doing so, the mounting plate 11 and the support plate 12 can be obtained.

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, an organic solvent containing terpinol and ethyl cellulose as a conductive material such as the conductive ceramic powder 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. The coating solution for forming an internal electrode for electrostatic adsorption dispersed in is applied and dried to form an internal electrode forming layer for electrostatic adsorption.
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 liquid 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 containing terpinol, ethyl cellulose, or the like in the predetermined area. It can be formed by applying by printing or the like and drying.

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. The pressure is preferably 5 to 10 MPa, and the temperature is preferably 1600 ° 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.

On the other hand, the joint surface of the temperature adjusting base portion 3 with the electrostatic chuck portion 2 is degreased and cleaned using, for example, acetone, and the sheet adhesive 5 and the insulating organic film 4 are sequentially placed at predetermined positions on the joint surface. Overlapping.
An insulating organic film laminate 24 is used in place of the insulating organic film 4, and the sheet adhesive 5 and the insulating organic film laminate are disposed at predetermined positions on the joint surface of the temperature adjusting base portion 3 with the electrostatic chuck portion 2. The body 24 may be sequentially overlapped.

Next, an adhesive made of a silicone resin, an epoxy resin, a polyimide resin, or the like for forming the adhesive layer 6 is applied on the temperature adjusting base portion 3 on which the sheet adhesive 5 and the insulating organic film 4 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.
As a method for applying the adhesive, a bar coating method, a screen printing method, or the like can be used in addition to manual application using a spatula 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 power supply terminal 15 erected is inserted 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.
It is preferable that the dropping temperature is a temperature at which the fluidity of the adhesive is most obtained. In the process of dropping, the adhesive is cured to form an adhesive layer 6.

As described above, the electrostatic chuck portion 2 and the temperature adjusting base portion 3 are joined and integrated through the sheet adhesive material 5, the insulating organic film 4, and the adhesive layer 6, and the electrostatic chuck device 1 of this embodiment is integrated. Will be obtained.
Further, if the sheet adhesive 5 and the insulating organic film laminate 24 are sequentially laminated at predetermined positions on the joint surface of the temperature adjusting base 3 with the electrostatic chuck 2, the electrostatic chuck device 21 is can get.

  The electrostatic chuck devices 1 and 21 thus obtained can transfer heat between the electrostatic chuck portion 2 and the temperature adjusting base portion 3 to the thickness of the insulating organic film 4 or the insulating organic film laminate 24. Can be controlled. Therefore, the temperature distribution on the mounting surface of the electrostatic chuck unit 2 can be controlled, and the in-plane temperature distribution of the plate-like sample W mounted on the mounting surface can be reduced. As a result, the plasma It is possible to adjust the temperature change over time due to application or the like, or to adjust the temperature in a wide temperature range.

  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 in which an internal electrode for electrostatic adsorption having a thickness of 20 μm was embedded was manufactured by a known method.
The mounting plate of the electrostatic chuck portion 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 298 mm and a thickness of 0.5 mm. In addition, the electrostatic chucking surface of the mounting plate is formed as a concavo-convex surface by forming a large number of protrusions having a height of 30 μm, and the top surface of these protrusions is used as a holding surface for the plate-like sample, A cooling gas can be made to flow in a groove formed between the electroadsorbed plate-like sample.

The support plate was also an aluminum oxide-silicon carbide composite sintered body containing 8% by mass of silicon carbide, similar to the mounting plate, and had a disk shape with a diameter of 298 mm and a thickness of 1.0 mm.
By joining and integrating the mounting plate and the support plate, the overall thickness of the electrostatic chuck portion was 1.5 mm.

On the other hand, an aluminum temperature adjusting base portion having a diameter of 330 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 adjustment base.
Next, the bonding surface of the temperature adjusting base portion with the electrostatic chuck portion is degreased and washed with acetone, and a sheet adhesive having a diameter of 200 mm and a thickness of 20 μm made of an epoxy resin is formed at a predetermined position on the bonding surface, Insulating organic films made of polyimide resin having a diameter of 200 mm and a thickness of 50 μm were sequentially stacked.

Next, a silicone resin adhesive is applied to a thickness of 300 μm by a screen printing method on the temperature adjustment base portion on which the sheet adhesive and the insulating organic film are laminated, and then the electrostatic chuck portion and the temperature adjustment are performed. The base for use was superposed via an adhesive.
Subsequently, it dropped until the space | interval of an electrostatic chuck part and the base part for temperature control became 200 micrometers.
Subsequently, it hold | maintained at 120 degreeC in air | atmosphere for 5 hours, the silicone resin adhesive was hardened, the electrostatic chuck part and the base part for temperature control were joined, and the electrostatic chuck apparatus of Example 1 was produced.

(Evaluation)
A coolant (20 ° C.) is caused to flow at a flow rate of 30 L / min through the flow path of the temperature adjustment base portion of the electrostatic chuck device, and a silicon wafer for temperature measurement is placed on the placement plate. The wafer surface was heated by a heater installed on the upper surface of the wafer so that the heat flow rate on the wafer surface was 2.0 W / m ^2, and the surface temperature of the wafer was measured.

  According to this heating evaluation result, it was found that the temperature at the center of the wafer was 50 ° C. and the temperature at the outer periphery was 40 ° C. Therefore, the temperature distribution on the mounting surface of the electrostatic chuck portion could be controlled.

"Example 2"
An electrostatic chuck device of Example 2 was produced in accordance with Example 1 except that an adhesive sheet having the same thickness as that of the insulating organic film was adhered onto the insulating organic film to form a two-layer structure.
The electrostatic chuck device of Example 2 was evaluated according to Example 1.

  According to this heating evaluation result, it was found that the temperature of the central portion of the wafer was 60 ° C. and the temperature of the outer peripheral portion was 40 ° C. Accordingly, it has been found that the temperature distribution on the mounting surface of the electrostatic chuck portion can be controlled, and the in-plane temperature distribution of the silicon wafer mounted on the mounting surface can be adjusted.

"Comparative example"
(Production of electrostatic chuck device)
In accordance with Example 1, an electrostatic chuck device of a comparative example was produced.
However, a silicone resin adhesive is applied directly on the temperature adjustment base portion by screen printing so as to have a thickness of 300 μm, and then the electrostatic chuck portion and the temperature adjustment base portion are overlapped via the adhesive. Combined.

(Evaluation)
The electrostatic chuck device of the comparative example was evaluated according to Example 1.
According to this heating evaluation result, it was found that the temperature distribution in the wafer surface was constant. This electrostatic chuck device has a larger in-plane temperature distribution of the silicon wafer mounted on the mounting surface than the electrostatic chuck device of the embodiment, and can adjust the temperature change over time caused by plasma application or the like. The temperature could not be adjusted over a wide temperature range.

DESCRIPTION OF SYMBOLS 1 Electrostatic chuck apparatus 2 Electrostatic chuck part 3 Base part for temperature adjustment 4 Insulating organic film 4a Peripheral part 4b Center part 5 Sheet adhesive material (1st adhesive layer)
6 (Second) Adhesive Layer 11 Mounting Plate 12 Support Plate 13 Electrostatic Suction Internal Electrode 14 Insulating Material Layer 15 Power Feeding Terminal 16 Protrusion 17 Insulator 21 Electrostatic Chuck Device 22 Insulating Organic Film 22a Peripheral 22b Central part 23 Insulating organic film 24 Insulating organic film laminated body W Plate sample

Claims (4)

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; And an insulating organic film provided on the entire surface or a part between the electrostatic chuck portion and the temperature adjusting base portion, and adjusting the position and thickness of the organic film in-plane Adjust the temperature distribution on the mounting surface ,
The organic film is bonded to one main surface of the temperature adjusting base portion via a first adhesive layer, and to the other main surface of the electrostatic chuck portion via a second adhesive layer. Glued,
The electrostatic chuck apparatus, wherein the first adhesive layer and the second adhesive layer have a thermal conductivity greater than that of the organic film . The organic film, change the thickness of the desired area in the plane, or, characterized in that formed by laminating an organic film having a second insulating a desired region in the plane of one or more layers wherein Item 2. The electrostatic chuck device according to Item 1 . The electrostatic chuck device according to claim 1, wherein the first adhesive layer is a sheet-like or film-like adhesive. The electrostatic chuck apparatus according to claim 1, wherein the electrostatic chuck portion has a thickness of 0.7 mm or more and 3.0 mm or less.

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