JPH11323549A - Substrate holder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the deformation, by thermal distortion, of a substrate holder equipped with heating and cooling mechanisms used for production or inspection apparatuses for semiconductor devices, FPD devices, etc., with a simple construction. SOLUTION: Material having a relatively small coefft. of thermal expansion is used for a heating unit 1 contg. heating mechanisms and material having the coefft. of thermal expansion larger than the coefft. of thermal expansion of the heating unit is used for a cooling unit (2) contg. cooling mechanisms. The thickness, etc., of both are regulated, by which the thermal distortion may be reduced and the deformation suppressed even if a temp. gradient occurs across both units of the substrate holder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate holding apparatus capable of holding a substrate and heating and cooling the held substrate in a manufacturing apparatus or an inspection apparatus for a semiconductor device or a flat panel display device.

[0002]

2. Description of the Related Art In recent years, CVD (Chemical Va)
por Deposition (PVD) device, PVD (Phy
In a semiconductor manufacturing apparatus such as a physical vapor deposition (etching) apparatus and a flat panel display apparatus (hereinafter, referred to as an FPD apparatus), a processing capacity such as a plasma density is increased, for example. The processing temperature tends to be higher. Therefore, it is necessary to prevent the temperature of the silicon wafer (substrate) from unnecessarily rising, and to cool the silicon wafer (substrate) from the side of the substrate holding device that holds the silicon wafer in order to control the temperature. In addition, since the temperature of the substrate holding device drops when the processing is not performed, it is necessary to raise the temperature of the substrate holding plate to prevent a reduction in the processing speed. Therefore, conventionally, there has been a substrate holding device provided with a heating mechanism and a cooling mechanism.

[0003]

However, since the above substrate holding device is generally made of a single material such as a metal or a ceramic material, when a temperature gradient is generated in the device when heating or cooling, thermal strain is reduced. As a result, the substrate holding device was sometimes deformed. In particular, in the above-described semiconductor manufacturing apparatus and the like where high-precision processing is required, if the substrate holding apparatus is deformed, for example, a uniform film cannot be obtained with a film forming apparatus such as a CVD apparatus or a PVD apparatus. A problem arises in that uniform etching cannot be performed, and the quality of the processed substrate deteriorates.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and its main object is to provide a simple structure for heating / cooling used in a manufacturing apparatus such as a semiconductor device or an FPD apparatus or an inspection apparatus. An object of the present invention is to prevent deformation of a substrate holding device having a mechanism due to thermal strain.

[0005]

SUMMARY OF THE INVENTION The above-mentioned object is to provide a substrate
Holds and has a heating mechanism and a cooling mechanism for the substrate
A substrate holding device incorporating the heating mechanism.
Heat unit and cooling unit incorporating the cooling mechanism
By brazing, diffusion bonding or soldering.
The cooling unit,
Composed of a material with a higher coefficient of thermal expansion than the unit
To provide a substrate holding device characterized in that
Is achieved by Specifically, the heating unit is:
Titanium, molybdenum, tungsten and mainly
Alloy, iron-nickel alloy, iron-nickel-kobal
Alloys, aluminum nitride, alumina, etc.
4 × 10 at room temperature^-6(1 / ° C) to 10 × 10^-6(1 /
(° C).
Aluminum, stainless steel, copper and their main
15 × 10 at room temperature selected from solid alloys^-6(1
/ ° C) to 25 × 10 ^-6(1 / ° C)
It is good to consist of materials.

[0006]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view showing a schematic configuration of a substrate holding apparatus to which the present invention is applied, and FIG. 2 is a sectional view thereof. This substrate holding device has a substantially disc shape, and a heating unit 1 having a heating mechanism and a cooling unit 2 having a cooling mechanism are laminated, and both units 1 and 2 are integrally formed by brazing, diffusion bonding or soldering. Is joined to. Then, the substrate B to be processed is held on the heating unit 1.

In the heating unit 1, a large number of inorganic or organic heating elements 3 connected to an external power source (not shown) are buried to form a heating mechanism. Although the heating elements 3 have a linear shape (circular cross section) in this configuration, they may have any shape of a wire, a foil, or a particle. Here, the heating unit 1 is formed by joining and integrating two parts, one for holding the substrate and the other for joining with the cooling unit 2 in order to embed the heating element 3 therein.

Further, a number of refrigerant passages 4 are formed in the cooling unit 2. A cooling mechanism for cooling the substrate B is formed by circulating a gas or liquid refrigerant supplied from a cooling source (not shown) through the refrigerant passage 4. Here, the cooling unit 2 is also formed by joining and integrating two sides of the side to be joined to the heating unit 1 and the opposite side to define the refrigerant passage 4 therein similarly to the above. Become.

In FIG. 1, reference numeral 6 denotes a lead wire from the heating element 3, and reference numeral 7 denotes a pipe connecting the refrigerant passage 4 and a cooling source to circulate the refrigerant in the refrigerant passage 4.

Here, a material having a larger thermal expansion coefficient than the heating unit 1 is used for the cooling unit 2. In consideration of the plasma resistance or the possibility of integration by bonding, the heating unit 1 is made of titanium, molybdenum, tungsten, an alloy mainly containing them, iron-
It is desirable to select any one of a nickel-based low thermal expansion alloy, an iron-nickel-cobalt-based low thermal expansion alloy, and a ceramic material such as aluminum nitride and alumina. Also,
As the material of the cooling unit 2, it is desirable to select any of aluminum, stainless steel, copper and alloys mainly composed of them.

When the above material is selected for each unit, the thermal expansion coefficient of the material used for the heating unit 1 is 4 × 10 ⁻⁶ (1 / ° C.) to 10 × 10 ⁻⁶ (1 / ° C.) at room temperature. The coefficient of thermal expansion of the material used for the cooling unit 2 is in the range of 15 × 10 ⁻⁶ (1 / ° C.) to 25 × 10 ⁻⁶ (1 / ° C.) at room temperature.

The relationship between the thickness of the heating unit 1 and the thickness of the cooling unit 2 varies depending on the material to be used, the temperature to be used, and the allowable amount of deformation. The amount of deformation d of the surface of the substrate holding plate
(FIG. 3) must be suppressed to 70 μm or less.

When the above materials are selected as the materials of the respective units, the range of the thickness ratio is desirably 10: 1 to 1:10 in order to suppress the surface deformation d to 70 μm or less.

If the heating unit 1 is made of titanium or an alloy mainly composed of titanium, and the cooling unit 2 is made of aluminum, stainless steel or an alloy mainly composed of them, these have extremely poor plasma resistance and bonding property. Therefore, it is a particularly desirable material configuration among the above-mentioned material configurations.

In order to integrate the two units, a method such as fastening may be used. However, by integrating them by joining such as brazing, diffusion joining or soldering, heat transfer at the interface between dissimilar materials is performed. Efficiency is improving.

[0017]

EXAMPLE 1 Titanium (hereinafter, referred to as Ti) having a diameter of 200 mm was used as the material of the heating unit 1 and 20 mm in diameter as the material of the cooling unit 2.
0 mm aluminum (hereinafter, Al alloy) was selected.
These materials were brazed to the thicknesses shown in Table 1 to form a substrate holding device. The total thickness of each unit is 40m
m.

Example 2 Ti having a diameter of 200 mm was selected as a material of the heating unit 1 and a stainless alloy (hereinafter, SUS alloy) having a diameter of 200 mm was selected as a material of the cooling unit 2. These materials were brazed to the thicknesses shown in Table 1 to form a substrate holding device. The total thickness of each unit was 40 mm.

EXAMPLE 3 Molybdenum (hereinafter, referred to as Mo) having a diameter of 200 mm was used as a material for the heating unit 1, and 2 mm in diameter as a material for the cooling unit 2.
A 00 mm Al alloy was selected. These materials were brazed to the thicknesses shown in Table 1 to form a substrate holding device.
The total thickness of each unit was 40 mm.

Example 4 Tungsten (hereinafter, W) having a diameter of 200 mm was used as a material of the heating unit 1, and a diameter 2 was used as a material of the cooling unit 2.
A 00 mm Al alloy was selected. These materials were brazed to the thicknesses shown in Table 1 to form a substrate holding device.
The total thickness of each unit was 40 mm.

Example 5 Aluminum nitride (hereinafter, referred to as AlN) having a diameter of 200 mm was selected as a material of the heating unit 1, and an Al alloy having a diameter of 200 mm was selected as a material of the cooling unit 2. These materials were brazed to the thicknesses shown in Table 1 to form a substrate holding device. The total thickness of each unit was 40 mm.

Example 6 Alumina having a diameter of 200 mm (hereinafter, Al ₂ O ₃ ) was selected as a material of the heating unit 1, and an Al alloy having a diameter of 200 mm was selected as a material of the cooling unit 2. Table 1 shows these materials.
The substrate holding device was formed by brazing to the thickness shown in FIG. The total thickness of each unit was 40 mm.

Comparative Example 1 An Al alloy having a diameter of 200 mm and a plate thickness of 20 mm was selected as a material for the heating unit 1 and the cooling unit 2 and brazing was performed to form a substrate holding device.

Comparative Example 2 A SUS alloy having a diameter of 200 mm and a plate thickness of 20 mm was selected as a material for the heating unit 1 and the cooling unit 2 and brazing was performed to form a substrate holding device.

With respect to the substrate holding devices obtained in Examples 1 to 6 and the substrate holding devices obtained in Comparative Examples 1 and 2, the surface (heating side) was set to 200 ° C. and the back surface (cooling). Table 1 shows the results obtained with respect to the amount of deformation of the surface when (side) was 100 ° C.

[0026]

[Table 1]

In the first to sixth embodiments, the heating unit 1
By selecting an appropriate plate thickness for each constituent material of the cooling unit 2, the amount of surface deformation could be reduced to 70 μm or less. Further, it can be seen that by selecting an optimal thickness configuration, it is possible to obtain a substrate holding plate that is even less deformed.

On the other hand, the deformation amounts of Comparative Examples 1 and 2 made of a single material were 0.305 mm and 0.217 mm, respectively, and the surface deformation was 70 μm or more. In the case of the deformation amount seen in the comparative example, it is impossible to manufacture or inspect a good semiconductor device or FPD device.

[0029]

As is apparent from the above description, according to the substrate holding apparatus of the present invention, a heating unit having a built-in heating mechanism is made of a material having a relatively small thermal expansion coefficient.
By using a material with a larger coefficient of thermal expansion than the heating unit for the cooling unit with a built-in cooling mechanism and adjusting the thickness etc. of both, even if a temperature gradient occurs across both units of the substrate holding device, heat Strain is reduced, and deformation can be suppressed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of a substrate holding device to which the present invention is applied.

FIG. 2 is a cross-sectional view of the substrate holding device of FIG.

FIG. 3 is a diagram illustrating deformation of a substrate holding device due to heat.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heating unit 2 Cooling unit 3 Heating element 4 Refrigerant passage 6 Lead wire 7 Tube

Claims (5)

[Claims] 1. A substrate holding apparatus for holding a substrate and having a heating mechanism and a cooling mechanism for the substrate, wherein a heating unit incorporating the heating mechanism and a cooling unit incorporating the cooling mechanism are integrated. The substrate holding device, wherein the cooling unit is made of a material having a larger thermal expansion coefficient than the heating unit. 2. The heating unit according to claim 1, wherein said heating unit is 4 × 10 at room temperature.
^-6 (1 / ° C.) to 10 × 10 ⁻⁶ (1 / ° C.), and the cooling unit is formed of a material having a thermal expansion coefficient of 15 × 10 ⁻⁶ (1 / ° C.) to 25 × 10 ⁻ at room temperature. ^2. The substrate holding device according to claim 1, wherein the substrate holding device is made of a material having a thermal expansion coefficient of ⁶ (1 / ° C.). 3. The substrate holding device according to claim 1, wherein the two units are joined by brazing, diffusion bonding, or soldering. 4. The apparatus according to claim 1, wherein said heating unit and said cooling unit are stacked in a thickness direction, and the thickness ratio is 10: 1 to 1:10. The substrate holding device according to any one of the above. 5. The heating unit according to claim 1, wherein the heating unit is made of titanium, molybdenum, tungsten, and an alloy mainly containing them.
Nickel-based alloy, iron-nickel-cobalt-based alloy, a material selected from any of aluminum nitride and alumina, wherein the cooling unit is selected from aluminum, stainless steel, copper and any of the alloys based on them The substrate holding device according to any one of claims 1 to 4, wherein the substrate holding device is made of a material.