JP2000188279A - Electrostatically attractable transparent insulating substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an insulating substrate which can be set to a highly uniform temperature distribution and can obtain a highly uniform worked or formed film distribution. SOLUTION: On the surface which is brought into contact with the upper surface of an electrostatic chuck electrode 12 provided on a substrate electrode 9, namely, on the rear surface of a transparent insulating substrate 16, a transparent conductive film composed of an oxide film or a nitride or metallic thin film, the composition of which is controlled so that the light transmittance of the film in the visible region becomes >=80% and the electrical resistivity of the film becomes <=1012 Ωcm, is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for manufacturing electronic parts and optical parts, such as a dry etching apparatus, a plasma CVD apparatus, a sputtering apparatus and an ion implantation apparatus, which is held on a substrate electrode by electrostatic attraction to perform required processing or processing. The present invention relates to an insulating transparent substrate such as a glass substrate which is made to be modified.

[0002]

2. Description of the Related Art Conventionally, when a glass substrate is processed using an electronic component and an optical component manufacturing apparatus, the glass substrate cannot be electrostatically attracted. Was used. FIG. 2 of the accompanying drawings shows an example of an etching apparatus using such a mechanical chucking method.

In the apparatus shown in FIG. 2, three magnetic field coils C1, C2,
C3 and the high-frequency antenna D are arranged, and the high-frequency antenna D
Are connected to a high frequency power supply E. An etching gas inlet (not shown) is provided near the upper flange of the top plate F at the top of the vacuum chamber A. A substrate electrode G is disposed below the vacuum chamber A via an insulator H. The substrate electrode G is connected to a high frequency power source J for biasing via a blocking capacitor I. The glass substrate K to be processed is fixed on the substrate electrode G by the mechanical chucking L.

In the operation of the etching apparatus configured as described above, the etching gas is supplied to the top plate F at the top of the vacuum chamber A.
Is introduced into the vacuum chamber A from the etching gas inlet close to the upper flange of the vacuum chamber A, and the dielectric cylindrical side wall B on the upper part of the vacuum chamber A
A high-frequency power is applied from a high-frequency power source E to a high-frequency antenna D provided outside the device to form plasma. Vacuum chamber A
A high-frequency power for bias is applied from a high-frequency power source J to a substrate electrode G below the substrate electrode. In this case, the substrate electrode G floating with the blocking capacitor I
Becomes a negative self-bias potential, and positive ions in the plasma are attracted to etch the substance on the substrate K. A gas such as He is introduced from below the substrate electrode G, and the electrode G
The heat is transferred between the substrate K and the substrate K, and the temperature of the substrate K is controlled.

[0005]

For example, in the etching apparatus shown in FIG. 2, the ions in the plasma are attracted by the self-bias electric field generated at the substrate electrode G, and the ions bombard the surface of the substrate. Occurs. Therefore, by introducing a gas serving as a heat medium between the lower part of the substrate and the substrate electrode to improve heat transfer, and by releasing the amount of heat generated on the substrate through the substrate electrode, the substrate is maintained at a constant temperature. I have.

However, in the conventional mechanical fixing method such as the mechanical chucking method, the adhesion between the substrate and the substrate electrode is inferior, as can be inferred from the fact that it is basically three-point contact. The distance between the substrate and the substrate electrode is not constant, and the pressure of the introduced gas is not constant. As a result, there is a problem that a large temperature distribution is obtained and uniform processing cannot be performed. Therefore, an object of the present invention is to provide an insulative transparent substrate such as a glass substrate or the like in which the uniformity of temperature distribution can be obtained by improving the adhesion between the substrate and the substrate electrode.

[0007]

In order to achieve the above-mentioned object, the light transmittance in the visible region becomes 80% or more on the back surface of the glass substrate, that is, on the surface in contact with the substrate holding table, that is, on the substrate electrode or on the inside thereof. A transparent conductive film is provided so that it can be fixedly adhered to the substrate holder by electrostatic attraction with an electrostatic chuck electrode provided on the uppermost surface of the substrate holder.

With this configuration, the glass substrate is closely fixed to the substrate holding table by the electrostatic chuck, so that the distance between the electrostatic chuck electrode on the substrate holding table and the glass substrate is maintained constant, The heat transfer amount of the gas serving as the medium is also constant, and the temperature distribution becomes uniform. Therefore, for example, in the case of plasma etching, the amount of heat flowing from the plasma can be uniformly released to the substrate holding table over the entire substrate, and the etch speed distribution becomes uniform. Further, by setting the light transmittance in the visible region of the conductive film formed on the back surface to 80% or more, the conductive glass can be used as it is without removing the conductive film.

[0009]

According to one embodiment of the present invention, a glass substrate mounted on a surface of a substrate electrode provided in a vacuum chamber and processed by plasma or the like is provided with a surface of the substrate electrode. A transparent conductive film is provided on the surface side of the glass substrate to be contacted to form an electrostatic chucking surface, and a pattern formed of a plurality of conductors is buried in the insulator provided on the surface of the substrate electrode. The configured plate-shaped electrostatic suction device is configured to be capable of electrostatic suction.

The transparent conductive film is made of an oxide such as In, Ti, Sn or the like or an oxide or nitride of a compound, a mixture or an alloy thereof, and has a light transmittance of 8 in the visible region of the transparent conductive film.
The electrostatic attraction surface of the glass substrate can be configured to be 0% or more. Alternatively, the transparent conductive film may be formed of a metal thin film having a thickness of 100 nm or less, and the electrostatic attraction surface of the glass substrate may be configured so that the light transmittance in the visible region is 80% or more. Also,
The transparent conductive film is made of a thin film of an oxide, a nitride or other compound whose composition is controlled so as to have a resistivity of 10 ¹² Ωcm or less, and is made of glass such that the light transmittance in the visible region is 80% or more. An electrostatic attraction surface of the substrate can be configured. further,
The electrostatic attraction surface of the glass substrate can also be provided inside the glass substrate, in which case the thickness of the glass layer of the glass substrate on the substrate electrode that contacts the electrostatic attraction device is preferably 10
Should be less than μm.

An embodiment of the present invention will be described below with reference to FIG. 1 of the accompanying drawings. FIG. 1 shows an example applied to an etching apparatus for etching a glass substrate according to the present invention. In FIG. 1, reference numeral 1 denotes a vacuum chamber having a cylindrical side wall 2 made of, for example, quartz, on the outside of which three coils 3, 4, 5 constituting a magnetic field generating means are arranged on substantially the same circumference along an axis. It is provided along. As shown in the drawing, the same constant current in the same direction is applied to the upper and lower two electromagnetic coils 3 and 5, and the opposite current is applied to the intermediate coil 4. As a result, a position where a continuous magnetic field is zero is formed inside the cylindrical side wall 2 near the level of the intermediate coil 4, and a circular magnetic neutral line is formed.

Between the intermediate coil 4 and the cylindrical side wall 2, a high-frequency electric field generating antenna 6 serving as electric field generating means is provided, and is connected to a high-frequency power supply 7 for plasma generation. A substrate electrode 9 is provided in the lower part of the vacuum chamber 1 via an insulator 8, and the substrate electrode 9 is connected to a high-frequency power source 11 for bias via a capacitor 10. An electrostatic chuck electrode 12 is provided on the substrate electrode 9. The electrostatic chuck electrode 12 is formed in a plate shape by embedding a pattern composed of a plurality of conductors 14 in an insulator 13. Electric chuck power supply 15
Connected to. A glass substrate 16 is placed on the electrostatic chuck electrode 12
Is attached. As described above, the glass substrate 16 has a light transmittance in the visible region of 80% or more and a resistivity of 10% on the side in contact with the upper surface of the electrostatic chuck electrode 12, that is, on the back surface.
^A transparent conductive film made of an oxide film, a nitride, or a metal thin film whose composition is controlled to be ¹² Ωcm or less is formed.
Further, the flow path of the gas flowing between the glass substrate 16 and the electrostatic chuck electrode 12 is not shown.

A counter electrode 17 made of a conductive material is provided at the upper end of the cylindrical side wall 2 of the vacuum chamber 1 so as to face the substrate electrode 10. The counter electrode 17 is a shower plate 18 for introducing an etching assist gas. The shower plate 18 communicates with an etching assist gas source (not shown) through a gas passage (not shown) provided in the counter electrode 17. The vacuum chamber 1 is evacuated from an exhaust port 1a by an evacuation system 19. Further, although not shown, the vacuum chamber 1 is provided with a gas introduction unit for introducing an etching main gas.

The operation and operation of the illustrated apparatus configured as described above will be described. Using the apparatus shown in FIG. 1, the power of the plasma generating high frequency power supply 8 (13.56 MHz) is 1.0 KW, the power of the substrate bias high frequency power supply 12 (13.56 MHz) is 0.8 KW, and the pressure is 3 mT.
Orr was introduced by introducing 10 sccm (10%) of C ₄ F ₈ as an etching main gas. At that time, the etching rate of quartz was about 810 nm / min ± 2.83%. The etch rate and its distribution under the same conditions in the conventional device configuration are 840 nm.
/ Min ± 7.1%. By making the temperature distribution uniform, the etch rate is somewhat reduced, but the temperature distribution of the substrate is made uniform, so that high etch rate uniformity can be obtained.

In the illustrated embodiment, an example in which the present invention is applied to an etching apparatus has been described. However, highly uniform and uniform film distribution can be obtained also in plasma CVD. Needless to say, it can be expected that a highly uniform impurity distribution can be similarly obtained even when applied to an ion implantation apparatus.

As described above, according to the present invention, on the side in contact with the upper surface of the electrostatic chuck electrode provided on the substrate electrode, that is, on the back surface side, the light transmittance in the visible region becomes 80% or more and the resistance is increased. A transparent conductive film composed of an oxide film, nitride, or metal thin film whose composition is controlled so that the rate is 10 ¹² Ωcm or less is formed, so that it is highly uniform when processing an insulating substrate such as a glass substrate. Temperature distribution, and highly uniform processing or film formation distribution can be obtained.
Therefore, the present invention greatly contributes to processing and film formation of insulators used for electronic components and optical components.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of an etching apparatus used for etching an insulating substrate according to the present invention.

FIG. 2 is a schematic sectional view of a conventional etching apparatus.

[Explanation of symbols]

 1: vacuum chamber 2: cylindrical side wall 3, 4, 5: coil forming magnetic field generating means 6: high frequency electric field generating antenna forming electric field generating means 7: plasma generating high frequency power supply 8: insulator 9: substrate electrode 11: Bias RF power supply 12: Electrostatic chuck electrode 16: Glass substrate

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5F004 AA01 BA20 BB13 BB18 BB21 BB22 BB28 DA00 DB00 5F045 AA08 AA19 AC02 AF07 BB02 DP01 DP02 DP03 DQ10 EF05 EH01 EH02 EH11 EH16 EM01 EM05

Claims (5)

[Claims] 1. An insulating transparent substrate mounted on a surface of a substrate electrode provided in a vacuum chamber and treated with plasma or the like. A static conductive surface is formed by providing a conductive film, and is provided on a surface of the substrate electrode. An insulative transparent substrate capable of electrostatic attraction, characterized in that it is configured to be capable of electroadsorption. 2. The transparent conductive film is made of an oxide such as In, Ti, Sn or the like or an oxide or nitride of a compound, a mixture or an alloy thereof, and has a light transmittance of 8 in a visible region of the transparent conductive film.
The insulating transparent substrate capable of electrostatic attraction according to claim 1, wherein the electrostatic attraction surface of the insulating transparent substrate is configured to be 0% or more. 3. The electrostatic adsorption surface of an insulating transparent substrate, wherein the transparent conductive film is made of a metal thin film having a thickness of 100 nm or less, and a light transmittance in a visible region is 80% or more. Item 2. An insulative transparent substrate according to item 1, which is capable of electrostatic attraction. 4. The transparent conductive film is made of a thin film of an oxide, a nitride, or another compound whose composition is controlled so as to have a resistivity of 10 ¹² Ωcm or less, and has a light transmittance of 80% in a visible region.
The insulative substrate capable of electrostatic attraction according to claim 1, wherein the electrostatic attraction surface of the insulative substrate is configured as described above. 5. The insulation capable of electrostatic attraction according to claim 1, wherein the electrostatic attraction surface of the insulative transparent substrate is provided inside the insulative transparent substrate. Transparent substrate.