JPH05315300A - Dry etching device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of uneven parts, such as cloudy spots, etc., in a glass substrate placed on a sample stage due to an etching gas infiltrating to the rear surface of the glass substrate by providing a gas supplying device which makes a gas to flow into the gap between the rear surface of the substrate and the sample stage. CONSTITUTION:A glass substrate B is fixed on a sample stage 5 with a gap 8 in between by means of pins 6. After an etching chamber 1 is evacuated to a vacuum state, the substrate B is etched by blowing an etching gas from a gas scattering nozzle 3 through a gas shower 2. At the same time, a gas supplying device 7 blows an inert gas into the gap 8 on the rear side of the substrate B from blowing holes on the stage 5. Since the gas pressure in the gap 8 becomes higher that in the chamber 1 on the surface side of the substrate B due to the inert gas, the infiltration of the etching gas to the rear side of the substrate and, therefore, the occurrence of uneven parts, such as cloudy spots, etc., in the substrate B can be prevented. The gas blown into the gap 8 does not react to the rear surface of the substrate B, because the gas is the inert gas.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry etching apparatus for improving the quality of substrates.

[0002]

2. Description of the Related Art As a conventional dry etching apparatus,
For example, the configuration shown in FIG. 2 is known.

The dry etching apparatus shown in FIG.
There is an etching chamber 1 capable of having a vacuum inside, and a gas shower 2 having a plurality of ejection holes on the lower surface is provided above the inside of the etching chamber 1, and the gas shower 2 includes: An etching gas is supplied by the gas dispersion nozzle 3. On the other hand, the etching chamber 1 is provided with an exhaust pipe 4 through which the etching gas after etching is discharged to the bottom.

A sample table 5 is mounted on the bottom surface of the etching chamber 1, and a thin film transistor array having a multi-layer structure composed of a thin film semiconductor layer and an insulating layer is formed on the sample table 5 so as to face the gas shower 2. A glass substrate B is placed and fixed to the sample table 5 with pins 6.

Then, the glass substrate B is fixedly set on the sample table 5 with the pin 6, the entire etching chamber 1 is placed in a vacuum state, the etching gas is ejected from the gas shower 2 through the gas dispersion nozzle 3, and the glass substrate B is ejected. The etching is done on the top.

[0006]

However, in the case of the dry etching apparatus shown in FIG. 2, when the glass substrate B is fixed to the sample table 5 with the pins 6, the glass substrate B
Due to the warp and the flatness of the sample table 5, a slight gap is formed between the sample table 5 and the glass substrate B. Then, the etching gas ejected from the gap by the gas shower 2 is
There is a problem in that unevenness such as white turbidity occurs on the glass substrate B by getting around to the back surface of the glass substrate B.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a dry etching apparatus which improves the quality of a substrate.

[0008]

The present invention provides a dry etching apparatus in which a substrate is placed on a sample table, and a layer structure formed on the substrate is dry-etched with an etching gas. A gas supply device for injecting gas is provided in a gap formed between the sample table and the sample table.

[0009]

According to the present invention, since the gas is supplied by the gas supply device to the gap between the back surface of the glass substrate placed on the sample table and the sample table, the etching gas is less likely to enter the back surface of the substrate. Reaction does not easily occur on the back surface of the substrate, and the quality of the substrate is improved.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the dry etching apparatus of the present invention will be described below with reference to the drawings. The portions corresponding to the conventional dry etching apparatus shown in FIG. 2 will be described with the same reference numerals.

The dry etching apparatus shown in FIG.
There is an etching chamber 1 capable of having a vacuum inside, and a gas shower 2 having a plurality of ejection holes on the lower surface is provided above the inside of the etching chamber 1, and the gas shower 2 includes: An etching gas is supplied by the gas dispersion nozzle 3. On the other hand, the etching chamber 1 is provided with an exhaust pipe 4 through which the etching gas after etching is discharged to the bottom.

A sample table 5 is mounted on the bottom surface of the etching chamber 1, and a thin film transistor array having a multi-layer structure having a thin film semiconductor layer whose surface faces the gas shower 2 and an insulating layer is mounted on the sample table 5. Glass substrate B is mounted. Further, a gas supply device 7 to which an inert gas such as helium or argon gas is supplied is attached to the sample table 5, and an inert gas supplied from the gas supply device 7 is provided on the upper surface of the sample table 5. A large number of ejection holes for ejecting gas toward the back surface of the glass substrate B are formed. The glass substrate B is fixed to the sample table 5 with a pin 6 having a gap 8 between the back surface of the glass substrate B and the upper surface of the sample table 5.

Next, the operation of the above embodiment will be described.

First, the glass substrate B is fixed on the sample table 5 by the pin 6 with a gap 8 between the sample table 5 and the back surface of the glass substrate B. Then, the etching chamber 1 as a whole is evacuated, etching is supplied from the gas dispersion nozzle 3 to the gas shower 2, and the glass shower B is supplied from the gas shower 2.
Etching gas is ejected toward the substrate to etch the glass substrate B.

At the same time as the etching gas is jetted from the gas shower 2, an inert gas such as helium or argon gas is supplied to the sample stage 5 from the gas supply device 7, and the glass substrate is discharged from the jet holes on the sample stage 5. Inert gas is jetted toward the back surface of the glass substrate B into the gap 8 between the back surface of B and the top surface of the sample table 5. The pressure of the gap 8 on the back surface of the glass substrate B becomes equal to or higher than the pressure of the etching chamber 1 on the front surface side of the glass substrate B due to the jetting of this inert gas, so that the etching gas is prevented from flowing around to the back surface of the glass substrate B. Moreover, since the gas jetted into the gap 8 is an inert gas, it does not react with the back surface of the glass substrate B, and prevents unevenness such as clouding that occurs on the glass substrate B.

[0016]

According to the dry etching apparatus of the present invention, since the gas is supplied by the gas supply device to the gap between the back surface of the glass substrate placed on the sample table and the sample table, the etching gas is used as the back surface of the substrate. Since it does not easily go around, the reaction does not easily occur on the back surface of the substrate, and the quality of the substrate is improved, so that the yield and reliability can be improved.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of a dry etching apparatus of the present invention.

FIG. 2 is an explanatory diagram showing a conventional dry etching apparatus.

[Explanation of symbols]

 5 sample stage 7 gas supply device 8 gap B glass substrate

Claims (1)

[Claims] 1. A dry etching apparatus in which a substrate is placed on a sample table and a layer structure formed on the substrate is dry-etched with an etching gas, in a gap formed between the back surface of the substrate and the sample table. A dry etching apparatus characterized in that a gas supply device for flowing a gas is provided in the.