JPS58208120A - Apparatus for forming thin silicon film - Google Patents

Abstract

PURPOSE:To enhance the yield by covering the inside of a reaction chamber with a flexible wire net when a reactive gas is decomposed to form a thin silicon film on a substrate. CONSTITUTION:A flexible wire net 6 is suspended at the inside of the side wall 11 of a reaction chamber 1 to cover the inside of the chamber 1. The chamber 1 is evacuated, a reactive gas is introduced, and by causing glow discharge, the reactive gas is decomposed to form a thin silicon film on a substrate. When the amount of silicon deposited on the net 6 is increased by repeating work using the apparatus, the deposited silicon is shaken off by applying mechanical force to the net 6. Thus, the formation of each thin silicon film is carried out in the clean reaction chamber 1, so the yield is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thin film silicon deposition apparatus using a plasma CVD method.

FIG. 1 shows such a thin film silicon ablation device, in which a reaction chamber 1 has a horizontally positioned susceptor 2 and an electrode 3 facing it. A substrate (not shown) is placed on top of the susceptor 2, the interior space of the reaction chamber 1 is made completely solid by exhausting air through the exhaust port 4, silane gas is introduced through the gas introduction tube 5, and a high-frequency filter is placed between the susceptor 2 and the counter electrode 3. When a glow discharge is generated by applying a direct current voltage or a direct current voltage, the monosilane is decomposed and a thin film of amorphous silicon (a-81) is formed on the substrate heated by the heater built in the susceptor 2. However, in this case, a-8l also adheres to the wall 11 of the reaction chamber 1, and when it becomes thick, it peels off and falls. This Sl
The fall is most common before the growth of a-81g, when the temperature rise of the wall 11 is maximum. The wall 11 is warmed by heat radiation from the susceptor 2 and adheres to the plate. This minute a-
Since the a-8i film grows on the 8l particles, this causes defects such as pinholes, causing a decrease in yield.

An object of the present invention is also to provide a thin film silicon production device with a high yield in which silicon particles do not fall onto the substrate surface due to the wall force of the reaction chamber.

This objective is achieved in that the inner surface of the reaction chamber is lined with a flexible wire mesh.

Embodiments of the present invention will be described below with reference to FIG. A thin film silicon deposition apparatus shown in FIG. 2 was used. Using this device, a voltage is applied between the susceptor 2 and the electric plate 3 in the same way as in the case of Fig. 1 to eliminate the glow discharge, and when monosilane is decomposed, a-8i grows on the substrate and at the same time gold N@
6 also has a-8i or an intermediate product attached to it. By repeating the thin M chemical formation process, this deposit becomes thicker, and the wire mesh 6
Before there is a risk of the substrate falling, the deposits are mechanically shaken off through a wire mesh when the reaction chamber 1 is opened to take out the substrate. It is effective to perform mechanical shaking by bending and stretching the wire mesh 6. Therefore, the wire mesh 6 needs to have flexibility.

Wire mesh 6 is good. If it is made of thick wire with a small mesh, reaction compounds will easily adhere to it, and it will also tend to peel off during bending and stretching. After cleaning the deposits such as A-8i that have been shaken off, if the top of the reaction Ml is placed over the susceptor 2 on which the substrate is placed, the thin film silicon formation process can be carried out in the clean reaction chamber 1. As a result, defects do not occur in the silicon thin film that resides on the substrate.

In the example shown in Fig. 2, the wire mesh is attached only to the inner surface of the side wall 11 of the reaction chamber, but it is also effective to install it on the ceiling of the reaction chamber because it can prevent reaction products from adhering to the ceiling wall. .

As described above, the present invention covers the inner surface of the reaction chamber of a thin film silicon formation apparatus with a flexible wire mesh, and allows the reaction compound to adhere to the wire mesh, so that the amount of adhesion is large. This adhesion A゛ before it comes to be.

A-8i is mechanically shaken and attached to a thin film chemically formed substrate.
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This prevents the falling of gourds, seeds, etc., and allows the production of defect-free silicon thin films on two-dimensional substrates at a high yield, making it extremely effective for manufacturing amorphous silicon solar cells.

[Brief explanation of the drawing]

6...wire mesh.

Claims (1)

[Claims] 1) In a system that generates a glow discharge in a fully evacuated reaction chamber and decomposes the introduced reaction gas to produce a silicon thin film on the substrate, the inner surface of the reaction chamber is covered with a flexible wire mesh. What! Thin film silicon production device with P# characteristics.