JPS5950166A - Thin film forming device by glow discharge - Google Patents

Abstract

PURPOSE:To enable the suppression of the formation of powder that influences adversely the characteristics of the thin film to be formed, by providing an openable and closable shielding plate in the recessed part of the inside wall surface in the region of a reaction vessel where glow discharge is induced. CONSTITUTION:A prescribed substrate 3 is installed on a sample support base 2 in a reaction vessel 1. A valve 4 is first opened to evacuate the inside of the vessel 1 to a high degree of vacuum through a high vacuum evacuation system A. The valve 4 is then closed and a valve 6 is opened to introduce gaseous SiH4 through a gas introducing pipe 7 into the vessel 1. After the inside of the vessel 1 attains a prescribed reduced pressure, a valve 5 is opened to maintain the inside of the pressure under a prescribed pressure by the evacuation system B using a mechanical booster pump. High frequency electric power is applied to induce glow discharge, thereby forming an amorphous Si film on the substrate 3. Since the part up to the valve 4 is recessed part 8 and causes the intrusion of plasma or abnormal discharge, the part 8 is covered with a shielding plate 9.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement in an apparatus for forming a thin film by glow discharge.

[Technique of the invention νFJ background and its problems] Normally α) In a glow discharge film forming apparatus, the inner wall surface fK of the area where glow discharge occurs, that is, the inner wall surface fK of the tail and the valley, is, for example, t(b Makabeゎ1 The opening for connecting to the air thread, the opening to accommodate the gauge boat into which the Makabe gauge is inserted, and the window for monitoring the discharge condition are formed as recesses. .

However, when glow discharge is performed in this state, plasma also invades these recesses, so for example, in the case of cloro group%L using monolan, brown powder is formed and the inner wall is cornered, or a pollo cand discharge is generated. The discharge often became unstable. This powder must be removed immediately after the completion of one film forming process to avoid negative effects such as negative deterioration of the burnt film and generation of hinholes on the subsequent no-glow discharge film formation. It is difficult to completely remove objects due to restrictions such as the operator's hands not being able to penetrate that far. Furthermore, when hollow cant discharge or abnormal discharge occurs, there is a drawback that the properties of the thin film itself become poor.

[Purpose of the invention]

The present invention improves the above-mentioned drawbacks, and has a young fruit that suppresses the generation of powder that causes abnormal discharge in the reaction vessel that generates glow discharge, and that adversely affects the properties of the formed film. An object of the present invention is to provide a thin film forming apparatus using glow discharge.

[Invention team]

In order to achieve the above object, the present invention is characterized in that the recess formed on the inner wall surface of the reaction vessel is provided with a shielding plate that can be opened and closed as required.

This shielding plate serves to prevent plasma from entering the forward bending recess, and at the same time to suppress abnormal radiation caused by the geometrical non-uniformity (unevenness) of the inner wall of the reaction vessel. be.

[Effects and Disappointments of the Invention] Kinoi IJJ makes it possible to raise q-= the glow release tW that has reacted and remained stable in the container, and suppresses the generation of imitation powder in the four parts due to gas phase reactions that cause film quality deterioration. This became i5J Noh.

More specifically, according to the present invention, for example, when forming an amorphous silicon film, ordinary monosilane gas (Sin
,) The glow discharge decomposition of 4 ≧ brown powder is generated in the reaction vessel, and extremely stable discharge can be obtained. Thickness, dark conductivity, light conductivity 7
It is recognized that there is almost no paranki in characteristics such as the L rate.

Also, since the brown powder in the recess is hot,
The cleaning process inside the reaction vessel after film formation was also significantly shortened, which was an undesirable effect in terms of productivity.

[Embodiments of the invention]

The figure is a plan view schematically showing a claw discharge device according to the present invention. Inside the reaction chamber b1, there is a sample support stand 2, and the tyranny 3 of l')Iinε is installed on this sample support stand 2. Further, this reaction vessel I is connected to the sieve Makabe evacuation thread A via the vacuum valve 4, and is also connected to the Makabe valve 5.
Exhaust by mechanical booster bong, ML
IK connected.

In the Jlu 'iF+ operator +11LL, first open the valve 4 and use the high vacuum evacuation line A to vacuum the reaction vessel I by 5x.
After closing valve 4, open stop valve 6, and introduce monosilane gas into reaction vessel I through gas introduction layer 7 at 39 SC.
Introduced at the end of the commercial. Ronica in reaction vessel I is l'
After YorrllC, open valve 5 and 0.5 To
rr Do not keep the VC and continue exhausting the lit power (13
, 56MJ-1z) to generate a glow discharge.
This results in the formation of an amorphous silico/film on the group &3.

At point 7), the part up to the vacuum valve for connecting to the city vacuum exhaust side is in the recess 8°C, and if this continues, plasma will enter the eye and cause abnormal discharge. . Therefore, in this embodiment, this concave gp B is covered with a shielding plate 9.

This shielding plate 9 is made of stainless steel like the reaction vessel 1, and has a structure that can be opened and closed by sliding it laterally as shown by the arrow.

By shielding the concave portion 8 with the shielding plate 9, no abnormal discharge occurs during glow discharge, and since no plasma enters the concave portion 8, no brown powder is generated in this area. . For this reason, the deterioration caused by foreign trade of Pinohole etc. is eliminated, and a film with good tax-inclusive properties can now be obtained.

Also, there is a brown powder in the recess 8 up to the valve 4.
Maintenance of the device is easier because it does not cause damage.

In this embodiment, the shielding plate 9 is made of steel/resistance material, but it is not limited to this, and any material that does not affect the characteristics of the thin film to be formed may be used, such as aluminum, iron, etc.
Nickel, copper, Teflon, polyimide, glass, quartz, etc. may be used.

Also, the opening/closing method may be manual or automatic, and the opening/closing method may also be a one-way type other than a sliding type, such as a one-way type that rotates around a single point.'' (Of course).

4, Opening of a Mountain] is a plan view of an apparatus for explaining an embodiment of the invention.

I...Counter pressure, container, 2...Sample support stand, 3...Sample storage plate), 4.5...True valve, 6...Stop valve, 7. Gas, etc. large white', 8. ... recess, 9... shielding plate.

Patent attorney representing applicant: Takehiko Suzue

Claims (1)

[Claims] (IJ) In an apparatus that decomposes a source gas to form a thin film on a predetermined substrate by generating glow discharge in a reaction vessel, IJ is formed on the inner wall surface of the area where glow discharge occurs in the reaction vessel. A #&! forming device by Crow group 'N□, which is characterized by having shielding plates that can be opened and closed provided on the four parts that are exposed to the air. A thin film forming apparatus using glow discharge according to claim 1. (3) A thin film forming apparatus using glow discharge according to claim 1, wherein the thin film is an amorphous thin film.