JPH05160025A - Film formation device - Google Patents

Abstract

PURPOSE:To facilitate the cleaning work of a film formation chamber whereto any flakes or foreign matters during the film formation step adhere for increasing the rate of operation and improving the formed film quality. CONSTITUTION:The title film formation device is fitted with a substrate electrode arranged at specific interval from the inner bottom part of an inner chamber 12 forming an independent film formation space in outer chamber 11 as well as an exhaust hole 13 passing through the outer chamber 11 side beneath the substrate electrode. Through these procedures, the cleaning work of the inner chamber 12 only wherein the film forming constituent is deposited can suffice for the title film formation device thereby enabling the formed film thickness to be made even.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film forming apparatus for forming a thin film on a member to be film-formed by a gas phase or a chemical reaction in a vacuum atmosphere space or a space isolated from the atmosphere.

[0002]

2. Description of the Related Art As a film forming apparatus of this kind for forming a required thin film on the surface of a film forming member (hereinafter referred to as a substrate) such as an insulating substrate or a semiconductor substrate, a CVD apparatus and a plasma CV
A vapor deposition device such as a D device or a vacuum sputtering device is known. 2. Description of the Related Art In recent years, plasma CVD processing has been frequently used in a thin film forming process in manufacturing a semiconductor device or a liquid crystal display device.

Particularly, plasma CVD is a method of reacting a gaseous substance (processing gas) in non-equilibrium plasma to deposit new solid species on a substrate, and processing gas is used in a film forming chamber which is a vacuum processing chamber. (For example, silane gas) is activated (radicalized) by applying high frequency (RF) power or DC power energy, and a thin film (eg, amorphous silicon film) is generated and deposited on the substrate.

FIG. 4 is a cross-sectional view for explaining the schematic structure of a conventional plasma CVD apparatus, in which 01 is a film forming chamber, 02 is a substrate transfer preliminary chamber, 03 is a substrate tray, and 04 and 05 are processing gas introductions, respectively. , A discharge pipe, 06 is a radio frequency (RF) power supply, and 07 is a substrate. In the figure, a substrate 07 which is a film formation target member is placed on a substrate electrode 032 of a substrate tray 03, and a processing gas is introduced into a film forming chamber 01 in a vacuum atmosphere from an introduction pipe 04, and the processing gas is supplied to a high frequency. Power supply 06 to R
The required film is formed by activating (radicalizing) the RF power energy applied to the F electrode 031 to cause a chemical reaction on the surface of the substrate 07. The processing gas after being involved in the film formation is discharged from the discharge pipe 05.

The substrate tray 03 has a structure in which an RF electrode 031 and a substrate electrode 032 are held opposite to each other by a quartz or ceramic insulating rod 033. The substrate tray 03 can be transferred to the substrate transfer auxiliary chamber 02 when the substrate is exchanged by releasing the shutter 034, and the shutter 0 can be released without breaking the vacuum atmosphere of the film forming chamber 01 and the substrate transfer auxiliary chamber 02.
34 and gate 022 are opened / closed and gate 022 is opened.
Substrate 0 transferred from the transfer station adjacent to
7 is received, and the film-formed substrate is transferred to the transfer stage.

Japanese Patent Application Laid-Open No. 59-10224 or Japanese Patent Application Laid-Open No. 2-29 discloses a conventional technique for forming a desired film on a surface of a substrate by using such a film forming chamber.
No. 4018 can be cited.

[0007]

In the above-mentioned prior art, the substrate carrying tray 03 has the RF electrode 031 and the substrate electrode 0.
32 is supported by an insulating rod 033, and the substrate is carried in / out from between the insulating rods 033, and the film forming space is constituted by a single film forming chamber 01. Therefore, when the film forming process is continued, the film forming components are deposited on the structure of the substrate tray 03 and the inner wall of the film forming chamber 01, and flakes separated from the film adhere as dust to the surface of the substrate 07 to improve the film forming quality. Lower. In particular,
Since a large amount of film-forming components adhere to the wall surface of the film-forming chamber 01 having a large area, it is necessary for the film-forming chamber 01 to regularly remove the deposition of the film-forming components together with the substrate transport tray 03.

Further, the processing gas entered from the introduction pipe 04 is
The space of the film forming chamber 01 and the substrate 0 placed on the substrate tray 03
7 is discharged to the discharge pipe 05 through the vicinity of
Does not act evenly on the surface of. Therefore, there is a problem that the film formed on the substrate 07 becomes nonuniform. As described above, in the conventional technique, the film formation chamber for performing the film formation process on the substrate that is the film formation target forms a single space. The film-forming components are deposited on the inner wall of the substrate, and these flakes act as foreign matter to affect the film-forming state on the substrate surface, and the film formed on the substrate is not uniform, which deteriorates the film-forming quality.

In order to avoid the adverse effects of the flakes, it is necessary to regularly clean or disassemble the film forming chamber 01. Since the cleaning operation of the film forming chamber is the cleaning of the entire film forming chamber including the disassembly of the substrate tray 03, it takes a lot of time and labor. for that reason,
There is a problem that the operating rate of the film forming apparatus is significantly reduced.

An object of the present invention is to solve the above-mentioned problems of the prior art, to facilitate the cleaning work of the film forming chamber where flakes and foreign substances adhere to the film during the film forming process, and to suspend the film forming apparatus for the cleaning time. It is an object of the present invention to provide a film forming apparatus in which the operation rate is shortened, the operating rate is improved, and the film forming quality is improved.

[0011]

In order to achieve the above object, the present invention provides a gas discharge structure which has a double structure in a film forming chamber to limit a film forming space and to make a gas flow uniform on a substrate surface. It is characterized by having. That is, FIG. 1 is a schematic plan view showing only a main part of a film forming apparatus relating to plasma CVD for explaining the entire structure of the film forming apparatus according to the present invention. As shown in FIG. And an inner chamber 12 fixed inside the outer chamber 11 so as to form an independent film forming space in the vacuum atmosphere formed by the outer chamber 11. Has a substrate electrode 14 arranged at a predetermined distance from the inner bottom thereof, and a gas discharge port 13 penetrating to the outer chamber 11 side at the center of the inner bottom and directly below the substrate electrode. It is characterized by

Although FIG. 1 shows the configuration of the present invention as a schematic configuration diagram of a plasma CVD type film forming apparatus, the present invention is not limited to such a configuration, and a normal pressure CV is used.
The present invention can be applied to D, low pressure CVD method, vacuum sputtering apparatus and other vapor deposition apparatuses in general.

[0013]

The film forming chamber 10 has a double structure of the outer chamber 11 and the inner chamber 12 provided in the outer chamber 11, and the inner chamber 12 forms an independent space for film formation. Therefore, the film-forming components associated with the film-forming process will adhere only to the inner chamber 12, and cleaning work for removing flakes will be sufficient if only this inner chamber 12 is used. Therefore, labor can be saved, and a reduction in the operating rate of the film forming apparatus can be avoided.

Further, since the gas outlet 13 is provided in the center of the bottom of the inner chamber 12 and directly below the substrate electrode 12-4, the gas flow acting on the surface of the substrate becomes uniform and the film thickness produced is uniform. Become. Alternatively, by providing the gas discharge ports 13 at the four corners of the bottom of the inner chamber 12, the same effect as described above can be obtained.

[0015]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 2 is a vertical cross-sectional view for explaining one embodiment of the film forming chamber in the film forming apparatus according to the present invention, where 10 is a film forming chamber, 11 is an outer chamber, 12 is an inner chamber, 12-3 is a conductive plate, 12-4 is a substrate electrode, 12-
5 is a gas introduction hole, 13 is a gas outlet, 12-8 is an insulator, 14 is a substrate electrode, 15 is an RF electrode, 15-1 is a conductive contact spring, 15-2 is a gas introduction tube, and 15-3 is 15-3. A gas release hole, 20 is a substrate.

In FIG. 1, the film forming chamber 10 is composed of an outer chamber 11 and an inner chamber 12 arranged in the outer chamber 11. In the outer chamber 11, the conductive base container 11-1 and the shield lid 11-2 form a processing space in a vacuum atmosphere. The inner chamber 12 constitutes the base container 12
-4 and a conductive plate 12-3 that is a lid, and the base case 12-4 and the perforated conductive plate 12-3 are electrically insulated by an insulator 12-8. ..

A large number of gas introduction holes 12 are formed in the conductive plate 12-3.
-5 is formed, and the processing gas introduced from the outside of the outer chamber 11 via the gas introduction pipe 15-2 is introduced into the inner chamber 12 from the gas emission hole 15-3 passing through the RF electrode 15. The conductive plate 12-3 is made of stainless steel, aluminum, or the like, has a large number of gas introduction holes 12-5 for introducing a processing gas into the film forming processing space of the inner chamber 12, and has a base container 12-4.
Are electrically insulated by the insulator 12-8 as described above. An RF electrode 15 is connected to the conductive plate 12-3 via a contact spring 15-1, and RF power energy is supplied from the conductive plate 12-3 into the inner chamber 12.

The base container 12-4 is the inner chamber 1
The second lower container is constructed, and the gas discharge port 13 is provided in the center of the lower container. The gas discharge port 13 is located immediately below the substrate electrode 14 installed at a predetermined distance from the inner bottom of the base body container 12-4. As a result, the introduced processing gas uniformly flows on the surface of the substrate 20 and is discharged to the gas discharge port 13 from the periphery thereof.

The processing gas from the gas discharge port 13 is discharged to the outside of the outer chamber 11 via a discharge pipe (not shown) provided in the outer chamber 11. With this configuration, the processing gas introduced from the gas introduction hole 12-5 of the conductive plate 12-3 is turned into plasma by the RF power energy applied from the RF electrode 15 via the conductive plate 12-3, and the surface of the substrate 20 is converted. The above chemical reaction uniformly acts on the surface of the substrate 20 to form a required film.

By repeating such a film forming process, film forming components are deposited on the inner wall of the inner chamber 12, and flakes separated from the film forming components become dust and the substrate 2 during the film forming process.
It adheres to the film formation surface of 0 and deteriorates the film quality. Therefore, after repeating the film forming process to some extent, a cleaning operation for removing the film forming components deposited on the wall surface of the inner chamber 12 is performed.

When this cleaning work is required, the shield lid 11-2 of the outer chamber 11 is removed together with the RF electrode 15 to clean the inside of the inner chamber 12. The inner chamber 12 can be detachably installed from the outer chamber 11. After removing the inner chamber 12 that has been used until then from the outer chamber 11, a new inner chamber is loaded into the outer chamber 11. The film forming process can be continued.

As a result, the film forming process can be continued even while the taken out inner chamber is being cleaned.
The operating rate of the film forming apparatus can be significantly improved. FIG. 3 is a vertical sectional view similar to FIG. 2 for explaining another embodiment of the film forming chamber in the film forming apparatus according to the present invention, and the same reference numerals correspond to the same parts. In the figure, an insulating plate 41 such as a quartz plate is used as the lid of the inner chamber 12, and the RF from the RF electrode 15 is passed through the insulating plate 41.
It is configured to apply energy into the inner chamber 12. In this embodiment, the inner chamber 1
The structure and operation are the same as those of the embodiment of FIG. 2 except that the insulating plate 41 is used instead of the conductive plate instead of the second cover.

By using this insulating plate 41, the RF electrode 15 is brought close to or in contact with this insulating plate 41 and R
By applying F power, the inner chamber 12
It is possible to form a uniform electric field distribution inside, suppress abnormal discharge, and perform more uniform film formation.

[0024]

As described above, according to the present invention,
The film forming chamber has a double structure including an outer chamber and an inner chamber, and a substrate electrode is arranged at a predetermined distance from the inner bottom of the inner chamber, and the substrate electrode is located at the center of the inner bottom and the substrate electrode. By providing a gas discharge port penetrating to the outer chamber side immediately below,
It is possible to limit the area where the film-forming substance adheres during the film-forming process to the inside of the inner chamber, and the cleaning of the inner chamber where the film-forming components are deposited and the disassembly cleaning are sufficient for cleaning only the inner chamber. It is not necessary to suspend the processing for a long time, the operation rate of the film forming apparatus can be remarkably improved, and the formed film thickness can be made uniform.

[Brief description of drawings]

FIG. 1 is a schematic plan view showing only a main part of a film forming apparatus relating to plasma CVD for explaining an overall structure of a film forming apparatus according to the present invention.

FIG. 2 is a vertical cross-sectional view illustrating one example of a film forming chamber in the film forming apparatus according to the present invention.

FIG. 3 is a vertical sectional view similar to FIG. 2, illustrating another embodiment of the film forming chamber in the film forming apparatus according to the present invention.

FIG. 4 is a schematic diagram illustrating a schematic structure of a conventional plasma CVD apparatus.

[Explanation of symbols]

 10 film forming chamber 11 outer chamber 12 inner chamber 13 gas outlet 14 substrate electrode 15 RF electrode 20 substrate

Front Page Continuation (72) Inventor Daiya Aoki 2-1-1 Honai, Yao-cho, Neguro-gun, Toyama Prefecture Kokusai Electric Co., Ltd. Toyama Plant (72) Inventor Fumio Muramatsu 2-1-1 Yanai-cho, Yagi-cho, Toyama Prefecture Country Toki Electric Co., Ltd. Toyama Plant (72) Inventor Tomohiko Takeda 2-chome, Yanai, Yao-cho, Niseji-gun, Toyama Prefecture Kokusai Electric Co., Ltd. Toyama Plant

Claims (2)

[Claims] 1. An outer chamber for holding a vacuum atmosphere space, and an airtight inner chamber fixed inside the outer chamber so as to form an independent film forming space in the vacuum atmosphere formed by the outer chamber. The film forming apparatus is characterized in that the inner chamber is provided with a high-frequency electrode or a DC voltage electrode necessary for exciting plasma discharge or a substitute member thereof, and a substrate electrode. 2. An outer chamber for holding a vacuum atmosphere space, and an airtight inner chamber fixed inside the outer chamber so as to form an independent film forming space in the vacuum atmosphere formed by the outer chamber. The film forming apparatus is characterized in that the inner chamber is provided with gas exhaust ports which are provided at four corners thereof and have uniform exhaust speeds and which are open to the outer chamber side.