JPS60212220A - Photochemical reaction apparatus - Google Patents

Abstract

PURPOSE:To prevent ultraviolet rays from receiving the inhibition of transmission by preventing the accumulation of a reaction product to an ultraviolet ray pervious window, by forming the ultraviolet ray pervious window in a reaction vessel from a cooling mechanism or cooling the same in integral manner to the cooling mechanism. CONSTITUTION:Photo-reactive gas is supplied into a reaction vessel having an ultraviolet ray pervious window 14 by gas supply and exhaust mechanisms 11, 12 and a substrate 14 being an article to be treated is irradiated with ultraviolet rays from a light source 3 from the outside of the reaction vessel through the pervious window 14. In this photochemical reaction apparatus, the pervious window 14 is formed of cooling mechanisms 14a, 14b or constituted so as to be integrated with said cooling mechanisms. By this simple structure, no reaction product is accumulated to the ultraviolet ray pervious window and the transmission of ultraviolet rays is not interrupted.

Description

[Detailed description of the invention] The present invention relates to a photochemical reaction device.

Recently, research has been conducted into methods for forming thin films of amorphous silicon used in photosensitive drums of electronic copying machines, solar cells, and the like. On the other hand, vapor deposition methods are also used to form various types of insulating films and protective films, and various vapor deposition methods have been proposed depending on the application. It has the advantage of being extremely fast and capable of forming a uniform coating even over a large area, and has recently attracted particular attention.

In conventional chemical vapor deposition or deposition methods that utilize photochemical reactions, a substrate is placed inside a reactor that has a window that allows ultraviolet rays to pass through.
This method photochemically reacts the gas with an ultraviolet light source and vaporizes or deposits the reaction product on the substrate, and has the above-mentioned great advantages, but on the other hand, the reaction product also vaporizes or deposits on the transparent window of the container. It has been found that there is a drawback in that it greatly impedes the transmission of ultraviolet rays.

For this reason, in the past, vapor deposition or deposition on the transmission window was suppressed by applying oil to the transmission window or flowing an inert gas such as argon. However, although applying oil makes it easier to remove the accumulated reaction products, it has little effect on preventing the accumulation, and the nozzle for inert gas must be arranged so that the ultraviolet rays are not broken. It is difficult to uniformly spray the windows, and these measures have not been able to achieve sufficient effects.

Therefore, the present invention was completed by applying the fact that photochemical reactions are significantly suppressed at low temperatures, and has a simple structure that prevents products from accumulating on the ultraviolet-transmitting window and inhibits the transmission of ultraviolet rays. The purpose of this invention is to provide a photochemical reaction device that does not cause any damage. The structure consists of a reaction vessel having a window for transmitting ultraviolet rays, a gas supply/exhaust mechanism that supplies a photoreactive gas into the reaction vessel, and a substrate to be processed that is irradiated from outside the reaction vessel through the window. The present invention is a photochemical reaction device including an ultraviolet light source, and the transmission window is comprised of a cooling mechanism or is integrated with the cooling mechanism.

The present invention will be specifically described below based on embodiments shown in the drawings.

In FIG. 1, a reaction vessel 1 has a photoreactive gas introduction hole 1.
1 and an exhaust hole 12 connected to a pressure reducing device, and a substrate support stand 15 made of quartz glass is arranged in the center of the interior so as to be movable up and down. The upper surface is provided with an ultraviolet light transmitting window 14 made of quartz glass, and a lamp body 2 is integrally connected to the upper part of the window 14, and an ultraviolet lamp, which is an ultraviolet light source, is connected to the ceiling through a reflective member 21. 5 are arranged in parallel. Here, the ultraviolet lamp 5 is an AC lighting low-pressure mercury lamp with a tube diameter of 18mm, a lighting start voltage of 550cm, a lighting voltage of 90V, and a current of 5N, but is not limited to this, and is an electrodeless lamp. It may be a device or a plasma generator, and the folds may be of any type as long as they generate a predetermined amount of ultraviolet light. Further, if necessary, the inside of the lamp body 2 can be made to flow with gas or to be filled with nitrogen.

A sub-temperature regulator (#- not shown) is attached to the substrate support stand 13, and the substrate 4 supported by this is an alumina plate having an outer diameter of 160 m and is heated to about 150C. Note that this substrate support stand 15 can be made rotatable like a turntable or movable within the reaction vessel 1, so that a large number of substrates 4 can be efficiently processed by loading and unloading the substrates 4 with a transport mechanism. . A mixed gas consisting of argon as a carrier gas, mercury gas as a photosensitizer, and silicon tetrahydride as a decomposition vaporization gas is supplied from the introduction hole 11 into the reaction vessel 1. When using reactive gases, it is preferable to provide a plurality of introduction holes 11 to introduce each gas individually and mix them within the reaction vessel 1. It is preferable that a temperature regulator is provided in this introduction hole 11 to enhance the chemical reaction in which each gas is adjusted to an optimum temperature.

Next, the structure of the transmission window 14 will be explained. In this embodiment, the transmission window 14 is made of a hollow plate, and an inlet 14a and an outlet 14b are provided at both ends, and the inside thereof is cooled for gas or liquid. Allows the medium to pass through. Therefore, the transmission window 14 itself constitutes a cooling mechanism, and the cooling medium is selected from pure water, liquid nitrogen, or the like, which does not inhibit the transmission of ultraviolet rays. Figure 2 shows an example in which the hollow member has two layers, but this means that in order to cool the transmission window 14 to about 0 layers, a cooling medium such as liquid nitrogen must be used. I want to use less. Therefore, the antifreeze solution is passed in the upper layer near the lamp 6 to block the heat from the lamp 6 and to reduce the transfer of heat to the liquid nitrogen flowing in the lower layer, thereby reducing the amount of liquid nitrogen required. Further, in FIG. 5, a pipe 15 made of an ultraviolet-transparent material is fixed to the surface of the transmission window 14, and a gas or liquid cooling medium, which is also transparent to ultraviolet light, passes through the pipe 15. Therefore, the cooling mechanism and the transmission window are integrated, and the transmission window 14 is thereby cooled.

In the above apparatus, the pressure inside the reaction vessel 1 is reduced and the ultraviolet lamp 6 is turned on. Then, from the introduction hole 11, argon of 5■Hg, silicon tetrahydride of 3wHg,
Mercury vapor of be done. At this time, a portion of the photoreactive gas rises and moves toward the transmission window 14, but since the transmission window 14 is cooled, decomposition of silicon tetrahydride 5 in the vicinity is suppressed. In particular, if the transmission window 14 is cooled down to about -30°C using liquid nitrogen or the like as a cooling medium, it will hardly be photodecomposed, so even if it is operated for a long time, the transmission window 14 will remain
4. Does not accumulate and does not become cloudy.

Also, cooling with cooling water has a large effect and is not overwhelming, but even if a small amount accumulates, its adhesion is weak and can be easily wiped off.

As explained above, in the present invention, the transmission window is composed of a cooling mechanism or is cooled integrally with the cooling mechanism, so that photochemical reactions are suppressed in this vicinity, and no products are deposited. Therefore, according to the present invention, it is possible to provide a photochemical reaction device that has a simple structure, does not deposit products on the ultraviolet light transmission window, and does not inhibit the transmission of ultraviolet light.

[Brief explanation of drawings]

FIGS. 1, 2, and 6 are cross-sectional views of a ray implementing the present invention. 1...Reaction vessel 2...Lamp 6...Ultraviolet rung 4...Substrate 14...Transmission window 15...Pipe applicant Ushio Inc. representative Patent attorney Toranosuke Tahara procedural amendment ( (Voluntary initiative) August 10, 1980 Manabu Shiga, Commissioner of the Patent Office1, Indication of the case 1982 Patent Application No. 675132, Title of the invention Photochemical reaction device 3, Relationship to the person making the amendment case Representative of the patent applicant Inuzou Yumoto 4, Agent Name (8411) Patent Attorney 1) Toranosuke Hara 5,
Date of amendment order 6, Number of inventions to be increased by the amendment N/A 7, Detailed explanation of the invention in the specification subject to amendment 8, Contents of the amendment As shown in the attached sheet, "..." on page 7, line 13 of the specification lights up. "However, the photochemical reaction may be caused under normal pressure without reducing the pressure inside the reaction vessel l." is added. that's all

Claims (1)

[Scope of Claims] 1. A reaction vessel having a window for transmitting ultraviolet rays, a gas supply/exhaust mechanism for supplying a photoreactive gas into the reaction vessel, and a gas supply/discharge mechanism for supplying a photoreactive gas into the reaction vessel from outside the reaction vessel through the window for transmitting ultraviolet rays onto a substrate as an object to be processed. 1. A photochemical reaction device comprising: an ultraviolet light source for irradiating ultraviolet light, wherein the transmission window comprises a cooling mechanism or is integrated with the cooling mechanism. 2. The photochemical reaction device according to claim 1, wherein the transmission window is made of a hollow member, through which a cooling medium that transmits ultraviolet rays passes. Place. The photochemical reaction device according to claim 2, wherein the hollow member is multilayered. 4. A hollow member such as a pipe made of an ultraviolet-transmitting material is fixed to the surface of the transparent window, and a cooling medium that transmits ultraviolet rays passes through the inside thereof. photochemical reaction device.