JPS6052013A - Photo-cvd device - Google Patents

Abstract

PURPOSE:To keep the quantity of beams projected into a reaction vessel constant at all times by blowing a gas capable of removing a film formed to an optical introducing window against the window. CONSTITUTION:CF4 gas introduced into a film removing-gas reaction vessel 9 from a film removing-gas introducing port 8 is decomposed by high-frequency power fed from a high-frequency power supply 11, and reacts with a film shaped to a window 6 to form a gas component capable of removing the film. Gas pressure in the vicinity of the window 6 is kept at pressure lower than that in the film removing-gas reaction vessel 9 by the action of a film removing-gas discharge port 13, and the radicals of F formed in the vessel 9 are transported to a film removing-gas spray nozzle 12 and blown against the window 6. Accordingly, the film on the window 6 is removed by an etching reaction by the radicals of F.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to optical CVD (Chemical Vapor
Deposition) device.

[Prior art]

A conventional device of this type is shown in FIG. In the figure, 1 is a film forming reaction vessel, 2 is an inlet for a reaction gas for forming a film, 3 is an exhaust port for a film forming gas, 4 is a light source, 5 is a reflector, and 6 is a light source for directing light to the reaction vessel. The window 7 to be introduced into the sample is a sample.

Next, the operation will be explained. The gas introduced into the reaction vessel 1 through the film-forming gas inlet 2 undergoes a decomposition reaction due to the action of light from the light emitting source 4 and the reflecting plate 5, and as a result, a thin film is formed on the sample 7.

On the other hand, the remaining gas is exhausted from the exhaust port 3.

The conventional photo-CVD apparatus is configured as described above, and the light is not only exposed on the sample 7 but also on the wall of the reaction vessel 1 and the light introduction window 6.
A film is also formed on the sample 7, and the film formed on the light introduction window 6 reduces the light transmittance.
This had the disadvantage that it significantly inhibited the formation of the upper film.

[Summary of the invention]

This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and it is possible to form a film on the light introduction window by spraying a gas that can remove the film formed on the light introduction window. Light C that can prevent the formation of stable films.
The purpose is to provide a VD device.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. Second
The figure shows an optical CVD apparatus according to an embodiment of the present invention, and in the figure, the same reference numerals as in FIG. 1 indicate the same parts. Reference numeral 20 denotes an anti-fogging mechanism added in this embodiment. In this mechanism 20, a gas such as CF4 for removing the film formed on the light introduction window 6 is supplied to the film removal gas through the film removal gas inlet 8. The gas is introduced into the reaction vessel 9. The high frequency electrode 10 is for supplying electric power from the high frequency power source 11 to the gas in the container 9. Further, 12 is a blowing nozzle for blowing the gas generated in the reaction vessel 9 onto the light introduction window 6, and 13 is an exhaust port for the blown gas.

Next, the operation will be explained.

The CF4 gas introduced into the membrane removal gas reaction vessel 9 through the membrane removal gas inlet 8 is decomposed by high frequency power supplied from a high frequency power supply 11 via a high frequency electrode 10 to generate F radicals. That is, a gas component is generated that can react with the film formed on the window 6 and remove this film. Then, by the action of the membrane removal gas exhaust port 13, the window 6
If the gas pressure in the vicinity is kept lower than the gas pressure in the membrane removal gas reaction vessel 9, the F radicals generated in the vessel 9 will be transported to the membrane removal gas blowing nozzle 12, and the 6 will be sprayed.

As a result, the film formed on the window 6 is removed by an etching reaction caused by the F radicals. Thereby, the window 6 is maintained in a state in which no film is formed. On the other hand, the products of the ethoching reaction are discharged to the outside of the membrane forming reaction vessel 1 through the membrane removal gas exhaust port 13.

In addition, in the above embodiment, the gas was decomposed by applying high-frequency power to create a gas component capable of removing the film formed on the window, but the film-removing gas does not need to be decomposed by high-frequency power. Any gas that can remove the film may be used, and in this case, the high frequency electrode 10 and the reaction vessel 9 are unnecessary.

〔Effect of the invention〕

As described above, according to the present invention, since the light introduction window is sprayed with a gas capable of removing the crotch formed on the light introduction window, it is possible to prevent the formation of a film on the light introduction window, thereby preventing the reaction vessel from forming a film. The amount of light irradiated inside can be kept constant at all times, which has the effect of making it possible to form a stable film.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a conventional optical CVD apparatus, and FIG. 2 is a diagram showing an optical CVD apparatus according to an embodiment of the present invention. 1... Reaction container, 2... Film forming gas inlet, 3...
・Film forming gas exhaust port, 4... Light emitting source, 5... Reflector, 6... Light introduction window, 7... Sample, 20... Anti-fogging mechanism, 8... Film removing gas Introduction port, 9... Membrane removal gas reaction vessel, 10... High frequency electrode, 11... High frequency power source, 12... Nozzle for spraying film removal gas, 13...
・Membrane removal gas exhaust port. In the drawings, the same reference numerals indicate the same or equivalent parts. Figure 1 'l Figure 2

Claims (2)

[Claims] (1) An optical CVT (optical CVT) device that forms a film on a sample through a chemical vapor phase reaction using light, which includes a light introduction window for depositing the sample inside and a fogging that prevents the formation of a film on the light introduction window. Defense +l
[Optical CVr) device characterized by comprising: (2) The optical CVD according to claim 1, wherein the anti-fogging mechanism is equipped with a nozzle that sprays a gas onto the window that can remove a film formed on the light introduction window. Device.