JPH05152214A - Cvd device - Google Patents

Abstract

PURPOSE:To form a film on the surface of a light-transmitting glass base body under the same conditions without being attached on the internal surfaces of a pipe and an exhauster by the residue of a raw material gas and the reaction product of a reaction gas, and to obtain uniform optical characteristics. CONSTITUTION:The internal temperature of a pipe 23 connecting a reactor 23 and an exhauster 29 is set at the same temperature as the reactor 23 or higher. A heater 30 is arranged on the external surface of the pipe 28 in order to keep the internal temperature of the pipe 28.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to improvements in CVD equipment.

[0002]

2. Description of the Related Art Conventionally, an optical thin film is formed on the surface of an optical component by using a vacuum evaporation method or a sputtering method. This optical thin film has a single-layer or multi-layer structure. The film material used to form each of these layers is, for example, titanium oxide (TiO ₂ ) for the high refractive index layer,
Zinc sulfide (ZnS) or the like, and for the low refractive index layer, silicon dioxide (SiO ₂ ), magnesium fluoride (MgF ₂ ) or the like,
For the intermediate refractive index layer, aluminum oxide (Al2O
3), cerium fluoride (CeF3) and the like are common.

By the way, when an optical thin film having a multi-layer structure is formed on the surface of an optical component made of a translucent glass substrate by a vacuum vapor deposition method or a sputtering method, the adhesion of the film to the substrate is low and the temperature is 300 ° C. or higher. In use at high temperature,
In many cases, the optical properties of the film deviate significantly from the initial properties at the time of film formation, making it unusable. In addition, the operating temperature is 500
If the temperature is raised to or above 0 ° C. and used for a long time, the film will be destroyed, and in the extreme case, the entire film will peel off from the substrate. Further, even when used under a high temperature and high humidity condition where the temperature is 60 ° C. or higher and the humidity is 90% or higher, there is a great drawback in that the film becomes cloudy and peels.

Therefore, conventionally, a single layer or a multilayer film is formed on the surface of the transparent glass substrate by the CVD method. In a CVD apparatus for forming a film using a CVD method, as shown in FIG. 2, a source gas is fed from a source gas container 1 to a reaction container 2 and a reaction gas is fed from a reaction gas container 3 to transmit a transparent glass. A film is formed on the surface of the substrate.

[0005]

SUMMARY OF THE INVENTION Conventional CVD described above
According to the apparatus, when the raw material 4 is liquid or solid at room temperature and atmospheric pressure, when the raw material gas is fed into the reactor 2, the raw material 4 is heated and turned into a gas, and the surface of the translucent glass substrate is fed. The raw material gas that forms a film on the reactor 2 and is exhausted in the reactor 2 together with the gas of the reaction product is exhausted by an exhaust device 6 that is connected to the reactor 2 through a pipe 5. By the way, the rest of the raw material gas and the reaction product gas are cooled when being exhausted from the pipe 5 through the exhaust device 6, and the rest of the raw material gas and the reaction product of the reaction gas become liquid or solid. Exhaust device 6
Attached to the inner surface of the reactor, the pressure inside the reactor 2 changes, and a film cannot be formed on the surface of the translucent glass substrate at a predetermined pressure. For this reason, there is a drawback that not only the maintenance of the pipe 5 and the exhaust device 6 becomes difficult, but also the film characteristics vary, and desired optical characteristics cannot be obtained.

The present invention has been made in view of the above points, and by the relatively simple device, the rest of the raw material gas and the gas of the reaction product do not adhere to the inner surfaces of the pipe and the exhaust device. An object of the present invention is to provide a CVD apparatus capable of forming a film on the surface of a translucent glass substrate under predetermined conditions and obtaining desired optical characteristics.

[0007]

In order to solve the above problems, the present invention has the following constitution. That is, in claim 1, a CVD apparatus is configured to have a reactor for feeding a raw material gas and a reaction gas to form a film on a sample, and an exhaust device connected to the reactor via a pipe. The inner surface temperature of the pipe is set to be equal to or higher than the temperature of the reaction vessel. In the second aspect, the heater is arranged on the outer surface of the pipe connected between the reactor and the exhaust device to constitute the CVD device.

[0008]

According to the CVD apparatus having the above-mentioned structure, when the remaining raw material gas and the gas of the reaction product are exhausted through the pipe by the exhaust device, they are not cooled to become liquid or solid, and the light is transmitted at a predetermined pressure. A film can be formed on the surface of the transparent glass substrate, the maintenance of the exhaust system is facilitated, and an optical component having desired optical characteristics can be obtained.

[0009]

[Embodiment 1] The present invention will be described in detail below with reference to an embodiment. In FIG. 1, 21 is a source gas container, which is a CV
The D substance 22 such as tetraethoxysilane, tetraisopropoxytitanium, or pentamethoxytantalum is stored. These raw materials are liquid, liquid and solid at room temperature and atmospheric pressure, respectively. For example, tetraethoxysilane has an internal temperature of 40 ° C., tetraisopropoxy titanium has an internal temperature of 60 ° C., and pentamethoxytantalum has an internal temperature of 1 ° C., for example.
Insulate by heating to 40 ° C.

22 is a reactor, 24 is an inlet, 2
Reference numeral 5 indicates a discharge port. Reference numeral 26 is a translucent glass substrate arranged inside the reactor 23, and 27 is a heating mechanism for heating the translucent glass substrate 26. The internal temperature of the reactor 23 is set to, for example, about 500 ° C. 28 is a pipe connected to the outlet 25 of the reactor 23.

As the heating mechanism 27, for example, the reactor 23
The heater 30 is arranged on the outer surface of the pipe 28 connected between the exhaust pipe 29 and the exhaust device 29. The temperature of the outer surface of the pipe 28 is set to about 140 ° C., for example. Reference numeral 31 is a reaction gas container for sending the reaction gas to the reactor 23.

[0012]

As described above, according to the present invention, the internal temperature of the pipe connecting the reactor and the exhaust device is equal to or higher than the internal temperature of the raw material container. In addition, the residue of the raw material gas and the gas of the reaction product do not adhere to each other, so that the maintenance of the exhaust system is facilitated and an optical component having optical characteristics can be obtained. Further, the temperature of the inner surface of the pipe has an effect that it can be easily configured by disposing a heater on the outer surface of the pipe.

[Brief description of drawings]

FIG. 1 is a schematic view of a CVD apparatus of the present invention.

FIG. 2 is a schematic view of a conventional CVD apparatus.

[Explanation of symbols]

 21 Raw Material Gas Container 23 Reactor 24 Inlet 25 Discharge 26 Glass Substrate 27 Heating Mechanism 28 Pipe 29 Exhaust Device 30 Heater 31 Reaction Gas Container

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hiroshi Kawai 11-11 Iriyama-cho, Gyoda-shi, Saitama Iwasaki Electric Co., Ltd. Saitama Factory

Claims (2)

[Claims] 1. A raw material gas and a reaction gas in a CVD apparatus for forming a film by reacting a liquid or solid substance as a raw material at room temperature and atmospheric pressure with a gasified substance and a gas substance at room temperature and atmospheric pressure. And a reactor for forming a film on the sample,
A CVD apparatus comprising: an exhaust device connected to the reactor via a pipe, and an inner surface temperature of the pipe being equal to or higher than a temperature of a reaction tank. 2. The CVD apparatus according to claim 1, wherein a heater is arranged on the outer surface of a pipe connected between the reactor and the exhaust device.