JPS62162628A - Production of amorphous thin film - Google Patents

Abstract

PURPOSE:To obtain the titled B2O3-based thin film having high uniformity and transparency, e.g. a borosilicate glass, etc., by applying an organometallic compound containing a boron compound to a substrate in a specific atmosphere and baking and oxidizing the coating layer. CONSTITUTION:An organometallic compound containing a boron compound can be produced e.g. by adding B-triisopropoxide to an alcoholic aqueous solution of a partially hydrolyzed Si-tetraethoxide. The obtained compound is applied to a cleaned surface of a substrate such as glass in an atmosphere composed of an inert gas such as N2, He, Ar, etc., and having a relative humidity of <=40%. The coating layer is oxidized and calcined e.g. in air to obtain the titled transparent thin film.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing an amorphous thin film using an organometallic compound, and particularly to a method for manufacturing a borosilicate glass thin film.

[Conventional technology]

Organometallic compounds (e.g. 5i(OC2H5)4-C!2
A method is known in which a 5i02 thin film is formed on a substrate by coating a substrate with a H50H-H2OHCI mixture and then baking it. (For example, the science of glass amorphous, inner circle However, according to the above conventional method of manufacturing amorphous thin film, 5i02-
When attempting to create a thin film with a composition containing boron, such as B203+AJ203-B203 thin film, there was a problem in that a non-uniform part (cloudy part) was created in the coated film of the organometallic compound, making it impossible to obtain a homogeneous amorphous thin film. .

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides a method for producing an amorphous thin film in which an organic metal compound is applied to a substrate and then fired and oxidized to form an amorphous thin film on the surface of the substrate. This is applied to the substrate in an atmosphere with a relative humidity of tIo% or less.

The atmosphere can be created by, for example, flowing a low-humidity gas (preferably a dry gas) into the process of applying the organometallic compound.

The above low humidity gas is N 2 + He + Ne
+ If an inert gas such as Ar is used, organometallic compounds whose oxidation number may change (for example, 5n ((35
Even when H702)2) is contained, a stable coating film can be formed, which is preferable.

The atmosphere must have a relative humidity of 40% or less; if the relative humidity exceeds 110%, boron compounds (such as boron alflate and its reactants) will generate hydroxides, so organometallic compounds The coating film cannot be maintained stably.

The lower the relative humidity of the atmosphere, the better, for example, 2Q% relative humidity.
The following are preferred.

[For production]

The present invention provides S1 tetraethoxide, B triisopropoxide I C2H50HIH2 by the conventional method.
When attempting to create a 5i02-B203-based thin film using a 5i02-B203 mixed solution, the heterogeneity that occurs on the organometallic compound coating film is caused by moisture in the working atmosphere during coating film formation entering the coating film. This was done in view of the fact that it is based on (OH)3.

According to the present invention, since the humidity in the atmosphere is low, organometallic compounds (boron alkoxide, reaction products of boron alkoxide and silicon alkoxide, etc.) in the coating film do not react with moisture to generate heterogeneous substances. do not have.

〔Example〕

Si tetraethoxide and B triisopropoxide 5
When it becomes i02 and B2O3, the molar ratio is ♂O:20
Weigh each so that To the weighed S1 tetraethoxide, 5 times the molar ratio of ethanol and 6 times the molar ratio of water (+wt% HNO3 solution was used) were added and refluxed at about 70"C for 4 hours. By the above reflux, Si The tetraethoxide is in a state where a hydrolysis reaction has occurred to some extent.Then, the previously weighed B is added to the refluxed solution.
After the triisopropoxide was added dropwise, refluxing was continued for an additional hour at about 70'C. An equal amount (same volume) of ethyl alcohol was added to the above solution in which 5i-0-B bonds were thought to have been formed to some extent to prepare a coating solution. This coating solution was placed in a dry box completely replaced with N2 (relative humidity I
0%), a previously cleaned glass substrate was immersed in the coating solution, then pulled up, and the solution was applied onto the glass substrate. After coating, the glass substrate with the coated film was kept in a dry box and sufficiently dried, and then taken out from the dry box and baked in the air at 11° C. for 11 minutes. As a result, the crotch was a completely transparent and homogeneous amorphous thin film with a thickness of about 100 nm.

After further firing at 700'C for 70 minutes, a glass A'7N without bores was obtained.

〔Effect of the invention〕

According to the present invention, it is possible to create a uniform 203-based thin film, which was previously impossible, as is clear from the examples.

Claims (5)

[Claims] (1) In a method for manufacturing an amorphous thin film in which an organic metal compound is applied to a substrate and then fired and oxidized to form an amorphous thin film on the surface of the substrate, a compound containing a boron compound is used as the organic metal compound, and this is A method for producing an amorphous thin film, the method comprising coating a substrate in an atmosphere with a humidity of 40% or less. (2) The method for producing an amorphous thin film according to claim 1, wherein the atmosphere is achieved by introducing a dry gas. (3) The method for producing an amorphous thin film according to claim 1 or 2, wherein the organometallic compound is a mixture of boron alkoxide and silicon alkoxide. (4) The method for producing an amorphous thin film according to claim 2, wherein the drying gas is an inert gas. (5) The method for producing an amorphous thin film according to any one of claims 1 to 3, wherein the atmosphere has a relative humidity of 20% or less.