JPS6251904B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a transparent electrode pattern using tin oxide, which has acid resistance and alkali resistance, and allows tin oxide, which has strong chemical resistance, to be easily formed into a predetermined pattern. This is how it was done.

Transparent electrodes conventionally used in liquid crystal displays and the like are mainly composed of indium oxide containing a small amount of tin. However, this method of using indium oxide as a transparent electrode has the disadvantage that when the device fabrication process involves many chemical treatments, the indium oxide is immersed in acids and alkalis, resulting in increased resistance. have.

On the other hand, tin oxide, which is also used as a transparent electrode, has excellent chemical resistance, so it has great utility as a transparent electrode in devices that involve many chemical treatments in the manufacturing process. Conventionally, a known method for forming tin oxide into a predetermined pattern is to reduce tin oxide to tin using zinc powder and then etching it with acid, particularly dilute hydrochloric acid.

Hereinafter, the conventional method will be explained with reference to FIG. 1. First, as shown in FIG. 1a, a glass insulating substrate 1 is
The tin oxide film 2 formed above is patterned with a photoresist 3, and then, as shown in FIG. The tin oxide film 2 is reduced by hydrogen generated when the zinc powder 4 and hydrochloric acid react to form a tin film 5 as shown in FIG. The tin film 5 thus formed is removed by etching with hydrochloric acid, and finally the photoresist 3 is removed to obtain a tin oxide film 2 formed in a predetermined pattern.

However, in this conventional method, it is necessary to make the zinc powder uniform in particle size and apply it evenly without damaging the photoresist on the tin oxide film, making it difficult to form a pattern of several tens of micrometers. If the thickness exceeds 1000 Å, it has many drawbacks, such as the reduction of tin oxide by hydrogen generated by the reaction between zinc and hydrochloric acid, which makes it difficult to penetrate into the interior.

The present invention eliminates these conventional drawbacks and reduces the number of
The present invention provides a method for forming a transparent electrode pattern in which a 10 μm pattern can be easily obtained and can be used even when the tin oxide film is thick. After forming the tin film, the tin film is etched to form a predetermined electrode pattern, and then the patterned tin film is oxidized in oxygen plasma.

In addition, in the present invention, the purpose of doping antimony into tin oxide is to lower the resistance of the tin oxide film finally obtained. Specifically, when forming the tin film, antimony is doped at the same time. Alternatively, a tin film can be formed using an antimony-doped sputter.

Hereinafter, one embodiment of the present invention will be specifically described with reference to the drawings.

Figures 2a, b, and c show each step of the present invention. First, a tin film containing a small amount of antimony is deposited on a glass insulating substrate 1 by vacuum evaporation or by sputtering in an argon atmosphere doped with antimony. 5 is formed, and a predetermined patterning is performed thereon using a photoresist 3 as shown in FIG. 2a. Next, the substrate 1 thus prepared is immersed in an etching solution diluted with water and hydrochloric acid at a ratio of 1:1 to etch the tin film 5, and then unnecessary photoresist is removed. (Figure 2b) The etching solution used at this time has an etching speed of approximately
This value is about 50 Å/sec, and this value is affected by the number of substrates to be etched and the thickness of the tin film, but the advantage over conventional methods is that by adjusting the time and changing the etching solution concentration, It is possible to form a tin film with a predetermined pattern without unevenness.
In the conventional method, the amount of hydrogen generated by the reaction with zinc powder changes as the concentration of hydrochloric acid changes, making it impossible to sufficiently reduce tin oxide. It can be uneven.

Next, the tin film 5 thus formed into a predetermined electrode pattern is oxidized by oxygen plasma with the substrate 1 placed on the anode side to form a tin oxide film 2 on the glass substrate 1. In this way, a tin oxide film having a desired electrode pattern as shown in FIG. 2c can be formed.

As is clear from the above description, since the present invention etches tin with hydrochloric acid without patterning tin oxide, which has strong chemical resistance, patterning can be easily and accurately performed. Moreover, since the present invention specifically oxidizes tin in oxygen plasma,
It is possible to form a thick tin oxide film with a thickness of about 1000 to 2000 Å with low resistance, which makes it possible to form patterns of several tens of μm and a film thickness of 1000 Å, which was impossible with conventional methods.
A very excellent effect can be obtained in that it is possible to form a tin oxide film with a thickness of Å or more.

[Brief explanation of the drawing]

FIGS. 1A, 1B, 1D, and 1D are sectional views showing each step of a conventional method for forming a transparent electrode pattern, and FIGS. 2A, 2B, and 2C are sectional views showing each step of the present invention. 1...Glass insulating substrate, 2...Tin oxide film, 3...
...Photoresist, 5...Tin film.

Claims (1)

[Claims] 1 After forming a tin film containing antimony on a glass insulating substrate using a vapor deposition method or a sputtering method, the tin film is formed into a predetermined electrode pattern by etching, and then this tin film is oxidized in oxygen plasma. A method for forming a transparent electrode pattern, characterized by converting the tin oxide into tin oxide.