JPS6056308A - Method of patterning transparent conductive electrode film - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a method for patterning a metal oxide transparent electrode film in a display device or the like.

(2) Background of the Technology Electronic numeric displays are widely used not only in industrial equipment, but also in pocket calculators, digital II'Jl meters, electronic wristwatches, and the like. Such displays use, for example, electroluminescent displays, which consist of a thin film of phosphor on a glass substrate, the phosphor and the front electrode being transparent. This electrode is generally called a transparent conductive electrode film, and the present invention relates to its patterning.

(3) Conventional technology and problems In conventional patterning of a transparent conductive film, a resist is applied directly onto the transparent conductive film, and the resist is exposed and developed to pattern the transparent conductive film and then the transparent conductive film is etched. However, with this method, when inspecting the pattern by visual inspection after etching, since the pattern is transparent, short circuits between patterns or open patterns (gaps such as holes), etc. may be detected. It has been experienced that visual inspection for defects is difficult.

(4) Purpose of the Invention The present invention addresses the above-mentioned conventional problems, and provides a transparent conductive film that facilitates pattern inspection during etching of a transparent conductive electrode film, and that does not affect the resistance value of the transparent conductive film in any way. The purpose is to provide a patterning method.

(5) Structure and object of the invention According to the present invention, in a method for patterning a transparent conductive electrode film for a display device formed on a transparent substrate, a metal thin film is entirely coated on the crotch of the transparent electrode. To provide a method for patterning a transparent conductive electrode film, which is characterized in that patterning is subsequently performed using a photoresist, the metal film and the transparent conductive film are sequentially etched, and after the photoresist is removed, the upper metal film is selectively etched. This is achieved by

(6) Examples of the invention Embodiments of the present invention will be explained in detail below with reference to the drawings.

In the present invention, NiCr, Ti+Ta, Mo,
Taking advantage of the fact that there are etching solutions and etching methods that have excellent selectivity between metals such as W and indium oxide, which constitutes the transparent conductive film, visual inspection can be performed using a 211 configuration of patterned metal/transparent conductive electrode. After inspection, the metal film is selectively etched away. A first embodiment of the present invention using NjCr as the metal is shown with reference to FIG.

A transparent conductive electrode film with an IIA thickness of 1000 mm, that is, a 1n203 (Sn) film 2 formed on a glass substrate 1 (first
Figure (a)), 500 metal films, namely NiCr films 3
is deposited by vacuum evaporation (or sputtering) (FIG. 1(b)).

After that, photosensitive resist II is removed.4. The pattern is formed by photolithography (which may be of a positive type or a negative type). The resist film 4 after pattern formation is shown in the plan view of FIG.

Then ceric ammonium nitrate ((Nh)2Ce
NiCr film 3 was formed using an aqueous solution containing (NO3)6), and In203 was formed using an aqueous solution containing ferric chloride (FeCP!, 3).
The (Sn) film 2 is sequentially etched, and the resist film 4 is subsequently removed. After that, visually inspect for shorts and opens and make corrections as necessary. This inspection can be carried out easily and reliably by visual inspection because of the presence of the yellow NtCr film 3.

After this inspection and repair, Ni was treated with ceric ammonium nitrate solution.
Selective etching is performed only on the Cr film 3 to obtain a pattern of a transparent conductive electrode film. NiCr etchant In2Q3 (
The effect on the resistance value (Sn) is that there is an increase of about 5% for 5 hours of immersion, and since the etching time for NiCr is about several tens of seconds, it was confirmed that there is no practical problem at all. .

Next, a second embodiment of the present invention using 1'a will be described. Similar to the previous example, 1000 transparent conductive electrode films, i.e. 1n203
A metal film of 500 layers, ie, a 1'a layer, is deposited on the (Sn) film by vacuum deposition. After patterning, the metal IQ (1
Perform etching (dry etching) of 'a>. Etching time is 50 seconds. Then, the above In2Q3
Etching is performed using a (Sn) etchant, and the resist is removed, visually inspected, and repaired. Since Ta is black-gray, visual inspection can be easily and reliably performed as in the case of the first embodiment.

Thereafter, Ta11R is removed by plasma etching under the above conditions, and patterning is completed. The effect of such gas plasma etching on the In2O3 (Sn) resistance value is only about a 20% increase compared to etching for 10 minutes, and since the etching time for Ta is about 50 seconds, there is a slight increase in the resistance value of In2O3 (Sn). Even if there is overetching, there is almost no practical problem. The trial etching of the second embodiment has the advantage that etching is performed in accordance with the resist pattern without site etching.

(7) Effects of the Invention As explained in detail above, according to the present invention, pattern inspection of transparent conductive electrode films used in display devices is facilitated, and therefore inspection time can be significantly shortened. .

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the steps of carrying out the method of the present invention, and FIG. 2 is a plan view showing the pattern of the resist film obtained by the steps shown in FIG. ■-Glass substrate, 2-Transparent conductive electrode film (In203(Sn)), 3-Gold 1! Film (NiCr
), 4- resist film

Claims (1)

[Claims] In a method of patterning a transparent conductive electrode film for a display device formed on a transparent substrate, a metal thin film is coated on the entire surface of the transparent electrode, and then patterning is performed using a photoresist to form a pattern of the metal film and the transparent conductive electrode film. 1. A method for patterning a transparent conductive electrode film, which comprises sequentially etching the photoresist and selectively etching the upper metal film after removing the photoresist.