JPH0216529A - Method of lowering resistance of transparent electrode - Google Patents

Abstract

PURPOSE:To inexpensively form transparent electrodes without requiring a special aligner for forming the transparent electrodes as metallic wirings by selectively coating a metal on the patterned transparent electrodes, coating the surface of an electrode substrate with a negative type photoresist and stripping the photoresist, then etching away the exposed metal. CONSTITUTION:The patterned transparent electrodes 2 are formed on a glass substrate 1 and only the surface of the transparent electrodes is selectively coated with the metal 3 by chemical plating or electroplating. The surface of the transparent electrode substrate coated with the metal is coated with the negative type photoresist 4. The substrate is then irradiated with UV rays from the rear side of the substrate and the photoresist on the metal is stripped by development. The exposed metal is etched away and the remaining photoresist is completely stripped. The selective metallization of only the two side edges of the transparent electrodes is enabled in this way without requiring a special photomask.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for reducing the resistance of a transparent electrode formed on a glass substrate of a liquid crystal panel, an EL panel, etc. by metal assist.

[Prior Art a] With the increase in pattern density and drive frequency of display elements, it is increasingly desired to lower the resistance of transparent electrodes. Through improvements in various materials and film-forming methods, transparent electrodes can be made with 2 x 1 (f
``Although it is now possible to mass-produce resistances around Ω・α, the demand for lower resistance is even stricter, and it is 10% lower than this.
It is necessary to do the following.

For this purpose, attempts have been made to overlap metal wiring with transparent electrodes. Generally, a metal (Or, Ti, Ni-0r, Ni, etc.) is placed on a patterned transparent electrode substrate.
A method has been used to cover the entire surface and leave some metal by photo method, but it is extremely difficult to arrange metal with a line width of several microns or less without disconnection, and if a large width is left, the aperture ratio will be reduced. This has the disadvantage that the display becomes dark as a whole.

[Problems to be Solved by the Invention] The present invention provides a method for solving such drawbacks in metal wiring, and considers selectively metalizing only the edges of both sides of a transparent electrode, and The purpose is to obtain this without requiring a special photomask.

[Means for Solving the Problems] A method for reducing the resistance of a transparent electrode of the present invention includes (a) forming a patterned transparent electrode on a glass substrate in a method for reducing the resistance of a transparent electrode by coating with a metal; Step Cb) Step of selectively coating metal only on the transparent electrode by chemical plating or electroplating (c) Step of coating the surface of the metal-coated transparent electrode substrate with a negative photoresist (d) Step of coating the surface of the metal-coated transparent electrode substrate from the back side of the substrate step (t) of stripping the photoresist on the metal by irradiating ultraviolet rays and developing; (t) a step of etching away the exposed metal; and (f) stripping all the remaining photoresist. At least the steps (a) to (f) It is characterized by containing.

The present invention will be explained using FIG.

In FIG. 1(a), reference numeral 1 denotes a glass substrate, which is made of soda glass, borosilicate glass, quartz glass, etc., and is subjected to passivation treatment such as Sin, At, 0°, etc., as required. 2 is a transparent electrode;
ZnO, At, O.

etc. are used, but to date, TO has the lowest resistance, and the MIN value is 2 X i O-'Ωm. It is coated by means of sputtering, vapor deposition, PVD, etc., and is patterned as shown in FIG. 1 through a predetermined photo process.

Next, in step Cb), 3 is a metal and is formed by selectively coating the transparent electrode. electroplating,
Chemical plating is a means for this purpose, and chemical plating is a particularly effective means. A method of selectively metallizing a transparent electrode by chemical plating is a method already known by the present inventors. N1-P or N i -P / A u , M
i-P/Ou, M i-P/Ni
-B*Ni-P/Mi-B/Au, etc. Single metal or multilayer plating can be used. In the case of multilayer plating, the second and subsequent layers may be applied after step (f). It is also possible to add adhesion improving means such as heat treatment, if necessary.

Next, in step (c), 4 is a photoresist, and only a negative type can be applied, and a spin code method is used.

It is coated by a roll foot method or the like.

Next, step (d) shows a step of irradiating UV light from the back side of the substrate and an original image step. For the purposes of the present invention, it is more desirable to use non-parallel light.The next step (e) is the etching of the exposed metal, and it is necessary to select a method that has a large etching selectivity with respect to the transparent electrode.

Next, step (f) is a resist stripping step, and through this step, an electrode in which both edges of the transparent electrode are metallized is completed.

[Example] S10. A 1 to 2 m thick soda glass coated with a passivation coating was coated with 1500X TO by sputtering and patterned using a predetermined method. ...Step (a) Sheet resistance was 15Ω/hole.

Next, the substrate was exposed to a mixed activator, Hi9101B manufactured by Hitachi Chemical Co., Ltd., for 5 minutes.
It was soaked for a minute and then washed with water. Next, soooXmt-P plating was performed using electroless N1-P plating S-680 manufactured by Kanigen Co., Ltd. Next, 2μ of electroless Mi-B plating (Nyclad 704 manufactured by Okuno Pharmaceutical Co., Ltd.) was plated...Step (b) Next, a negative photoresist OMR-85 manufactured by Tokyo Ohka Chemical Co., Ltd. was applied to the electrode surface using a roll coater. 1μ was applied. ...
...Step (c) Next, exposure and development was performed using ultraviolet rays from the back side of the substrate.

...Step (d) Next, N1-B and N1-P were etched away using the etching solution remaining from HNO,,H,304,01(,0OOH. ...Step (d) Next, the remaining photoresist was removed. Step (f) Used as a body electrode.

[Brief explanation of the drawing]

FIG. 1 (a) to (f-) are cross-sectional views of the substrate. 1...Glass substrate 2...Transparent electrode 3... Plated metal 4...
...Negative photoresist) l'! , the process flow of the present invention [the effect code of the invention]

Claims (1)

[Claims] A method for lowering the resistance of a transparent electrode by metal coating, which includes: (a) forming a patterned transparent electrode on a glass substrate; (b) selectively applying a chemical coating only on the transparent electrode; (c) Covering the surface of the metal-coated transparent electrode substrate with a negative photoresist (d) Applying ultraviolet rays from the back side of the substrate and developing the photoresist on the metal. A method for reducing the resistance of a transparent electrode, comprising at least the steps (a) to (f) of stripping (e) etching away the exposed metal and (f) stripping all the remaining photoresist.