JPS59225568A - Manufacture of thin film transistor matrix array - Google Patents

Abstract

PURPOSE:To remove generation of a short-circuit, and to enhance manufacturing yield of the title device by a method wherein gate electrodes directly under pin holes generated in gate insulating films and semiconductor films are removed by etching according to anodic electrolysis. CONSTITUTION:After gate electrodes 10 of NiCr films, and two layer films 12 of a gate insulating film and a semiconductor film are formed, the gate electrodes 10 are made as a bundle anode, immersed in an etching liquid, and the DC voltage of 2-10V is applied for 10-60sec using Ni as a cathode. After then, rinsing is performed sufficiently according to pure water to remove the etching liquid. When treatment is performed in such a way, the NiCr films at the parts having pin holes in the gate insulating films and the semiconductor films are removed. Accordingly, even when drain and source electrodes to be formed hereafter are provided, and although the pin holes exist, because the gate electrodes 10 have no pin hole part, the short-circuit is removed. Accordingly, manufacturing yield is enhanced sharply.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a method of manufacturing a thin film transistor matrix array used for driving each cell of a matrix type liquid crystal display device.

Background of the Technology FIG. 1 is a diagram for explaining a liquid crystal display tunnel using a glass substrate and a thin film transistor as a pixel switch, in which a shows a plan view and b shows a cross-sectional view.

In the figure, 1 is a glass substrate, 2 is a dirt pass line, lj:)' rain pass line, 4 is a dirt electrode connected to the K+F lotus line, 5 is a source electrode, and 6 is a transparent conductive film connected to the source electrode. 7 is a counter electrode made of a transparent conductive film, and 8 is a liquid crystal.

In FIG. 1, the dirt path line 2 and the drain path line 3 constitute the vertical lines and horizontal lines of the matrix.
The display section 6 is rectangular with a large area, and as shown in Figure b, forms a pair of electrodes of a liquid crystal channel together with a counter electrode 7, and a liquid crystal 8 is sealed between these electrodes. Then, when the drain and dirt electrodes are selected and a voltage is applied, the voltage is applied to the source electrode 5, which together with the selected drain and dirt electrodes constitute a thin film transistor, to the Q display section 6 and the counter electrode 7.
The alignment of the liquid crystal in between changes, and that part becomes transparent and appears white.

Prior Art and Problems There are the following four failure modes as causes of failure in the 1tri film transistor matrix array used in such liquid crystal displays and panels.

The first is a break in the dirt pass line 2, the second is a break in the drain pass line 3, the third is a short between the gate electrode 4 and the drain pass line 3, and the fourth is a short between the dirt electrode 4 and source electrode 5. It is short.

Among these, the first and second causes are missing pixels on the line, and the fourth
The cause of this is a display failure of one pixel, and the third cause is a failure mode of the entire panel. These first
, the second cause occurs during patterning,
It can be overcome by acquiring skills.

On the other hand, the third and fourth causes are short circuits due to pinholes, which can be reduced by changing the formation conditions of the insulating film and semiconductor film, etc., but especially in the third case, short circuits caused by pinholes can occur. This results in the entire pno-nine becoming defective, which is a major cause of reduced manufacturing yields for such arrays.

Furthermore, there is currently no remedy for such failures.

Purpose of the Invention In view of the above conventional problems, the present invention provides a method for manufacturing a thin film transistor matrix array, which can improve the manufacturing yield by relieving short-circuit defects caused by pinholes in the insulating film and semiconductor film in the thin film transistor matrix array. It is intended to be offered as an offering.

According to the present invention, in a thin film transistor matrix array consisting of a dirt electrode, a dirt insulating film, a semiconductor film, and source and drain electrodes, the dirt electrode portion directly under the pinhole that occurs in the semiconductor film and the dirt insulating film is removed. This is achieved by providing a method for manufacturing a thin film transistor matrix array, characterized in that the date pass line is removed by electrolytic etching using the date pass line as an anode.

Examples of the invention Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a diagram for explaining a method of manufacturing a thin film transistor matrix array according to the present invention. In the figure, 10 is a dirt electrode of NiCr film, 11 is n''a-
81: Drain electrode consisting of H/)l, 12 is S i
02 or S i , two-layer film of dirt insulating film using N4 and a-8i film of semiconductor film, 13 is n+a- only on top of 12
8i: Display part electrode made of a transparent conductive film connected to the source electrode of H/At, 14 is a 5IO of dart insulating film.
This figure shows an insulating film between the dart and the drain using 2. The upper part of the dirt electrode film 10 is entirely made of SiO except for the edge of the substrate.
2 covered with an insulating film.

In the manufacturing process of such a thin film transistor matrix array, the method of the present invention involves forming a gate electrode 10 and a two-layer film 12 of a dirt insulating film and a semiconductor film, and then using the dirt electrode 10 as a collective anode and applying H2O. , 3Qml:
H, PO4 (specific gravity 1.71) immersed in 70 m/etching solution, using Ni as the cathode, and applying a direct current of 2 to IOV'f.
Apply rlo~60 seconds. After that, thoroughly rinse with pure water to remove the etching solution, and then remove the etching solution from the edge of the substrate.
The dirt electrodes 10 that have been put together are separated one by one by etching using a resist.

By processing in this manner, NiCr is removed from portions of the dart insulating film and the semiconductor film where there are pinholes.

Therefore, even if the drain and source electrodes formed later are provided, even if there is a pinhole, there will be no short circuit because the dirt electrode 10 does not have that part. Therefore, manufacturing yield is greatly improved.

Also, the size of this pinhole is 0.5 μm compared to the size of a thin film transistor (for example, 20 μm x 200 μm).
Since it is sufficiently small, about φ, it has almost no effect on the characteristics of the thin film transistor.

Effects of the Invention As explained in detail above, the method for manufacturing a thin film transistor matrix array of the present invention prevents the occurrence of short circuits by removing the dirt electrodes directly under the pinholes that occur in the dirt insulating film and semiconductor film by anodic electrolytic etching. This has great effects in that it can prevent this and improve manufacturing yield.

[Brief explanation of drawings]

Figure 1 is a 4S diagram for explaining a liquid crystal display panel using a conventional thin film transistor matrix array.
FIG. 2 is a diagram for explaining a method of manufacturing a thin film transistor matrix play according to the present invention. In the drawings, 10 is a gate electrode, 11 is a drain electrode, 12 is a case-1 insulating film and a semiconductor film, 13 is a display electrode, and 14 is an insulating film between the dirt and the drain. Patent applicant Fujitsu Limited Patent agent Akira Aoki Patent attorney Kazuyuki Nishidate (1) Yukio Patent attorney Akira Yamaguchi (C1) (b)

Claims (1)

[Claims] 1. In a thin film transistor matrix array consisting of a dirt electrode, a dirt insulating film, a semiconductor film, and source and drain electrodes, electrolytic etching is performed on the dirt electrode part directly under the pinhole that occurs in the semiconductor film and dirt insulating film, using the cathode bus line as an anode. 1. A method for manufacturing a thin film transistor matrix array, the method comprising the step of removing the thin film transistor matrix.