JPH05224234A - Thin-film transistor substrate - Google Patents

Abstract

PURPOSE:To eliminate the wiring defects of the thin-film transistor(TFT) substrate and to improve yield. CONSTITUTION:The intersected point parts of the scanning electrode wirings 2 and signal electrode wirings 4 of the TFT substrate are divided into >=2 pieces and the signal electrode wirings 4 are divided into >=2 pieces to form the matrix of >=(2X2) intersected points. The generation of a disconnection as the TFT substrate is prevented in spite of the generation of the disconnection at one point by forming the intersected points as the matrix of >=(2X2). Since a shorting defect is correctable even if such defect arises and, therefore, wiring defects are eliminated. There is, therefore, an effect of improving the yield of the TFTs.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film transistor substrate used in a liquid crystal display device, and more particularly to a thin film transistor substrate having a high manufacturing yield.

[0002]

2. Description of the Related Art A conventional thin film transistor substrate includes a scan electrode wiring 2 connected to a gate electrode 1 of a thin film transistor 2, a signal electrode wiring 4 connected to a drain electrode 4 as shown in FIG. At least the semiconductor layer 6, the source electrode 7, and the display electrode 8 are formed. Therefore, there is one intersection 5 between the scanning electrode wiring 2 and the signal electrode wiring 4. This portion is usually electrically isolated by using an insulating film.

Further, in another conventional thin film transistor substrate, as shown in FIG. 4, the scanning electrode wiring 2 is a signal electrode wiring 4
There are two intersections 5a and 5b between the scanning electrode wiring 2 and the signal electrode wiring 4 in the vicinity (for example, Technical Report of the Institute of Electronics and Communication Engineers, ED-84, No. 159, p17 to p1).
9). In this example, the signal electrode wiring 4 also serves as the drain electrode 3, and the drain electrode 3 corresponds to the overlapping portion of the signal electrode wiring 4 and the gate electrode 1.

[0004]

In this conventional thin film transistor substrate, when there is a short circuit defect in the gate electrode 1 and the drain electrode 3, in the thin film transistor substrate of FIG. 3, the connection portion between the gate electrode 1 and the scan electrode wiring 2 is formed. It is possible to prevent a line defect by cutting with a laser or the like, and to prevent a line defect by cutting the scan electrode wiring 2 on the side of the gate electrode 1 which is divided into two scan electrode wirings 2 in FIG. Can be prevented. However, both of them have a problem that the short-circuit defect and the disconnection defect cannot be corrected at the intersection of the scanning electrode wiring 2 and the signal electrode wiring 4.

[0005]

The present invention provides a thin film transistor substrate having at least row-shaped scan electrode wirings connected to gate electrodes of thin film transistors and column-shaped signal electrode wirings connected to drain electrodes of the thin film transistors. The intersections of the scanning electrode wirings and the column-shaped signal electrode wirings are characterized by dividing the scanning electrode wirings into two or more and dividing the signal electrode wirings into two or more and forming the intersections into a matrix of 2 × 2 or more. ..

[0006]

The present invention will be described below with reference to the drawings. 1 is a plan view showing a thin film transistor substrate of a first embodiment of the present invention. A conductor is deposited on the substrate, patterned by using a photolithography technique, and then unnecessary portions of the conductor are removed by etching to form the gate electrode 1 and the scan electrode wiring 2. Next, an insulating layer and a semiconductor layer are continuously formed by the plasma chemical vapor deposition (PCVD) method, and the semiconductor layer 6 is formed by patterning using a photolithography technique and then removing the unnecessary semiconductor layer by etching. Next, a conductor is formed into a film and patterned by using a photolithography technique, and then the unnecessary part of the conductor is removed by etching to form the drain electrode 3 and the signal electrode wiring 4. Further, a transparent conductor was formed into a film and patterned by using a photolithography technique, and then an unnecessary portion of the transparent conductor was removed by etching to form a display electrode 8 to form a thin film transistor substrate. Scan electrode wiring 2 and signal electrode wiring 4
And, the intersections of them are both divided into two, and the intersection 5a
˜5d is a 2 × 2 matrix.

14-inch diagonal display number 1024 × 1024
Comparing the yield only for wiring defects in the case of manufacturing a × 3 color liquid crystal display with the conventional one shown in FIG. 3, the straight yield of the conventional one is 70%,
The yield including repairs is 75%, whereas that of the present invention is 75% in straight yield, and the yield including repairs is 9%.
It was 5%. The reason why the straight yield in the present invention is also improved is that the rate of prevention of defect occurrence due to disconnection is higher than the increase of defect occurrence due to short circuit. In addition, the reason why there is something that cannot be corrected is that if the short circuit has a high resistance, there is a defect that cannot be discovered unless assembled in the display, and when assembled in the display, it may not be possible to determine where the intersection points 5a to 5d are defective.

FIG. 2 is a plan view showing a thin film transistor substrate of a second embodiment of the present invention. The manufacturing method is the same as that of the first embodiment, but the display electrode is divided into 8a to 8d. The yield of this product was 75% for straight and the yield including repair was 100%. In the first embodiment, the defect could not be discriminated after it was assembled into the display, whereas in the second embodiment, the display electrode was displayed because the voltage applied to the display electrode near the defect location was different from the others. This is because, in this case, the display density is different from the others, and it is possible to determine the location of the intersection having a visual defect.

[0009]

As described above, according to the present invention, the scanning electrode wiring is divided into two or more and the signal electrode wiring is divided into two at the intersection point.
By dividing the matrix into two or more and dividing the matrix into 2 × 2 or more, even if a disconnection defect occurs, it can be repaired, so that the yield of the thin film transistor substrate can be improved.

[Brief description of drawings]

FIG. 1 is a plan view of a thin film transistor substrate according to a first embodiment of the present invention.

FIG. 2 is a plan view of a thin film transistor substrate according to a second embodiment of the present invention.

FIG. 3 is a plan view of a conventional thin film transistor substrate.

FIG. 4 is a plan view of another example of a conventional thin film transistor substrate.

[Explanation of Codes] 1 gate electrode 2 scan electrode wiring 3 drain electrode 4 signal electrode wiring 5, 5a to 5d intersection 6 semiconductor layer 7 source electrode 8, 8a to 8d display electrode

Claims (1)

[Claims] 1. In a thin film transistor substrate having at least a scanning electrode wiring connected to a gate electrode of a thin film transistor and a signal electrode wiring connected to a drain electrode of the thin film transistor, an intersection portion of the scanning electrode wiring and the signal electrode wiring is aforesaid. The scanning electrode wiring is divided into two or more and the signal electrode wiring is divided into two or more, and the intersection is 2 ×.
A thin film transistor substrate having a matrix of two or more.