JPH0239029A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To facilitate electric disconnection due to laser of a liquid crystal display device securely in a stage of generation of short-circuit at a crossed part of a signal wiring with a scanning wiring by constructing a part of wirings with a metal oxide. CONSTITUTION:Wirings 14, 14' in a part of scanning lines 7 are constructed with a metal oxide, for example, consisting of In Sn, and O. The scanning line 7 is formed with some distance (d) by using an electroconductive metal, and wiring 14, 14' comprising the metal oxide are formed on its upper layer so as to connect the distance (d) between the scanning line (electroconductive metal) 7 electrically. When in this case, an insulating layer 16 is interposed between the scanning line 7, the wiring 14, 14' using the metal oxide are formed after providing an opening 10 to the insulating layer 16. Thus, when short-circuit is generated in a crossed part of the scanning line 7 with a signal line 8, it is necessary, for example, to cut the wiring parts 14, 14' of the scanning line 7 with laser.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to the structure and material of the wiring portion of a liquid crystal display device.

BACKGROUND OF THE INVENTION In recent years, with advances in microfabrication technology and liquid crystal materials, television image display devices using liquid crystal panels have come to be provided on a commercial basis. Furthermore, as a method, the so-called active method, in which a switching element is built into each picture element, is becoming mainstream due to its advantages such as high contrast and high resolution.

FIG. 3 shows a circuit of an active type liquid crystal panel, in which a switch element 3, such as a field effect transistor, and a liquid crystal cell 4 are arranged at each intersection of a scanning line 1 and a signal line 2. Reference numeral 5 denotes a counter electrode made of a transparent conductive layer common to all liquid crystal cells 4.

FIG. 4 is a plan view of a general active type unit picture element, and FIG. 5 is a sectional view taken along the line A-A' in the figure. A conductive layer 7 serving as a scanning line and a gate of a field effect transistor is formed on an insulating substrate 11, for example, a glass substrate 11, and an amorphous silicon layer 13, a signal line 8, and a drain 9 line are connected via an insulating layer 12. 9 to form a field effect transistor. Here, 6 indicates a picture element electrode, and 10 indicates an opening.

Problems to be Solved by the Invention However, the above configuration has a problem of low yield due to the complicated structure.

The main cause of this low yield is poor insulation of the insulating layer 12, such as a short circuit between the gate and the source. This defect becomes a cross line defect on the image, significantly lowering the display quality, and posing a serious problem in practice. Therefore, in actual production, when considering improvement in yield, defects in the insulating layer 12 become a problem that cannot be ignored. Therefore, in order to eliminate the line defect caused by this short circuit defect, it becomes necessary to repair the line defect defect.Currently, the method for repairing this defect is carried out at the time of forming the thin film transistor array, or by liquid crystal injection at the time of attaching the counter substrate. After that, the mainstream method is to use a laser to cut the defective wiring.However, the low resistance metals used for these wirings, such as AI and C
Since r has high extensibility and reflectance, it is suitable for high-power lasers,
For example, when cutting using a YAG laser, the cut surface extends in a complicated manner, making it difficult to ensure electrical disconnection of the wiring. If the output is increased too much, bubbles are generated in the liquid crystal due to the heat during irradiation, which causes display unevenness in images.

In view of the above problems, the present invention provides a liquid crystal display device including a wiring portion that is easily cut when irradiated with a laser.

Means for Solving the Problems In view of the above, the present invention is a liquid crystal display device having a structure in which metal oxide is used for part of the wiring in order to facilitate and ensure electrical disconnection by laser.

Function The present invention provides that a part of the wiring forming the picture element transistor is
By using conductive materials or metal oxides with low extensibility, that is, hard and brittle, and low reflectance, the laser irradiation area can be easily cut, ensuring reliable electrical wiring. It makes it possible to open up.

Embodiment FIG. 1 is a plan layout diagram of the picture elements of a liquid crystal display device according to an embodiment of the present invention. How to show.

First, as shown in FIG. 1, part of the scanning line 7 is formed in the form of wiring 14, 14 using metal oxide. As the metal oxide, for example, a material consisting of indium, tin, and oxygen can be used. As shown in FIG. 2 (al), the method of forming this is to form the scanning lines 7 with a certain interval d using a conductive metal, and to form the wiring 414 made of metal oxide in the upper layer.
．． 14' is formed to electrically connect the scanning lines (conductive gold@) 7 at intervals d. At this time, if the insulating layer 16 is interposed above the scanning line 7, the insulating layer 16 has an opening at
After providing the wirings 14 and 14' made of metal oxide are formed. Alternatively, as shown in FIG. 2 fbl, a method may be used in which metal oxide interconnects 14, 14' are first formed, and scanning lines 7 are formed thereon at a certain interval d. If an insulating layer 16 is interposed between the scanning line 7 and the metal oxide wiring 14, 14', connection can be made by providing an opening 10 in the insulating layer 16 as in the example of FIG. 2a. ,
As shown in FIG. 1, a portion of the signal line 8 may be made of metal oxide to form interconnections 15 and 15'. The formation method may be the same as that for the scanning lines.

As described above, in the liquid crystal display device formed according to this embodiment, if a short circuit occurs at the intersection of the scanning line 7 and the signal line 8, for example, the wiring 1 made of a metal oxide of the scanning line 7
4. The 14' portion may be cut using a laser.

As described in detail, according to the present invention, a part of the wiring is formed using a metal oxide, so that when a short circuit occurs at the intersection of the signal wiring and the scanning wiring, the electrical It can be opened easily and reliably,
The repair of the short-circuit defect is dramatically improved, and the practical effects thereof are significant.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the main parts of a liquid crystal display device according to an embodiment of the present invention, FIG. 2 1 and b are sectional views of main parts of different examples of the same device, and FIG. 3 is an active liquid crystal display. An equivalent circuit diagram of the device, FIG. 4 is a plan layout of unit picture elements of a conventional semiconductor device for a liquid crystal display device, and FIG. 5 is a sectional view of a main part of the device. 6... Picture element electrode, 7... Scanning line, 8...
...Signal line, 9...Drain wiring, 10
...Opening, 13...Amorphous silicon, 14.14ζ 15.15'...Metal oxide. Name of agent: Patent attorney Shigetaka Awano and 1 other person 1st
Figure 7--Quantitative line 8--Signal section 74, t4', /S, ts'-4: ξIzumi δ-・Signal p/4. t+: ts, ts'-+ -Pair of usu kameya E? 6゛-Silicon electric supply γ・-scanning"Izumi B-・Kagami q-Y rain wiring ΔIzumi II-One-wire board/Z-One-wire wire

Claims (2)

[Claims] (1) A liquid crystal is sealed between a pair of substrates, a pixel electrode arranged in a matrix on one of the substrates, a switching transistor connected in close proximity to the pixel electrode, and a switching transistor connected to the pixel electrode. In a liquid crystal display device comprising a signal wiring connected to a source electrode and a scanning wiring connected to a gate electrode of the switching transistor, at least one of the signal wiring and the scanning wiring in the pixel unit A liquid crystal display device characterized in that a metal oxide is used for a portion thereof. (2) The liquid crystal display device according to claim 1, wherein the metal oxide contains indium or tin.