JPH01183628A - Active matrix array - Google Patents

Abstract

PURPOSE:To prevent a constituent from being diffused into a liquid crystal by forming an insulator film in the vicinity of an intersection of a gate signal line and a source signal line, and also, on at least one of said signal line and a terminal of a thin film switching element. CONSTITUTION:As for this matrix array, a covered insulator film 17 is formed on a gate terminal and a drain terminal of a TFT. Also, this active matrix array is constituted as a liquid crystal display device, and when a defect of the TFT is generated after having injected a liquid crystal, one or both of the gate or drain terminals of the lower layer of the covered insulator film 17 is cut by using a laser. In such a case, the constituent of a cutting part 15a is diffused into the covered insulator film or the interface of a wiring and the covered insulator film as shown by a locus 16 of a scattered object. According to an experiment, said film is broken even when film thickness of the covered insulator film is about 1,000Angstrom , but it is scarcely diffused into a liquid crystal, and can be cut satisfactorily.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an active matrix array which is important as a component of a liquid crystal display device.

2. Description of the Related Art In recent years, with the miniaturization of industrial equipment, there has been a demand for thin flat display devices that can replace CRTs, which are conventional display devices.

Among various types of flat display devices, display values using liquid crystals are attracting attention as display devices for mobile devices 23 because they consume less power and can be driven by batteries. Driving systems for liquid crystal display devices for displaying images and characters can be roughly divided into simple matrix systems and active matrix systems, but the active matrix system is more advantageous in terms of contrast. However, in active matrix type liquid crystal display devices, it is necessary to form tens of thousands of switching elements or more over the entire active matrix substrate, and the technical issue is how to reduce defects in the switching elements. Although it is possible to reduce the number of defects by improving the manufacturing process of the active matrix substrate, it is difficult to eliminate them. Therefore, the development of defect correction technology is necessary for mass production of active matrix type liquid crystal display devices. A common method for repairing defects is to trim the defective area using a laser or the like and then separate the defective area.

An example of the conventional active matrix array mentioned above will be described with reference to the drawings. FIG. 7 is a partially enlarged view of switching elements and wiring sections of an active matrix type liquid crystal display device. However, some components unnecessary for the explanation are omitted. In FIG. 7, l is a pixel transparent electrode, 2 is a gate line, 3 is a source line, 4 is an insulating film, and 5 is a drain terminal. Further, a thin film transistor (hereinafter referred to as TPT) is formed in the portion within the hot spot line.

FIG. 8 is a sectional view taken along the AA' cross section of FIG. 7, with a glass substrate on which a transparent electrode is deposited and a color filter attached to the upper surface of FIG. 7, and a liquid crystal injected therebetween.

Further, FIG. 8 shows one terminal of the TPT being cut with a laser beam. In FIG. 8, 6 is an alignment film on the element surface, 7 is a liquid crystal, 8 is an alignment film on a filter surface, 9 is a color filter, 10 is a transparent electrode on the filter surface, 11 is a glass substrate on the element surface, 12 is a glass substrate on the filter surface, and 13 is a glass substrate on the filter surface. A laser light source, 14 is a laser beam, 15 is a cutting section, and 16 is a locus of a component scattered by the laser (hereinafter referred to as a trajectory of the scattered object).

Problems to be Solved by the Invention However, when trimming and repairing a conventional active matrix array with liquid crystal 7 injected in it, the components evaporated by the laser beam are quickly cooled by the liquid crystal shown in the figure. It ends up. Therefore, the component does not fly off and remains in the vicinity of the cut, making it difficult to cut it completely.

Although the above problem can be avoided by increasing the output of the laser, the thermal effect is then exerted on the area around the cutting point, causing deterioration of the surrounding components.

In addition, metal wiring etc. are peeled off from the element surface glass substrate 11,
One end of the electrode comes into contact with the filter surface transparent electrode IO, and electrical continuity occurs, causing the liquid crystal display device to become defective and irreparable.

Furthermore, the metal particles diffused into the liquid crystal 7 are moved by an electric field or the like when the liquid crystal display device is operated.

Therefore, there is a problem in that it adheres again to thin film switching elements and the like, causing defects and deteriorating the reliability of the device.

In view of the above-mentioned problems, the present invention has been devised to provide an active metal wiring that can be repaired well using laser output without peeling off the metal wiring from the glass substrate, and without affecting the surrounding area of the cut point, and without deteriorating reliability. A matrix array is provided.

Means for Solving the Problems In order to solve the above problems, an active matrix array of the present invention includes an insulator near the intersection of a gate signal line and a source signal line and on at least one of the signal and the terminal of the thin film switching element. It is formed by forming a film.

Function: According to the present invention, an insulating film is formed on the signal line or on the thin film switching element. Therefore, when the components are evaporated or scattered by irradiation with a laser beam as shown in FIG. 8, most of the scattered components fly away into the insulator film or at the interface between the wiring and the insulator film. Touching the liquid crystal directly becomes extremely rare. Therefore, trimming can be performed well with the laser output without separating the metal wiring from the glass substrate, without affecting the area around the cutting point, and without causing the components to diffuse into the liquid crystal. do not have.

EXAMPLE Hereinafter, an active matrix array according to an example of the present invention will be described with reference to the drawings.

FIG. 1 shows a plan view of an active matrix array in a first embodiment of the present invention. In FIG. 1, 17 is an insulator film (hereinafter referred to as a covering insulator film). The thickness of the covering insulator film is 15! Although it varies depending on the quality, for Siμχ, a minimum thickness of 1000 Å or more is required, preferably 3000 Å or more, and more preferably 6000 people.

The same applies to the S + 02 film, and the same thickness is desirable when the covering insulator film is made of an organic material such as polyimide.

FIG. 2 is a sectional view taken along line BB' in FIG. 1. As is clear from FIGS. 1 and 2, in the first embodiment of the present invention, a covering insulator film 17 is formed on the gate terminal and drain terminal of the TPT. After configuring the active matrix array as a liquid crystal display and injecting liquid crystal, TP
If a T defect occurs, one or both of the gate and drain terminals in the lower layer of the covering insulator film 17 are cut using a laser.

FIG. 3 shows one terminal of the TPT of an active matrix array injected with the liquid crystal of the present invention being cut with a laser beam. The constituents of the cut portion 15 diffuse into the covered insulator 11116 or at the interface between the wiring and the RFI insulator 16, as shown by the trajectory 16 of the scattered particles. Therefore, it is not directly cooled by the liquid crystal 7.
When the thickness of the cutting portion 15 was 2,000 Af and the thickness of the covering insulator was 4,000, good cutting results were obtained with a laser power of 0.8 μJ. Experiments have shown that even if the coating insulator film has a thickness of about 1,000 layers, the film is torn, but it can be cut well without being diffused into the liquid crystal.

FIG. 4 shows a plan view of the active matrix array in the embodiment of FIG. 2 of the present invention. In FIG. 4, reference numeral 18 denotes a covering insulator 1 pattern 18 formed near the gate signal line 2 and the source signal line 3 and on the source signal line 3.
It is. FIG. 5 is a sectional view taken along line CC' in FIG. 4. As is clear from FIGS. 4 and 5, a covering insulator 11918 is formed near the intersection of the signal lines. When a short circuit defect occurs at the intersection of the signal lines, the covering insulator film 18
By trimming the lower layer signal lines, it is possible to correct a defect commonly called cross-over.

FIG. 6 shows a plan view of an active matrix array in a third embodiment of the present invention. In FIG. 6, reference numeral 19 denotes a covering insulator film that simultaneously covers the vicinity of the intersection of the gate signal line 2 and the source signal line 3 and all the terminals of the TPT. As is clear from FIG. 6, when the intersection of the signal lines and the terminal of the thin film switching element are located close to each other, it is sufficient to form the ffi insulator film 19 covering both at once.

Effects of the Invention As described above, in the active matrix array of the present invention, by forming the covering insulating film, the constituents at the trimming position can be diffused into the covering insulating film or at the interface. Therefore, the constituents will not diffuse into the liquid crystal, and the display quality or reliability of the liquid crystal display device will not be degraded by the constituents. Furthermore, since the component at the trimming position is not directly cooled by the liquid crystal, trimming can be performed with a much lower laser output than in the past. Therefore, there is no problem that thermal effects are exerted on the components around the trimming, causing them to change in quality, and that metal wiring or the like peels off from the glass surface. In view of the above, the effects of the present invention are significant.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an active matrix array according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line BB' in FIG. FIG. 4 is a plan view of an active matrix array according to a second embodiment of the present invention, and FIG.
The figure is a sectional view taken along line cc' in Figure 4, and Figure 6 is a cross-sectional view taken along the line cc' in Figure 4.
FIG. 7 is a plan view of a conventional active matrix array, and FIG. 8 is an explanatory diagram of a conventional active matrix array modification method. 1... Picture element transparent electrode, 2... Gate signal line, 3... Source signal line, 4... Insulating film, 5...・Drain terminal, 6...Element surface alignment film, 7...Liquid crystal, 8...Filter surface alignment film, 9...Color filter, 10.
... Filter surface transparent electrode, 11 ... Element surface glass substrate, 12 ... Filter surface glass substrate, 13 ... Laser light source, 14 ... - Laser light, 15...cutting section, 16...trajectory of scattered objects, 17.18.19...coating insulator film. Name of agent: Patent attorney Toshio Nakao Haka 1 person/--Ichisu Soho Meiden 1 2-Ge'-To 屹Goren 3- Source Ig Gogo 4-Eleven Shoju 5-Drain A child No. Fig. 2 Fig. 3 Fig. 5 Fig. 6 Fig. 1 (/-Jakubaku) Color record bar

Claims (2)

[Claims] (1) An active matrix array used in a transmissive liquid crystal display device, in which an insulating film is formed near the intersection of a gate signal line and a source signal line and on at least one of the signal line and the terminal of a thin film switching element. An active matrix array characterized by: (2) The active matrix array according to claim (1), wherein the insulating film has a thickness of 1000 Å or more.