JP2000155307A - Liquid crystal display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a defective ratio of a liquid crystal display panel and to improve productivity. SOLUTION: Capacity in an intersecting part can be reduced and static electricity is made hard to be generated by forming a new insulation film layer 15 at a part at which a common bus wiring 1 and a connection wiring 10 intersect, and a picture test is surely performed and yield is improved. In this case, the panel is constituted so that either or both of area of a part at which the common bus wiring 1 and the connection wiring 10 intersect are made small, and when the new insulation film layer 15 is formed, further, static electricity is made hard to discharge.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display panel.

2. Description of the Related Art As shown in FIG.
It is made of soft, low-resistance metal Al with a sheet resistance of about 0.2Ω / □, or an Al-based alloy containing Al with a high melting point metal such as Ta (tantalum) or Ti (titanium) of about 3%. A plurality of scanning signal lines 3 and a plurality of video signal lines 2
And a transparent conductive film (IT
O). An image is displayed by controlling a voltage applied to each liquid crystal cell of the pixel electrode 6 by a TFT transistor. In the manufacturing process of such a liquid crystal display panel, failures occur due to various causes such as abnormal patterning due to dust and destruction of the element due to static electricity etc.Therefore, the inspection probe electrode is brought into contact with all the electrodes mounted on the liquid crystal driving LSI. Inspections are performed a plurality of times in the manufacturing process, and manufacturing is performed. However, in recent years, high definition has been promoted to improve display quality, and the number of pixels tends to increase. Therefore, LSI for driving liquid crystal
The spacing between the mounting electrodes becomes narrower, the contact spacing between the inspection probe electrodes for performing the inspection multiple times in the manufacturing process described above also becomes narrower, and the probe electrodes are arranged one by one for video signal wiring and scanning signal wiring. The contact makes the production cost extremely expensive and prolongs the production period. In addition, the stability of the contact of the probe electrode and the maintenance of the probe electrode are very difficult. In particular, a liquid crystal display panel using a chip-on-glass method in which a liquid crystal driving LSI driver is directly mounted on a glass substrate cannot directly contact an electrode pad. Therefore, it is desired that the development cost of a probe or the like be reduced, the development period be shortened, and a simple signal and a simple probe be used for inspection. Therefore, as a simple inspection method, as shown in FIG. 3, the inspection electrode terminals 9 are formed on the common bus wiring 1 connected to at least one of the plurality of video signal wirings 2 and the plurality of scanning signal wirings 3 of the liquid crystal display panel. An inspection probe is set up at this terminal, and an inspection signal 13 is supplied to inspect the liquid crystal display panel to judge pass / fail. Thereafter, at least one of the video signal wiring 2 and the scanning signal wiring 3 connected to the common bus wiring 1 provided in the unmounted portion outside the liquid crystal screen 8 is cut with a laser beam as shown in FIG. The final form of the liquid crystal display panel is obtained by cutting the portion 11 to be formed. In particular, in recent years, competition for cost reduction of liquid crystal panels has intensified, and such a chip-on-glass method has been applied not only to AV but also to OA fields. FIG. 4 shows an enlarged view and a sectional view of a portion where the common bus wiring and the connection wiring intersect. In the related art, the connection wiring and the common bus wiring intersect as they are, and only the insulating film layer is provided at the step.

However, in recent years,
The cost reduction, high definition, and narrow frame of liquid crystal panels have accelerated, and the chip-on-glass method has come to be used for large-sized panels. However, if the conventional method is used, the cross capacitance between the connection wiring, the video signal wiring, and the scanning signal wiring increases with an increase in screen size, and static electricity easily occurs. Therefore, if static electricity occurs at a portion where the video signal wiring and the scanning signal wiring intersect with the connection wiring, an image electrical inspection cannot be performed accurately in a panel state, and it becomes difficult to detect a panel failure. SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and provides a liquid crystal display panel capable of reliably performing an electrical test in a panel state and preventing a defect from being introduced in a subsequent process.

According to a first aspect of the present invention, there is provided a liquid crystal display panel, wherein a common bus line is formed so that an image electrical inspection of the liquid crystal display panel can be performed, and a plurality of scanning signal lines and a plurality of images are provided on the common bus line. Connect the signal wiring with connection wiring,
A new insulating film layer is provided on the insulating film layer at the intersection of the connection wiring and the common bus wiring. A liquid crystal display panel according to a second aspect is characterized in that, in the first aspect, the area of one or both of the intersections of the scanning signal wiring and the video signal wiring with the connection wiring is reduced. According to a third aspect of the present invention, in the liquid crystal display panel according to the first or second aspect, the connection wiring is formed of a transparent conductive film (ITO). According to a fourth aspect of the present invention, in the liquid crystal display panel according to the first to third aspects, the connection wiring has a sheet resistance of 10Ω / □.
It is characterized by being formed as described above.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A liquid crystal display panel according to a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic diagram showing the configuration of a liquid crystal display panel according to an embodiment of the present invention. The same components as those of the liquid crystal display panel shown in FIG. 3 are denoted by the same reference numerals, and detailed description will be omitted. This liquid crystal display panel is similar to the liquid crystal display panel shown in FIG.
At least one of the plurality of video signal lines 2 and the plurality of scanning signal lines 3 is connected to a common bus line 1 provided outside the liquid crystal screen by a connection line 10. As shown in FIG. 1, a new insulating film layer 15 is newly formed at a portion where the common bus wiring 1 and the connection wiring 10 intersect. FIG. 1-1 shows a cross-sectional view taken along the line aa ′. Conventionally, only the insulating film layer 14 is provided between the common bus wiring 1 and the connection wiring 10 as shown in FIG. However, in the present invention, this insulating film layer 1
4, a new insulating film layer 15 is newly formed. Therefore, by newly forming this new insulating film layer 15, the film thickness at the portion where the connection wiring 10 and the common bus wiring 1 intersect can be increased, and the capacitance value decreases as compared with the conventional case. Is less likely to occur. At this time, the newly formed new insulating film layer 15 was formed at about 1500 °. or,
The new insulating film layer 15 can be easily formed by a TFT forming process without adding a new process. For example, an insulating film layer is formed by the same process using a mask at the time of forming the SiNx layer in the channel portion of the Tr portion. Therefore, with the above configuration, the common bus wiring 1 and the connection wiring 1
The static electricity does not fly between 0 and the image electrical inspection can be performed reliably, which leads to an improvement in yield. FIG. 2 shows the second
1 shows a liquid crystal display panel of an embodiment. In this case, one or both of the crossing areas of the common bus wiring 1 and the connection wiring 10 are configured to be small. Also at this time, the area of the intersecting portion can be reduced, and the static electricity can be prevented from flying. For example, the capacity ratio can be reduced by about 25% at an area ratio of about 25% ± 5%. This area ratio is the same as the effect of quadrupling the thickness of the insulating film. Also, as shown in FIG.
If the area is made smaller and the new insulating film layer 15 is formed, the static electricity is less likely to fly. Other configuration effects are
This is the same as the embodiment. If a transparent conductive film (ITO), which is a material having a high hardness, a high resistance and a high melting point, is used as one of the materials of the connection wiring, it can be easily formed in the process because the same material as the pixel electrode is used. This leads to cost reduction and productivity improvement. In each of the above embodiments, the active driving method using a thin film transistor or the like that forms video signal wiring and scanning signal wiring on the same glass substrate is used, but the simple matrix driving method that forms these wirings separately is used. Can be applied in the same manner. In each of the above-described embodiments, the present invention is similarly applied to both the video signal wiring 2 and the scanning signal wiring 3. However, even when the present invention is applied to one of the wirings, compared with the conventional method. And good results are obtained.

According to the liquid crystal display panel of the first aspect, the film thickness can be increased by forming a new insulating film layer at a portion intersecting the common bus wiring and the connection wiring. Therefore, it is possible to make it difficult for the static electricity to fly at the intersections, and to perform the image inspection accurately. It leads to improvement of productivity and yield. According to the liquid crystal display panel of the second aspect, by reducing the area of one or both of the intersections of the common bus wiring and the connection wiring, the capacitance of that part can be reduced. Also in this case, the same effect as the first aspect can be obtained.
In addition, when the configuration of the first and second aspects is combined, the capacitance between the common bus wiring and the connection wiring can be further reduced, and static electricity hardly occurs. In the liquid crystal display panel according to the third aspect, the use of the transparent conductive film (ITO) which can form the connection wiring most easily in the process in the first or second aspect leads to cost reduction.
According to a fourth aspect of the present invention, there is provided the liquid crystal display panel according to the first or second aspect, wherein the connection wiring has a sheet resistance of 10 or less.
Ω / □ or more to prevent dielectric breakdown due to static electricity,
The determination of the line defect in the inspection becomes reliable.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a liquid crystal display panel according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a liquid crystal display panel according to a second embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a conventional liquid crystal display panel.

FIG. 4 is a schematic configuration diagram of a conventional liquid crystal display panel.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Common bus wiring 2 Video signal wiring 3 Scanning signal wiring 4 Gate driver 5 Source driver 6 Pixel electrode 7 Glass substrate 8 Liquid crystal screen 9 Inspection electrode terminal 10 Connection wiring 11 Portion cut by laser beam 12 Connection part 13 Inspection signal 14 Insulation Film layer 15 New insulating film layer

Continued on the front page (72) Inventor Shinichi Hoshino 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F term (reference) 2H088 EA02 FA12 HA02 HA04 2H090 HA02 HA05 HD01 JC18 LA01 2H092 GA33 GA35 JA24 JB23 JB24 JB32 JB33 JB33 JB73 JB77 JB79 KB05 KB25 MA30 MA47 NA14 NA30 5G435 AA00 AA17 BB12 EE34 EE41 HH12 HH15 KK05

Claims (4)

[Claims] 1. A common bus line is formed so as to perform an image electric inspection of a liquid crystal display panel, a plurality of scanning signal lines and a plurality of video signal lines are connected to the common bus line by connection lines, and the image electric inspection is completed. After that, in the configuration of the liquid crystal display panel in which the connection wiring is cut by laser light, a new insulating film layer is placed on the insulating film layer at the intersection of the connection wiring and the common bus wiring. . 2. The liquid crystal display panel according to claim 1, wherein an area of one or both of the intersections of the common bus wiring and the connection wiring is reduced. 3. The liquid crystal display panel according to claim 1, wherein the connection wiring is formed of a transparent conductive film (ITO). 4. A connection wiring having a sheet resistance of 10Ω /
□ or claim 3 or claim 3 formed to be more than
The liquid crystal display panel according to 1.