JP2003005205A - Liquid crystal display device, manufacturing method thereof and image display application device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To detect spots and the like and to prevent static electricity, a plurality of source and gate signal lines are connected after inspection or before completion of a liquid crystal panel. Signal lines are disconnected. In this case, after the separation step, static electricity from workers, corrosion by moisture,
The problem of foreign matter due to cutting chips occurs, and the yield decreases. SOLUTION: A pattern of a sealant 3 for sealing a liquid crystal,
In addition to the liquid crystal sealing pattern around the display area, a pattern 3b surrounding the periphery of the portion where the wiring is cut is provided. Then, laser cutting is performed in the sub-sealing portion surrounded by the pattern 3b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, a manufacturing method thereof and an image display application device.

[0002]

2. Description of the Related Art Conventionally, a liquid crystal display device has a plurality of pixel electrodes arranged in a matrix and a counter electrode which is a common electrode arranged so as to face these pixel electrodes. A certain liquid crystal is interposed. In displaying, a potential is selectively written in the pixel electrode, and the potential difference between the pixel electrode and the counter electrode optically modulates the intervening liquid crystal, and is visually recognized as a display pattern.

By the way, as a method of inspecting such a liquid crystal display device, usually, an optical inspection in each step of the process, an electrical inspection at the stage when the active matrix substrate is completed, and before mounting a mounting member such as a driver. The lighting inspection and electrical inspection are performed when the panel portion of is completed.

This is to prevent waste of material and work by flowing the defective portion to the subsequent process. If there is a defect, it is discarded at this point or corrected by a means such as a laser. Is applied.

In the electrical inspection at the stage where the conventional active matrix substrate is completed, it is not presently defective in order to suppress the occurrence of defects in the market, but defects such as short circuit due to the change with time after completion as a product. A short ring was used to perform a screening step in which a crossing portion of a gate wiring and a source wiring, which may become a defect, is made defective in the process.

Specifically, all the gate wirings are connected to the gate wiring short ring and all the source wirings are connected to the source wiring short ring, and a high voltage is applied between the two short rings, resulting in a failure. Potential TF
T and the auxiliary capacity were destroyed.

Further, the location of the defective portion after the active matrix substrate is completed and the electrical inspection is completed is determined by the lighting inspection and the electrical inspection after the panel portion before mounting the mounting member such as the driver is completed. If there is a problem, it is discarded at this point, or it is corrected by means such as a laser.

In these electrical inspections and lighting inspections, a wide range of liquid crystal panels having different sizes and numbers of pixels are used, and the influence of static electricity generated in the liquid crystal panel manufacturing process on the semiconductor layer is reduced. In order to ensure that there is one inspection terminal for each signal line of the gate and source
It is composed of a few or several lines, and a plurality of signal lines are connected to one inspection terminal. In this configuration, each wiring is short-circuited, and as a method of short-circuiting each wiring, there are a method of short-circuiting in one layer and a method of utilizing two or more layers. In the electrical inspection and lighting inspection, a short circuit using two or more layers is used because of the inspection method. Therefore, after the inspection, a step of disconnecting the plurality of short-circuited signal lines is required. This cutting step is performed by a cutting means such as a laser after the lighting inspection. The cut portion is a portion which does not come into contact with the outside air, such as under the driver IC, and is configured to suppress the generation of static electricity and corrosion.

However, when each wiring is short-circuited as a countermeasure against static electricity, it is more effective to prevent static electricity by short-circuiting only one layer. Description will be made with reference to the gate wiring of FIG. 4 and the cross-sectional view of FIG. FIG. 4A is a schematic plan view of a liquid crystal display device in which a cutting portion is arranged under a conventional sealant, and FIG. 4B is a partially enlarged view thereof. This liquid crystal display device includes an array substrate 1 of an active matrix type liquid crystal display panel, a counter substrate 2 facing the array substrate with a gap, and a liquid crystal sealing formed around the array substrate 1 and the counter substrate 2. And the sealing agent 3. The array substrate 1 is provided with a plurality of gate wirings 4 and a plurality of source wirings 5 intersecting each other,
A display region 6 in which pixel electrodes and pixel switching elements are arranged in a matrix along the source wiring 5 is provided. Then, on the terminal side of the gate wiring, all gate wirings have a cutting region 7 which is cut by a laser. All the gate wirings are connected as one wiring at the connection portion 8 at a position closer to the outer shape than the cutting area 7, and the cutting area 7 is arranged under the sealant 3 for liquid crystal sealing.

Specifically, when the gate wirings 4 are independent of each other, the charge amount of each gate wiring 4 is different for each gate wiring, and the characteristics of the semiconductor layer connected to each gate wiring are different due to the charging. Therefore, when the panel is turned on after the completion of the panel, the characteristic change of the semiconductor layer for each gate wiring is recognized as an image quality defect such as stripes or unevenness. In two or more layers, the effect of static electricity measures does not appear until a pattern that actually short-circuits is formed. In order to make static electricity countermeasures more effective, the gate and source signal lines should all be short-circuited in a single layer inside or outside the panel outline size, and the gate and source signal lines should be at the same potential. Most effective is expected to be kept. However, as in the case described above, a step of disconnecting the short-circuited wiring is required before the liquid crystal panel is completed. The cutting area 7
Are laid out under the sealant 3 for liquid crystal encapsulation, and are cut by means such as a laser when the array substrate is completed. This avoids contact with the outside air and suppresses the occurrence of static electricity defects and corrosion defects in the subsequent process.

The relationship between the array substrate, the sealant and the cut area will be described with reference to the sectional view of the liquid crystal panel of FIG. FIG. 5 is a cross-sectional view of the portion of the wiring cut in FIG. 4 from the front direction. The cut region 7 cut by means such as a laser after the completion of the array substrate is laid out under the sealant 3 by applying a sealant and sticking the sealant in a panel assembling process.

[0012]

A conventional inspection terminal is composed of one or several lines for each signal line of gate and source, and a plurality of signal lines are connected to one inspection terminal. In this configuration, each wiring is short-circuited with each other, and a step of disconnecting the plurality of connected signal lines is required after the inspection or before the completion of the liquid crystal panel. This step of separating is roughly divided into two, that is, the step of arraying the insulating transparent substrate and the step of laminating the liquid crystal panels. In the former case, the insulating transparent substrate is cut off by a means such as a laser when the array process is completed. In the latter case, the insulating transparent substrate is cut into a panel size by using a cutting process, or by a laser or other means after a lighting inspection after the panel part is completed.

When the insulating transparent substrate array process is completed at the stage where it is cut off by means of a laser or the like, the scraps of the cut parts cause foreign matter defects around the cut parts after the panel is completed. Further, in order to reduce foreign matter defects, it is necessary to introduce a cleaning step after cutting with a laser or the like, which increases the number of steps. Incidentally, the cut portion is covered with a sealant in order to avoid corrosion when the panel is completed.

In the case where the connected wirings are cut using the cutting step of cutting out from the insulating transparent substrate to the size of the panel, there is a wiring end on the cut surface. Therefore, in the subsequent manufacturing process, it becomes very difficult to prevent static electricity from being mixed in by the jig supporting portion or an operator at the time of inspection, and the yield is reduced. Further, even after the completion of the liquid crystal display device, there is a drawback that the electrolytic corrosion of the wiring occurs from the cut end surface due to the potential applied to the wiring and the moisture from the outside air during long-term use.

When the wirings connected by the laser are cut off after completion of the panel portion, and the cutting place is on the panel outer side than the sealant for sealing the liquid crystal, in the same manner as above, in the long-term use, There is a problem that electrolytic corrosion occurs from the cut end surface of the wiring due to the potential of the wiring and the moisture from the outside air.

When the cutting place is closer to the pixel display portion than the sealant for sealing the liquid crystal, bubbles are generated from the liquid crystal at the time of cutting, and impurities are mixed into the liquid crystal material due to generation of cutting chips. However, there is a problem that the quality of the liquid crystal display device is deteriorated.

When the place to be cut is covered with a sealant that seals the liquid crystal, the sealant absorbs the laser, so that the disconnection of the wiring is not stable, and the disconnection of the wiring frequently occurs. there were.

The present invention solves the above-mentioned conventional problems, without adding a cutting step and a washing step in the array step,
It is intended to suppress the occurrence of defects such as foreign matter and liquid crystal bubbles in the panel due to cutting, and also to suppress the occurrence of corrosion at the cut part in long-term reliability, and to reduce the occurrence of streaks and unevenness in display quality. .

[0019]

According to a first aspect of the present invention, a display pixel electrode is formed on an insulating transparent substrate through a thin film transistor and a gate wiring and a source wiring for driving the thin film transistor, and at least one of the wirings is formed. A liquid crystal display device comprising: an array substrate formed by short-circuiting parts outside the display region; a counter substrate facing the array substrate via a gap; and liquid crystal injected between the array substrate and the counter substrate. A sealant formed from an annular main seal part for liquid crystal sealing formed around the display regions of the array substrate and the counter substrate and an annular sub seal part formed on the outer side thereof, It is characterized in that the area surrounded by the seal portion is used as a cutting point of the wiring arranged on the array substrate.

According to a second aspect of the present invention, in the liquid crystal display device according to the first aspect, the wiring is either a gate wiring or a source wiring.

According to a third aspect of the present invention, a display pixel electrode is formed on an insulating transparent substrate through a thin film transistor and a gate wiring and a source wiring for driving the thin film transistor, and at least one of the gate wiring and the source wiring is displayed. A short circuit is made outside the area, a ring-shaped main seal portion is formed around the display area of the array substrate and the counter substrate, and a ring-shaped sub-seal portion is formed at the wiring short-circuit portion outside the display area. And liquid crystal is injected into a region surrounded by the main seal portion between the opposing substrates, and the short-circuited wiring pattern is cut in the region surrounded by the sub seal portion.

The image display application device according to claim 4 of the present application is characterized by including the liquid crystal display device according to claim 1 or 2.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION (Embodiment 1) Hereinafter, a liquid crystal display device according to Embodiment 1 of the present invention will be described with reference to the drawings, taking a case where a gate wiring is short-circuited as an example. First, as shown in FIG. 2, a pattern in which the gate wiring 4 is short-circuited is formed on the array substrate 1 in the initial stage of array production, and then other patterns such as the source wiring 5 are formed to complete the array substrate. Then, it is put into a panel assembling process, and the sealant 3 as shown in FIG. 1 is applied on the array substrate 1 by a seal printing machine or the like, and then the array substrate 1 and the counter substrate 2 are bonded in a bonding process.

FIG. 1A is a schematic plan view of a liquid crystal display device according to Embodiment 1 of the present invention, and FIG. 1B is a partially enlarged view thereof. In FIG. 1, a liquid crystal display device 1 is formed of an array substrate 1 of an active matrix type liquid crystal display panel, a counter substrate 2 facing the array substrate with a gap, and a periphery of the array substrate 1 and the counter substrate 2. And a sealant 3 for sealing liquid crystal. The array substrate 1 includes a plurality of gate wirings 4 and a plurality of source wirings 5 that intersect each other.
Is provided, and a display area 6 is provided in which pixel electrodes and pixel switching elements are arranged in a matrix along the gate wiring 4 and the source wiring 5. On the terminal side of the gate wiring, all the gate wirings have a cutting region 7 which is cut by a laser, and all the gate wirings are connected as one wiring at a connecting portion 8 closer to the outer shape than the cutting region. In addition to the liquid crystal sealing pattern 3-a in the display area, the sealant 3 for liquid crystal sealing has a pattern 3-b surrounding the portion of the gate wiring cut by the laser, in addition to the liquid crystal sealing pattern 3-a. . Hereinafter, the seal portion of the display area is referred to as a main seal portion, and the seal portion covering the cut portion is referred to as a sub seal portion.

After that, the individual panels are cut out in a cutting process using a cutter or the like. The cutting of the gate wiring 4 in the cutting region 7 by a laser or the like may be performed before or after the cutting step. When the cutting and cutting of the panel and the cutting of the short-circuit wiring by the laser are completed, the panel assembling process is completed and the process is passed to the next process such as inspection.

FIG. 3 is an enlarged sectional view of a portion cut by the laser shown in FIG. The operation of the liquid crystal display panel configured as described above will be described below with reference to the drawings. As in the pattern 3-b in FIG. 1, the portion to be laser cut is surrounded by a sealant for liquid crystal sealing to form a sub seal portion. When cutting the connected wirings, the cut surface is inside the sub seal portion inside the end of the panel. Therefore, in the subsequent manufacturing process, it is possible to suppress the mixing of static electricity from the supporting portion of the jig or the worker at the time of inspection. Further, even after the completion of the liquid crystal display device, since the mixing of water from the outside air does not occur during long-term use, the occurrence of electrolytic corrosion from the cut end face can be suppressed. Further, since the cutting region 7 is a region different from the display region 6, even if bubbles are generated from the liquid crystal at the time of cutting or cutting chips are generated, there is no problem such as mixing of impurities into the liquid crystal material. , Does not occur. Further, since the place to be cut is not covered with the sealant, it is possible to prevent defective cutting of the wiring due to the absorption of the laser beam by the sealant.

Further, by surrounding the portion to be cut by the laser with the sealant, the wiring cutting process can be delayed from the completion of the array substrate to the latter half of the panel assembling process. Therefore, after the panel laminating step, laser cutting can be easily performed without worrying about reduction in yield. Therefore, at the stage when the array process is completed, the connecting portion is cut off by means such as a laser,
Moreover, it is not necessary to introduce a cleaning process for removing the scraps of the cut portion.

As described above, according to the present embodiment of the present invention, by enclosing a necessary portion for laser cutting in the liquid crystal panel with a sealant for liquid crystal sealing, corrosion and foreign matter defects caused by laser cutting are prevented. It is possible to easily reduce the display quality, and it is possible to improve the display quality such as lines and unevenness when the screen is displayed. In the above embodiment, the case where the gate wiring is short-circuited has been described, but even when the source wiring is short-circuited outside the display area, the same effect can be obtained by surrounding the cut portion with the auxiliary seal portion. Can be obtained.

The above liquid crystal display device can be mounted on various image display application equipment. Image display application devices include personal computers (notebook personal computers), mobile terminals (PDAs), mobile phones, portable television receivers, and the like.

[0030]

As described above, according to the present invention, a region surrounded by the sealant is formed outside the pattern formed by the sealant for sealing liquid crystal, and the wiring arranged on the array substrate in the region is formed. Is designed to be cut. This eliminates the need for additional cutting and cleaning steps in the array process, suppresses the occurrence of defects such as foreign matter in the panel and liquid crystal bubbles due to cutting, and also prevents corrosion of the cut part in long-term reliability. In addition to suppressing, the effect of reducing streaks and unevenness in display quality is also obtained.

[Brief description of drawings]

FIG. 1 is a plan view of an array substrate of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a schematic plan view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 3 is a sectional view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 4 is a plan view of a conventional liquid crystal display device.

FIG. 5 is a sectional view of a conventional liquid crystal display device.

[Explanation of symbols]

1 Array substrate 2 Counter substrate 3 Sealant for liquid crystal sealing 3-a Liquid crystal sealing pattern 3-b Pattern that encloses the part cut by the laser 4 gate wiring 5 Source wiring 6 display area 7 cutting area 8 Gate wiring connection 9 LCD

Claims (4)

[Claims] 1. An array substrate in which a display pixel electrode is formed on an insulating transparent substrate through a thin film transistor and a gate wiring and a source wiring for driving the thin film transistor, and at least a part of the wiring is short-circuited outside a display region. A liquid crystal display device comprising: a counter substrate facing the array substrate via a gap; and a liquid crystal injected between the array substrate and the counter substrate. A sealant formed from the formed ring-shaped main seal portion for liquid crystal sealing and an annular sub-seal portion formed on the outer side thereof, and an area surrounded by the sub-seal portion is provided on the array substrate. A liquid crystal display device, characterized in that the wiring provided is cut off. 2. The liquid crystal display device according to claim 1, wherein the wiring is either a gate wiring or a source wiring. 3. A display pixel electrode is formed on an insulating transparent substrate via a thin film transistor and a gate wiring and a source wiring for driving the thin film transistor, and at least one of the gate wiring and the source wiring is short-circuited outside a display region, A ring-shaped main seal portion is formed around the display area of the array substrate and the counter substrate, and a ring-shaped sub-seal portion is formed at a wiring short circuit portion outside the display area, and the main portion between the array substrate and the counter substrate is formed. A method of manufacturing a liquid crystal display device, comprising injecting liquid crystal into a region surrounded by a seal portion, and cutting the wiring pattern short-circuited in the region surrounded by the sub seal portion. 4. An image display application device comprising the liquid crystal display device according to claim 1.