JPH0823632B2 - Display device manufacturing method - Google Patents

Description

The present invention relates to a method for manufacturing a display device such as a liquid crystal display.

[Conventional technology]

5 and 6 are shown, for example, in JP-A-61-59475.
FIG. 11 is a front view showing a method of manufacturing a conventional display device disclosed in Japanese Patent Laid-Open No. 63-81975, in which (11) is a display electrode and a thin film transistor (hereinafter simply referred to as TFT) formed on a glass substrate. It is a TFT array substrate. (12)
Is a counter electrode substrate. Liquid crystal is filled between the TFT array substrate (11) and the counter electrode substrate (12). (13a) is a gate electrode wiring terminal, and (13b) is a source electrode wiring terminal. These wiring terminals (13a) and (13b) are the TFTs in the display area.
Are connected to the gate electrode and the source electrode, respectively. (1
4) is a short ring that short-circuits and connects all the gate electrode wiring terminals (13a) and the source electrode wiring terminals (13b).

Next, the manufacturing process will be described. The TFT array substrate (11) and the counter electrode substrate (12) are oriented by rubbing or the like. After the cell is assembled into the shape shown in FIG. 5 or 6, the liquid crystal is injected. During these processes, the short ring (14) keeps the potentials of all the gate electrodes and source electrodes of the TFTs at the same potential, and avoids deterioration or destruction of the TFT characteristics due to static electricity or the like. Then, as shown in FIGS. 5 and 6, A1-A
By cutting the TFT array substrate (11) along the 2, B1-B2, C1-C2, D1-D2 lines, the short ring (14) becomes a gate electrode wiring terminal (13a) and a source electrode wiring terminal (13b).
, And then the driving IC is mounted.

[Problems to be Solved by the Invention] In the conventional method for manufacturing a display device, as described above, the single short ring (14) is cut off and removed by cutting the substrate. A wide cutting width (E) is required, which is why the TFT array substrate (1
Not only the utilization efficiency of 1) is poor, but the width of the edge of the substrate at the time of liquid crystal injection becomes large, the injection yield deteriorates, and the depth of the liquid crystal tank used for injection deepens and adheres to the edge of the substrate. However, there is a problem in that the liquid crystal is used in large amounts and the liquid crystal utilization efficiency is low.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a method of manufacturing a display device that employs a short ring and has a narrow substrate end width during liquid crystal injection. .

[Means for Solving the Problems] In the method for manufacturing a display device according to the present invention, the short ring is doubled, and the outer thick short ring is removed by cutting the substrate after rubbing and before liquid crystal injection,
The thin inner short ring is designed to be removed by polishing the edge portion of the substrate after the liquid crystal is injected.

[Action]

The outer thick (low-resistance) short ring in this invention is caused by high-voltage static electricity generated during rubbing.
Prevents TFT characteristics from deteriorating, and the thin (relatively high resistance) short ring inside is caused by low voltage static electricity generated by liquid crystal cell handling such as liquid crystal injection.
Prevents deterioration of TFT characteristics.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. In FIG. 1, (11) is a TFT array substrate, (12) is a counter electrode substrate, (13a) is a gate electrode wiring terminal, and (13b) is a source electrode wiring terminal. It is the same as the one. (4) is an inner short ring, and (5) is an outer short ring, both of which are made of a conductor wiring material and connect / short-circuit all gate electrode wiring terminals (13a) and source electrode wiring terminals (13b). are doing. Inner short ring (4) is 100
It is formed with a thin pattern width of about μm, and the outer short ring (5) is formed with a thick pattern width of about 0.5 mm to 3 mm.

Next, the manufacturing process will be described. The formed and patterned TFT array substrate (11) is subjected to alignment treatment by rubbing after applying an alignment film. 500V ~ in the rubbing process
High-voltage static electricity of about 2KV is generated, but since the outer short ring (5) is formed with a thick pattern, it has low resistance, and the high-voltage static electricity with a large amount of charge can be easily conducted without delay time. Therefore, the potentials of all gate electrodes and source electrodes are kept at the same potential, and
TFT characteristic deterioration / destruction is avoided.

Subsequently, the cell is assembled by combining with the counter electrode substrate (12) similarly rubbed, and the static electricity generated in this step is also conducted mainly through the outer short ring (5) having a low resistance.

Next, the assembled liquid crystal panel (empty cell) is
The TFT array substrate (11) is cut along the lines A1-A2 and B1-B2 in FIG. 1, the outer short ring (5) is cut off and removed, and processed into the shape shown in FIG. Figure 3 is II of Figure 2.
It is an expanded sectional view of a portion along the line I-III. In the figure, (6) is a sealant, and (7) is a liquid crystal injected later. As shown in FIGS. 2 and 3, the cutting (A1-A2, B1-B2) of the substrate is performed in the immediate vicinity of the inner short ring (4).

Then, the liquid crystal (7) is injected. In the liquid crystal injection process. Only a relatively weak static electricity of about 50V to 200V is generated, and the static electricity is easily conducted even by the short ring (4) with a narrow pattern and high resistance, and all the gate and source electrodes are at the same potential. To be kept. Also,
The width (F) of the substrate edge at the time of liquid crystal injection is about 2 mm to 3 mm, which is only the length of the gate / source electrode wiring terminals (13a) and (13b), which is much shorter than the conventional one, so the injection yield is high. In addition, the liquid crystal tank used for injection may have a shallow depth, and at the same time, the amount of liquid crystal attached to the edge of the substrate is reduced, and the liquid crystal utilization efficiency is improved.

Finally, the inner short ring (4) is removed by removing (chamfering) the edge portion (1a) of the substrate edge by polishing, as shown in the chamfered portion (1b) of FIG. 4 (fourth).
Figure). Such a short ring removing method by polishing does not require a wide cutting width as in the conventional substrate cutting method, and therefore, the short ring removing method by polishing the end face corner portion is used, and the substrate during the injection as described above is used. The end width (F) can be shortened.

〔The invention's effect〕

As described above, according to the present invention, the short ring has a double structure of a thin inner short ring and a thick outer short ring, and the outer short ring is removed by cutting the substrate after rubbing, and the substrate is injected after liquid crystal injection. Since the inner short ring was removed by polishing the end face corners, the outer short ring
The TFT is protected from static electricity against the high voltage generated during rubbing, and the inner short ring can be used to prevent static electricity when injecting liquid crystal, but the board edge width can be reduced, improving the liquid crystal injection yield and liquid crystal utilization efficiency. Let
As a result, the yield and quality of the entire liquid crystal display can be improved.

[Brief description of drawings]

FIG. 1 is a view showing that a short ring is formed in a double manner according to the method of the present invention, and FIG. 2 is a view showing a state in which an outer short ring is cut and removed according to the method of the present invention, FIG. 3 is an enlarged view taken along section line III-III in FIG. 2, FIG. 4 is a view showing a state in which the inner short ring is removed by chamfering operation according to the method of the present invention, and FIG. FIG. 6 is a view showing a display device according to the manufacturing method of FIG. 6, and FIG. 6 is a partially enlarged view of FIG. In the figure, (11) is a TFT array substrate, (12) is a counter electrode substrate, (13a) is a gate electrode wiring terminal, (13b) is a source electrode wiring terminal, (4) is an inner short ring, and (5).
Is the outer short ring. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. In an active matrix type display device in which a thin film transistor is provided for each pixel, a short ring connected to all of the gate electrode wiring and the source electrode wiring of each thin film transistor is doubly provided around the display device substrate. 1. A method of manufacturing a display device, which comprises: a step of cutting and removing an outer short ring by cutting a substrate; and a step of removing an inner short ring by polishing a corner portion of a substrate end face.