JP2001242486A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display device, in which the uniformity of images is enhanced by preventing degradation of characteristics of TFTs, while preventing UV (ultraviolet) light from being irradiated directly on semiconductor layers of the TFTs, at hardening of sealing agents of a liquid crystal pouring port. SOLUTION: Switching elements, consisting of thin-film transistors including respectively semiconductor layers 4, are arranged on one substrate of substrates holding a liquid crystal layer there-between, in response to plural pixel electrodes 10 and a video signal is supplied from video signal supplying wirings 5 to the plural pixel electrodes via the switching elements. A first pattern 7 which is formed with the same layer as that of scanning signal supplying wirings and a second pattern 8 which is formed with the same layer as that of the semiconductor layers 4 are arranged, so that an overlapped part of them exists in the vertical direction at the outer side of the switching elements along the substrate edge of a side, at which the switching elements become to be at an outer side with respect to the video signal supplying wirings.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active matrix type liquid crystal display device.

[0002]

2. Description of the Related Art A display device to which liquid crystal is applied has low power, light weight, and features not available in a conventional display. The display device is used for a notebook personal computer, a car navigation display, and the like since a clear image display with less crosstalk can be obtained, and has recently been rapidly used as a large display monitor.

Hereinafter, an example of a conventional active matrix type liquid crystal display device will be described with reference to the drawings. FIG. 2 is a schematic view of an array portion having a TFT of a conventional active matrix type liquid crystal display device. 1
Reference numeral 0 denotes a pixel electrode, and a plurality of pixels are arranged in a matrix. TFTs are arranged corresponding to the pixel electrodes 10. Reference numeral 2 denotes a scanning signal supply line, which also functions as a gate electrode of the TFTs arranged in a matrix,
The scanning signal is supplied to the gate electrode of the. Reference numeral 4 denotes an amorphous silicon semiconductor layer, which forms a channel region of the TFT. Reference numeral 5 denotes a video signal supply wiring, which also serves as a source electrode connected to the amorphous silicon semiconductor layer 4 of the TFT, and supplies a video signal to the pixel electrode 10 via the drain electrode 9.

FIG. 4 is a sectional view taken along the line AA 'in FIG. The scanning signal supply wiring 2 is formed on the glass substrate 1,
The first insulator layer 3 is stacked thereon to form a gate insulating film of the TFT. Reference numeral 6 denotes a passivation insulating film as a protective film.

The operation of the liquid crystal display device configured as described above will be described.

First, a voltage is applied to the scanning signal supply wiring 2 and the TFT is applied to the amorphous silicon semiconductor layer 4 of the TFT.
Channels are formed. Thereby, the video signal from the video signal supply wiring 5 passes through the channel of the TFT, flows into the drain electrode 9, and is transmitted to the pixel electrode 10. As a result, the orientation of the liquid crystal injected between the pixel electrode 10 and the counter electrode is arbitrarily changed by an electric field between the pixel electrode 10 and the counter electrode provided in the color filter portion facing the pixel electrode 10 in parallel. By adjusting the transmittance, a desired image is created.

In general, liquid crystal is injected according to the following procedure. An array substrate having an array portion and a color filter substrate having a counter electrode and a color filter are bonded together with a sealant. A part of the sealant is not applied beforehand, and this is used as a liquid crystal injection port. After the panels bonded in this state are evacuated, the liquid crystal is immersed in the injection port and returned to the atmospheric pressure as it is to inject the liquid crystal into the panel. Thereafter, a sealing agent is applied to the injection port, and the sealing agent is irradiated with ultraviolet rays (UV light) from a direction parallel to the panel to be cured.

[0008]

However, the structure of the above-mentioned conventional liquid crystal display device is particularly difficult in the step of irradiating and curing the sealing agent of the liquid crystal injection port with the UV light, particularly when the UV light is applied to the semiconductor layer of the video signal final line. Is irradiated and its TF
There is a possibility that the T characteristic may be degraded to cause an image defect of the liquid crystal display device.

The present invention solves the above-mentioned problem. As described above, UV light is directly applied to the TFT semiconductor layer,
It is an object to reduce image defects caused by deterioration of FT characteristics and improve image uniformity.

[0010]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and a liquid crystal is provided by disposing a guard pattern outside a final video signal line so that UV light is not directly radiated to a TFT semiconductor layer. In the step of irradiating and curing the sealing agent of the injection port with the UV light, the UV light is prevented from directly irradiating the TFT semiconductor layer, thereby preventing the TFT characteristics from deteriorating.

As a specific configuration, a liquid crystal display device of the present invention includes an insulating transparent substrate, a plurality of pixel electrodes arranged in a matrix on the transparent substrate, and a plurality of pixel electrodes corresponding to the plurality of pixel electrodes. A switching element each of which is arranged and a drain electrode is connected to the pixel electrode; a scanning signal supply line that forms a gate electrode of the switching element and supplies a scanning signal to the switching element; and a source electrode of the switching element. A video signal supply line that supplies a video signal to the plurality of pixel electrodes via the switching element; and an insulator layer that is stacked on the plurality of scanning signal supply lines and serves as a gate insulating film of the switching element. In each of the switching elements, the switching element is stacked on the insulator layer and electrically connects the source electrode and the drain electrode. It arranged comprised a thin film transistor array substrate and a semiconductor layer as one of the substrates so. A first pattern formed on the same layer as the scanning signal supply wiring, outside the switching element, along a substrate edge on a side where the switching element is on the outside with respect to the video signal supply wiring; The semiconductor layer and the second pattern formed on the same layer are arranged so that an overlapping portion exists in the vertical direction.

With this configuration, it is possible to prevent the UV light from being directly irradiated on the TFT semiconductor layer.

In the above configuration, the length of the overlapping portion of the first pattern and the second pattern is equal to the length of the range in which the switching element group connected to the video signal supply wiring adjacent to the overlapping portion is arranged. It is configured to be longer than this. Thereby, the UV light shielding is more complete.

Further, the first pattern can be formed on the same layer as the scanning signal supply wiring, and the second pattern can be formed on the same layer as the video signal supply wiring.

In the method for manufacturing a liquid crystal display device having the above-described structure, the first pattern can be formed in the same step as the step of forming the scanning signal supply wiring.
Thereby, an element for blocking UV light can be added without complicating the manufacturing process.

Further, the formation of the second pattern can be performed in the same step as the step of forming the semiconductor layer.
Alternatively, the formation of the second pattern can be performed in the same step as the step of forming the video signal supply wiring.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram of an active matrix type liquid crystal display device according to an embodiment of the present invention, and FIG. 3 is a sectional view taken along line AA 'in FIG. 2 and 4 showing the conventional example are denoted by the same reference numerals.

In FIG. 1, reference numeral 10 denotes a pixel electrode, a plurality of which are arranged in a matrix. TFTs are arranged corresponding to the pixel electrodes 10. Reference numeral 2 denotes a scanning signal supply line, which also serves as a gate electrode of the TFTs arranged in a matrix, and supplies a scanning signal to the gate electrode of the TFT. Reference numeral 4 denotes an amorphous silicon semiconductor layer, which forms a channel region of the TFT. Reference numeral 5 denotes a video signal supply wiring, which also serves as a source electrode connected to the amorphous silicon semiconductor layer 4 of the TFT, and supplies a video signal to the pixel electrode 10 via the drain electrode 9.

As shown in the sectional view of FIG. 3, the scanning signal supply wiring 2 is formed on a glass substrate 1 and a first insulator layer 3 is laminated thereon to form a gate insulating film of a TFT. Reference numeral 6 denotes a passivation insulating film as a protective film, which is made of, for example, SiNx, SiO2, acrylic resin, polyimide, polyamide, polycarbonate, or a laminated film thereof.

The configuration described above is the same as the conventional example shown in FIGS. 2 and 4, and the configuration of the present embodiment shown in FIGS. 1 and 3 is different from the configuration of FIGS. It is as follows. That is, U laminated on the glass substrate 1
A V shield gate layer pattern 7 and a UV shield amorphous silicon layer pattern 8 are provided. Both patterns 7 and 8 are arranged outside the TFT along the substrate edge on the side where the TFT is outside the video signal supply wiring 5. The UV shield gate layer pattern 7 is formed on the same layer as the scanning signal supply wiring 2. The UV shield amorphous silicon layer pattern 8 is formed in the same layer as the semiconductor layer 4. Both patterns 7 and 8 are arranged so that an overlapping portion exists in the vertical direction. Further, in the two patterns 7 and 8, the overlapping part of the patterns is connected to the video signal supply wiring 5 arranged on the side of the side where the two patterns 7 and 8 exist and the end of the substrate.
It is configured to be longer than the portion where the FT is arranged. Thus, in the step of irradiating and curing the sealing agent of the liquid crystal injection port with the UV light, it is possible to suppress the UV light from directly irradiating the TFT semiconductor layer and prevent the TFT characteristics from deteriorating.

In order to form an array substrate of a liquid crystal display device having such a configuration, first, a film for forming the scanning signal supply wiring 2 is deposited on a glass substrate 1 by a sputtering film forming method, followed by a photolithography step and an etching step. The patterning of the scanning signal supply wiring 2 is performed. By repeating the patterning of the thin film deposition, the photolithography process, and the etching process, the amorphous silicon semiconductor layer 4, the video signal supply wiring 5, the drain electrode 9, and the pixel electrode 10 are formed.

In this embodiment, the case where the semiconductor layer is used as the upper pattern constituting the overlapping portion has been described. However, the same effect can be obtained by using the video signal supply wiring instead of the semiconductor layer. Needless to say,

[0024]

As described above, according to the present invention, it is possible to prevent the UV light from directly irradiating the TFT semiconductor layer in the step of irradiating and curing the sealing agent for the liquid crystal injection port with the UV light. It is possible to reduce image defects caused in the final video signal line and improve image uniformity.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing a part of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a schematic plan view showing a part of a liquid crystal display device according to a conventional embodiment.

FIG. 3 is a sectional view showing a part of the liquid crystal display device in the liquid crystal display device of the present invention.

FIG. 4 is a cross-sectional view showing a part of a liquid crystal display device in a conventional liquid crystal display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass substrate 2 Scan signal supply wiring 3 Gate insulating film 4 Semiconductor layer 5 Video signal supply wiring 6 Passivation protection film 7 UV shield gate layer pattern 8 UV shield amorphous silicon layer pattern 9 Drain electrode 10 Pixel electrode

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H092 GA31 GA33 GA34 JA24 JA34 JB24 JB33 JB54 KA05 KA07 KA12 NA17 NA24 PA04 PA09 5C094 AA03 AA42 AA43 BA03 BA45 CA19 EA04 EB02 GB10 HA08 5F110 AA21 AA26 NN02NN03 NN27 NN80 QQ30

Claims (7)

[Claims] 1. An insulating transparent substrate, a plurality of pixel electrodes arranged in a matrix on the transparent substrate, and a drain electrode arranged corresponding to each of the plurality of pixel electrodes, a drain electrode connected to the pixel electrode. A switching element, a scanning signal supply line that forms a gate electrode of the switching element and supplies a scanning signal to the switching element, and a plurality of pixel electrodes that form a source electrode of the switching element and pass through the switching element. A video signal supply line for supplying a video signal to the plurality of scanning signal supply lines, an insulator layer laminated on the plurality of scan signal supply lines to serve as a gate insulating film of the switching element, and an insulating layer on each of the switching elements. And a semiconductor layer disposed so as to electrically connect the source electrode and the drain electrode. A liquid crystal display device having a transistor array substrate as one of the substrates, wherein the scanning signal is supplied to the outside of the switching element along an edge of the substrate on the side where the switching element is on the outside with respect to the video signal supply wiring. A liquid crystal display wherein a first pattern formed on the same layer as the wiring and a second pattern formed on the same layer as the semiconductor layer are arranged so as to have an overlap in the vertical direction. apparatus. 2. A length of an overlapping portion of the first pattern and the second pattern is longer than a length of a range in which a switching element group connected to the video signal supply wiring adjacent to the overlapping portion is arranged. 2. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is long. 3. The apparatus according to claim 1, wherein the first pattern is formed on the same layer as the scanning signal supply wiring, and the second pattern is formed on the same layer as the video signal supply wiring. The liquid crystal display device according to the above. 4. The method for manufacturing a liquid crystal display device according to claim 1, wherein the formation of the first pattern is the same as the step of forming the scanning signal supply wiring. A method for manufacturing a liquid crystal display device, comprising: 5. The method for manufacturing a liquid crystal display device according to claim 1, wherein the formation of the second pattern is performed in the same step as the step of forming the semiconductor layer. A method for manufacturing a liquid crystal display device, comprising: 6. The method for manufacturing a liquid crystal display device according to claim 3, wherein the formation of the second pattern is performed in the same step as the step of forming the video signal supply wiring. Of manufacturing a liquid crystal display device. 7. An image display application device comprising the liquid crystal display device according to claim 1. Description: