JPH1195202A - Active matrix type liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to prevent the light leakage on the periphery of a display region while maintaining the spacing of an injection port part sufficient for liquid crystal injection by forming part of the light shielding layers in the region of the liquid crystal injection port of a metallic light shielding film. SOLUTION: The inter-substrate distance of an array substrate 11 and a counter substrate 12 is maintained by the insulative light shielding layers 15a of columnar projections as gap holding means. Plural signal lines and plural gate lines 17 are formed on the array substrate 11 in such a manner as to intersect with each other on the one main surface of the substrate. The metallic light shielding films 20 are simultaneously formed in the parts which constitute the liquid crystal injection port and the places which are shieldable of light by the metallic films. TFTs as driving elements 21 for switching and pixel electrodes 22 electrically connected thereto are formed at each of the intersecting parts of the signal lines and the gate lines 17. The smooth injection is executed by the injection port structure having the spacing sufficient for injection of the liquid crystals in such a manner and the light leakage from the peripheral parts is lessened. A high contrast ratio and a good-quality display are obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an active matrix type liquid crystal display device.

[0002]

2. Description of the Related Art Active matrix display devices using liquid crystals are characterized by being thin and lightweight, and have become one of the representative display devices for TV and OA equipment.

FIG. 7 schematically shows a general active matrix type display device. 0.1μ on transparent counter substrate 41
a light-shielding layer 42 formed by patterning a Cr metal film of m in a predetermined shape and a coloring layer 43 constituting a color filter in an opening of the light-shielding layer 42 by a pigment dispersion method, an electrodeposition method, a printing method, and the like. A common electrode 44 made of ITO is provided, and an alignment film 45 made of polyimide is provided thereon.

A thin film transistor (TF) is formed on one transparent array substrate 46 at a position facing the light shielding layer 42.
T) A drive element made of 47 is provided, an ITO pixel electrode 48 is provided at a position corresponding to the opening of the light shielding layer 42, the pixel electrode and the TFT 47 are electrically connected, and an alignment film 49 made of polyimide is formed thereon. Is provided on the entire surface.

A liquid crystal 50 is sandwiched between these two substrates, and a polarizing plate is attached to the outside of the two substrates. The gap between the two substrates is kept constant by the spacer 51. In this device, by switching the TFT 47 and applying a video signal to the pixel electrode 48 to control the orientation of the liquid crystal 42 and modulate the light transmitted through the colored layer 43, the device can be used as a display device.

[0006]

In the conventional device, in order to prevent light leakage from the periphery of the pixel electrode 48 and light from entering the TFT 47, the light shielding layer 42 on the counter substrate 41 is provided with an array substrate 46.
Are formed corresponding to regions other than the pixel electrode 47.
However, misalignment between the substrates 41 and 46, the light-shielding film 42 and T
The light shielding layer 4 as a margin for the pitch shift of the FT 47
2 is designed to be wider so as to cover the periphery of the pixel electrode. Therefore, there is a disadvantage that the opening of the light-shielding film becomes small and the luminance of the display device is reduced.

As a structure for compensating for this disadvantage, a light-shielding film and a coloring layer serving as a color filter layer are provided on or below the pixel electrodes 48 of the array substrate 46 on which the TFTs are disposed, and only the common electrode is disposed on the transparent substrate on the opposite substrate. A liquid crystal display device has been proposed.

However, in this improved liquid crystal display device, since a conductive light-shielding film is not used for insulation between pixels, it is necessary to use a material having a high insulating property.
It is difficult to obtain a sufficient light-shielding property with a material having a high insulating property, and in order to obtain a practical light-shielding property, it is necessary to increase the thickness of both inorganic and organic materials. In addition, if a gap holding material for maintaining the gap between the two substrates is formed at the same time as the light-shielding layer using this highly insulating material, the number of steps can be reduced and the image quality can be improved. However, in these cases, the peripheral light-shielding film formed at the liquid crystal injection port has a large thickness, so that it is difficult to provide a sufficient gap for liquid crystal injection.

SUMMARY OF THE INVENTION It is an object of the present invention to prevent light leakage around a display area while maintaining a sufficient gap at an injection port for liquid crystal injection.

[0010]

According to the present invention, there is provided an array substrate having pixel electrodes and driving elements connected thereto arranged in a matrix, a counter substrate having a common electrode opposed to the pixel electrodes, and an array substrate. A sealing material for providing a gap between the substrate and the counter substrate and sealing, a liquid crystal injection port formed in a part of the sealing material region, and a liquid crystal sealed in the gap,
In an active matrix type liquid crystal display device including an insulating light-blocking layer provided on the array substrate side so as to surround the pixel electrode, a part of the light-blocking layer in a region of the liquid crystal injection port is a metal light-blocking film or the light-blocking layer. An active matrix type liquid crystal display device is provided which is formed on at least a part of the counter substrate facing the layer.

Further, an active matrix type liquid crystal display device characterized in that an antireflection layer is provided on at least a part of the metal light shielding film.

Further, the present invention provides an active matrix type liquid crystal display device comprising at least one color filter layer as the antireflection layer.

[0013] Further, the semiconductor device has a signal line and a gate line formed of metal on the array substrate and is connected to the driving element, and the metal light shielding film is formed simultaneously with the signal line or the gate line. An active matrix type liquid crystal display device characterized by the following is obtained.

Further, a cut is provided in a part of the metal light-shielding film, and a black resin is formed in the cut, thereby obtaining an active matrix type liquid crystal display device.

Further, an active matrix type liquid crystal display device is provided, wherein a cut is formed in a part of the metal light shielding film, and a transparent conductive film is formed in the cut.

According to the present invention, in a structure in which an insulating light-shielding layer such as an organic film is formed on an array substrate side, an injection port region is formed by vapor deposition.
Light is shielded by a thin metal film formed by sputtering or the like, and the area where the metal film is difficult to form is made of a colored resin such as black, so that the liquid crystal is injected without any additional steps. A sufficient gap for the operation can be secured.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) Hereinafter, an embodiment of the present invention will be described. As shown in FIGS. 1 to 3, the liquid crystal display device 10 according to the present embodiment has a liquid crystal layer 13 sandwiched in a gap between an array substrate 11 and a counter substrate 12, and is formed on the outer peripheral portion of the array substrate 11 and the counter substrate 12. The two substrates are adhered to each other by the sealing material 14, and the distance between the array substrate 11 and the opposing substrate 12 is held by an insulating light-shielding layer 15a of columnar projections as gap holding means.

A plurality of signal lines 16 and a plurality of gate lines 17 are formed on one main surface of the array substrate 11 so as to intersect with each other.
The metal light-shielding film 20 is formed in a place where light can be shielded by the metal film.
At each intersection of the signal line 16 and the gate line 17, a TFT and a pixel electrode 22 electrically connected to the TFT are formed as switching drive elements 21.

More specifically, a gate electrode extending from the gate line 17 is provided on the substrate 11, and a semiconductor layer 23 made of p-Si is formed on the gate electrode via a gate insulating film. A silicon oxide film and a silicon nitride film (not shown) serving as a passivation film are formed. Through holes are formed in the silicon oxide film and the silicon nitride film, and the drain electrode and the source electrode are electrically connected to the semiconductor 23. Cover these,
An organic insulating film 25 (blue colored layer 25B in the figure) such as an acrylic resin serving as a colored layer forming a color filter also serving as an interlayer insulating film is formed, and a through hole is formed on the drain electrode of the insulating film 25. The drain and the pixel electrode 22 are connected via the through hole.

That is, the organic insulating film 25 has a red layer in which a red pigment is dispersed with an ultraviolet curable acrylic resin resist (CR-2000, Fuji Hunt Technology Co., Ltd.).
Is coated on the entire surface with a spinner, and 365 n is applied through a photomask that irradiates light to a portion to be colored red.
Irradiation at a wavelength of 100 mJ / cm ² , development with a 1% aqueous solution of KOH for 10 seconds, and baking at 230 ° C. for 1 hour to form a 2.0 μm-thick red colored layer (27R).

Similarly, a green layer and a blue layer 25B are repeatedly formed and baked at 230 ° C. for 1 hour. Here, a green coloring material (CG-2000, manufactured by Fuji Hunt Technology Co., Ltd.) and a blue colored layer (CB-2000, manufactured by Fuji Hunt Technology Co., Ltd.) were used.

The blue colored layer 25B is also formed as an antireflection film on the metal light-shielding film 20 at the liquid crystal injection port, and forms a peripheral light-shielding portion at the injection port. When the blue colored layer is an anti-reflection film, the reflected light is inconspicuous because of blue, and is superior to the red and green colored layers.

Next, a photosensitive black resin is applied using a spinner, dried at 90 ° C. for 10 minutes, and then dried at 300 nm at a wavelength of 365 nm using a photomask having a predetermined pattern shape.
After exposure at an exposure amount of mJ / cm ² , development was performed with an alkaline aqueous solution having a pH of 11.5, and baking was performed at 200 ° C. for 60 minutes to form a 5.0 μm-thick black insulating light-shielding layer 15 on the gate line 17 and Similarly, the peripheral light-shielding layer 15 is formed so as to surround the display area 27 in which the pixel electrodes are arranged in a matrix. The light-shielding layer 15a on the gate line 17 also functions as a gap holding material.
This light-shielding layer 15 is not formed in the portion where the metal light-shielding film exists at the injection port.

After that, an ITO film is used as the transparent electrode 22.
A film was formed to a thickness of 500 A (angstrom) by a sputtering method.

The drain electrode of the TFT has the above-mentioned R, G,
A negative resist containing a pigment of B is connected to a pixel electrode 22 made of ITO in contact with a colored layer 25 patterned by photolithography. A similar alignment film material (AL-1051, manufactured by Nippon Synthetic Rubber Co., Ltd.)
After forming 00A (angstrom), a rubbing process was performed to form an alignment film 26. Thereafter, the sealing material 14 is printed along the periphery of the alignment film 26 of the substrate 11 except for the liquid crystal injection port 18, and an electrode transfer material (not shown) for applying a voltage from the array substrate 11 to the common electrode 30. ) Was formed on an electrode transfer electrode (not shown) around the sealing material.

A substrate 12 facing the array substrate 11 is a transparent substrate on which a 0.15 μm-thick I5
A TO film is formed, and an alignment film 3 made of polyimide is formed thereon.
Form one.

Next, the substrate 11, the orientation films 26 and 31 are opposed to each other, and the rubbing directions are 90 degrees.
12 is arranged and heated to cure the adhesive, and the substrates 11, 1
2 were pasted together.

Next, the liquid crystal 13 is injected from the injection port by an ordinary method.
As S81 in ZLI-1565 (E. Merck)
1 was added in an amount of 0.1 wt%, and then the injection port 18 was sealed with a sealing material 32 made of an ultraviolet curable resin.

Further, the polarizing plate 2 is provided on both surfaces of the substrates 11 and 12.
8, 29 were pasted.

In the color display type active matrix liquid crystal display device thus formed, smooth injection is performed by an injection port structure having a sufficient gap for injecting liquid crystal. Halved. In addition, light leakage from the peripheral portion was small, the contrast ratio was high, and high quality display was obtained.

The antireflection film on the metal light-shielding film 20 at the injection port may be formed of any number of appropriate materials such as a plurality of different color filter coloring layers.

The anti-reflection film may be formed at a position facing the metal light-shielding film 20 on the counter electrode side. Further, the antireflection film can be omitted.

Further, the pixel electrode 22 may be located on the upper or lower side of the colored layer 25.

The coloring layer 25 may be formed on either the array substrate or the counter substrate. Further, the method for forming the colored layer is not limited to the photolithography method of the pigment resist, and a known method such as a dyeing method, a printing method, and an electrodeposition method can be used.

(Embodiment 2) This embodiment is shown in FIGS. 4 and 5. The same reference numerals as those described in the first embodiment of FIGS. 1 to 3 denote the same parts.

This embodiment differs from the first embodiment in the structure of the liquid crystal injection port 18. Metal light shielding film 20a
Are formed in the liquid crystal injection port 18 by sputtering in the same material and in the same process as the metal film constituting the gate line. As shown in FIG. 4, the planar pattern of the metal light-shielding film 20a has a plurality of rectangular cuts 33 formed on the image display side. It is preferable that the cut has an area ratio of 1/2 or less with respect to the entire light shielding layer including the metal film at the injection port. After the blue colored film 25B is formed thereon, the ITO is formed to a thickness of 1500A over the rectangular portion simultaneously with the formation of the pixel electrode 22.
The conductive film 34 is formed by sputtering. This conductive film is connected to a circuit (not shown) in which a liquid crystal drive voltage is constantly applied to the common electrode 30 on the counter substrate 12. That is,
The metal light shielding film functions as a lead of the common electrode 30. The organic light-shielding film 15 is not formed near the injection port 18. Due to the structure of the thin metal film 20a, the opening of the liquid crystal injection port 18 is sufficiently ensured, and no trouble occurs in the liquid crystal injection step. The metal light-shielding film can prevent light leakage, and the blue coloring film 25B functions as an anti-reflection film for light reflection by the film.

(Embodiment 3) This embodiment is shown in FIG. The same reference numerals as in the first embodiment denote the same parts.

The difference between the present embodiment and the second embodiment resides in that the black resin layer 15b is formed in the cut portion 33 of the metal light shielding film 22a.

The black resin layer 15b includes a light-shielding layer 15a serving as a gap holding material and a peripheral light-shielding layer 15 around the display area.
Are formed at the same time in the same insulating material and in the same step, and are provided in the portion excluding the portion where the metal light shielding film is formed, that is, in the cut portion 33.

The thickness of the black resin layer 15b is the same as that of the gap holding material, that is, 5 μm, and the injected liquid crystal mainly fills the gap by passing over the metal light shielding film between the columns of the black resin layer 15b.

In the vicinity of the injection port 18, the metal light shielding film 20a and the black resin layer 15b function as a part of the peripheral light shielding film,
Further, the blue resin layer 15b functions as an antireflection film of the metal light shielding film 20a. Further, the same effect can be obtained by providing a plurality of appropriate materials such as laminating different color filter coloring layers on a plurality of layers instead of the black resin layer 15b.

Although the present invention has been described with reference to the embodiment, the present invention is particularly suitable for the operation of applying a voltage between the pixel electrode and the common electrode to perform black display.

[0043]

According to the present invention, when a frame-shaped peripheral light-shielding layer is formed around the display area at the same time as the formation of the gap holding material, most of the light-shielding layer at the injection port, which hinders liquid crystal injection, is made of a metal film. By forming, it is possible to prevent light leakage around the display area / area while maintaining a sufficient gap at the injection port portion for liquid crystal injection without increasing the number of steps.

[Brief description of the drawings]

FIG. 1 is a plan view of a liquid crystal display device showing an embodiment of the present invention and schematically showing the arrangement of pixel electrodes;

FIG. 2 is a partially enlarged plan view of FIG. 1;

FIG. 3 is an enlarged sectional view taken along line AA of FIG. 2;

FIG. 4 is a partially enlarged plan view of a liquid crystal display device showing another embodiment of the present invention;

FIG. 5 is an enlarged sectional view taken along line AA of FIG. 4;

FIG. 6 is a partially enlarged cross-sectional view of a liquid crystal display device according to another embodiment of the present invention;

FIG. 7 is a partial cross-sectional view of a conventional liquid crystal display device.

[Explanation of symbols]

 10: Liquid crystal display device 11: Array substrate 12: Counter substrate 13: Liquid crystal 14, 32 Sealing material 15: Black resin layer 15a: Black resin layer serving as a gap holding material 16: Signal line 17: Gate line 18: Injection port 20 Reference numeral 20a: Metal (light shielding) film 21: Driving element (TFT) 22: Pixel electrode 25: Colored layer 30: Common electrode 33: Notch

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yasuharu Tanaka 8 Shinsugita-cho, Isogo-ku, Yokohama, Kanagawa Prefecture Inside the Toshiba Yokohama Office (72) Inventor Masumi Manabe 8 Shinsugita-cho, Isogo-ku, Yokohama, Kanagawa (72) Inventor Takeshi Yamamoto 1-9-2 Hara-cho, Fukaya-shi, Saitama Prefecture Inside the Toshiba Fukaya Electronics Factory (72) Inventor Teruyuki Midorikawa 7-1, Nisshincho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Inside Toshiba Electronic Engineering Co., Ltd. (72) Inventor Yoshiro Aoki Eighteen Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Inside Toshiba Yokohama Office (72) Inventor Yasuyuki Hanazawa Eighth Shin-Sugita-cho, Isogo-ku, Yokohama-shi, Kanagawa (72) Inventor Masaki Miyatake 8 Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa Formula company Toshiba Yokohama workplace (72) inventor Shoichi Kurauchi Saitama Prefecture Fukaya Hatara-cho, chome No. 9 No. 2 stock company Toshiba Fukaya in an electronic factory

Claims (6)

[Claims] An array substrate on which pixel electrodes and driving elements connected thereto are arranged in a matrix; a counter substrate on which a common electrode facing the pixel electrodes is formed; and a gap between the array substrate and the counter substrate. Sealing material, a liquid crystal injection port formed in a part of the sealing material region, liquid crystal sealed in the gap portion, and provided on the array substrate side to surround the pixel electrode. An active matrix liquid crystal display device comprising an insulating light-shielding layer, wherein a part of the light-shielding layer in a region of the liquid crystal injection port is formed of a metal light-shielding film. 2. The anti-reflection layer according to claim 1, wherein an anti-reflection layer is provided on at least a part of the light-shielding layer on the metal light-shielding film or on at least a part of the counter substrate facing the light-shielding layer. An active matrix type liquid crystal display device as described above. 3. The liquid crystal display device according to claim 2, wherein at least one color filter layer is provided as the antireflection layer. 4. An array substrate having signal lines and gate lines formed of metal on the array substrate and connected to the drive element, wherein the metal light-shielding film is formed simultaneously with the signal lines or gate lines. The liquid crystal display device according to claim 1, wherein 5. The liquid crystal display device according to claim 1, wherein a cut is provided in a part of the metal light shielding film, and a black resin is formed in the cut. 6. A liquid crystal display device, wherein a cut is formed in a part of the metal light shielding film, and a transparent conductive film is formed in the cut.