JP2005114887A - Liquid crystal display device and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device in which a product yield is improved and a method for manufacturing the same. <P>SOLUTION: The liquid crystal display device is provided with a TFT substrate 2 on which a plurality of pixels are disposed in a matrix, a transparent substrate 7 stuck to the TFT substrate by using a transparent adhesive, a counter substrate 6 placed opposite to the transparent substrate via a specified interval and a liquid crystal 8 held in a gap between the transparent substrate and the counter substrate. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a liquid crystal display device and a manufacturing method thereof. Specifically, the present invention relates to a liquid crystal display device having a structure in which a liquid crystal material is held between a pair of opposing substrates and a method for manufacturing the same.

In recent years, with the spread of electronic devices with a liquid crystal display device typified by a liquid crystal projector and the like, the demand for higher performance of the liquid crystal display device has increased, and in order to increase the definition and brightness of the liquid crystal display device Various improvements have been made. Here, a liquid crystal panel used for a liquid crystal display device generally includes a TFT substrate, a color filter, a black matrix, and the like on which pixel portions arranged in a matrix, thin film transistors for pixel control (hereinafter referred to as TFTs), and the like are formed. The counter substrate on which is formed is bonded using a sealing material, and liquid crystal is injected and sealed in the gap between the TFT substrate and the counter substrate.
Hereinafter, a conventional method for manufacturing a liquid crystal display device will be described with reference to the drawings.

In the conventional method of manufacturing a liquid crystal display device, first, as shown in FIG. 3A, a liquid crystal driving circuit (not shown) such as a TFT circuit is formed, and the pixel electrodes 101 are arranged in a matrix. An alignment film 103 is formed on the TFT substrate 102 made of quartz, silicon, or the like, and an alignment process is performed.
Next, as shown in FIG. 3B, the transparent substrate 107 is formed on the surface, the alignment film 103 is formed on the transparent electrode, and the counter substrate 104 made of quartz glass or the like subjected to alignment treatment. And the TFT substrate are bonded together using a sealant 105.
Subsequently, by injecting and sealing the liquid crystal 106 in the gap between the TFT substrate and the counter substrate, a liquid crystal display device as shown in FIG. 3C is obtained, and then the final inspection of the manufactured liquid crystal display device is performed. (For example, see Patent Document 1).

JP-A-8-234215

However, in the above-described method for manufacturing a liquid crystal display device, an alignment film is directly formed on a substrate on which a liquid crystal driving circuit such as a TFT circuit is formed, and then a counter substrate is bonded using a sealing material. Liquid crystal is injected and sealed between the two, and there is a problem that a non-defective product of the liquid crystal drive circuit becomes a defective product due to an abnormality in the liquid crystal assembly process.
That is, even if the liquid crystal drive circuit is a good product, if an abnormality occurs in the liquid crystal assembly process, the liquid crystal display device becomes a defective product.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a liquid crystal display device and a method for manufacturing the liquid crystal display device that can improve the product yield.

  In order to achieve the above object, a liquid crystal display device according to the present invention includes a first substrate in which a plurality of pixels are arranged in a matrix, a second substrate bonded to the first substrate, A third substrate disposed facing the second substrate via a predetermined gap; and a liquid crystal held in the gap between the second substrate and the third substrate.

  Here, the liquid crystal region and the pixels formed in a matrix on the first substrate can be separated from each other by the second substrate bonded to the first substrate.

  In order to achieve the above object, a method for manufacturing a liquid crystal display device according to the present invention includes a first substrate in which a plurality of pixels are arranged in a matrix and a first substrate that is bonded to the first substrate. A liquid crystal display device comprising: a second substrate; and a third substrate disposed facing the second substrate with a predetermined gap between the second substrate and the third substrate. Forming a seal pattern on a peripheral portion of the second substrate or the third substrate so that at least one opening is formed when the substrates are bonded, the second substrate, the third substrate, Bonding the liquid crystal into the gap between the second substrate and the third substrate through the opening, and bonding the first substrate and the second substrate. With.

Here, a liquid crystal display unit can be formed by injecting and sealing liquid crystal in a gap between the second substrate and the third substrate.
In addition, by bonding the first substrate and the second substrate, the liquid crystal display portion and the substrate on which the liquid crystal driving circuit is formed can be integrated.

  In the liquid crystal display device to which the present invention is applied and the manufacturing method thereof, a good product of the liquid crystal display unit and a good product of the substrate on which the liquid crystal driving circuit is formed can be combined, so that the product yield can be improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings to provide an understanding of the present invention.
FIG. 1 is a schematic cross-sectional view for explaining a reflective liquid crystal display device which is an example of a liquid crystal display device to which the present invention is applied. The reflective liquid crystal display device 1 shown here is a liquid crystal driving device such as a TFT circuit. A TFT substrate 2 made of a silicon substrate on which a circuit is formed and a liquid crystal display unit 3 are formed.

  Here, the TFT substrate has pixel electrodes 4 made of aluminum or the like formed in a matrix.

  In the liquid crystal display unit, a liquid crystal 8 is held in a gap between a counter substrate 6 made of quartz glass having a thickness of about 1 mm and a transparent substrate 7 made of quartz glass having a thickness of about 0.4 mm bonded together by a sealing material 5. The structure is adopted. Here, in the counter substrate, a transparent electrode 9 made of ITO (indium-zinc oxide based transparent conductive film) or the like is formed on the liquid crystal side surface, an alignment film (1) 10 is formed on the transparent electrode, and an alignment treatment is performed. Is given. Further, the transparent substrate is subjected to an alignment treatment by forming an alignment film (2) 11 on the liquid crystal side surface.

  Here, it is sufficient for the transparent substrate to be able to separate the liquid crystal display unit and the liquid crystal drive circuit unit, and the thickness is not necessarily 0.4 mm. However, image display by a liquid crystal display device is performed by applying a voltage to the pixel electrode and the transparent electrode, and controlling the light transmittance based on the birefringence characteristics of the liquid crystal substance held in the gap between the counter substrate and the transparent substrate. Therefore, it is necessary to form it with a thickness that does not adversely affect the control of light transmittance.

  In the reflective liquid crystal display device to which the present invention is applied, a good product of the liquid crystal display unit and a good product of the TFT substrate on which the liquid crystal driving circuit is formed can be combined, so that the product yield can be improved.

Further, it is possible to suppress the disorder of the alignment of the liquid crystal due to the pixel groove which is a gap between the outermost surface of the pixel electrode and the outermost surface of the pixel electrode.
That is, the liquid crystal driving circuit is flat and the liquid crystal driving circuit is not formed as compared with the conventional reflective liquid crystal display device in which the alignment film is formed on the uneven TFT substrate and the alignment process is performed. Since the alignment film (2) is formed on the transparent substrate and subjected to the alignment treatment, the disorder of the alignment of the liquid crystal can be suppressed, and “brightness” is one of the important performance elements for the liquid crystal display device. "And the image quality can be improved.

Further, the width of the pixel groove can be made very narrow.
In other words, with regard to the reduction of the width of the pixel groove, the limit of the manufacturing process has been evolving year by year, and even processing up to several tens of nanometers has become possible. However, liquid crystal molecules enter the pixel groove, resulting in disturbance of the liquid crystal alignment. In the conventional reflective liquid crystal display device, the pixel groove has a certain width, but in the reflective liquid crystal display device to which the present invention is applied, liquid crystal molecules may enter the pixel groove. Therefore, the width of the pixel groove can be made very narrow, and the width of the pixel groove can be made very narrow, that is, the area of the pixel electrode can be increased, thereby improving the reflectance of the pixel electrode. Thus, “brightness” can be improved and response speed can be improved.

  FIG. 2 is a schematic cross-sectional view for explaining a method for manufacturing a transmissive liquid crystal display device, which is an example of a method for manufacturing a liquid crystal display device to which the present invention is applied. In the method of manufacturing a transmissive liquid crystal display device to which the present invention is applied, first, an alignment film (2) 11 is formed on a transparent substrate 7 made of quartz glass having a thickness of about 0.4 mm as shown in FIG. An orientation process is performed.

  Next, as shown in FIG. 2B, a transparent electrode 9 made of quartz glass having a thickness of about 1 mm and made of ITO or the like is formed on the surface, and an alignment film (1) 10 is formed on the transparent electrode. In addition, a pattern of the sealing material 5 is formed so that one opening is formed in the peripheral portion of the counter substrate 6 that has been subjected to the alignment treatment, and the counter substrate 6 and the transparent substrate 7 are bonded together to form a liquid crystal display unit. Form.

  Next, as shown in FIG. 2C, liquid crystal 8 is injected and sealed in the gap between the counter substrate 6 and the transparent substrate. Thereafter, the TFT substrate 2 and the liquid crystal display unit 3, which are made of quartz glass on which a liquid crystal driving circuit such as a TFT circuit is formed and transparent pixel electrodes 12 made of ITO or the like are formed in a matrix, are bonded together with a transparent adhesive. Thus, the transmissive liquid crystal display device 13 can be obtained.

  In the method of manufacturing a transmissive liquid crystal display device to which the present invention is applied, a good product of the liquid crystal display unit and a good product of the TFT substrate on which the liquid crystal driving circuit is formed can be combined, so that the product yield can be improved. In addition, it is possible to suppress disturbance in the alignment of the liquid crystal due to the pixel groove, and it is possible to make the width of the pixel groove very narrow.

It is typical sectional drawing for demonstrating an example of the liquid crystal display device to which this invention is applied. It is typical sectional drawing for demonstrating an example of the manufacturing method of the liquid crystal display device to which this invention is applied. It is typical sectional drawing for demonstrating the manufacturing method of the conventional liquid crystal display device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reflective type liquid crystal display device 2 TFT substrate 3 Liquid crystal display part 4 Pixel electrode 5 Sealing material 6 Opposite substrate 7 Transparent substrate 8 Liquid crystal 9 Transparent electrode 10 Alignment film (1)
11 Alignment film (2)
12 Transparent pixel electrode 13 Transmission type liquid crystal display device

Claims (2)

A first substrate having a plurality of pixels arranged in a matrix;
A second substrate bonded to the first substrate;
A third substrate disposed facing the second substrate via a predetermined gap;
A liquid crystal display device comprising: a liquid crystal held in a gap between the second substrate and the third substrate. A first substrate on which a plurality of pixels are arranged in a matrix, a second substrate bonded to the first substrate, and a third substrate arranged to face the second substrate via a predetermined gap A method for manufacturing a liquid crystal display device comprising:
Forming a seal pattern on the periphery of the second substrate or the third substrate so that at least one opening is formed when the second substrate and the third substrate are bonded together;
Bonding the second substrate and the third substrate;
Injecting and sealing liquid crystal into the gap between the second substrate and the third substrate from the opening;
The manufacturing method of a liquid crystal display device provided with the process of bonding the said 1st board | substrate and the said 2nd board | substrate.

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