KR100228426B1 - Liquid crystal display elements and its manufacturing method - Google Patents

Abstract

An object of this invention is to provide a liquid crystal display element and its manufacturing method.

According to an embodiment of the present invention, a thin film transistor which transmits a signal of a data line when selecting a gate line, a pixel electrode contacted with a drain electrode of the thin film transistor, and driven when the thin film transistor is operated, is formed on the same substrate as the pixel electrode. And a counter electrode which induces an electric field parallel to the pixel electrode, the liquid crystal display device comprising: a space formed on top of the data line and a portion closest to the data line of the data line and the counter electrode in parallel with the data line; A barrier wall for blocking optical interference and a parasitic electric field is formed over a portion of the counter electrode and the counter electrode corresponding to the portion closest to the data line among the portions parallel to the data line in the counter electrode.

Description

Liquid crystal display device and manufacturing method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device and a manufacturing method thereof, and more particularly, to a liquid crystal display device and a method for manufacturing the same, which can block optical interference of a liquid crystal display device and realize high image quality.

In general, liquid crystal display elements constitute display elements such as televisions and graphic displays, and especially active matrix type liquid crystal display devices have high-speed response characteristics, and are suitable for high pixel counts, thereby making display screens of high quality, large size, and color screens. It greatly contributes to the realization of money.

The liquid crystal display device includes a pair of transparent glass substrates, thin film transistors and pixel electrodes formed on at least one substrate, a color filter and a counter electrode formed on the other substrate, and a liquid crystal material between the pair of glass substrates. This is done by encapsulation.

Here, as the liquid crystals used in recent years, a twist nematic mode (hereinafter referred to as TN) liquid crystal having excellent optical characteristics is used, and the twisted nematic mode has a twist angle of 90 °, and the liquid crystal molecules are upper and lower glass. Since they are arranged parallel to the substrate surface or the direction of arrangement differs by 90 ° on both substrates, the entire molecular array is arranged so that there is a continuous 90 ° change between the two substrates, and when a liquid crystal voltage is applied, the electric field It is formed perpendicular to the two substrate surfaces. However, the liquid crystal display of the TN structure has a chronic problem of narrowing the viewing angle.

Conventionally, in order to secure a wide viewing angle, as shown in FIG. 1, a counter electrode formed on an upper substrate is formed on a lower glass substrate on which a pixel electrode is formed, so that an electric field parallel to the pixel electrode is generated. In plane switching mode (hereinafter referred to as IPS mode) was used. The liquid crystal display of the IPS mode is formed on the same surface as the gate line 2A and the gate line 2A in the row direction for scanning an image on the lower substrate 1, and is spaced apart by a predetermined distance. Counter electrode 2B is formed. The counter electrode 2B also serves as a storage capacitor for maintaining the liquid crystal for a predetermined time, and the shape thereof is preferably formed in the shape of a " □ " to define a unit cell. A gate insulating film (not shown) is formed on the resultant, and a semiconductor layer 4 serving as a channel of the thin film transistor is positioned on a predetermined portion of the gate insulating film including the gate electrode wiring 2A. In the vertical form, the data line 5A and the pixel electrode 5B simultaneously serving as the drain electrode are formed. Here, the drain electrode 5B is formed in a “I” shape so as to vertically divide the space portion of the counter electrode 2B, which is formed in a “□” shape, and is parallel to the gate line 2A of the pixel electrode 5B. The portion to be overlapped with the counter electrode 2B in the portion parallel to the gate line 2A serves to serve as a storage capacitor.

In the conventional liquid crystal display of the IPS mode, as shown in FIG. 2, light incident from the backlight 100 on the rear surface of the lower substrate passes through the liquid crystal layer 10 and the color filters 21A, 21B, and 21C. do. However, in this process, the light passing through the liquid crystal layer 10 and the color filters 21A, 21B, and 21C is incident at a predetermined angle, and thus interference between R, G, and B colors is generated, as shown in the drawing. Color reproduction is difficult.

Further, in the conventional liquid crystal display of the IPS mode, as shown in FIG. 3, since the data line 5A and the counter electrode 2B are adjacent to each other, the parasitic electric field X is generated and the data line 5A is generated. A noise field (Y) is also generated between the pixel electrode 5B and the pixel electrode 5B, causing a phenomenon in which a signal is distorted between the pixel electrode 5B and the counter electrode 2B. Accordingly, the liquid crystals arranged between the pixel electrode 5B and the counter electrode 2B have a problem that it is difficult to operate ideally due to an unstable electric field.

Accordingly, it is an object of the present invention to provide a liquid crystal display device and a method of manufacturing the same, which can reproduce vivid colors by forming an interference blocking wall when light is transmitted through the liquid crystal display device to prevent light interference.

Another object of the present invention is to provide a stable electric field between the pixel electrode and the counter electrode by forming a barrier wall so that a parasitic electric field between the data line and the counter electrode and a noise electric field between the data line and the pixel electrode are not formed in the liquid crystal display device of the IPS mode. The present invention provides a liquid crystal display device and a method of manufacturing the same.

1 is a plan view showing a liquid crystal display device of the conventional IPS mode.

FIG. 2 is a cross-sectional view taken along line II-II 'of FIG. 1, showing a liquid crystal display of a conventional IPS mode when light is applied.

3 is a cross-sectional view of a liquid crystal display device showing an electric field distribution of a lower substrate when an electric field is applied to an electrode of a conventional IPS mode liquid crystal display device.

4 is a plan view of a liquid crystal display device according to the present invention.

5 (a) to 5 (c) are cross-sectional views of FIG. 4 taken along the line V-V 'in order to explain the manufacturing method of the liquid crystal display device according to the present invention.

6 is a cross-sectional view of a liquid crystal display device having a light interference blocking wall according to the present invention.

* Explanation of symbols for main parts of the drawings

1: glass substrate 2A: gate electrode wiring

2B: counter electrode 3: gate insulating film

4: semiconductor layer 5A: source electrode wiring

5B-1: Drain electrode 10: Liquid crystal

20: upper glass substrate 21A, 21B, 21C: color filter

100: backlight

In order to achieve the above object of the present invention, the liquid crystal display device of the present invention is contacted with the thin film transistor which transmits the signal of the data line and the drain electrode of the thin film transistor when the gate line is selected, and is driven during the operation of the thin film transistor. A liquid crystal display device comprising: a pixel electrode; and a counter electrode formed on the same substrate as the pixel electrode and inducing an electric field parallel to the pixel electrode, wherein the upper portion of the data line, the data line, and the data line; Blocks the optical interference and parasitic electric field over a predetermined portion of the counter portion corresponding to the data line among the parallel portions of the counter electrode and the portion closest to the data line among the parallel portions. It is characterized in that the barrier wall is arranged and formed.

In addition, the method of manufacturing a liquid crystal display device of the present invention comprises the steps of: forming a gate line and a counter electrode on a transparent glass substrate; Forming a gate insulating film on the glass substrate; Forming a semiconductor layer on an upper portion of the gate insulating film including the gate electrode wirings; Depositing and patterning the metal layer to form a pixel electrode connected to the data line and the semiconductor layer; Forming a first alignment layer on the resultant; rubbing the first alignment layer in a predetermined direction; Forming a second alignment layer on the first alignment layer; And forming a blocking wall by exposing and etching the second alignment layer so as to exist in a space between the data line and the counter electrode and a predetermined portion of the counter electrode.

According to the present invention, when applying light to a liquid crystal display element, in order to prevent optical interference and to minimize the parasitic electric field between the adjacent data line and the counter electrode and the noise electric field between the counter electrode and the drain electrode, the data line and the counter By forming a blocking wall over the space between the electrodes and above the predetermined portion of the counter electrode, the color is reproduced with clear high quality, the liquid crystal is driven stably, and the quality of the liquid crystal display element is improved.

EXAMPLE

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 4 is a cross-sectional view of the liquid crystal display device according to the present invention. FIGS. 5 (a) to 5 (c) are views illustrating the manufacturing method of the liquid crystal display device according to the present invention. 6 is a cross-sectional view of the liquid crystal display device in which the optical interference blocking wall according to the present invention is formed.

First, as shown in FIG. 4, the liquid crystal display of the present invention includes a gate line 2A in a row direction for scanning an image on the lower glass substrate 1 and a counter electrode for inducing a parallel field. 2B is formed of an opaque metal material on the same line as the gate line 2A. Here, the counter electrode 2B is formed in a "□" shape.

The data line 5A is formed to vertically intersect the gate line 2A, and the pixel electrode 5B, which forms the data line 5A and serves as a drain electrode, has the same structure as the conventional "I" shape. Is formed.

In addition, the blocking wall 40 for preventing optical interference and a noise electric field is formed on the upper portion of the data line 5A and in the portion of the data line 5A and the counter electrode 2B parallel to the data line 5A. A space portion formed of the portion closest to 5A and formed on the counter electrode 2A corresponding to the portion closest to the data line 5A among the portions parallel to the data line 5A in the counter electrode 2B. .

As described above, in the method of manufacturing the liquid crystal display device with the blocking wall 40-1, as shown in FIG. 5A, the gate line 2A, the counter electrode 2B, the data line 5A, and the drain electrode are provided. 5B is formed in the same manner as in the prior art, and an alignment film 30 for aligning the liquid crystal is formed on the resultant by a known method, and the alignment film 30 is rubbed so that the liquid crystal is driven in a predetermined direction.

Subsequently, as shown in FIG. 5 (b), in order to form a barrier wall, a low dielectric constant photosensitive alignment layer including black dye or pigment on the rubbed alignment layer 30 is preferably formed. The photosensitive alignment layer 40 having a dielectric constant of about 3.3 is formed at a thickness of about a cell gap, for example, about 1 to 10 μm.

Thereafter, the photosensitive alignment layer 40 having a low dielectric constant is formed on the upper portion of the data line 5A and the space between the counter electrode 2B and the counter electrode 2A, as shown in FIG. 5 (c). The barrier wall 40-1 is formed by exposing and etching by ultraviolet rays so as to exist above the predetermined portion.

Subsequently, the lower substrate 1 on which the blocking wall 40-1 is formed is bonded to the upper substrate 20 having the color filters 21A, 21B and 21C formed by a known method, and located on the lower substrate back surface. When the light is emitted from the backlight 100, the emitted light is blocked by the blocking wall 40-1, the light traveling toward the side at a predetermined angle, as shown in FIG. It doesn't work. Here, since the blocking wall 40-1 has a height as large as a cell gap, the blocking wall 40-1 comes into contact with the upper substrate when it is bonded with the upper substrate, thereby blocking light spreading to the side surface.

Referring to FIG. 6, when voltage is applied to the pixel electrode 5B and the counter electrode 2B, the blocking wall 40-1 is formed above the data line and above the predetermined portion of the counter electrode. A parasitic electric field between the line 5A and the counter electrode 2B and a noise electric field between the counter electrode 2B and the pixel electrode 5A are not generated, so that a stable electric field is formed.

As described in detail above, according to the present invention, when the light is applied to the liquid crystal display device, the optical interference is prevented, and the parasitic electric field between the adjacent data line and the counter electrode and the noise electric field between the counter electrode and the drain electrode are prevented. In order to minimize, by forming a blocking wall over the space between the data line and the counter electrode and over a predetermined portion of the counter electrode, a stable electric field is formed, and when the light is applied, the optical interference is blocked by the blocking wall, thereby providing a clear and high picture quality. The screen is obtained, and the quality of the liquid crystal display element is improved.

In addition, this invention can be implemented in various changes within the range which does not deviate from the summary.

Claims (9)

When the gate line is selected, a thin film transistor which transmits a signal of the data line, a pixel electrode which is in contact with the drain electrode of the thin film transistor and is driven when the thin film transistor is operated, is formed on the same substrate as the pixel electrode, A liquid crystal display device comprising a counter electrode for inducing a parallel electric field, the liquid crystal display device comprising: a space portion including an upper portion of the data line and a portion closest to the data line among the portions parallel to the data line in the data line and the counter electrode; And a blocking wall for blocking optical interference and parasitic electric fields over a predetermined portion of a counter electrode corresponding to a portion closest to the data line among the portions parallel to the data line. The liquid crystal display device of claim 1, wherein the blocking wall has a height of about 1 μm to about 10 μm. The liquid crystal display device of claim 1, wherein the blocking wall is formed of an alignment layer containing a black dye or a dye. The liquid crystal display device according to claim 1 or 3, wherein the barrier wall is formed of a photosensitive alignment layer having a low dielectric constant. The liquid crystal display device of claim 4, wherein the barrier wall has a dielectric constant of 3.0 to 3.3. Forming a gate line and a counter electrode on the transparent glass substrate; Forming a gate insulating film on the glass substrate; Forming a semiconductor layer on a predetermined portion of the gate insulating layer including the gate line; Depositing and patterning the metal layer to form a pixel electrode connected to the data line and the semiconductor layer; Forming a first alignment layer on the resultant; Rubbing the first alignment layer in a predetermined direction; Forming a second alignment layer on the first alignment layer; And exposing and etching the second alignment layer such that the second alignment layer exists in a space between the data line and the counter electrode and above a predetermined portion of the counter electrode to form a blocking wall. The method of claim 6, wherein the second realignment layer is deposited to a thickness of 1 to 10 μm. The method of claim 6, wherein the second alignment layer is a photosensitive alignment layer having a low dielectric constant including a black dye or a dye. The liquid crystal display device of claim 8, wherein the dielectric constant of the second alignment layer is 3.0 to 3.5.