KR100895310B1 - Thin film transistor array panel - Google Patents

Abstract

The thin film transistor substrate according to the present invention includes a transparent insulating substrate, a gate wiring formed on the insulating substrate, a gate insulating layer formed on the gate wiring, a semiconductor layer formed on the gate insulating layer to form a channel, and a predetermined region of the semiconductor layer. Except for a resistive contact layer formed in the same planar pattern as the semiconductor layer, a data wiring formed on the ohmic contact layer, a protective layer formed on the data wiring and having a contact hole exposing a predetermined area of the data wiring, protective layer A pixel electrode formed thereon and connected to the data wiring through the contact hole, the pixel electrode including a plurality of small portions, and projections formed between the small portions, wherein the portions and the projections of the data wiring are formed of a first metal pattern and The third metal pattern is formed to surround the second metal pattern, and the data wiring The part except the part and the protrusion is a double layer of the first metal pattern and the third metal pattern.

LCD, thin film transistor substrate, sustain electrode, electric field, domain

Description

Thin film transistor array panel

1A is a layout view of a thin film transistor substrate according to the present invention.

FIG. 1B is a cross-sectional view taken along line Ib-Ib 'of FIG. 1A.

2A through 6A are cross-sectional views sequentially illustrating a method of manufacturing a thin film transistor substrate according to the present invention.

2B to 6B are cross-sectional views of each cut line of FIGS. 2A to 6B.

7A is a layout view of a color filter substrate according to the present invention.

FIG. 7B is a cross-sectional view taken along the line VIIb-VIIb ′ of FIG. 7A.

8 is a layout view of a liquid crystal display according to the present invention.

※ Brief description of the main parts of the drawings ※

110: substrate 121, 123: gate wiring

131, 133a, 133b, 133c, and 133d: sustain electrode wiring

150, 151, 153: semiconductor layer 161, 163, 165: ohmic contact layer

171a, 171b, 171c, 173a, 173c, 175a, 175c: data wiring

190a, 190b, 190c, 190d, 191a, 191b: pixel electrode

280a, 280b, 280c: protrusion

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to thin film transistor substrates for liquid crystal displays, and more particularly, to thin film transistor substrates that divide a pixel region into a plurality of small domains in order to obtain a wide viewing angle.

In general, a liquid crystal display device injects a liquid crystal material between a color filter substrate on which a reference electrode and a color filter are formed, and a thin film transistor substrate on which a thin film transistor and a pixel electrode are formed. By applying different potentials to the electric field to form an electric field to change the arrangement of the liquid crystal molecules, and through this to control the light transmittance is an apparatus that represents the image. At this time, a polarizing plate is provided above the color filter substrate and below the thin film transistor substrate so that the light transmittance is varied according to the polarization state of the light passing through the liquid crystal layer.

However, it is an important disadvantage that the liquid crystal display device has a narrow viewing angle. In order to overcome these disadvantages, various methods for widening the viewing angle have been developed. Among them, liquid crystal molecules are oriented vertically with respect to the upper and lower substrates, and a method of forming a constant opening pattern or forming protrusions on the pixel electrode and the reference electrode that is the opposite electrode thereof. This is becoming potent.

The method of forming the opening pattern is a method of widening the viewing angle by forming opening patterns on the pixel electrode and the reference electrode, respectively, and adjusting the direction in which the liquid crystal molecules lie down by using a fringe field formed by the opening patterns.

The protrusions are formed by forming protrusions on the pixel electrode and the reference electrode formed on the upper and lower substrates, respectively, to adjust the lying direction of the liquid crystal molecules using an electric field distorted by the protrusions. In order to form such protrusions, a separate process is performed to form.

Accordingly, an object of the present invention is to provide a method capable of forming a protrusion without further processing for forming the protrusion, a thin film transistor substrate and a liquid crystal display device using the same.

The thin film transistor substrate according to the present invention for achieving the above object is a transparent insulating substrate, a gate wiring formed on the insulating substrate, a gate insulating layer formed on the gate wiring, a semiconductor layer formed on the gate insulating layer to form a channel A resistive contact layer formed in the same planar pattern as the semiconductor layer except for a predetermined region of the semiconductor layer, a data line formed on the ohmic contact layer, and a contact hole formed on the data line and exposing a predetermined region of the data line. The branch includes a protective layer, a pixel electrode formed on the protective layer and connected to the data wiring through a contact hole, the pixel electrode including a plurality of small portions, and projections formed between the small portions, and a portion and the projections of the data wiring. The first metal pattern and the third metal pattern to surround the second metal pattern A portion of the data line and portions except protrusions are formed of a double layer of the first metal pattern and the third metal pattern.

The first and second storage electrodes may be formed on the substrate, and may be parallel to the gate wirings, the first storage electrodes connected to the storage electrode lines, and parallel to the data wirings. And a sustain electrode wiring connecting the second and third sustain electrodes and including a fourth sustain electrode parallel to the first sustain electrode.

The pixel electrode may include first to third small portions, and the first small portion and the second small portion may be separated from each other with the second storage electrode interposed therebetween. It is formed so that a sustain electrode may be isolate | separated.

Further, the protrusion is preferably formed on the ohmic contact layer corresponding to the second sustain electrode or the third sustain electrode.

Next, a thin film transistor substrate and a manufacturing method thereof according to an embodiment of the present invention will be described with reference to the drawings.

1A is a layout view of a thin film transistor substrate according to an exemplary embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line Ib-Ib ′ of FIG. 1A.

As shown in the drawing, gate wirings 121 and 123 and sustain electrode wirings 131, 133a, 133b, 133c and 133d are formed on a transparent insulating substrate 110 such as glass. The gate lines 121 and 123 are formed in the gate line 121 that is formed to extend in the horizontal direction, the gate electrode 123 that is a part of the gate line 121, and the gate pad formed at one end of the gate line 121 (not shown). Not).                     

The storage electrode wires 131, 133a, 133b, 133c, and 133d are directly connected to the storage electrode line 131 and the storage electrode line 131 formed in parallel with the gate line 121, and are formed in the vertical direction. Second and third sustain electrodes 133b and 133c connected to the electrode 133a and the first sustain electrode 133a and formed in parallel with the sustain electrode line 131, and the second and third sustain electrodes 133b, And a fourth storage electrode 133d connected to the 133c and formed to be parallel to the first storage electrode 133a. A gate insulating layer 140 is formed on the gate wirings 121 and 123 and the sustain electrode wirings 131, 133a, 133b, 133c, and 133d, and a semiconductor layer made of amorphous silicon is formed on a predetermined region of the gate insulating layer 140. 150, 151, and 154 are formed.

The semiconductor layers 150, 151, and 154 extend in the vertical direction with the channel portion 154 of the thin film transistor positioned on the gate electrode 123, and the data line portion 151 connecting the channel portion 154 up and down. And the protrusions 150 formed in predetermined regions of the sustain electrodes 133a, 133b, 133c, and 133d. Ohmic contact layers 160, 161, 163, and 165 are formed on the semiconductor layers 150, 151, and 154. The ohmic contact layers 160, 161, 163, and 165 are separated from each other on the protrusion contact layer 160 and the channel portion 154 formed under the protrusion, so that the source contact layer 163 and the drain contact layer 165 are provided. Except for forming), it has the same planar pattern as the semiconductor layers 151 and 154. The ohmic contacts 161, 163, and 165 are made of amorphous silicon doped with N-type impurities at a high concentration.

Data lines 171, 173, and 175 are formed on the ohmic contacts 160, 161, 163, and 165. The data lines 171, 173, and 175 intersect the gate line 121 and are formed on the source contact layer 163 as a branch of the data line 171 and the data line 171 which define the pixel area. Data pads facing one of the electrodes 173 and the source electrode 173 and formed at one end of the drain electrode 175 and the data line 171 formed on the drain contact layer 165 (not shown). Not formed). The drain electrode 175 is connected to the pixel electrodes 190a, 190b, 190c, 191a, and 191b, and a part of the drain electrode 175 is connected to the pixel electrodes 190a, 190b, 190c, 191a, and 191b. Extends beyond the contact layer 165.

The protrusions 280a, 280b, and 280c are formed on the protrusions 150. A portion 171 and the projection 280 of the data line are formed in a clad structure. That is, the first metal patterns 171a and 280a and the third metal patterns 171c and 280c surround the second metal patterns 171b and 280b. Except for the portion 171 of the data line, that is, the region of the source electrode 173 and the drain electrode 175 is formed of a double layer of the first metal pattern 173a and the third metal pattern 173c.

A protective layer 180 having a contact hole 181 exposing the drain electrode 175 is formed on the data wires 171, 173, and 175 and the protrusions 280a, 280b, and 280c, and the protective layer 180. The pixel electrodes 190a, 190b, and 190c are connected to the drain electrode 175 through the contact hole 181. The pixel electrodes 190a, 190b, and 190c are made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO).

In this case, the pixel electrodes 190a, 190b and 190c are separated into first to third small portions 190a, 190b and 190c, and the first to third small portions are connected to each other through the connection portions 191a and 191b. It is done. The first small portion 190a is formed in the first region A defined by the storage electrode line 131 and the first, second, and fourth storage electrodes 133a, 133b, and 133d. The first small portion 190a is formed in a rectangular shape with four corners cut out (hereinafter referred to as chamfering). The second small portion 190b is formed in the second region B defined by the first to fourth storage electrodes 133a, 133b, 133c, and 133d in the same form as the first small portion 190a. The second small portion 190b is connected to the first small portion 190a through the first connecting portion 191a.

The third small portion 190c is formed in a rectangular shape chamfered in the third region C defined by the first, third, and fourth sustain electrodes 133a, 133c, and 133d and the gate line 121. The third small portion 190c is connected to the second small portion 190b through the second connecting portion 191b. The first and second small portions 190a and 190b are shorter than the side parallel to the data line 171 than the side parallel to the gate line 121, and the third small part 190c is parallel to the data line 171. The sides are formed longer than the sides parallel to the gate line 121. In addition, the first and second small portions 190a and 190b partially overlap the first and fourth storage electrodes 133a and 133d or the storage electrode line 131, but the third small portion 190c may include the storage electrode wiring ( 131, 133a, 133b, 133c, and 133d. It is common that the potential of the reference electrode of the color filter substrate mentioned later is applied to the sustain electrode wirings 131, 133a, 133b, 133c, and 133d.

A method of forming such a thin film transistor substrate will be described with reference to the accompanying drawings. 2A to 5A are layout views sequentially illustrating a method of forming a thin film transistor substrate according to the present invention, and FIGS. 2B to 5B are cross-sectional views taken along cut lines of FIGS. 2A to 5A, respectively.

First, as shown in FIGS. 2A to 2B, a metal layer is formed on the transparent insulating substrate 110 and then patterned to form gate wirings 121 and 125 and sustain electrode wirings 131, 133a, 133b, 133c, and 133d. do. The gate insulating layer 140 is formed of an insulating material such as silicon nitride.

As shown in FIGS. 3A to 3B, an amorphous silicon layer without an impurity doped and an amorphous silicon layer doped with an impurity are formed on the gate insulating layer 140 and then patterned at the same time to form the semiconductor layers 151 and 154. Contact layers 160, 160A, 161 are formed. The ohmic contact layers 160, 160A, and 161 are connected to the channel portion 160A.

As shown in FIGS. 4A to 4B, after depositing the first metal layer 701 and the second metal layer 702 on the ohmic contacts 160A and 161, the second metal layer 702 is patterned to form a second metal pattern. 171b and 280b are formed. The third metal layer 703 is formed on the second metal patterns 171b and 280b.

As shown in FIGS. 5A to 5B, the third metal layer 703 and the first metal layer 701 are simultaneously patterned to form a source including the first metal patterns 173a and 175a and the third metal patterns 173c and 175c. Data lines 171a, 171b, 171c and protrusions 280a, 280b, and 280c including the electrode 173, the drain electrode 175, and the first to third metal patterns 171a, 171b, 171c, 280a, 280b, and 280c. ). The first and third metal layers 701 and 703 are formed of chromium, and the second metal layer uses aluminum or silver having low resistance.

The protrusions 280a, 280b, and 280c are formed in predetermined regions corresponding to the sustain electrode wirings 131, 133a, 133b, 133c, and 133d. That is, it is formed in a region corresponding to the second and third sustain electrodes 133b and 133c.

The channel portion 160A of the ohmic contact layer is etched using the data wiring as a mask to separate the source contact layer 163 and the drain contact layer 165 to complete the ohmic contact layers 160, 161, 163, and 165. .

6A to 6B, a protective layer having a first contact hole 181 exposing the drain electrode 175 on the data lines 171, 173, and 175 and the protrusions 280a, 280b, and 280c. 180).

Thereafter, a transparent conductive layer is formed on the passivation layer, and then patterned to form the pixel electrode 190 having the first to third small portions 190a, 190b, and 190c and the connecting portions 191a and 191b connecting them. 1A through 1B) the pixel electrode 190 is connected to the drain electrode 175 through the first contact hole 181.

The liquid crystal display device including the thin film transistor substrate described above will be described. FIG. 7A is a layout view of a color filter substrate included in the liquid crystal display according to the present invention, FIG. 7B is a cross-sectional view taken along line VIIb-VIIb ′ of FIG. 7A, and FIG. 8 is a layout view of the liquid crystal display according to the present invention.

First, as illustrated in FIGS. 7A and 7B, the black matrix 220 formed of a chromium / chromium oxide bilayer on a transparent substrate 210 made of glass or the like defines a pixel region. The pixel region corresponds to the pixel region of the thin film transistor substrate. The color filter 230 is formed in each pixel area. In the color filter 230, red, blue, and green color filters are alternately formed, and the same color filter is formed in one direction. 7 illustrates a color filter formed in one pixel area.

The reference electrode 270 made of a transparent conductor is formed on the entire surface of the substrate 210 on the color filter 230. At this time, the reference electrode 270 has first to third openings 271, 272, and 273. The first opening 271 divides the lower half of the pixel region from side to side, and the second opening 272 and the third opening 273 divide the upper half of the pixel region into three portions. Both ends of each of the openings 271, 272, and 273 gradually expand to form an isosceles triangle. The black matrix 220 may be formed of an organic material, and the color filter 230 may be formed on the thin film transistor substrate.

Next, a liquid crystal display including the color filter substrate and the thin film transistor substrate described above will be described with reference to FIG. 8. First, the thin film transistor substrate illustrated in FIG. 2A and the color filter substrate illustrated in FIG. 7A are aligned and combined, and a liquid crystal material is injected between the two substrates to align them vertically. Here, the two polarizing plates are disposed outside the two substrates such that their polarization axes are perpendicular to each other to form a liquid crystal display.

When the two substrates are aligned, the small portions 190a, 190b, and 190c of the pixel electrode of the thin film transistor substrate and the openings 271, 272, and 273 formed in the reference electrode 270 of the color filter substrate overlap with each other. Split into multiple domains. Therefore, a fringe field is formed between the protrusions 280a, 280b, and 280c between the protrusions and the reference electrode so that the liquid crystal is inclined constantly.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements using the basic concept of the present invention as defined in the following claims are also within the scope of the present invention. It belongs to.

As described above, when the data wiring of the clad structure is formed, the processes for forming the protrusions can be omitted by simultaneously forming the protrusions for determining the orientation of the liquid crystal, thereby reducing the overall process. In addition, the formation of a texture can be suppressed by applying a voltage such as a reference electrode to the protrusion.

Claims (6)

Insulation board, A gate wiring and a data wiring formed on the insulating substrate and crossing each other; A thin film transistor connected to the gate line and the data line, A pixel electrode connected to the thin film transistor and including a plurality of small portions; and Projections formed between the small portions Including, The protrusion is formed such that the first metal pattern and the third metal pattern surround the second metal pattern, And the data line and the thin film transistor have a first portion having the same stacked structure as the protrusions and a second portion formed of a double layer of the first metal pattern and the third metal pattern. In claim 1, Is formed on the substrate, A storage electrode line parallel to the gate wiring, A first sustain electrode connected to the sustain electrode line and parallel to the data line; Second and third sustain electrodes connected to the first sustain electrodes and parallel to the gate lines; And a sustain electrode wiring connecting the second and third sustain electrodes and including a fourth sustain electrode parallel to the first sustain electrode. In claim 2, The pixel electrode is composed of first to third small portions, The first small portion and the second small portion are formed to be separated with the second storage electrode therebetween, and the second small portion and the third small portion are formed to be separated with the third storage electrode therebetween. Thin film transistor substrate. In claim 2, And a resistive contact layer corresponding to the second sustain electrode or the third sustain electrode, And the protrusions are formed on the ohmic contact layer. In claim 1, The thin film transistor includes a source electrode and a drain electrode, and the data line includes a data line connected to the source electrode of the thin film transistor. The first portion is the data line, And the second portion is the source electrode and the drain electrode. In claim 4, And the ohmic contact layer has the same planar pattern as the data line.

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