KR100333982B1 - Thin film transistor substrate for liquid crystal display - Google Patents

Abstract

In a thin film transistor substrate for a liquid crystal display device, a gate line and a common electrode line are formed in a horizontal direction on an insulating substrate, a gate insulating film is formed thereon, and a semiconductor pattern is formed on the gate insulating film. A data line is formed in the vertical direction on the gate insulating film, a source electrode, a drain electrode, and a pixel electrode are formed, and a protective film having a contact hole for exposing the data line is formed on the data line and the pixel electrode. A redundant data line is formed on the passivation layer to be connected to the data line through a contact hole. The redundant data line is formed so as not to overlap the data line at a portion crossing the gate line and the common electrode line. When the thin film transistor substrate is manufactured in such a structure, when the data line is shorted with the gate line or the common electrode line, both shorted portions of the data line can be repaired by using a laser.

Description

Thin film transistor substrate for liquid crystal display

The present invention relates to a thin film transistor substrate for a liquid crystal display device.

In general, a liquid crystal display device injects a liquid crystal material between an upper substrate on which a common electrode, a color filter, and the like are formed, and a lower substrate on which a thin film transistor and a pixel electrode are formed. By applying a different potential to form an electric field to change the arrangement of the liquid crystal molecules, and through this to control the light transmittance is a device that represents the image. Here, the lower substrate of the liquid crystal display device in which the thin film transistor is formed is also called a thin film transistor substrate, and the structure thereof is as follows.

The gate line extends in the horizontal direction on the insulating substrate, the common electrode line is formed in parallel with the gate line, and the common electrode is formed in the form of branch lines on the common electrode line. A gate insulating film is formed on the gate line and the common electrode, and a semiconductor pattern is formed on the gate insulating film on the portion corresponding to the gate electrode of the gate line, and a contact layer is formed on both sides of the semiconductor pattern on the gate pattern. Is formed. Further, a data line extending in the vertical direction is formed on the gate insulating film, and a source electrode extending up to one contact layer is formed in the form of a branch, and a drain electrode is formed on the other contact layer. The drain electrode is connected to the pixel electrode. In this case, the pixel electrode may be formed in the same layer as the drain electrode, or may be connected to the drain electrode through a contact hole formed in the protective film while being formed on the protective film covering the drain electrode and the data line. Also, a contact hole for exposing the data line is formed in the passivation layer, and a redundant data line connected to the data line is formed on the passivation layer so as to overlap the data line on the passivation layer to prepare for disconnection of the data line. Alternatively, a repair line may be formed around the active region where the gate line and the data line intersect to prepare for disconnection of the wiring.

However, there is a case where a short circuit occurs at a portion where the gate line and the data line cross each other. In this case, a repair method using a repair line is inevitably used. In other words, it can only be repaired by connecting both ends of the shorted data line with a repair line and cutting both shorted parts of the data line with a laser, and using a redundant data line formed by overlapping the data line, a short circuit between the gate line and the data line It cannot be repaired. This is because redundant data lines are also cut together when cutting both shorted portions of the data lines with a laser. However, as a liquid crystal display device is enlarged, a method of using a repair line becomes difficult due to a serious problem caused by a delay capacitance (RC) delay.

An object of the present invention is to easily repair a short circuit between wirings in a thin film transistor substrate for a liquid crystal display device.

1 is a layout view of a thin film transistor substrate for a liquid crystal display according to a first exemplary embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line II-II ′ of FIG. 1;

3 is a layout view of a thin film transistor substrate for a liquid crystal display according to a second exemplary embodiment of the present invention.

4 is a cross-sectional view taken along line III-III ′ of FIG. 3.

In order to solve this problem, in the present invention, the redundant data line is formed so as not to overlap the data line at the portion where the redundant data line intersects the gate line or the common electrode line.

Specifically, the gate line and the common electrode line are formed side by side on the insulating substrate, an insulating film is formed on the gate line and the common electrode line, and the first semiconductor layer is formed on the insulating film so as to overlap with the gate line. A contact layer is formed on both sides of the first semiconductor layer around the gate electrode, and a source electrode and a drain electrode are formed on the contact layer, and a data line is connected to the source electrode and the gate line and the common electrode. It is formed to intersect with the electrode line. A pixel electrode is formed on the insulating film so as to be connected to the drain electrode, and a protective film having a contact hole for exposing the data line is formed on the data line and the pixel electrode, and the redundancy connected to the data line through the contact hole on the protective film. The data line is formed so as not to intersect the data line at the portion where the gate line and the data line intersect.

In this case, the redundant data line may be formed so as not to overlap the data line even at the intersection of the common electrode line and the data line, the intersection of the gate line and the data line, the intersection of the common electrode line and the data line, the gate line and the redundant data. The semiconductor device may further include a second semiconductor layer formed on the insulating layer under the portion where the lines cross and the portion where the common electrode line and the redundant data line cross.

Alternatively, the redundant data line segments having the gate line and the common electrode line formed side by side on the insulating substrate and formed perpendicular to the gate line and bent at both ends are formed on the insulating substrate so as not to cross the gate line or the common electrode line. An insulating film having a first contact hole for exposing the redundant data line segment is formed on the line, the common electrode line, and the redundant data line segment, and a semiconductor layer is formed on the insulating layer so that a portion of the semiconductor layer overlaps with the gate line. A contact layer is formed on both sides of the semiconductor layer, with the gate electrode separated from each other. A source electrode and a drain electrode are formed on the contact layer, and a data line intersecting the gate line and the common electrode line is connected to the source electrode. It is connected and formed so that the redundant data line segment and a part may overlap. The passivation layer covering the data line is formed to have a second contact hole exposing the first contact hole and a third contact hole exposing the drain electrode, and the pixel electrode connected to the drain electrode through the third contact hole is a protective film. It is formed above, and the connecting piece which contacts the redundant data line segment via the 1st and 2nd contact hole and connects the adjacent redundant data line segment is formed on the protective film.

In this case, a fourth contact hole for exposing a data line disposed between the gate line and the common electrode line is formed in the passivation layer, and the connection piece may have a branch connected to the data line through the fourth contact hole.

Next, a thin film transistor substrate for a liquid crystal display according to an exemplary embodiment of the present invention will be described with reference to the drawings.

1 is a layout view of a thin film transistor substrate for a liquid crystal display according to a first exemplary embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line II-II ′ of FIG. 1.

The gate line 20 is formed in the horizontal direction on the transparent insulating substrate 10 such as glass, and the common electrode line 30 is formed in parallel with the gate line 20. Here, two common electrode lines 30 are formed between two adjacent gate lines 20, and the common electrodes 31 connecting the two common electrode lines 30 are formed at regular intervals.

A gate insulating film 40 is formed on the gate line 20 and the common electrode line 30, and a first semiconductor pattern made of amorphous silicon or the like is formed on the gate insulating film 40 on the gate electrode which is a part of the gate line 20. 50 is formed and the second semiconductor pattern 51, which is separated from the first semiconductor pattern 50, intersects the gate line 20 and the common electrode line 30 positioned on both sides of the gate line 20. It is formed to. In this case, the second semiconductor pattern 51 is to prevent the gate line 20, the common electrode line 30, and the data line 70, which will be described later, from being short-circuited, and is sometimes connected to the first semiconductor pattern. It may be.

First and second contacts on the first semiconductor pattern 50 which are separated on both sides of the gate electrode 21, which is part of the gate line 20, and are made of amorphous silicon doped with N-type impurities at high concentration. Layers 61 and 62 are formed, and a third contact layer 60 is also formed on the second semiconductor pattern 51. Since the contact layers 60, 61, and 62 are formed by using the data line 70, the source electrode 71, the drain electrode 72, and the like, which will be described later, as an etch mask, they have the same pattern as the data line 70 and the like.

The data line 70 is formed in the vertical direction on the third contact layer 60, and the source electrode 71 is formed as a branch of the data line 70 and extends over the first contact layer 61. The drain electrode 72 is formed on the second contact layer 62. The pixel electrode 73 is connected to the drain electrode 72 on the gate insulating layer 40 in a pixel region defined as an area formed by crossing two neighboring gate lines 20 and two neighboring data lines 70. Is formed. In this case, the pixel electrode 73 includes a main bar overlapping the two upper and lower common electrode lines 30 and branch lines connecting the main bars. Here, the branch lines of the pixel electrode 73 are alternately arranged with the common electrode 31 of the common electrode line 30.

A passivation film 80 having a contact hole 91 exposing the data line 70 is formed on the data line 70 and the pixel electrode 73. The contact hole 91 is formed on the passivation film 80. A redundant data line 90 is formed to be connected to the data line 70. In this case, the redundant data line 90 is made of chromium (Cr) or the like, and overlaps the data line 70 but is formed so as not to overlap at a portion crossing the common electrode line 30 and the gate line 20. . This is a redundant data line 90 when a laser is used to cut both ends of the shorted portion of the data line 70 to repair the gate line 20 or the common electrode line 30 and the data line 70 shorted. ) Is to avoid cutting. Here, the redundant data line 90 may be formed so as not to overlap the data line 70 only at a portion crossing the gate line 20. In this case, only the short circuit with the gate line 20 is considered. Here, since the redundant data line 90 is formed on the passivation layer 80, there is little concern that the redundant data line 90 may be shorted with the gate line 20 or the common electrode line 30.

Next, a method of repairing the gate line 20, the common electrode line 30, and the data line 70 in a short circuit in the thin film transistor substrate having such a structure will be described.

First, when a short circuit A occurs at a portion where the gate line 20 and the data line 70 intersect, the C and D portions of the data line 70 may be cut by using a laser. At this time, since the data line 70 signal is transmitted through the redundant data line 90, there is no problem in driving the liquid crystal display. Next, when a short circuit B occurs at a portion where the common electrode line 30 and the data line 70 intersect, cutting the F and G portions of the data line 70 or cutting the F and E portions using a laser. do. At this time, when cutting the F and E portions, since the source electrode 71 formed therebetween is separated from the data line 70, the pixel electrode 73 receiving the signal from the source electrode 71 is separated. The function will be lost. Therefore, it is better to cut the F and G parts if possible. Even when the data line 70 is short-circuited with both the common electrode line 30 and the gate line 20, a position where the function of the pixel electrode can be utilized can be selected as much as possible, and both ends of the short-circuited portion may be cut.

A thin film transistor substrate for a liquid crystal display device according to a second embodiment of the present invention will be described.

3 is a layout view of a thin film transistor substrate for a liquid crystal display according to a second exemplary embodiment of the present invention, and FIG. 4 is a cross-sectional view taken along line III-III ′ of FIG. 3.

The gate line 200 is formed in the horizontal direction on the transparent insulating substrate 100, and the common electrode line 300 is formed in parallel with the gate line 200. The common electrode branch line 310 is connected to the common electrode line 300 to form a storage capacitor between the pixel electrode 110 to be described later. A redundant data line segment 900 is formed in the vertical direction between the common electrode line 300 and the gate line 200. Here, both ends of the redundant data line interceptor 900 are bent.

The gate insulating layer 400 is formed on the gate line 200, the common electrode line 300, and the redundant data line slice 900. In this case, a contact hole 113 is formed in the gate insulating layer 400 to expose both ends of the redundant data line segment 900. On the gate insulating layer 400, a semiconductor pattern 500 made of amorphous silicon or the like is formed over an upper portion of the gate electrode 210, a portion of the gate line 200, and an upper portion of the gate line 200 and the common electrode line 300. It is. First and second contact layers 610 and 620, which are separated on both sides of the gate electrode 210 and heavily doped with N-type impurities, are formed on the semiconductor pattern 500. The data line 700 is formed in the vertical direction on the gate insulating layer 400, and the source electrode 710 is formed on the first contact layer 610 as a branch of the data line 700. The drain electrode 720 is formed on the second contact layer 620.

The first contact 111 exposing the drain electrode 720 and the second contact 112 exposing the source electrode 710 are disposed on the data line 700, the source electrode 710, the drain electrode 720, and the like. ) And a third contact hole 113 exposing both ends of the redundant data line segment. A pixel electrode 110 connected to the drain electrode 720 through the first contact hole 111 and partially overlapping the common electrode line 300 and the common electrode branch line 310 is formed on the passivation layer 800. The redundant data line connecting piece 120 is connected to the source electrode 710 through the second contact hole 112 and connects the redundant data line segment 900 through the third contact hole 113. . Here, the redundant data line connecting piece 120 may be formed of the same material as that of the pixel electrode 110, that is, an indium tin oxide (ITO) or the like, except for the branch portion for connecting to the source electrode 710. It is formed so as not to overlap with the data line 700. The redundant data line connecting piece 120 is connected to the source electrode 710 to connect the redundant data line 900 and 120 to the data line 700.

Next, a method of repairing the gate line 200, the common electrode line 300, and the data line 700 in a short circuit in the thin film transistor substrate having such a structure will be described.

First, when a short circuit A 'occurs at a portion where the gate line 200 and the data line 700 cross each other, a portion D' and E 'of the data line 700 and a G' of the redundant data line connecting piece 120 are included. The part may be cut using a laser. When a short circuit B 'occurs at a portion where the common electrode line 300 and the data line 700 intersect, the portions D' and C 'of the data line 700 may be cut by using a laser.

By forming the redundant data line as described above, it can be easily repaired when the data line is shorted with the gate line or the common electrode line.

Claims (6)

Insulated substrate (correction), A gate line formed on the insulating substrate and having a gate electrode, A common electrode line formed on the insulating substrate and electrically separated from the gate line; An insulating film formed on the gate line and the common electrode line, A first semiconductor layer formed on the insulating layer and partially overlapping the gate line; A contact layer formed on the first semiconductor layer and separated on both sides of the gate electrode; A source electrode formed on one side of the contact layer, A drain electrode formed on the other side of the contact layer, A data line formed on the insulating layer and crossing the gate line and the common electrode line and connected to the source electrode; A pixel electrode formed on the insulating layer and connected to the drain electrode; A protective film formed on the data line and having a contact hole for exposing the data line, A redundant data line formed on the passivation layer and connected to the data line through the contact hole and formed so as not to overlap the data line at a portion where the gate line and the data line cross each other; Thin film transistor substrate for a liquid crystal display device comprising a. In claim 1, And the redundant data line is formed so as not to overlap the data line even at a portion where the common electrode line and the data line cross each other. The method of claim 1 or 2, A portion where the gate line and the data line intersect, a portion where the common electrode line and the data line intersect, a portion where the gate line and the redundant data line intersect, and a portion under the portion where the common electrode line and the redundant data line intersect. A thin film transistor substrate for liquid crystal display device further comprising a second semiconductor layer formed over the insulating film. Insulation board, A gate line formed on the insulating substrate, A redundant data line segment formed on the insulating substrate so as not to cross the gate line; An insulating film formed over said gate line and said redundant data line segment and having a first contact hole for exposing said redundant data line segment; A semiconductor layer formed on the insulating layer and partially overlapping the gate line; A contact layer formed on the semiconductor layer and separated on both sides of the gate line; A source electrode formed on one side of the contact layer, A drain electrode formed on the other side of the contact layer, A data line formed on the insulating film, crossing the gate line, connected to the source electrode, and partially overlapping the redundant data line segment; A passivation layer covering the data line and having a second contact hole exposing the first contact hole and a third contact hole exposing the drain electrode; A pixel electrode formed on the passivation layer and connected to the drain electrode through the third contact hole; Formed on the passivation layer and connected to the redundant data line segment through the first and second contact holes, and adjacent to the redundant data line segment, and at least in a portion where the data line and the gate line intersect the data. Connections Do Not Overlap Lines Thin film transistor substrate for a liquid crystal display device comprising a. In claim 4, And a fourth contact hole exposing the data line, wherein the connection piece has a branch connected to the data line through the fourth contact hole. The method of claim 4 or 5, And a common electrode line formed on the substrate and having a common electrode partially overlapping the pixel electrode.