KR100752207B1 - Liquid Crystal Display Device - Google Patents

Abstract

The present invention provides a liquid crystal display capable of repairing a point defect caused by a short circuit between a gate line and a data line or an electrical short circuit between a gate line and a dummy electrode used as an upper electrode of a capacitor. Relates to a device.

A liquid crystal display device according to the present invention comprises a transparent substrate; A ladder-shaped gate line having a connecting portion connecting the first and second wirings arranged side by side on the transparent substrate and the first and second wirings; A gate electrode connected to the gate line; A gate insulating layer formed on the transparent substrate to cover the gate electrode and the gate line; A data line formed on the gate insulating layer to intersect the gate line and overlapping only the first and second wires of the gate line; A source electrode connected to the data line; A drain electrode formed to correspond to the source electrode with the gate electrode interposed therebetween; A passivation layer formed to cover the data line, the drain electrode, and the source electrode; A pixel electrode formed in an area provided at the intersection of the gate line and the data line and electrically connected to the drain electrode through a first contact hole formed to expose the drain electrode in the passivation layer; And a dummy electrode formed at the same time as the data line and overlapping only the first and second wires of the gate line and electrically connected to the pixel electrode through a second contact hole.

Therefore, when the gate line is shorted with the data line or the dummy electrode, any one of the first and second wires of the gate line is cut by the laser beam and repaired, thereby preventing point defects.

Description

Liquid Crystal Display Device             

1 is a plan view of a liquid crystal display according to the related art.

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

<Explanation of symbols for main parts of the drawings>

21: transparent substrate 23: gate line

25 gate electrode 27 data line

29 drain electrode 31 source electrode

32 dummy electrode 33 pixel electrode

35, 37: first and second contact holes

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display (LCD). In particular, a short circuit between a gate line and a data line or an electrical short circuit between a gate line and a dummy electrode used as an upper electrode is used as a lower electrode of a capacitor. The present invention relates to a liquid crystal display device capable of repairing point defects generated.

In the liquid crystal display device, a pixel based on a pixel electrode for controlling a liquid crystal that transmits or reflects light incident and injected between a switching element, which is a driving element formed of a thin film transistor, and a substrate, is vertically and horizontally. It has an arranged structure.

In a liquid crystal display device, a unit pixel consisting of a thin film transistor, which is a switching element, and a pixel electrode connected thereto, is vertically and horizontally arranged in a matrix state of N × M (where N and M are natural numbers) on a lower substrate, respectively. N gate lines and M data lines that transmit signals to transistor gate electrodes and source electrodes are formed to cross the gate lines.

In addition, the liquid crystal display device has a storage capacitor for improving the retention characteristics of the liquid crystal applied voltage, stabilization of gray scale display, and prevention of afterimage.

The storage capacitor uses an electrode formed at the same time as the gate line or the gate line as the lower electrode, and an electrode formed at the same time as the data line as the upper electrode and connected to the pixel electrode through the contact hole. In addition, the accumulation capacitor uses a gate insulating film as the dielectric layer.

1 is a plan view of a liquid crystal display according to the prior art.

The liquid crystal display according to the prior art includes a thin film transistor and a storage capacitor. In the liquid crystal display, N gate lines 3 and M data lines 7 are formed on the transparent substrate 1 to define N × M pixel regions. In the above, the gate line 3 and the data line 7 are formed of metal, and a gate insulating layer (not shown) is formed therebetween to electrically insulate. N × M pixels are formed in the N × M pixel regions, which are driven by a thin film transistor, which is a switching element formed to be electrically connected to the gate line 3 and the data line 7. do.

The thin film transistor is formed of a gate electrode 5, a drain and source electrodes 9 and 11, a semiconductor layer (not shown) and an ohmic contact layer (not shown). In the above, the gate electrode 5 is formed to be connected to the gate line 3, and the source electrode 11 is connected to the data line 7. The drain electrode 9 is formed to correspond to the source electrode 11 with the gate electrode 5 interposed therebetween.

A passivation layer (not shown) is formed to cover the thin film transistor having the above-described structure. The passivation layer is formed of an inorganic insulating material such as silicon nitride or an organic insulating material such as acryl-based organic compound, BCB (benzocyclobutene) or PFCB (perfluorocyclobutane).

The pixel electrode 13 is formed in the pixel region on the passivation layer. The pixel electrode 13 is formed of a transparent conductive material such as indium tin oxide (ITO), tin oxide (TO), or indium zinc oxide (IZO), and is formed of a first contact hole. 15 is connected to the drain electrode 9. The pixel electrode 13 may be formed such that a predetermined portion of the pixel electrode 13 overlaps the data line 7 to increase the aperture ratio.

The accumulation capacitor uses an adjacent gate line 3 as a lower electrode, and uses a separate dummy electrode 12 formed as an upper electrode when the data line 7 is formed to overlap the gate line 3. In addition, the dummy electrode 12 is electrically connected to the pixel electrode 13 through the second contact hole 17.

However, the liquid crystal display of the above-described configuration has a problem in that a gate defect is short-circuited due to a dummy electrode, a data line, and a metallic foreign material.

Accordingly, an object of the present invention is to provide a liquid crystal display device capable of repairing a point defect caused by a short circuit between a gate line used as a lower electrode of a capacitor and a dummy electrode and data line used as an upper electrode. To provide.

A liquid crystal display device according to the present invention for achieving the above object is a transparent substrate; A ladder-shaped gate line having a connecting portion connecting the first and second wirings arranged side by side on the transparent substrate and the first and second wirings; A gate electrode connected to the gate line; A gate insulating layer formed on the transparent substrate to cover the gate electrode and the gate line; A data line formed on the gate insulating layer to intersect the gate line and overlapping only the first and second wires of the gate line; A source electrode connected to the data line; A drain electrode formed to correspond to the source electrode with the gate electrode interposed therebetween; A passivation layer formed to cover the data line, the drain electrode, and the source electrode; A pixel electrode formed in an area provided at the intersection of the gate line and the data line and electrically connected to the drain electrode through a first contact hole formed to expose the drain electrode in the passivation layer; And a dummy electrode formed at the same time as the data line and overlapping only the first and second wires of the gate line and electrically connected to the pixel electrode through a second contact hole.

Other objects and features of the present invention in addition to the above object will become apparent from the description of the embodiments with reference to the accompanying drawings.

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

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

The liquid crystal display according to the present invention includes a thin film transistor and a storage capacitor. In the liquid crystal display device, N gate lines 23 and M data lines 27 cross each other on the transparent substrate 21 to define N × M pixel regions. The gate line 23 and the data line 27 are formed of a conductive metal, and a gate insulating layer (not shown) made of an insulating material such as silicon nitride or silicon oxide is formed between the gate line 23 and the data line 27 to electrically insulate the gate line 23 and the data line 27. The gate line 23 is also used as a lower electrode of the accumulation capacitor and is formed in a ladder shape. That is, the gate line 23 may be formed to intersect the first line 23a formed to cross the data line 27, the second line 23b spaced apart from the first line 23a at regular intervals, and the first line 23b. A plurality of connecting portions 23c for connecting the wiring 23a and the second wiring 23b are included. In this case, the connecting portion 23c may include a portion where the dummy electrode 32 used as the upper electrode of the capacitor overlaps the first and second wirings 23a and 23b, and the data line 27 may include the first and second wirings ( It is formed in the area | region except the part which overlaps with 23a) and 23b.

N × M pixels are formed in the N × M pixel regions, which are driven by thin film transistors, which are switching elements formed to be electrically connected to the gate lines 23 and the data lines 27. .

The thin film transistor is formed of a gate electrode 25, a drain and source electrodes 29 and 31, a semiconductor layer (not shown) and an ohmic contact layer (not shown). The gate electrode 25 is formed to be connected to the gate line 23, and the source electrode 31 is connected to the data line 27. The drain electrode 29 is formed to correspond to the source electrode 31 with the gate electrode 25 therebetween. The semiconductor layer (not shown) between the drain electrode 29 and the source electrode 31 becomes a channel.

A passivation layer (not shown) covering the thin film transistor is formed on the above-described structure. The passivation layer is formed of an inorganic insulating material such as silicon nitride or an organic insulating material such as acryl-based organic compound, BCB (benzocyclobutene) or PFCB (perfluorocyclobutane).

The pixel electrode 33 is formed in the pixel region on the passivation layer. The pixel electrode 33 is formed of a transparent conductive material such as indium tin oxide (ITO), tin oxide (TO), or indium zinc oxide (IZO), and is formed of a first contact hole. It is connected to the drain electrode 29 through 35. The pixel electrode 33 may be formed such that a predetermined portion of the pixel electrode 33 overlaps with the data line 27 to increase the aperture ratio.

The accumulation capacitor uses an adjacent gate line 23 as a lower electrode, and uses a separate dummy electrode 32 formed to overlap the gate line 23 as an upper electrode when the data line 27 is formed. As described above, the dummy electrode 32 overlaps only the first and second wires 23a and 23b of the gate line 23 and is not overlapped with the connection portion 23c. In addition, the dummy electrode 32 is electrically connected to the pixel electrode 33 through the second contact hole 37.

In the above-described liquid crystal display device, when the gate line 23 is shorted due to the dummy electrode 32 or the data line 27 and metallic foreign material, a point defect is generated, the gate line 23 is used. One of the first and second wirings 23a and 23b is cut into a laser beam and repaired. That is, when the data line 27 or the dummy electrode 32 is shorted with one of the first and second wirings 23a and 23b of the gate line 23, the data line 27 or the dummy electrode of the shorted wiring Both sides of the portion overlapping with 32 are cut by a laser beam. Therefore, the part short-circuited with the data line 27 or the dummy electrode 32 among the first and second wirings 23a and 23b is 'open' electrically with the gate line 23 so that the point defect is repaired. (repair)

In addition, according to the present invention, even if the pixel electrode 33 and the gate line 23 are short-circuited as well as the data line 27 or the dummy electrode 32, the above-described method can be repaired.

As described above, the liquid crystal display according to the present invention includes a gate line, which is also used as a lower electrode of the storage capacitor, having a ladder shape, that is, a connection part connecting the first and second wires parallel to the first and second wires. The data line and the dummy electrode overlap only the first and second wiring portions of the gate line, and do not overlap the connection portion. Therefore, when the gate line is shorted by a data line or a dummy electrode and metallic foreign material, and a point defect occurs, one of the first and second wires of the gate line is cut by a laser beam. .

Accordingly, when the gate line is shorted with the data line or the dummy electrode, the liquid crystal display according to the present invention cuts and repairs any one of the first and second wires of the gate line with a laser beam, thereby preventing point defects. There is an advantage to that.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (2)

A transparent substrate; A ladder-shaped gate line having a connecting portion connecting the first and second wirings arranged side by side on the transparent substrate and the first and second wirings; A gate electrode connected to the gate line; A gate insulating layer formed on the transparent substrate to cover the gate electrode and the gate line; A data line formed on the gate insulating layer to intersect the gate line and overlapping only the first and second wires of the gate line; A source electrode connected to the data line; A drain electrode formed to correspond to the source electrode with the gate electrode interposed therebetween; A passivation layer formed to cover the data line, the drain electrode, and the source electrode; A pixel electrode formed in an area provided at the intersection of the gate line and the data line and electrically connected to the drain electrode through a first contact hole formed to expose the drain electrode in the passivation layer; And a dummy electrode formed at the same time as the data line and overlapping only the first and second wirings of the gate line and electrically connected to the pixel electrode through a second contact hole. The method of claim 1, The connecting portion, And a portion where the dummy electrode overlaps the first and second lines and a portion where the data line crosses the first and second lines.

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