KR100469505B1 - Liquid crystal display device and method for reparing thereof - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device. In particular, in order to repair short circuits between data lines occurring in the data pad link unit, a repair line is formed in advance in the data pad link unit with a gate material, and at the both ends of the repair line when a data line short circuit occurs. After cutting the adjacent data line using a laser, welding the data line of the part overlapping with both ends of the repair line with the gate insulating film therebetween using the laser to electrically connect the repair line and the data line to each other Repair the paragraph.

Description

Liquid crystal display and its repair method {LIQUID CRYSTAL DISPLAY DEVICE AND METHOD FOR REPARING THEREOF}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device and a repair method capable of repairing short circuits between data lines mainly occurring in the data pad link unit.

In general, a liquid crystal display device displays a desired image by individually supplying data signals according to image information to liquid crystal cells arranged in a matrix form, and adjusting a light transmittance of the liquid crystal cells. to be.

Accordingly, a liquid crystal display device includes: a liquid crystal panel in which liquid crystal cells in pixel units are arranged in a matrix form; A driver integrated circuit (IC) for driving the liquid crystal cells is provided.

The liquid crystal panel includes a color filter substrate and a thin film transistor array substrate facing each other, and a liquid crystal layer filled between the color filter substrate and the thin film transistor array substrate.

Further, data lines for transmitting a data signal supplied from a data driver integrated circuit to the liquid crystal cells on the thin film transistor array substrate of the liquid crystal panel, and gate lines for transmitting a scan signal supplied from the gate driver integrated circuit to the liquid crystal cells. Are orthogonal to each other, and liquid crystal cells are defined at each intersection of these data lines and the gate lines. One end of the data lines and the gate lines may include a data pad and a gate pad to which a data signal and a scan signal are applied from the data driver integrated circuit and the gate driver integrated circuit.

The gate driver integrated circuit sequentially supplies scanning signals to the gate lines so that the liquid crystal cells arranged in a matrix form are sequentially selected one by one, and the selected one line of liquid crystal cells is selected from the data driver integrated circuit. The data signal is supplied.

Meanwhile, a common electrode and a pixel electrode are formed on inner surfaces of the color filter substrate and the thin film transistor array substrate facing each other to apply an electric field to the liquid crystal layer. In this case, the pixel electrode is formed for each liquid crystal cell on the thin film transistor array substrate, while the common electrode is integrally formed on the entire surface of the color filter substrate. Therefore, by controlling the voltage applied to the pixel electrode in a state where a voltage is applied to the common electrode, it is possible to individually control the light transmittance of the liquid crystal cells.

Each liquid crystal cell is also provided with a thin film transistor used as a switching element. In the liquid crystal cells in which the scan signal is supplied to the gate electrode of the thin film transistor through the gate lines, a conductive channel is formed between the source electrode and the drain electrode of the thin film transistor, wherein the conductive line is supplied to the source electrode of the thin film transistor through the data lines. As the data signal is supplied to the pixel electrode via the drain electrode of the thin film transistor, an electric field is applied to the liquid crystal layer of the liquid crystal cell.

In the thin film transistor array substrate and the color filter substrate constituting the liquid crystal panel, a plurality of unit panels are formed on a large glass substrate, and in general, four or six units are formed at the same time, and each unit panel is cut to improve yield. have. A manufacturing process of such a liquid crystal display will be briefly described as follows.

First, unit pixels including a thin film transistor, a pixel electrode, and a storage capacitor are formed in a matrix form on a thin film transistor array substrate, and a black matrix, R, G, B color filters, and a common electrode are sequentially formed on a color filter substrate. do.

Next, an alignment layer is formed on the thin film transistor array substrate and the color filter substrate, and then rubbing is performed. At this time, rubbing is a process of rubbing the cloth with the surface of the alignment film at a uniform pressure and speed, by rubbing, the polymer chains on the surface of the alignment film are aligned in a predetermined direction to determine the initial alignment direction of the liquid crystal.

Then, a seal pattern is printed on the color filter substrate, and a spacer is spread on the thin film transistor array substrate. At this time, the seal pattern printing and the spacer spread may be carried out in reverse to the above depending on the process conditions, or may be carried out simultaneously on any one substrate. The seal pattern provides a gap for injecting the liquid crystal together with the spacer and prevents leakage of the injected liquid crystal.

Then, the thin film transistor array substrate and the color filter substrate are bonded together.

Next, the bonded thin film transistor array substrate and the color filter substrate are cut into unit panels. In this case, the liquid crystal display device forms a plurality of thin film transistor array substrates on a large mother substrate, forms a plurality of color filter substrates on a separate mother substrate, and then joins the two mother substrates to simultaneously connect the plurality of liquid crystal panels. Since it forms and aims at improving a yield, it cuts into a unit panel.

In general, the cutting of the unit panel is performed through a scribe process of forming a cut line on the surface of a substrate using a diamond pen having a hardness higher than that of glass, and a break process of applying mechanical force to cut the unit panel. .

Then, liquid crystal is injected into the cut unit panel, and the injection hole is sealed.

In general, in the manufacturing process of the initial liquid crystal display device, liquid crystals are injected into a plurality of liquid crystal panels and then cut into a unit panel. However, as the size of the unit panel increases, a method of cutting a unit panel and then injecting liquid crystals is used.

The unit liquid crystal panel as described above will be described in detail with reference to the accompanying drawings.

FIG. 1 is a plan view schematically illustrating a general liquid crystal display, and is an exemplary view showing a schematic plan structure of a unit liquid crystal panel in which a thin film transistor array substrate and a color filter substrate are opposed to each other.

Referring to FIG. 1, the liquid crystal panel 100 includes an image display unit 113 in which liquid crystal cells are arranged in a matrix, through gate lines 108 and gate pad link units 118 of the image display unit 113. And a data pad portion 115 connected through the gate pad portion 114 and the data lines 107 and the data pad link portion 119. In this case, the gate pad part 114 and the data pad part 115 are formed in the edge region of the lower substrate 101 which does not overlap the upper substrate 102, and the gate pad part 114 is supplied from the gate driver integrated circuit. The gate signal to be supplied to the gate lines 108 of the image display unit 113, and the data pad unit 115 supplies the data signal supplied from the data driver integrated circuit to the data lines 107 of the image display unit 113. Supply.

Although not shown in detail in the drawing, data lines 107 to which image information is applied and gates 108 to which a gate signal is applied are vertically intersected on the lower substrate 101 of the image display unit 113. And a thin film transistor for switching the liquid crystal cells at the intersection thereof, a pixel electrode connected to the thin film transistor to drive the liquid crystal cell, and a protective film formed on the front surface to protect the thin film transistor.

In addition, the upper substrate 102 of the image display unit 113 includes color filters separated and applied to each cell region by a black matrix, and a common transparent electrode serving as a counter electrode of the pixel electrode formed on the lower substrate 101. do.

The lower substrate 101 and the upper substrate 102 configured as described above are provided with a cell-gap by spacers and a sealing portion 116 coated with a sealing material on the outside of the image display portion 113. By the liquid crystal is filled in the cell gap.

However, in the structure of the liquid crystal display device as described above, a defect occurs due to a short circuit between the lines after completion of the thin film transistor or the liquid crystal cell. In particular, a data line formed in the data pad unit 115 and the image display unit 113 ( In the data pad link unit 119 to which the 107 is connected, a short circuit between the data lines 107 mainly occurs.

2 is an enlarged view of a data link unit 119 connected to a data pad unit 115 and a data line 107 formed on the pixel display unit 113.

As shown in the drawing, since the separation distance between the data lines becomes narrower toward the data line 117 of the data line 107 formed in the data pad link unit 119, the short circuit is shorter than other lines between the data lines 107. The probability of occurrence is high.

However, although the possibility of a short circuit between the data lines 107 is high in the data pad link unit 119, it is difficult to find the location thereof.

Accordingly, the present invention has been made to solve the above-described problems, and an object of the present invention is to provide a repair line with a gate electrode material on a data line of a data pad link portion, so that a repair can be performed when a short circuit occurs in this region. The present invention provides a liquid crystal display and a repair method thereof.

Other objects and features of the present invention will be described in detail in the configuration and claims of the following invention.

1 is a plan view schematically showing a conventional liquid crystal display.

FIG. 2 is an enlarged view of a data link unit connecting the data pad unit and the pixel display unit in FIG. 1; FIG.

3 is a view showing a liquid crystal display device according to the present invention.

4 is an enlarged view of the data pad link unit in FIG. 3; FIG.

5 is a cross-sectional view taken along the line AA ′ of FIG. 4.

6 is a diagram illustrating a repair method according to the present invention when a data line short circuit occurs between data lines in a data pad link unit.

*** Explanation of symbols for main parts of drawing ***

207: gate line 208: data line

214: gate pad 215: data pad

218: gate pad link portion 219: data pad link portion

220: repair line

As described above, a liquid crystal display device includes a plurality of gate lines and data lines, an image display unit in which unit pixels defined by the gate lines and data lines are arranged in a matrix form, and the gate lines. A gate pad for supplying a gate signal to the data line, a data pad for supplying a data signal to the data line, a gate pad link unit connecting the gate line and the gate pad, and a data pad link connecting the data line and the data pad And a repair line formed in the data pad link portion to repair a short circuit between data lines.

The repair line is formed such that both ends of the repair line overlap the data line and are made of a gate line material.

In order to repair a short circuit between data lines in the data pad link unit, a repair is performed at the end of the repair line overlapping the data line and the data line through a laser, and then the data line in the region where the repair line is connected. Cut using a laser.

Hereinafter, the liquid crystal display of the present invention as described above will be described in detail with reference to the accompanying drawings.

3 illustrates a liquid crystal display of the present invention in which a repair line of a data line is formed. In particular, FIG. 3 illustrates only a lower substrate on which a thin film transistor array is formed.

As shown in the drawing, the liquid crystal display 200 according to the present invention includes a plurality of gate lines 207 formed in parallel in the horizontal direction on a transparent insulating substrate 201 formed of a material such as glass, and the gate lines. A plurality of data lines 208 formed in a direction perpendicular to 207, an image display unit 213 defined by the gate lines 207 and the data lines 208, and in which unit pixels are arranged in a matrix form, and A gate pad 214 for supplying a gate signal to the gate line 207, a data pad 215 for supplying a data signal to the data line 208, and a gate pad 207 and a gate pad 214. A gate pad link unit 218 electrically connected to each other, and a data pad link unit 219 electrically connecting the data line 208 and the data pad 215 to the data pad link unit 219. Data la A repair line 220 is formed to solve a short circuit between the phosphors 208.

In addition, a gate driver integrated circuit (not shown) for supplying a gate signal to the gate pad unit 214 and a data driver integrated circuit (not shown) for supplying a data signal to the data pad unit 215 are further included. do.

In addition, a thin film transistor (not shown), which is a switching element, is formed at an intersection point of the gate line 207 and the data line 208, and the thin film transistor includes a gate electrode, a gate insulating film, a semiconductor layer, a source electrode, and a drain electrode. Is done. The gate electrode branches at the gate line 207 and the source electrode branches at the data line 208. The drain electrode of the thin film transistor is electrically connected to a pixel electrode (not shown) of a pixel defined by each gate line 207 and data line 208.

In addition, when a short circuit defect occurs between the data lines 208 in the data pad link unit 219 to which the data pads 215 and the data lines 208 arranged in the vertical direction on the image display unit 213 are connected, this is to be avoided. A repair line 220 that can be repaired is formed separately, and the repair line 220 is formed of a "c" model in which both ends of the repair line overlap with the data line.

A repair line structure and a method of repairing the repaired line when the data line is shorted will be described in detail with reference to FIG. 4, which shows an enlarged view of the data pad link unit 219 on which the repair line is formed.

As mentioned in the related art, when a short circuit occurs between the data lines in the data pad link unit 219 to which the data line 208 and the data pad 215 of the image display unit 213 are connected, the position of the short circuits can be accurately known. There was a problem that was difficult to repair. Therefore, in order to solve such a problem, the present invention separately forms a repair line 220 of the "c" model next to the data line 208. That is, as shown in FIG. 4, the repair line 220 is formed together in the gate line process, and is formed of a gate electrode material, and both ends thereof overlap the data line 219. In addition, a gate insulating film (not shown) is interposed between the data line 208 and the repair line 220, and is insulated from each other with a gap therebetween.

FIG. 5 is a cross-sectional view taken along the line AA ′ of FIG. 4.

As shown in the figure, a repair line 220 made of a transparent insulating substrate 200 gate electrode material formed of a material such as glass is formed, and a gate is formed on the entire surface of the substrate 201 including the repair line 220. The insulating film 230 is formed. The data line 208 is formed on the gate insulating layer 230 so as to overlap both ends of the repair line 220, and the passivation layer 240 is formed on the entire surface of the substrate on which the data line 208 is formed. . The data line 208 and the repair line 220 are insulated from each other by the gate insulating layer 230.

In the present invention having the structure as described above, when a short circuit occurs between the data lines 208 in the data pad link unit 219, the repair line 220 and the data line 208 adjacent to the overlapping region are cut off, Both ends of the repair line 220 overlapping the data line 208 are electrically connected to the data line 208 and the repair line 220 by using a laser, so that the data lines between the data lines generated in the truncated data line region are separated. Short circuit failure can be solved. That is, as illustrated in FIG. 6, the data line 208 adjacent to both ends of the repair line 220 is cut by using a laser. The region where the data line 208 is cut is an area where short circuits and neighboring data lines are generated. In this case, short-circuit defects between the data lines may be solved, but the data line 208 may be disconnected, thereby causing a problem in that the data signal is not transmitted. Accordingly, the repair line 220 and the data line 208 are electrically connected to each other by welding the data line 208 of the portion overlapping both ends of the repair line 220 with a laser, with the gate insulating film 230 therebetween. The cut data line 208 is connected to the repair line 220.

As described above, according to the present invention, a repair line made of a gate electrode material is provided in the data pad link portion, and when a short circuit occurs between the data lines, the repair line and the data line adjacent to both ends of the repair line are cut by using a laser, and then the gate insulating film. The short circuit between the data lines can be solved by welding a data line of a portion overlapping with both ends of the repair line with a laser, and electrically connecting the repair line and the data line to each other. By solving the short circuit failure of the data line, there is an effect that can reduce the defective rate of the product.

Claims (8)

A plurality of gate lines formed in parallel in the horizontal direction; A plurality of data lines perpendicular to the gate lines; An image display unit in which unit pixels defined by the gate line and the data line are arranged in a matrix form; A gate pad supplying a gate signal to the gate line; A data pad supplying a data signal to the data line; A gate pad link unit electrically connecting the gate line and a gate pad; A data pad link unit electrically connecting the data line and the data pad to each other; And a repair line formed in the data pad link region corresponding to each data line and having both ends overlapping the data line to repair a short circuit failure between adjacent data lines. The semiconductor device of claim 1, further comprising a gate driver integrated circuit connected to the gate pad to supply a gate signal to a gate line, and a data driver integrated circuit connected to the data pad to supply a data signal to the data line. A liquid crystal display device, characterized in that. The thin film transistor of claim 1, wherein a gate electrode branched from the gate line, a gate insulating layer, a semiconductor layer, a drain electrode, and a source electrode branched from the data line are formed in an intersection region of the gate line and the data line. Liquid crystal display device. The liquid crystal display of claim 1, wherein the repair line is made of a gate electrode material. The liquid crystal display device according to claim 1, wherein the repair line has a "-" shape. 4. The liquid crystal display device according to claim 3, wherein the data line and the repair line are insulated with a gate insulating film. delete A plurality of gate lines formed in parallel in a horizontal direction, a plurality of data lines perpendicularly intersecting the gate lines, an image display unit defined by the gate lines and data lines, and in which unit pixels are arranged in a matrix form, and the gates A gate pad for supplying a gate signal to a line, a data pad for supplying a data signal to the data line, a gate pad link unit electrically connecting the gate line and the gate pad, and electrically connecting the data line and the data pad A liquid crystal display including a data pad link unit connected thereto and a repair line formed at both ends of the data pad link unit to overlap each other, wherein data lines adjacent to each other are electrically connected to each other. In case of short circuit failure, Repairing the short circuit failure, Cutting two points of the data line adjacent to both ends of the repair line to insulate the neighboring data line; And electrically connecting the cut data line through the repair line by irradiating a laser to an overlapping area of the repair line and the data line, and electrically connecting the repair line with the repair line.