KR101033119B1 - Line on Glass Liquid Crystal Display - Google Patents

Abstract

The present invention relates to a line on glass type liquid crystal display device.

Recently, a line on glass (LOG) method for directly connecting a gate driving circuit and a data driving circuit on an array substrate has been proposed and used. A problem is that a signal is not properly transferred due to a bad contact in a LOG wiring adjacent to a data pad. There is.

In the present invention, a dummy pad is formed and the same signal is applied by connecting the dummy pad to the LOG wiring adjacent to the data pad. Therefore, even if a contact failure occurs in the LOG wiring adjacent to the data pad, disconnection of the signal can be prevented.

Description

Line on glass-type liquid crystal display device             

1 is a view schematically showing a liquid crystal display device using a conventional line on glass method.

FIG. 2 is an enlarged view of region C in FIG. 1. FIG.

3 is a cross-sectional view taken along the line III-III of FIG. 2.

4 is a diagram illustrating a line on glass type liquid crystal display device according to the present invention;

5 is a cross-sectional view taken along the line V-V in FIG. 4.

6 is a cross-sectional view taken along the line VI-VI in FIG. 4.

<Description of Symbols for Main Parts of Drawings>

114a: data pad 115a: first contact hole

115b: second contact hole 116: conductive pattern

140: data TCP 146: data output terminal

148: gate signal transmission wiring 162: LOG wiring

164: Dummy Pads

The present invention relates to a liquid crystal display device, and more particularly, to a line on glass type liquid crystal display device.

Recently, with the rapid development of the information society, there is a need for a flat panel display having excellent characteristics such as thinning, light weight, and low power consumption. Among them, a liquid crystal display has a resolution, It is excellent in color display and image quality, and is actively applied to notebooks and desktop monitors.

In general, a liquid crystal display device arranges two substrates on which electrodes are formed so that the surfaces on which the two electrodes are formed face each other, injects a liquid crystal material between the two substrates, and applies a voltage to the two electrodes to generate an electric field. By moving the liquid crystal molecules, the image is expressed by the transmittance of light that varies accordingly.

The liquid crystal display device includes a liquid crystal panel in which liquid crystal is injected between two substrates, a backlight disposed under the liquid crystal panel and used as a light source, and a driving unit for driving the liquid crystal panel, which is located outside the liquid crystal panel.

Here, the driving unit includes a driving circuit (hereinafter referred to as a drive integrated circuit (IC)) for applying a signal to the wiring of the liquid crystal panel, and chip-on-glass according to a method of packaging the drive IC in the liquid crystal panel. (COG: chip on glass), tape carrier package (TCP), chip on film (COF).

The COG method is a method in which a driver IC is attached to an array substrate of a liquid crystal display device and directly connects an output electrode of the driver IC to a wiring pad on the array substrate. The COG method is simple in structure and simple in manufacturing. There is an advantage. On the other hand, when using the COG method, in order to simplify the structure and manufacturing process of the flexible printed circuit (FPC), the line on glass (lines on glass) directly connecting the gate driver IC and the data driver IC on the array substrate A method called "LOG" has been proposed and used.

Recently, even when TCP is connected to a liquid crystal panel using a TAB (tape automated bonding) method, the LOG method is used, so that a liquid crystal display device can be further thinned by removing a printed circuit board (PCB).

The structure of the liquid crystal display device using the LOG method is illustrated in FIG. 1. As shown, the liquid crystal display includes a lower substrate 10 and an upper substrate 20 in which a display area A in which an image is displayed and a non-display area B around the display area A are defined. A liquid crystal layer (not shown) is inserted between the lower substrate 10 and the upper substrate 20. In addition, the LCD device includes a plurality of gate TCPs 30 attached to one side of the lower substrate 10 and a plurality of data TCPs 40 and data TCPs 40 attached to the other side. ).

On the lower substrate 10 of the display area A, a gate line 12 in the horizontal direction and a data line 14 in the vertical direction are formed, and the gate line 12 and the data line 14 intersect with each other. Define. The thin film transistor 16 is formed at the intersection of the gate line 12 and the data line 14 to be connected to the gate line 12 and the data line 14, and is connected to the thin film transistor 16 in the pixel region. A pixel electrode is formed. The pixel electrode becomes one electrode of the liquid crystal capacitor 18.

Gate pads and data pads extending from the gate wiring 12 and the data wiring 14 are formed on the lower substrate 10 of the non-display area B, and the gate driving signal is transmitted to the gate drive IC 32. LOG wiring 62 is formed.

A data drive IC 42 is mounted on the data TCP 40, and a data input terminal 44 and a data output terminal 46 electrically connected to the data drive IC 42 are formed. The data input terminal 44 is electrically connected to an output terminal (not shown) of the data PCB 50, and the data output terminal 46 is connected to a data pad on the lower substrate 10. Here, the data PCB 50 is formed of a plurality of devices such as an integrated circuit on the substrate, and generates various control signals and data signals for driving the liquid crystal panel.

On the other hand, a gate signal transmission wiring 48 is formed in the first data TCP 40, and the gate signal transmission wiring 48 is connected to the LOG wiring 62 to log gate driving signals supplied from the data PCB 50. It transfers to the wiring 62.

A gate drive IC 32 is mounted on the gate TCP 30, and a gate output terminal 34 and a signal transmission wiring 36 electrically connected to the gate drive IC 32 are formed. The gate output terminal 34 is electrically connected to the gate pad, and the signal transmission wiring 36 is electrically connected to the LOG wiring 62.

The LOG wiring 62 is formed in a fine pattern on the outer side of the display area A together with the pads. In general, FPC is made of copper, which is a metal having a very low specific resistance. Therefore, the LOG wiring 62 instead of the FPC should also be made of a material having a small resistance, and the width of the pattern and the length should be short. Relatively small resistance materials include aluminum or aluminum alloy materials. Recently, as the screen is enlarged, gate wiring is formed using aluminum or aluminum alloy to prevent signal delay. Therefore, in order to reduce the number of steps while reducing the resistance of the LOG wiring 62, the LOG wiring 62 can be formed in the same process as the gate wiring.

FIG. 2 is an enlarged plan view of the LOG wiring and corresponds to an enlarged view of region C in FIG. 1. As shown, the data TCP 40 includes a plurality of data output terminals 46 and gate signal transmission wirings 48. The data output terminal 46 is connected to the data pad 14a and the gate signal transmission wiring 48 is connected to the LOG wiring 62. By the way, since the LOG wiring 62 is made of the same material as the gate wiring (12 of FIG. 1), and the data pad 14a is made of the same material as the data wiring (14 of FIG. 1), Adjacent LOG wiring 62 may not be properly contacted with the gate signal transmission wiring 48, which may cause a defect.

3 is a cross-sectional view taken along the line III-III of FIG. 2. As illustrated, a plurality of LOG wirings 62 made of a material such as a gate wiring is formed on the transparent insulating substrate 10, and an insulating pattern 13 is formed adjacent to the LOG wiring 62. The data pad 14a is formed on the top. The insulating pattern 13 corresponds to a gate insulating film, which covers most of the LOG wiring 62, but the LOG wiring 62 transmits the gate signal at a portion where the LOG wiring 62 overlaps with the data TCP 40. It is removed to be in contact with the wiring 48. The LOG wiring 62 is in contact with the gate signal transmission wiring 48 of the data TCP 40, and the data pad 14a is in contact with the data output terminal 46.

Here, since the insulating pattern 13 is formed under the data pad 14a, the LOG wiring 62 and the data pad 14a are positioned at different positions. The gate signal transmission wiring 48 and the data output terminal ( Since the 46 is formed on the same surface, the portion of the data TCP 40 is bent between the gate signal transmission wiring 48 and the data output terminal 46. At this time, the area D adjacent to the data pad 14a is formed. There is a problem that the LOG wiring 62 is not in proper contact with the gate signal transmission wiring 48. Further, even when the LOG wiring 62 is in contact, contact failure may occur due to heat or other external factors.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide a line on glass type liquid crystal display device which can prevent disconnection of a signal due to poor contact of a LOG wiring.

A line-on-glass liquid crystal display according to the present invention for achieving the above object is an insulating substrate defined by a display area and a non-display area, and formed on the display area, intersect to define a pixel area, A plurality of gate wirings and data wirings each having a pad, a thin film transistor connected to the gate wiring and a data wiring, a pixel electrode in the pixel area, and a pixel electrode connected to the thin film transistor, and a non-display area. A gate driver and a data driver for applying signals to the gate wiring and the data wiring, a plurality of line-on-glass wirings positioned on the non-display area and transferring a gate driving signal from the data driver to the gate driver; A first data pad connected to the data driver Adjacent line-on-glass-shaped line-on-glass liquid crystal display device that is formed and the dummy wiring pad including the dummy pad, and a is electrically connected to the interposed between the glass-shaped wires on the line to the data pad part and the other side.

Here, the same signal is applied to the line-on-glass wiring and the dummy pad adjacent to the first data pad.

The plurality of line-on-glass wiring and the dummy pad may be made of the same material as the gate wiring.

The present invention may further include a conductive pattern connecting the line-on-glass wiring and the dummy pad adjacent to the first data pad, and the conductive pattern may be formed of the same material as the pixel electrode. The semiconductor device may further include an insulating layer covering the line-on-glass wiring and the dummy pad adjacent to the first data pad, wherein the conductive pattern is a line-on-glass wiring and the dummy pad adjacent to the first data pad through a contact hole formed in the insulating layer. And a short circuit to the line-on-glass wiring and the dummy pad adjacent to the first data pad by a laser.

There are two dummy pads, and each of the dummy pads may be electrically connected to two line-on-glass wirings adjacent to the first data pad, and the signals applied to the dummy pads may be gate high voltage signals V _GH and gate low voltage signals, respectively. (V _GL ).

As described above, in the present invention, by forming the dummy pad and connecting the dummy pad with the line on glass type wiring adjacent to the data pad, it is possible to prevent signal disconnection even if a contact failure occurs in the line on glass type wiring.

4 is a view illustrating a line-on-glass type liquid crystal display device according to the present invention. The liquid crystal display device of the present invention has the same structure as the conventional one, except for the line-on-glass type (hereinafter referred to as LOG) wiring portion. Only the LOG wiring part is shown. As illustrated, a plurality of data pads 114a connected to data wires (not shown) are formed outside the lower substrate of the liquid crystal display, and a plurality of LOG wires 162 are adjacent to the first data pad 114a. ) Is formed. In addition, a dummy pad 164 is formed adjacent to the LOG wiring 162. The LOG wiring 162 and the dummy pad 164 are made of the same material as the gate wiring (not shown). Here, two dummy pads 164 may be provided, and two LOG wires 162 adjacent to the data pads 114a may be electrically connected to the dummy pads 164 through the conductive patterns 116, respectively. ) Is connected to the dummy pad 164 through the first contact hole 115a and to the LOG wiring 162 through the second contact hole 115b.

On the other hand, the data TCP 140 including the plurality of data output terminals 146 and the gate signal transmission wiring 148 is arranged to overlap the data pad 114a, the LOG wiring 162 and the dummy pad 164. . The data output terminal 146 is connected to the data pad 114a, and the gate signal transmission wiring 148 is connected to the LOG wiring 162 and the dummy pad 164.

The LOG wiring 162 includes a plurality of signal wirings, each of which includes a gate high voltage signal V _GH and a gate low voltage signal V _GL , a common voltage signal V _COM , and a ground voltage signal GND. ), A power supply voltage signal VCC, a gate start pulse GSP, a gate shift clock signal GSC, and a gate enable signal GOE.

5 is a cross-sectional view taken along the line V-V in FIG. 4, and FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. 4. As illustrated, a plurality of LOG lines 162 and dummy pads 164 are formed on the transparent insulating substrate 110. The LOG wiring 162 and the dummy pad 164 are made of the same material in the same process as the gate wiring (not shown). Subsequently, a gate insulating layer 113 is formed to cover the LOG wiring 162 and the dummy pad 164, and the gate wiring 162 and the dummy pad 164 are connected to the gate signal transmission wiring 148 at the gate. The insulating film 113 is removed to expose the LOG wiring 162 and the dummy pad 164. A data pad 114a connected to a data line (not shown) is formed on the gate insulating layer 113, and the data pad 114a is spaced apart from the LOG line 162. Next, the passivation layer 115 covers the substrate 110 including the data pads 114a. The passivation layer 115 together with the gate insulating layer 113 exposes the dummy pad 164 and the LOG wiring 162, respectively. It has the 1st and 2nd contact hole 115a, 115b. In addition, the passivation layer 115 exposes one end of the data pad 114a, the LOG wiring 162, and the dummy pad 164. Next, a conductive pattern 116 is formed on the passivation layer 115, and the conductive pattern 116 is connected to the dummy pad 164 through the first contact hole 115a and through the second contact hole 115b. It is connected to the LOG wiring 162. Therefore, the dummy pad 164 and the LOG wiring 162 are electrically connected to each other. Here, the case in which the conductive pattern 116 is connected to the dummy pad 164 and the LOG wiring 162 through the contact holes 115a and 115b has been described, but the laser is not formed without forming the contact holes 115a and 115b. The conductive pattern 116 may be short-circuited with the dummy pad 164 and the LOG wiring 162 by use.

The exposed data pad 114a is connected to the data output terminal 146 of the data TCP 140, and the LOG wiring 162 and the dummy pad 164 are connected to the gate signal transmission wiring 148 of the data TCP 140. Connected.

In the present invention, the same signal as that of the LOG wiring 162 connected through the conductive pattern 116 is applied to the dummy pad 164. In this case, the signal applied to the dummy pad 164 and the LOG wiring 162 connected thereto may be a gate high voltage signal V _GH and a gate low voltage signal V _GL . Therefore, as shown in FIG. 6, even if a contact failure occurs between the LOG wiring 162 and the gate signal transmission wiring 148 in the area E adjacent to the data pad 114a, the area away from the data pad 114a. Since the dummy pad 164 located at (F) and the gate signal transmission wiring 148 are well in contact with each other, a normal screen may be displayed by transmitting a signal through the dummy pad 164.

The present invention is not limited to the above embodiments, and various changes and modifications can be made without departing from the spirit of the present invention.

In the line-on-glass type liquid crystal display according to the present invention, by forming a dummy pad that receives the same signal as the LOG wiring adjacent to the data pad and connecting the same with the LOG wiring, the signal is disconnected even if a bad contact occurs in the LOG wiring adjacent to the data pad. Can be prevented and a normal screen can be displayed.

Claims (9)

An insulating substrate defined by a display area and a non-display area; A plurality of gate lines and data lines formed on the display area and defining pixel areas crossing each other and having pads at one end thereof; A thin film transistor connected to the gate line and the data line; A pixel electrode positioned in the pixel region and connected to the thin film transistor; A gate driver and a data driver positioned on the non-display area and respectively applying a signal to the gate line and the data line; A plurality of line-on-glass wirings positioned on the non-display area and transferring a gate driving signal from the data driver to the gate driver; A dummy pad connected to the data driver and electrically connected to a line on glass type wiring adjacent to a first data pad, wherein the dummy pad is formed on the other side of the data pad with the line on glass type wiring interposed therebetween. Line-on-glass type liquid crystal display device. The method of claim 1, And a same signal is applied to the line-on-glass wiring and the dummy pad adjacent to the first data pad. The method of claim 1, And the plurality of line on glass type wirings and dummy pads are made of the same material as the gate line. The method of claim 1, And a conductive pattern connecting the line-on-glass wiring and the dummy pad adjacent to the first data pad. The method of claim 4, wherein And the conductive pattern is formed of the same material as the pixel electrode. The method of claim 4, wherein And an insulating layer covering the line on glass type wiring adjacent to the first data pad and the dummy pad, wherein the conductive pattern is connected to the line on glass type wiring and the dummy pad adjacent to the first data pad through a contact hole formed in the insulating layer. Line on glass liquid crystal display. The method of claim 4, wherein And an insulating layer covering the line-on-glass-type wiring adjacent to the first data pad and the dummy pad, wherein the conductive pattern is shorted by the laser to the line-on-glass-type wiring adjacent to the first data pad and the dummy pad. Type liquid crystal display device. The method of claim 1, And two dummy pads, each of which is electrically connected to two line-on-glass wirings adjacent to the first data pad. The method of claim 8, And a signal applied to the dummy pad is a gate high voltage signal V _GH and a gate low voltage signal V _GL, respectively.

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