KR20060011587A - Liquid Crystal Display and Manufacturing Method Thereof - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device (LCD), and to a liquid crystal display device having a structure for preventing corrosion of a pad portion and a manufacturing method thereof.

A liquid crystal display device according to the present invention includes: first and second substrates; A thin film transistor formed at an intersection thereof with the gate and data wiring crossing each other on the first substrate to define a pixel region; A gate and data pad part formed on the second substrate; A sealant which vacuum-bonds the first and second substrates to conduct the gate and data pad portions to the gate and data wires; And a liquid crystal layer formed between the first and second substrates.

Therefore, the present invention prevents the pad part corrosion to produce a good quality product to improve the reliability, the low resistance wire to implement the pad part low resistance wiring in a large-area product range, the pad part corrosion can be improved, manufacturing yield Has the effect of improving.

Pad, corrosion, corrosion, sealant

Description

Liquid crystal display device and method for manufacturing same

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

2 is a cross-sectional view schematically illustrating an array substrate of a conventional liquid crystal display.

3 is a plan view of a liquid crystal display device according to the present invention;

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

FIG. 5 is a cross-sectional view taken along line II-II ′ of FIG. 3.

<Description of Signs of Major Parts of Drawings>

310: array substrate 312: gate wiring

320: color filter substrate 321: black matrix

322: gate electrode 325: data pad

326: gate pad 330: gate insulating film

331: color filter 341: active layer

343: common electrode 344, 345: common electrode pattern

351, 352: ohmic contact layer 360: sealant

361: source electrode 362: drain electrode

365: capacitor electrode 370: protective layer                 

371: first contact hole 372: second contact hole

388: gate transparent electrode pattern 389: data transparent electrode pattern

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device (LCD), and to a liquid crystal display device having a structure for preventing corrosion of a pad portion and a manufacturing method thereof.

Recently, with the development of the electronics industry, display devices, which have been limitedly used for TV CRTs, have been widely used in personal computers, notebooks, wireless terminals, automobile dashboards, electronic displays, etc. As a result, the importance of the next generation display device that can process and implement this is increasing.

Such next-generation display devices should be able to realize light and small size, high brightness, large screen, low power consumption, and low price.In response, recently, LCD, Plasma Display Panel (PDP), Electro Luminescent Display (ELD), and VFD (Vacuum Fluorescent Display) Various flat panel display devices have been studied, and one of them has recently attracted attention.

The liquid crystal display device is superior in resolution to other flat panel display devices, and exhibits characteristics such that the response speed is faster than that of a CRT when a moving image is realized.

In addition, the liquid crystal display device has excellent characteristics such as high brightness, high contrast, low power consumption, and so is used in a wide range of fields such as a desktop computer monitor, a notebook computer monitor, a TV receiver, a vehicle-mounted TV receiver, and navigation.

In general, a liquid crystal display device is formed by arranging two substrates having electrodes formed on one side thereof so that the surfaces on which the two electrodes are formed face each other, injecting a liquid crystal material between the two substrates, and then applying voltage to the two electrodes. By moving the liquid crystal molecules by the electric field is a device that represents the image by the transmittance of light that varies accordingly.

Such a liquid crystal display device may be broadly divided into a liquid crystal panel displaying an image and a driving unit for applying a driving signal to the liquid crystal panel, wherein the liquid crystal panel includes first and second substrates bonded to each other with a predetermined space; It consists of a liquid crystal layer injected between the two substrates.

Here, the first substrate (hereinafter referred to as an array substrate) may include a plurality of gate lines arranged in one direction at a predetermined interval, and a plurality of data lines arranged at regular intervals in a direction perpendicular to the respective gate lines; And a plurality of pixel electrodes formed in a matrix form in each pixel region defined by crossing each of the gate lines and the data lines and the signals of the gate lines to transfer the signals of the data lines to the pixel electrodes. Thin film transistors are formed.

The second substrate (hereinafter referred to as a color filter substrate) includes a black matrix layer for blocking light in portions other than the pixel region, a color filter layer for expressing color colors, and a common electrode for implementing an image. do.

The conventional liquid crystal panel will be described in detail as follows.

1 is a plan view illustrating a conventional liquid crystal display device.

Referring to FIG. 1, a conventional liquid crystal display device includes an image display unit 196 including a pixel matrix, a data driver 192 for driving data lines 104 of the image display unit 196, A gate driver 192 for driving the gate lines 102 of the image display unit 196 is provided.

In the image display unit 196, liquid crystal cells are arranged in a matrix to display an image.

Each of the liquid crystal cells is driven by a thin film transistor (TFT) as a switching element connected to the intersection of the gate wiring 102 and the data wiring 104.

The n-type thin film transistor 130 causes the liquid crystal cell to charge the video signal from the data line 104, that is, the pixel signal, in response to a scan pulse from the gate line 102. The liquid crystal cell adjusts the light transmittance according to the charged pixel signal.

The gate driver 194 sequentially drives the gate lines 102 by a horizontal period for each frame by gate control signals.

The thin film transistors are sequentially turned on in the horizontal wiring unit by the gate driver 194 to connect the data wiring 104 to the liquid crystal cell.

The data driver 192 samples a plurality of digital data signals every horizontal period and converts the digital data signals into analog data signals.

The data driver 192 supplies an analog data signal to the data lines 104.

Accordingly, the liquid crystal cells connected to the turned-on thin film transistors adjust light transmittance in response to data signals from each of the data lines 104.

The gate driver 194 and the data driver 192 may include driving devices connected in a CMOS structure.

The driving device is composed of one large thin film transistor having a large channel width W1 so that a relatively large amount of current can flow for switching of a relatively high voltage.

Such a driving device uses poly-silicon for fast response speed.

In this way, the gate electrode 102, the data wire 104, and the gate electrode and the source / drain electrode constituting the thin film transistor 130 formed on the array substrate of the liquid crystal panel are formed of metal to improve the signal transfer speed. .

In general, in the array substrate of the liquid crystal display device, the gate wiring 102 and the data wiring 104 are required to suppress signal delay and disconnection as means for transmitting scan signals and data signals, respectively.

Therefore, the material used as the wiring layer is a low-resistance metal such as aluminum (Al), aluminum alloy (Al alloy), molybdenum (Mo), copper (Cu), etc. having a low resistivity of 15μΩcm ^-1 or less to prevent signal delay Suitable, in particular, aluminum or AlNd is generally used.

The aluminum (Al) is widely used in various industrial materials because of its good workability, low corrosion resistance, and low density. In particular, aluminum (Al) has a resistance of 3 to 6 μΩcm ^-1 , and when applied to a display device, a large screen can be made and high quality can be obtained. Can be achieved.

However, its physical properties are weak, and when exposed to air, an oxide film (Al ₂ O ₃ ) is formed on its surface by the external diffusion of aluminum ions and the internal diffusion of oxygen ions, and in contact with ITO, a transparent pixel electrode. There is a problem that the contact portion is oxidized by oxygen in the ITO and the electrical resistance value is increased.

Therefore, since the wiring is formed only by the aluminum (Al) layer, the characteristics of the device are deteriorated. Therefore, the specific resistance is as small as 12 to ¹⁴ µΩcm ^-1 and the contact property with ITO is not bad and can be used alone as the wiring. Is formed in a double wiring structure with AlNd.

Hereinafter, the liquid crystal display device which has the low resistance wiring of the double wiring structure as above is demonstrated.                         

2 is a cross-sectional view schematically illustrating an array substrate of a conventional liquid crystal display.

As shown in FIG. 2, the gate electrode 222 extending from the horizontal wiring line 221, the gate electrode 222 extending from the gate wiring 221, and a gate positioned at one end of the gate wiring (not shown) on the substrate 210. The pad 223 is formed.

The gate electrode 222 is made of a barrier metal / low resistance metal 222a / 222b, and the gate pad 223 is also made of a barrier metal / low resistance metal 223a / 223b.

In this case, AlNd is generally used as the barrier metals 222a and 223a.

As the low resistance metal, molybdenum (Mo) is generally used.

A gate insulating layer 230 is formed on the gate line, the gate electrode 222, and the gate pad 223, and an active layer 241 is formed thereon.

The gate insulating film 230 is formed by depositing an insulating material of silicon nitride (SiNx) or silicon oxide (SiOx) on the substrate 210.

In addition, an amorphous silicon layer and an amorphous silicon layer doped with impurities are sequentially stacked on the gate insulating layer 230 by using a chemical vapor deposition method (hereinafter, referred to as 'CVD').

The amorphous silicon layer and the amorphous silicon layer doped with impurities are patterned by photolithography to form the active layer 241 and the ohmic contact layers 251 and 252.                         

The source electrode 262 is formed on the ohmic contact layers 251 and 252 with the data wiring 261 orthogonal to the gate wiring, the source electrode 262 extending from the data wiring 261, and the gate electrode 222. ) And a data pad 264 positioned at one end of the data line 261.

Here, a triple structure of a first barrier metal / low resistance metal / second barrier metal or a double structure of a barrier metal / low resistance metal to form the source and drain electrodes 262 and 263 and the data pad 264. It can be formed by laminating.

Subsequently, a protective layer 270 covers the data line 261, the source and drain electrodes 262 and 263, and the data pad 264 on the entire surface of the substrate 210, and the protective layer 270 is a drain electrode ( A second contact hole 271 having a first contact hole 271 exposing the 263 and a third contact hole 274 exposing the data pad 264 and exposing the gate pad 223 together with the gate insulating film 230. 273).

The pixel electrode 281, the auxiliary gate pad 282, and the auxiliary data pad 283 are formed on the passivation layer 270.

The pixel electrode 281 is connected to the drain electrode 263 through the first contact hole 271, and the auxiliary gate pad 282 and the auxiliary data pad 283 are connected to the second and third contact holes 273, 274 is connected to the gate pad 223 and the data pad 264, respectively.

At this time, the pad portion for connecting to the external driving circuit is exposed to the outside during the process is long, there is a problem that the pad portion is corroded during the process, which causes a problem of increasing the contact resistance and wiring resistance.

SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid crystal display device and a method for manufacturing the same, in which a pad part electrode is formed on a color filter substrate and a pad is connected to the array substrate using a sealant to prevent corrosion of the pad part. have.

In order to achieve the above object, a liquid crystal display device according to the present invention, the first and second substrates; A thin film transistor formed at an intersection thereof with the gate and data wiring crossing each other on the first substrate to define a pixel region; A gate and data pad part formed on the second substrate; A sealant which vacuum-bonds the first and second substrates to conduct the gate and data pad portions to the gate and data wires; And a liquid crystal layer formed between the first and second substrates.

The thin film transistor may include a gate electrode extending from the gate wiring;

A semiconductor layer formed on the gate electrode; And a source electrode and a drain electrode formed on the semiconductor layer at predetermined intervals and extending from the data line.

The sealant is formed by including a conductive ball.

A black matrix covering the gate, the data line and the thin film transistor formed on the second substrate; A color filter formed corresponding to the pixel region; And a common electrode formed on the entire surface of the second substrate.                     

The gate and data pad parts may be formed of a black matrix material.

The black matrix material is characterized in that the metal material.

Further, in order to achieve the above object, a method of manufacturing a liquid crystal display device according to the present invention includes the steps of forming a gate wiring, a data wiring, and a thin film transistor in an effective image display area of a first substrate; Forming a black matrix covering the gate wiring and the data wiring and the thin film transistor in the effective image display area on a second substrate, and forming a gate pad and a data pad in the effective image non-display area; And forming a sealant at a boundary between the effective image display area and the effective image non-display area, bonding the first and second substrates, and forming a liquid crystal layer.

A color filter is formed in the effective image display area on the second substrate.

The gate pad and the data pad formed on the second substrate may be connected to the gate wiring and the data wiring formed on the first substrate.

The sealant is characterized in that it comprises a conductive ball.

Hereinafter, a liquid crystal display according to the present invention will be described in detail with reference to the accompanying drawings.

3 is a plan view of the liquid crystal display according to the present invention, FIG. 4 is a cross-sectional view taken along line II ′ of FIG. 3, and FIG. 5 is a view taken along line II-II ′ of FIG. 3.

3, 4, and 5, in the liquid crystal display, the array substrate 310 and the color filter substrate 320 face each other to form a liquid crystal panel, and the array of the color filter substrate 310 is formed. The outside of the pad is formed with a pad for applying an external drive signal.

The liquid crystal display device is arranged so that the effective substrate display area A and the effective substrate non-display area B forming the periphery of the effective image display area A are defined and the color filter substrate face each other.

A sealant 360 is formed at the boundary between the effective image display area A and the effective image non-display area B to bond the array substrate and the color filter substrate together.

In addition, the liquid crystal layer 350 is interposed in the sealant 360, and the liquid crystal is injected between the pixel electrode 381 of the array substrate 310 and the common electrode 343 of the color filter substrate 320. The molecular arrangement is changed by the voltage difference between the pixel electrode 381 and the common electrode 343. The liquid crystal display is driven by the change in the molecular arrangement.

As such, in order to form the liquid crystal panel, the array substrate 310 and the color filter substrate 320 are vacuum bonded to each other by the sealant 360.

In addition, the sealant 360 may include conductive balls to conduct the pad portions 325 and 326 formed on the color filter substrate 320 and the array substrate 310 to each other.

In this case, the pad parts 325 and 326 formed on the color filter substrate 320 are made of a metal such as chromium (Cr) forming the black matrix 321, and the black matrix 321. ) And pad portions 325 and 326 are formed spaced apart from each other.

First, in the liquid crystal display array substrate 310, a gate wiring 312 having a horizontal direction and a gate electrode 322 extending from the gate wiring 312 are formed on the transparent insulating substrate 310.

Metals forming the gate electrode 322 and the gate wiring 312 may include copper (Cu), silver (Ag), platinum (Pt), gold (Au), titanium (Ti), molybdenum (Mo), and chromium (Cr). ), Tantalum (Ta), W-based metal, aluminum (Al), aluminum alloy (Al Alloy) can be applied.

The gate insulating layer 330 is formed on the gate wiring 312 and the gate electrode 322, and the active layer 341 and the ohmic contact layers 351 and 352 are sequentially formed thereon.

The gate insulating layer 330 is formed of a silicon nitride film (SiN _x ) or a silicon oxide film (SiO ₂ ).

The data line 365 perpendicular to the gate line 312 on the ohmic contact layers 351 and 352, the source electrode 361 extending from the data line 365, and a source around the gate electrode 322. A capacitor electrode 366 overlapping with the drain electrode 362 and the gate wiring 312 facing the electrode 361 is formed.                     

Here, the data line 365, the source and drain electrodes 361 and 362, and the capacitor electrode 366 are covered with a protective layer 370, and the protective layer 370 includes the drain electrode 362 and the capacitor electrode ( And first and second contact holes 371 and 372 exposing 366, respectively.

A pixel electrode 381 made of a transparent conductive material is formed on the passivation layer 370 of the pixel area defined by the gate line 312 and the data line 365 intersecting. The pixel electrode 381 is formed of a first electrode. And a drain electrode 362 and a capacitor electrode 366 through the second contact holes 371 and 372, respectively.

The transparent conductive material is selected from indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), and the like.

The black matrix 321 covering the gate wiring 312, the data wiring 365, and the thin film transistor is formed on the color filter substrate 320 bonded to the array substrate 310 formed as described above.

The black matrix 321 uses an opaque metal such as chromium (Cr).

In addition, a color filter 331 of red, blue, and green color is formed in the color filter substrate 320 corresponding to the pixel area of the array substrate 310.

In this case, the black matrix 321 forms the gate pad 326 and the data pad 325 in the effective image non-display area B, and the gate pad 326 and the data pad 325 are the black matrix 321. Insulated).

The common electrode 343 is formed on the black matrix 321 and the color filter 331.

In addition, predetermined common electrode patterns 344 and 345 are formed on the gate pad 326 and the data pad 325.

Here, the array substrate 310 and the color filter substrate 320 are bonded by the sealant 360. Since the sealant 360 includes conductive balls, the array substrate 310 and the color filter substrate 320 are electrically connected upward and downward.

Therefore, the wiring of the lower array substrate 310 and the upper pad portion are electrically connected to each other by the sealant 360.

That is, the gate wiring 312 of the array substrate 310 and the gate pad 326 of the color filter substrate 320 are contacted by the sealant 360.

The data line 365 of the array substrate 310 and the data pad 325 of the color filter substrate 320 are contacted by the sealant 360.

Therefore, as shown in FIG. 4, the array substrate 310 has a third contact hole penetrating through the gate insulating film 330 and the protective film 370 to contact the gate wiring 312 under the sealant 360. 389 is formed, and a gate transparent electrode pattern 388 is formed in the third contact hole 389.

In addition, as shown in FIG. 5, a fourth contact hole 387 is formed in the array substrate 310 to penetrate the passivation layer 370 to contact the data line 365 under the sealant 360. The data transparent electrode pattern 386 is formed in the fourth contact hole 387.                     

Although the present invention has been described in detail through specific embodiments, this is for explaining the present invention in detail, and a liquid crystal display and a method of manufacturing the same according to the present invention are not limited thereto. It is apparent that modifications and improvements are possible by those skilled in the art.

The present invention has the effect of improving the reliability by producing a good quality product by preventing pad portion corrosion by forming a pad portion using a black matrix on the color filter substrate in the liquid crystal display device and conducting with the array substrate using a sealant.

In addition, the liquid crystal display device according to the present invention implements the pad portion low resistance wiring in the low-resistance wiring in a large-area product range, and can improve the corrosion of the pad portion, thereby improving the manufacturing yield.

Claims (10)

First and second substrates; A thin film transistor formed at an intersection thereof with the gate and data wiring crossing each other on the first substrate to define a pixel region; A gate and data pad part formed on the second substrate; A sealant for vacuum bonding the first and second substrates to conduct the gate and data pad portions to the gate and data wires; And a liquid crystal layer formed between the first and second substrates. The method of claim 1, The thin film transistor, A gate electrode extending from the gate wiring; A semiconductor layer formed on the gate electrode; And a source electrode and a drain electrode formed on the semiconductor layer at predetermined intervals and extending from the data line. The method of claim 1, The sealant is formed by including a conductive ball. The method of claim 1, A black matrix covering the gate, the data line and the thin film transistor formed on the second substrate; A color filter formed corresponding to the pixel region; And a common electrode formed on the entire surface of the second substrate. The method of claim 1, And the gate and data pad portions are made of a black matrix material. The method of claim 5, And the black matrix material is made of a metal material. Forming a gate wiring and a data wiring and a thin film transistor in the effective image display area of the first substrate; Forming a black matrix covering the gate wiring and the data wiring and the thin film transistor in the effective image display area on a second substrate, and forming a gate pad and a data pad in the effective image non-display area; And forming a sealant at a boundary between the effective image display area and the effective image non-display area, bonding the first and second substrates, and forming a liquid crystal layer. The method of claim 7, wherein A color filter is formed in the effective image display area on the second substrate. The method of claim 7, wherein The gate pad and the data pad formed on the second substrate are connected to the gate wiring and the data wiring formed on the first substrate. The method of claim 7, wherein The sealant includes a conductive ball, characterized in that the manufacturing method of the liquid crystal display device.

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