KR101023284B1 - Liquid Crystal Display device and the fabrication method thereof - Google Patents

Abstract

A liquid crystal display device according to the present invention includes first and second substrates that face each other and have a liquid crystal layer formed therebetween, common voltage wirings formed on the first substrate, common electrodes formed on the second substrate, and the first substrate. And a seal pattern formed at an edge between two substrates and at least one silver dot electrically connecting the first and second substrates to the outside of the seal pattern. A plurality of silver dot pad contact holes are formed on the substrate under the seal pattern.

Therefore, in the liquid crystal panel according to the present invention, the silver dot pad contact holes for electrically connecting the first and second substrates through the silver dots are formed under a seal pattern to prevent electrical or corrosion defects causing product defects. And there is an advantage to improve the reliability.

Ag dot, contact hole, electroplating, corrosion, seal pattern

Description

Liquid crystal display device and method for manufacturing same

1 is a schematic plan view of a liquid crystal panel for a general liquid crystal display device;

FIG. 2 is an enlarged view of a portion 'A' of FIG. 1 and is a plan view showing an enlarged portion of a liquid crystal panel for a conventional liquid crystal display. FIG.

3 is a plan view schematically showing a part of a liquid crystal panel for a liquid crystal display device according to the present invention;

FIG. 4 is a cross-sectional view of the liquid crystal panel shown in FIG. 3 taken along line B-B '.

<Description of Signs of Major Parts of Drawings>

210: first substrate 212: common voltage wiring

220: second substrate 222: gate electrode

230: gate insulating film 231: color filter

241 active layer 243 common electrode

250: liquid crystal layer 251, 252: ohmic contact layer

260: seal pattern 261: source electrode

262: drain electrode 266: silver dot (Ag dot)

270: protective layer 271: drain contact hole                 

281 pixel electrode 288 dot pad

289 dot pad contact hole

The present invention relates to a liquid crystal display device (LCD).

In general, CRT (or CRT: Cathode Ray Tube) has been the most used display device for displaying image information on the screen, which is inconvenient to use because it is bulky and heavy compared to the display area. .

In addition, with the development of the electronics industry, display devices, which have been limitedly used in TV CRTs, are widely used in personal computers, laptops, wireless terminals, automobile dashboards, electronic displays, and the like. As it becomes possible, the importance of next-generation display devices that can process and implement them is increasing.

Such next-generation display devices should be able to realize light and small, high brightness, large screen, low power consumption, and low price, and one of them has recently attracted attention.

The liquid crystal display has superior display resolution than other flat panel display devices, and exhibits a response speed that is higher than that of a CRT when a moving image is realized.

The driving principle of the liquid crystal display device is to use optical anisotropy and polarization of the liquid crystal. Since the liquid crystal is thin and long in structure, the liquid crystal has directivity in the arrangement of molecules, and the direction of the molecular arrangement can be controlled by artificially applying an electric field to the liquid crystal.

Therefore, if the molecular arrangement direction of the liquid crystal is arbitrarily adjusted, the molecular arrangement of the liquid crystal is changed, and light is refracted in the molecular arrangement direction of the liquid crystal due to optical anisotropy to express image information.

Currently, an active matrix LCD (AM-LCD), in which a thin film transistor (TFT) and pixel electrodes connected to the thin film transistor are arranged in a matrix manner, is most noticeable because of its excellent resolution and video performance. I am getting it.

The structure of the liquid crystal panel, which is a basic component of the liquid crystal display, is as follows.

1 is a schematic plan view of a liquid crystal panel for a general liquid crystal display device.

As shown, the first and second substrates 110 and 130 in which the image display area I and the image non-display area II forming the periphery of the image display area I are defined are arranged to face each other. A seal pattern 140 for joining the first and second substrates 110 and 130 is formed at the boundary between the image display area I and the non-image display area II, and the liquid crystal layer 140 is formed in the seal pattern 140. Not shown).                         

The liquid crystal layer is injected through the liquid crystal injection hole 142 configured at one side of the seal pattern 140, and after injection, is prevented from leaking to the outside by the sealing seal.

Although not shown in detail, a plurality of gates and data wires (not shown) formed to cross each other are formed in the image display area III of the first substrate 110, and at a point where the gates and data wires cross. A thin film transistor is formed, and the pixel electrode is formed by being connected to the thin film transistor.

Although not shown in the drawing, the red, green, and blue color filters for coloring light of a specific wavelength band, and the light leakage phenomenon are disposed on the color boundaries and non-pixel areas of the color filter on the inner surface of the second substrate 130. Black matrix to prevent and a common electrode to which a common voltage is applied.

FIG. 2 is an enlarged view of a portion 'A' of FIG. 1 and is a plan view of an enlarged portion of a liquid crystal panel for a conventional liquid crystal display.

As shown in FIG. 2, the liquid crystal panel according to the present invention includes the first and second substrates 110, in which the image display area I and the image non-display area II forming the periphery of the image display area I are defined. 130 are disposed to face each other, and a seal pattern 140 for joining the first and second substrates 110 and 130 is formed at the boundary between the image display region I and the image non-display region II. The liquid crystal layer (not shown) is interposed in the seal pattern 140.

Here, an Ag dot 166 electrically connecting the first and second substrates 110 and 130 is formed in a part of the image non-display area II of the liquid crystal panel.

At this time, when the Vcom voltage is applied from the outside, a scan voltage is applied to the gate electrode of the thin film transistor of the first substrate 110 so that the thin film transistor is turned on and the Vcom voltage is applied from the outside. ) Is a common electrode (not shown) formed on the first substrate 110 and formed on the second substrate 130 in the common voltage wiring 112 through the dot pad 188 and the silver dot 166. Signal is applied.

Here, the silver dot 166 in the first substrate 110 is connected through the common voltage wiring 112 and a plurality of dot pad contact holes 189 formed in the image non-display area. The hole 189 is exposed to the air, and is easily exposed to moisture or foreign matter, and thus has a structure vulnerable to corrosion or corrosion.

In addition, the dot pad contact hole 189 may be formed in the image non-display area so that the common voltage line 112 may be directly exposed to the atmosphere when a crack occurs.

The present invention provides a liquid crystal display device and a manufacturing method thereof, which prevent the electrical or corrosion defects causing product defects by forming the silver dot pad contact holes for electrically connecting the first and second substrates through a silver dot in a liquid crystal panel under a seal pattern. The purpose is to provide a method.

In order to achieve the above object, the liquid crystal display device according to the present invention includes: first and second substrates that are disposed to face each other, and a liquid crystal layer is formed therebetween, common voltage wirings formed on the first substrate, and the second substrate. A common electrode, a seal pattern formed at an edge between the first and second substrates, and at least one silver dot electrically connecting the first and second substrates to the outside of the seal pattern. In the liquid crystal display, a plurality of silver dot pad contact holes are formed on the first substrate under the seal pattern.

And a silver dot pad connected to the silver dot on the first substrate and connected to the common voltage line through the silver dot pad contact hole.

A thin film transistor may be provided at the intersection of the gate line and the data line arranged vertically and horizontally on the first substrate to form a plurality of pixel regions.

In addition, in order to achieve the above object, a method of manufacturing a liquid crystal display device according to the present invention includes a gate wiring and a data wiring arranged vertically and horizontally so as to define an image display area on a first substrate and forming a plurality of pixel areas, and an intersection thereof. Forming a thin film transistor and a common voltage wiring to apply an external signal to the image non-display area; Forming an insulating film on a first substrate on which the thin film transistor is formed and forming a plurality of silver dot pad contact holes at a predetermined position to expose a common voltage wiring to the insulating film; Forming a pixel electrode electrically connected to the thin film transistor and a silver dot pad formed as the image non-display area on the silver dot pad contact hole; Forming a seal pattern on the silver dot pad contact hole along the periphery of the image display area; Forming a silver dot on the silver dot pad formed in the image non-display area; And bonding the first substrate and a second substrate having a common electrode in contact with the silver dot.                     

The pixel electrode and the silver dot pad may be made of a transparent conductive material.

The thin film transistor penetrates through a gate electrode formed on a substrate, a gate insulating film covering the gate electrode, an active layer formed on the gate insulating film, an interlayer insulating film formed on the active layer, and the active layer and an interlayer insulating film. And source and drain electrodes connected to and spaced apart from each other by a predetermined interval.

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

3 is a plan view schematically illustrating a part of a liquid crystal panel for a liquid crystal display according to the present invention, and FIG. 4 is a cross-sectional view showing the liquid crystal panel shown in FIG.

As shown in Figs. 3 and 4, the liquid crystal panel according to the present invention includes first and second substrates in which an image non-display area (IV) forming a peripheral portion of the image display area (III) and the image display area (III) is defined. 210 and 220 are arranged to face each other.

A seal pattern 260 is formed at the boundary between the image display area III and the image non-display area IV to bond the first and second substrates 110 and 120 to each other.

The liquid crystal layer 250 is interposed in the seal pattern 260, and the liquid crystal is disposed between the pixel electrode 281 of the first substrate 210 and the common electrode 243 of the second substrate 220. The molecular arrangement is injected into the substrate, and the molecular arrangement is changed by the voltage difference between the pixel electrode 281 and the common electrode 243. The liquid crystal display device is driven by the change in the molecular arrangement.

Here, an Ag dot 266 electrically connecting the first and second substrates 210 and 220 is formed in a part of the image non-display area IV of the liquid crystal panel.

The Vcom signal applied from the common voltage line 212 of the first substrate 210 is applied to the silver dot 266 through the dot pad 288, and the silver dot 266 of the second substrate 220 is applied. It is connected to the common electrode 243.

In this case, the first substrate 210 has a dot pad contact hole 289 formed through the passivation layer 270 and the gate insulating layer 230 to connect the dot pad 288 and the common voltage wiring 212. .

The dot pad contact hole 289 is formed under the seal pattern 260 to prevent corrosion and corrosion, and the dot pad contact hole 289 is prevented from being exposed to the outside by the seal pattern 260.

Referring to FIG. 4, a gate electrode 222 made of a conductive material such as a metal and a common voltage wiring 212 are formed on a transparent first substrate 210, and a silicon nitride film SiN _x or a silicon oxide film is formed thereon. The gate insulating film 230 made of SiO ₂ covers the gate electrode 222.

An active layer 241 made of amorphous silicon is formed on the gate insulating layer 230 on the gate electrode 222, and ohmic contact layers 251 and 252 made of amorphous silicon doped with impurities are formed thereon. .

Source and drain electrodes 261 and 262 made of a conductive material such as metal are formed on the ohmic contact layers 251 and 252, and the source and drain electrodes 261 and 262 are formed together with the gate electrode 222. The transistor T is formed.

Although not illustrated, the gate electrode 222 is connected to the gate wiring, the source electrode 261 is connected to the data wiring, and the gate wiring and the data wiring are orthogonal to each other to define the pixel region.

Subsequently, a passivation layer 270 made of a silicon nitride film, a silicon oxide film, or an organic insulating layer is formed on the source and drain electrodes 261 and 262, and the passivation layer 270 is a drain contact hole exposing the drain electrode 262. Has 271.

When the drain contact hole 271 is formed, a dot pad contact hole 289 is formed to expose the common voltage line 212 and penetrate the protective layer 270 and the gate insulating layer 230.

A pixel electrode 281 made of a transparent conductive material is formed in the pixel area above the passivation layer 270, and the pixel electrode 281 is connected to the drain electrode 262 through a contact hole 271.

In addition, the dot pad 288 is formed at a predetermined position of the image non-display area IV including the dot pad contact hole 289 made of a transparent conductive material constituting the pixel electrode 281.

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

On the other hand, the second substrate 220 is spaced apart from the first substrate 210 at a predetermined interval on the first substrate 210, and a transparent black substrate 220 is disposed on the inner surface of the second substrate 220. 221 is formed at a position corresponding to the thin film transistor T.

Although not shown, the black matrix 221 also covers portions other than the pixel electrode 281.

A color filter 231 is formed below the black matrix 221. The color filter 231 has a color of red, green, and blue sequentially repeated. It corresponds to this one pixel area.

A common electrode 243 made of a transparent conductive material is formed under the color filter 231.

The liquid crystal layer 250 is injected between the first and second substrates 210 and 220.

Meanwhile, a seal pattern 260 is formed between the first substrate 210 and the second substrate 220 to form a gap for injecting liquid crystal and prevent leakage of the injected liquid crystal.

In order to apply the common signal Vcom supplied from an external circuit on the second substrate 220 through the common voltage line 212, an Ag dot 266 is provided. 2 The substrates 210 and 220 are electrically connected.                     

Therefore, when the common voltage Vcom is applied from the outside, a scan voltage is applied to the gate electrode 222 of the thin film transistor T of the first substrate 210 to turn on the thin film transistor.

In this case, a signal voltage flows from the source electrode 261 of the thin film transistor to the drain electrode 262 so that the signal voltage is applied to the pixel electrode 281 connected to the drain electrode 262.

Then, the common electrode of the pixel electrode 281 of the second substrate 220 and the first substrate 210 may be caused by the difference between the common voltage applied to the common electrode 243 and the signal voltage of the pixel electrode 281. The liquid crystal display is driven by changing the arrangement of liquid crystal molecules in the liquid crystal layer 250 formed between the 243.

As mentioned above, the common voltage line 212 receiving the common voltage from the outside is positioned on the first substrate 210, and the common electrode 243 is located on the second substrate 220. The common electrode 243 is connected to the common voltage line 212 by an Ag dot 260 formed on the 212.

Therefore, a common voltage is applied to the common electrode 243 through the silver dot 266.

Hereinafter, a method of manufacturing the liquid crystal panel configured as described above will be described in detail.

First, a thin film transistor T is formed at an intersection thereof with a gate line and a data line arranged vertically and horizontally to define an image display area on the first substrate 210.

A common voltage wiring 212 for applying an external signal in the image non-display area is formed.

An insulating film is formed on the first substrate 210 on which the thin film transistor is formed, and a plurality of silver dot pad contact holes 289 exposing the common voltage line 212 are formed at a predetermined position.

In this case, the insulating layer includes a protective layer 270 made of a silicon nitride layer, a silicon oxide layer, or the like, and includes a gate insulating layer 230 formed on the gate electrode 222 when the thin film transistor is formed.

The pixel electrode 281 electrically connected to the thin film transistor and the silver dot pad 288 formed as the image non-display area are formed on the silver dot pad contact hole 289.

Subsequently, a seal pattern 260 is formed on the silver dot pad contact hole 289 along the periphery of the image display area.

Then, a silver dot 266 is formed on the silver dot pad 288 formed in the image non-display area, and finally, a common electrode contacting the first substrate 210 and the silver dot 266. The second substrate 220 on which the 243 is formed is bonded.

In this case, the pixel electrode 281 and the silver dot pad 288 are made of a transparent conductive material.

Although the present invention has been described in detail with reference to specific examples, this is for explaining the present invention in detail, and the liquid crystal display and the manufacturing method thereof according to the present invention are not limited thereto and within the technical spirit of the present invention. It is apparent that modifications and improvements are possible by those skilled in the art.

According to the present invention, the dot pad contact holes for electrically connecting the first and second substrates through the silver dots in the liquid crystal panel are formed under a seal pattern, thereby preventing electrical or corrosion failure, thereby improving product quality and reliability. .

Claims (6)

First and second substrates disposed to face each other and having a liquid crystal layer interposed therebetween, common voltage wiring formed on the first substrate, common electrodes formed on the second substrate, and formed at edges between the first and second substrates. In a liquid crystal display device including a seal pattern and at least one silver dot electrically connecting the first and second substrates outside the seal pattern, A plurality of silver dot pad contact holes are formed in the first substrate under the seal pattern, and the second substrate has a black matrix formed inside the seal pattern. The method of claim 1, And a silver dot pad connected to the silver dot on the first substrate and connected to a common voltage line through the silver dot pad contact hole. The method of claim 1, And a thin film transistor disposed at an intersection thereof with a gate line and a data line arranged vertically and horizontally on the first substrate to form a plurality of pixel regions. A gate line and data line arranged vertically and horizontally to define an image display area on the first substrate, and a thin film transistor at an intersection thereof, and an external signal applied to an image non-display area outside the image display area. Forming a common voltage wiring; Forming a plurality of silver dot pad contact holes for forming an insulating film on the first substrate on which the thin film transistor is formed and exposing a common voltage line to the insulating film; Forming a pixel electrode electrically connected to the thin film transistor and a silver dot pad formed as the image non-display area on the silver dot pad contact hole; Forming a seal pattern on the silver dot pad contact hole along the periphery of the image display area; Forming a silver dot on the silver dot pad formed in the image non-display area; Bonding the first substrate to a second substrate having a common electrode in contact with the silver dot; And a black matrix is formed on the second substrate to the inner side of the seal pattern. The method of claim 4, wherein And the pixel electrode and the silver dot pad are made of a transparent conductive material. The method of claim 4, wherein The thin film transistor penetrates through a gate electrode formed on a substrate, a gate insulating film covering the gate electrode, an active layer formed on the gate insulating film, an interlayer insulating film formed on the active layer, and the active layer and an interlayer insulating film. A method of manufacturing a liquid crystal display device comprising a source and a drain electrode connected to each other and spaced apart from each other by a predetermined interval.

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