KR101287205B1 - Liquid crystal display device and method for manufacturing the same - Google Patents

Abstract

The present invention relates to a liquid crystal display device and a method for manufacturing the same, which can improve the yield by removing the transparent conductive layer between the metal layer of the common wiring so that light is sufficiently transmitted to the photocurable sealing material, and is divided into an active region and a dummy region. First and second substrates facing each other; A common wiring including a plurality of metal layers in the dummy region of the first substrate and a transparent conductive layer stacked on the plurality of metal layers except between the metal layers; A photocurable sealing material formed on the common wiring layer between the first and second substrates to bond the first and second substrates together; And a liquid crystal layer formed between the first and second substrates bonded by the photocurable sealing material.

Photo-curable seal material, common wiring

Description

Liquid crystal display device and method for manufacturing the same

1 is an exploded perspective view showing a part of a general liquid crystal display device

2 is a layout view of a conventional liquid crystal display device;

3 is an enlarged plan view of the common wiring of FIG. 2;

4 is a cross-sectional view taken along line II ′ of FIG. 2.

5 is an enlarged plan view of a common wiring according to the present invention;

6 is a cross-sectional view of a common wiring of the liquid crystal display according to the present invention.

7A to 7D are cross sectional views of a liquid crystal display according to the present invention.

Description of the Related Art [0002]

200: metal wiring 201: metal layer

202: transparent conductive layer 211: gate electrode

212: gate insulating film 213: active layer

214: Derita lines 214a, 214b: source / drain electrodes

215: protective film 216: contact hole

217: pixel electrode 250: photocurable sealing material

251: conductive ball 300: lower substrate

400: upper substrate 401: black matrix layer

402: common electrode

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display (hereinafter referred to as "LCD"), and more particularly, to a liquid crystal display device suitable for improving the degree of curing of a photocurable sealing material and a manufacturing method thereof.

Due to the excellent image quality, light weight, thinness, and low power consumption, LCD is the most widely used to replace CRT (Cathode Ray Tube) as a mobile image display device. Various developments have been made for televisions to receive and display, monitors for computers, and the like.

The liquid crystal display device may be roughly divided into a liquid crystal panel for displaying an image and a driving part for applying a driving signal to the liquid crystal panel. The liquid crystal panel includes first and second glass substrates, And a liquid crystal layer injected between the first and second glass substrates.

The first glass substrate (TFT array substrate) may include a plurality of gate wirings arranged in one direction at a predetermined interval, a plurality of data wirings arranged at regular intervals in a direction perpendicular to the respective gate wirings, and A plurality of pixel electrodes formed in a matrix form in each pixel region defined by crossing each of the gate wirings and the data wirings and a plurality of pixels that are switched by signals of the gate wirings to transfer signals of the data wirings to the pixel electrodes. A thin film transistor is formed.

The second glass substrate (color filter substrate) is provided with a black matrix layer for shielding light in a portion excluding the pixel region, an R, G, and B color filter layers for expressing color hues, Respectively. Of course, the common electrode is formed on the first glass substrate in the transverse electric field type liquid crystal display device.

The first and second glass substrates are bonded by a sealing material having a predetermined space by a spacer and having a liquid crystal injection hole, and a liquid crystal is injected between the two substrates.

At this time, in the liquid crystal injection method, the liquid crystal is injected between the two substrates by the osmotic pressure phenomenon when the liquid crystal injection port is locked in the liquid crystal container by keeping the vacuum state between the two substrates bonded together by the reality. When the liquid crystal is injected in this manner, the liquid crystal injection hole is sealed with the sealing material.

On the other hand, as described above, the driving principle of the liquid crystal display device utilizes the optical anisotropy and the polarization property of the liquid crystal.

Since the liquid crystal has a long structure, it has a direction 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.

Accordingly, when the molecular arrangement direction of the liquid crystal is arbitrarily adjusted, the molecular arrangement of the liquid crystal is changed, and light polarized by optical anisotropy may be arbitrarily modulated to display image information.

These liquid crystals can be classified into a positive liquid crystal having a positive dielectric anisotropy (+) and a negative liquid crystal having a negative (-) according to a specific electrical classification. The liquid crystal molecules having a positive dielectric anisotropy have a long axis And the liquid crystal molecules in which the dielectric anisotropy is negative are aligned perpendicularly to the direction in which the electric field is applied and the long axis of the liquid crystal molecules.

1 is an exploded perspective view showing a part of a general TN liquid crystal display device.

As shown in FIG. 1, the lower substrate 1 and the upper substrate 2 bonded to each other with a predetermined space, and a liquid crystal layer 3 formed between the lower substrate 1 and the upper substrate 2 are formed. have.

More specifically, the lower substrate 1 has a plurality of gate lines 4 arranged in one direction at regular intervals to define the pixel region P, and in a direction perpendicular to the gate lines 4. A plurality of data lines 5 are arranged at regular intervals, and pixel electrodes 6 are formed in each pixel region P where the gate lines 4 and the data lines 5 intersect, and each of the gate lines The thin film transistor T, which is turned on / off according to the signal of the gate wiring and applies the signal of the data wiring 5 to each pixel electrode 6, is formed at the intersection between the data wiring 5 and the data wiring 5. Formed.

The upper substrate 2 includes a black matrix layer 7 for blocking light in a portion excluding the pixel region P, an R, G, and B color filter layers 8 for expressing color hues, The common electrode 9 is formed.

Since the common electrode 9 is formed on the upper substrate 2 as described above, in order to apply the common voltage to the common electrode 9, common wiring is formed in the dummy region of the lower substrate 1, and the common wiring and the common electrode ( Ag dots for electrically connecting 9) are formed between the upper and lower substrates. This will be described in detail as follows.

2 is a schematic plan view of a conventional liquid crystal display, FIG. 3 is an enlarged plan view of a portion A of FIG. 2, and FIG. 4 is a cross-sectional view taken along line II ′ of FIG. 2.

As shown in FIG. 2, the lower substrate 1 and the upper substrate 2 are bonded to each other with a predetermined space. The lower substrate 1 is divided into a display area and a non-display area, and is bonded to the upper substrate 2 in the display area.

As described above, the display areas of the bonded upper and lower substrates 1 and 2 are divided into an active area A / A and a dummy area D.

In the active region of the lower substrate 1, as illustrated in FIG. 1, a gate wiring 4, a data wiring 5, a pixel electrode 6, and a thin film transistor T are formed.

As shown in FIG. 2, a common wiring 100 is formed in a dummy area of the display area of the lower substrate 1, and a gate driving IC 101 and a data driving IC 102 and the above are formed in a non-display area. Leading lines 103 and 104 are formed for connecting each gate wiring 4 and data wiring 5.

As shown in FIG. 1, the black matrix layer 7, the R, G, and B color filter layers 8 and the common electrode 9 are formed in the active region of the upper substrate 2, and the dummy region is black. A matrix 7 layer is formed.

The seal member 105 is formed in the dummy region (near the edge of the upper substrate) between the upper and lower substrates 1 and 2 formed as described above to bond the upper and lower substrates, and the liquid crystal layer 3 is formed between the two substrates. do.

Here, the sealant 105 is a photocurable sealant.

3 and 4, the common wiring 100 includes a metal layer 108 such as the gate wiring 4 or a data wiring 5 and a pixel electrode 6 on the metal layer 108. The common wiring 100 is formed by stacking a transparent conductive layer 109 such as ITO, which is the same material as the (). In this case, the transparent conductive layer 109 is formed wider than the metal layers 108 to increase the contact area with the common electrode.

Since the sealing material 105 overlaps the common wiring 100, in order to cure the sealing material 105 by irradiating light to the sealing material 105 after the substrate is bonded, the common wiring 100 may be used. The plurality of metal layers 108 may be formed to have a predetermined interval 107 so as to form a passage through which the light is irradiated onto the common wiring 100 without forming the metal layer 108 through a tube.

In general, Ag dots are separately formed in order to electrically connect the common wiring 100 formed on the lower substrate 1 and the common electrode 9 formed on the upper substrate 2. The two substrates were bonded together using the sealing material 105 including the balls 106. Therefore, the common wiring 100 formed on the lower substrate 1 and the common electrode 9 formed on the upper substrate 2 are electrically connected by the conductive balls 106.

However, such a conventional liquid crystal display device has the following problems.

That is, although a path through which light is irradiated is formed on the metal layer of the metal wiring in order to irradiate light on the sealing material, since the transparent conductive layer 109 is formed thereon, when irradiating light to cure the sealing material. Since a transparent conductive layer such as ITO formed on the metal layer absorbs light having a short wavelength, light is not sufficiently transmitted to the sealing material and the sealing material is not sufficiently cured, thereby causing a defect.

The present invention has been made to solve the above problems, and a liquid crystal display device and a method for manufacturing the same, which can improve the yield by removing the transparent conductive layer between the metal layer of the common wiring so that light is sufficiently transmitted to the photo-curable sealing material. The purpose is to provide.

According to an aspect of the present invention, there is provided a liquid crystal display including: first and second substrates which are divided into an active region and a dummy region and face each other; A common wiring including a plurality of metal layers in the dummy region of the first substrate and a transparent conductive layer stacked on the plurality of metal layers except between the metal layers; A photocurable sealing material formed on the common wiring layer between the first and second substrates to bond the first and second substrates together; And a liquid crystal layer formed between the first and second substrates bonded by the photocurable sealing material.

In addition, in the method of manufacturing the liquid crystal display device according to the present invention for achieving the above object, a plurality of common wiring metal layers are formed in the dummy region of the first substrate divided into the active region and the dummy region, Forming a gate line and a gate electrode; Forming a gate insulating film on an entire surface of the first substrate including the metal layer and the gate line; Forming an active layer on the gate insulating film above the gate electrode of the active region; Forming source / drain electrodes on both sides of the active layer in the active region; Depositing a passivation layer on the entire surface of the substrate, forming a contact hole by removing the passivation layer on the drain electrode, and exposing the plurality of metal layers by removing the gate insulating layer and the passivation layer in the dummy region; And forming a pixel electrode in the pixel region of the active region so as to be connected to the drain electrode through the contact hole, and forming a transparent conductive layer on the metal layer of the dummy region.

In addition, a method of manufacturing a liquid crystal display according to the present invention for achieving the above object comprises the steps of forming a gate line and a gate electrode in an active region of the first substrate divided into an active region and a dummy region; Forming a gate insulating film on an entire surface of the first substrate including the gate line; Forming an active layer on the gate insulating film above the gate electrode of the active region; Forming a source / drain electrode on both sides of the active layer of the active region and simultaneously forming a plurality of common wiring metal layers on the gate insulating layer of the dummy region; Depositing a passivation layer on the entire surface of the substrate and removing the passivation layer on the drain electrode and the dummy region; In addition, a pixel electrode is formed in the pixel region of the active region to be connected to the drain electrode, and a transparent conductive layer is formed on the metal layer of the dummy region.

A liquid crystal display and a manufacturing method thereof according to the present invention having such a feature will be described in detail with reference to the accompanying drawings.

5 is a plan view of the common wiring of the liquid crystal display according to the present invention, and FIG. 6 is a cross-sectional view of the common wiring of the liquid crystal display according to the present invention.

As mentioned in FIG. 2, the bonded upper and lower substrates are divided into a display area and a non-display area, and the display area is divided into an active area A / A and a dummy area D. FIG.

The active area and the non-display area of the display area are the same as mentioned in the related art.

Therefore, in the present invention, the structure of the dummy area in the display area will be described. That is, the common wiring 200 is formed on the lower substrate of the dummy region.

Here, as shown in FIG. 5, the common wiring 200 includes a plurality of metal layers 201 and a plurality of metal layers 201 that are formed at a predetermined interval with a material such as the gate wirings or data wirings. The common wiring 200 is formed by stacking transparent conductive layers 202 such as ITO, which is the same material as the pixel electrode. In this case, the transparent conductive layer 202 is formed only on the plurality of metal layers 201, and is not formed between the metal layers 201.

The structure of the liquid crystal display according to the present invention in which the lower substrate and the upper substrate including the metal wiring 200 having the above structure are bonded together is shown in FIG. 6.

That is, as described with reference to FIG. 5, a common wiring 200 in which the plurality of metal layers 201 and the transparent conductive layer 202 are stacked is formed in the dummy region of the lower substrate 300.

In addition, a black matrix layer 401 and a common electrode 402 are formed in the dummy region of the upper substrate 400.

A photocurable sealing material 250 for bonding the two substrates between the lower substrate 300 formed as described above and the upper substrate 400 is formed. The sealing material 250 includes a conductive ball 251 for electrically connecting the metal wire 200 formed on the lower substrate 300 and the common electrode 402 formed on the upper substrate 400.

In this case, the sealing member 250 is formed to overlap the common wiring 200.

As described above, even when the sealing material 250 is formed to overlap the common wiring 200, the transparent conductive layer 202 constituting the common wiring 200 is not formed between the metal layers 201, so that the transparent conductive therebetween. Since the rate at which the layer 202 absorbs light having a short wavelength is reduced, the curing property of the sealing material 250 may be improved.

Referring to the manufacturing method of the liquid crystal display according to the present invention having such a structure as follows.

7A to 7D are cross-sectional views illustrating processes of the lower substrate of the liquid crystal display according to the present invention.

As shown in FIG. 7A, a low-resistance metal layer is deposited on the lower substrate 300 defined as the dummy region and the active region, and the metal layer is selectively removed by a photolithography process. ) And a gate electrode of a thin film transistor is formed in the active region.

A gate insulating film 212 is formed on the entire surface of the substrate including the metal layer 201 and the gate electrode 211.

As shown in FIG. 7B, a semiconductor layer is deposited on the gate insulating layer 212 and selectively removed to form an active layer 213 of a thin film transistor on the gate insulating layer above the gate electrode of the active region.

As shown in FIG. 7C, a low resistance metal layer is deposited on the entire surface of the substrate including the active layer and selectively etched to form source / drain electrodes 214a 214b and data lines 214 of the thin film transistor.

A protective film 215 is formed on the entire substrate including the data line.

As shown in FIG. 7D, the protective layer is selectively removed to form a contact hole 216 on the drain electrode 214b, and the protective layer 215 and the gate insulating layer 212 in the dummy region are formed. It removes and exposes the common wiring metal layer 201.

In addition, a transparent conductive film such as ITO or IZO is deposited on the entire surface of the substrate and selectively removed to form a pixel electrode 217 in the pixel region to be connected to the drain electrode 214b through the contact hole 216. A common conductive transparent layer 202 is formed on the metal layer 201 in the dummy region.

In this case, the common wiring transparent conductive layer 202 is not formed between the metal layers 201 and is formed to surround the metal layer 201 on the metal layer 201.

Thereafter, although not shown in the drawings, a sealing material having conductive balls is applied to the lower substrate or the upper substrate of the dummy region, and the upper and lower substrates are bonded to each other, and then the sealing material is irradiated with light to cure the sealing material. (See FIG. 6).

The common wiring metal layer 201 is formed of the same material as the gate electrode 211, but is not limited thereto and may be formed of the same material as the data line 214.

As described above, the liquid crystal display and the manufacturing method thereof according to the present invention have the following effects.

That is, since the transparent conductive layer is formed only on the metal layer for common wiring formed in the dummy region, the yield can be improved by increasing the light transmission efficiency to the photocurable sealing material.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and it is common in the art that various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be evident to those who have knowledge of.

Claims (7)

First and second substrates divided into an active region and a dummy region and facing each other; It is formed in the dummy region of the first substrate to supply a common voltage to the common electrode formed on the second substrate, and is in direct contact with each metal layer on the plurality of metal layers except between the plurality of metal layers and the respective metal layers A common wiring composed of a transparent conductive layer laminated to surround each metal layer; A photocurable sealing material formed along the common wiring between the first and second substrates to bond the first and second substrates together; And And a liquid crystal layer formed between the first and second substrates bonded by the photocurable sealing material. The method of claim 1, A thin film transistor array having a gate line, a data line, and a pixel electrode arranged in a direction perpendicular to each other is formed in an active region of the first substrate, the metal layer is formed of the same material as the gate line, and the transparent conductive layer The liquid crystal display device is formed of the same material as the pixel electrode. The method of claim 1, A thin film transistor array having gate lines, data lines, and pixel electrodes arranged in a direction perpendicular to each other is formed in an active region of the first substrate, and the metal layer is formed of the same material as the data line, and the transparent conductive layer The liquid crystal display device is formed of the same material as the pixel electrode. Forming a plurality of common wiring metal layers for supplying a common voltage to a dummy region of the first substrate, which is divided into an active region and a dummy region, and forming a gate line and a gate electrode in the active region; Forming a gate insulating film on an entire surface of the first substrate including the metal layer and the gate line; Forming an active layer on the gate insulating film above the gate electrode of the active region; Forming source / drain electrodes on both sides of the active layer in the active region; Depositing a passivation layer on the entire surface of the first substrate, forming a contact hole by removing the passivation layer on the drain electrode, and exposing the plurality of metal layers by removing the gate insulating layer and the passivation layer in the dummy region; And A pixel electrode is formed in the pixel region of the active region to be connected to the drain electrode through the contact hole, and directly contacts each metal layer on the plurality of metal layers except between the metal layers of the dummy region and surrounds each metal layer Forming a transparent conductive layer so as to form a transparent conductive layer. delete Forming a gate line and a gate electrode in an active region of the first substrate divided into an active region and a dummy region; Forming a gate insulating film on an entire surface of the first substrate including the gate line; Forming an active layer on the gate insulating film above the gate electrode of the active region; Forming a plurality of common wiring metal layers for supplying a common voltage on the gate insulating layer of the dummy region while forming a source / drain electrode on both sides of the active layer of the active region; Depositing a passivation layer on the entire surface of the substrate and removing the passivation layer on the drain electrode and the dummy region; And A pixel electrode is formed in the pixel region of the active region to be connected to the drain electrode, and a transparent conductive layer is formed on the plurality of metal layers except for each metal layer of the dummy region to directly contact each metal layer and surround each metal layer. Method for manufacturing a liquid crystal display device comprising the step of forming. delete

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