KR101033459B1 - LCD with color-filter on TFT and method of fabricating of the same - Google Patents

Abstract

The present invention relates to a liquid crystal display device, and a liquid crystal display device having a COT structure in which a color filter is formed on an array substrate.

According to an exemplary embodiment of the present invention, a liquid crystal display device includes a patterned spacer formed on an upper substrate bonded to a lower substrate on which a color filter is formed, and a bonding key and a light leakage preventing pattern configured to correspond to an outer portion of the liquid crystal panel. It is characterized by producing in the step.

In this way, the process can be simplified, thereby reducing costs and time, thereby improving production yield and increasing product competitiveness.

Description

CIO structure liquid crystal display and manufacturing method thereof {LCD with color-filter on TFT and method of fabricating of the same}             

1 is an exploded perspective view schematically illustrating a configuration of a general liquid crystal display device;

2 is a cross-sectional view taken along the line II-II of FIG. 1,

3 is an enlarged cross-sectional view schematically illustrating a liquid crystal display device having a COT structure according to the related art.

4 is an enlarged cross-sectional view schematically showing a liquid crystal display device having a COT structure according to the present invention;

5A to 5C are cross-sectional views illustrating a method of manufacturing an upper substrate for a COT structure liquid crystal display device according to the present invention in a process sequence;

6 is an enlarged plan view schematically showing a part of an array substrate for a liquid crystal display device having a COT structure;

7 and 8 and 9 are cross-sectional views taken along the line VIII-VIII, VIII-VIII, VIII-VIII in Fig. 6,

10 is a plan view schematically showing the configuration of the light leakage prevention pattern and wiring according to the present invention;

11 is an enlarged cross-sectional view showing the configuration of a COT structure liquid crystal display device according to a second embodiment of the present invention;

12 is an enlarged cross-sectional view showing a part of an upper substrate constituting a COT structure liquid crystal display device according to a third embodiment of the present invention;

13A to 13C are cross-sectional views illustrating a method of manufacturing a top substrate for a COT structure liquid crystal display device according to a process sequence.

<Brief description of the main parts of the drawing>

200: first substrate 202: gate electrode

204: gate wiring 206: gate pad

208 gate insulating film 210 active layer

212 source electrode 214 drain electrode

216: protective film 218a, 218b: color filter

220: black matrix 222: planarization film

224: pixel electrode 226: gate pad electrode

250: second substrate 252c: spacer

254a: Locking key 254b: Light leakage prevention pattern

       256: common electrode 270: polarizing film

       280: top case

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a configuration of a liquid crystal display device including a thin film transistor array substrate having a color filter on TFT (COT) structure and a manufacturing method thereof.

In general, a liquid crystal display device displays an image by using optical anisotropy and birefringence characteristics of liquid crystal molecules. When an electric field is applied, the alignment of liquid crystals is changed, and the characteristics of light transmission vary according to the arrangement direction of the changed liquid crystals.

In general, a liquid crystal display device is formed by arranging two substrates on which electric field generating electrodes are formed 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 a 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.

1 is a view schematically showing a liquid crystal display according to the related art.

As shown, a typical color liquid crystal display 11 is a color filter (7) and said color filter comprising a black matrix (6) is configured between the sub color filter (8) and each of the sub color filter 8 (7 The upper substrate 5 having the common electrode 18 deposited thereon and the pixel region P are defined, and the pixel electrode 17 and the switching element T are formed in the pixel region, and the pixel region P The liquid crystal 14 is filled between the lower substrate 22 and the upper substrate 5 and the lower substrate 22 on which array wiring is formed.

The lower substrate 22 is also referred to as an array substrate, and the thin film transistor T, which is a switching element, is positioned in a matrix type, and the gate wiring 13 crosses the plurality of thin film transistors TFT. ) And data wirings 15 are formed.

In this case, the pixel area P is an area defined by the gate line 13 and the data line 15 crossing each other, and a transparent pixel electrode 17 is formed on the pixel area P as described above.

The pixel electrode 17 uses a transparent conductive metal having a relatively high transmittance of light, such as indium-tin-oxide (ITO).

A storage capacitor C connected in parallel with the pixel electrode 17 is formed on the gate wiring 13, and a part of the gate wiring 13 is used as the first electrode of the storage capacitor C, and a second As an electrode, an island-shaped source / drain metal layer 30 formed of the same material as the source and drain electrodes is used.

In this case, the source / drain metal layer 30 may be in contact with the pixel electrode 17 to receive a signal of the pixel electrode.

Although not shown, the liquid crystal panel configured as described above is provided with a scribing process of exposing gate pads and data pads respectively formed at one ends of the gate line and the data line, and bonding the exposed pads to the PCB. After the process is performed, the process is fixed to the backlight (back light) by using a top case (bottom case) and a bottom case (bottom case).

In this case, the top case fixing the liquid crystal panel functions to cover the periphery of the liquid crystal panel, but does not completely cover the periphery of the liquid crystal panel except for the image area.

To this end, conventionally, a light leakage preventing pattern is further configured as a periphery of the liquid crystal panel.

This will be described below with reference to FIG. 2.

2 is an enlarged cross-sectional view illustrating a periphery of a liquid crystal display according to the related art.

2 is a cross-sectional view through a process of cutting a portion of the upper substrate to expose the pad portion mentioned above.

As illustrated, the liquid crystal display device D includes a first substrate (lower substrate 40) and a second substrate (upper substrate 70) bonded to each other. Although not illustrated, the first and second substrates 40 and 70 may be bonded together. There is a liquid crystal layer (not shown) therebetween.

The polarizing film 80 is formed on the liquid crystal display device D, and the liquid crystal display device D is fixed through the top case TC.

One surface of the first substrate 40 includes a thin film transistor T and an array wiring (not shown). The thin film transistor T includes a gate electrode 42, an active layer 50, a source and a drain electrode 58. , 60).

Although not shown, a data line (not shown) connected to the source electrodes 58 and 60 of the thin film transistor T extends in one direction of the substrate and is connected to the gate electrode 42. 44 extends in a direction perpendicular to the data line (not shown) and defines a pixel region P with the data line (not shown).

In the pixel region P, a pixel electrode 64 transparent to the drain electrode 60 is formed.

In addition, a data pad electrode (not shown) and a gate pad electrode 46 are formed at one end of the data line (not shown) and the gate line 44, respectively, and the data pad electrode and the gate pad electrode (not shown). ) Is configured to contact the transparent data pad terminal electrode and the gate pad terminal electrode 66 (not shown).

The gate pad terminal electrode 66 and the data pad terminal electrode (not shown) are exposed to the outside and are subsequently connected to a PCB (not shown).

As described above, the first substrate 40 formed with the thin film transistor array wiring and the second substrate 70 bonded to each other through the sealant 84 are disposed in regions removed to expose the data pad terminal electrode and the gate pad terminal electrode. A bonding key K is formed, and a light leakage prevention pattern is formed to correspond to a region that the top case TC does not completely cover, and a region corresponding to the thin film transistor T of the lower substrate 40 is formed. The columnar spacer 82 is formed.

Referring to the cross-sectional structure, the bonding key is formed on the second substrate 70 by the first mask process, and at the same time, the light leakage preventing pattern 74 is formed on the periphery of the liquid crystal panel, and the thin film transistor T and the gate are formed. And a black matrix 72 corresponding to the data line 44 (not shown).

Next, a color filter 76 is formed on the surface of the second substrate 70 corresponding to the pixel area P of the first substrate 40 by a second mask process, and the color filters and the black matrix 72 and 74 are formed. The common electrode 78 is formed on the entire surface of the substrate 100 on which the substrate 100 is formed.

Next, in a third mask process, a transparent organic material is coated and patterned on the entire surface of the substrate 70 on which the common electrode 78 is formed, and the columnar spacers 82 are formed at portions corresponding to the thin film transistors T. ).

As described above, the liquid crystal display device D having the color filter 76 formed on the upper substrate 70 may be manufactured.

However, when the liquid crystal panel is manufactured by bonding the upper color filter substrate and the lower array substrate to each other as described above, the probability of light leakage due to the bonding error between the color filter substrate and the array substrate is very high.

Therefore, in order to solve this problem, a COT (color filter on TFT) structure for constructing a color filter on an array substrate has recently been proposed.

3 is an enlarged cross-sectional view schematically illustrating a configuration of a liquid crystal display device having a COT structure according to the related art.

As shown in the drawing, the liquid crystal display device 100 having the COT structure according to the related art is composed of an array substrate 110 and an upper substrate 150 which is bonded to the array substrate 110 through a sealant 180.

The array substrate 110 includes a thin film transistor T including a gate electrode 112, an active layer 120, a source electrode 122, and a drain electrode 124 on a substrate surface, but is not illustrated. A gate line and a data line 114 (not shown) are formed to vertically cross the transistor T to define the pixel area P. Referring to FIG.

A gate pad 116 is configured at one end of the gate wiring 114, and a data pad (not shown) is configured at one end of the data wiring (not shown).

Red, green, and blue color filters 128a, 128b (not shown) and a black matrix 130 are formed on the front surface of the substrate 110 having the thin film transistor T and the array wiring, and the color filters 128a and 128b. ) Is configured to correspond to the pixel region P, and the black matrix 130 is configured to correspond to the channel region of the thin film transistor T.

The transparent pixel electrode 134 in contact with the drain electrode 124 is formed on the color filters 128a, 128b, and 128c.

A common electrode 156 is formed on one surface of the upper substrate 150 corresponding to the array substrate 110 configured as described above, and separate light leakage corresponding to the outside of the liquid crystal panel including the sealant 180. The prevention pattern 152 is comprised.

In addition, a columnar spacer 158 is formed in a region corresponding to the thin film transistor T, and an alignment key corresponds to the upper substrate 150 of a portion cut out corresponding to the gate pad and data pad regions. key 154 is configured.

The bonding key 154 is used to bond the upper substrate 150 and the array substrate 110, and may be configured simultaneously with the black matrix 130.

A polarizer 170 is formed on the upper substrate 150, and a top case 160 covering a side surface of the liquid crystal panel is configured around the liquid crystal panel.

In the above-described configuration, the light leakage preventing pattern 152 is configured to shield the light shielding area corresponding to the non-shielding area by the top case 160 as described above in the general configuration of the liquid crystal display device.

However, in the general liquid crystal display device, since the color filter and the black matrix are formed on the upper substrate 150, the light leakage preventing pattern 152 is bonded to the black matrix in the process of forming the black matrix. The key 154 could be formed at the same time.

However, in the COT structure, since the color filters 128a, 128b, 128c and the black matrix 130 are formed on the array substrate 110, the bonding key 154 and the light leakage preventing pattern 152 should be separately configured. In addition, a mask process is added in addition to the process of forming the columnar spacers 158.

Therefore, the above-described conventional COT structure liquid crystal display device has a problem in that the production efficiency is very low due to an increase in cost and process time due to process addition.

The present invention has been proposed for the purpose of solving the above problems,

According to the present invention, in forming an upper substrate formed in a COT structure liquid crystal display device, a light leakage preventing pattern and a columnar spacer formed in correspondence to a periphery of a liquid crystal panel and a bonding key formed on the upper substrate are formed in one mask process. Characterized in that.

In this way, the production yield can be improved due to reduced manufacturing costs and reduced process time, and there is an advantage of improving the competitiveness of the product.

According to the present invention for achieving the above object, a C. O. (COT) structure liquid crystal display device is defined as a display area and a non-display area, the first substrate and the second substrate bonded through a sealant (adhesive means), and; Gate wirings and data wirings disposed on one surface of the first substrate and vertically intersecting with each other to define pixel regions; A switching element positioned at an intersection point of the gate line and the data line; A color filter configured in the pixel region; A transparent pixel electrode positioned on the color filter and connected to the switching element; A bonding key formed on a non-display area of the second substrate facing the first substrate, a first pattern stacked thereon, a light leakage preventing pattern and a second pattern stacked thereon, and the bonding key formed on the display area An opaque pattern made of the same material as the prevention pattern, and a columnar spacer stacked on the opaque pattern and formed of the same material as the first and second patterns; And a top case covering a periphery of the bonded first and second substrates.

The light leakage preventing pattern and the second pattern stacked thereon may be extended to the upper portion of the sealant, and the stacked light leakage preventing pattern and the second pattern may correspond to a plurality of gate wirings and data wirings formed on the lower substrate. It can be configured corresponding to each spaced area of the.

The second pattern may be configured to have a height lower than that of the first pattern and the columnar spacer.

A black matrix, which is a light shielding means, is further formed on the switching element, and the color filter is formed such that red, green, and blue color filters correspond to the pixel area, respectively.

The switching element is a thin film transistor including a gate electrode, an active layer, a source electrode and a drain electrode.

And a transparent common electrode formed between the second substrate, the bonding key, the light leakage preventing pattern, and the opaque pattern, wherein the common electrode and the pixel electrode are indium tin oxide (ITO) and indium zinc oxide (IZO). Consists of selected one of the transparent conductive metal group comprising a.

The first pattern, the second pattern, and the columnar spacer may be formed of a transparent organic material having photosensitive characteristics.

According to an aspect of the present invention, there is provided a method of manufacturing a COT structure liquid crystal display device, comprising: defining a first substrate and a second substrate as a display area and a non-display area; A gate line and a data line intersecting the one surface of the first substrate perpendicularly to each other to define a pixel area; forming a switching element positioned at an intersection point of the gate line and the data line; a color filter in the pixel area; Forming a; Forming a transparent pixel electrode connected to the switching element on the color filter; Defining a bonding key region and a light leakage preventing region in the non-display region of the second substrate and defining a spacer region in the display region; Stacking an opaque metal layer and a transparent organic layer on one surface of the second substrate; Patterning the organic layer by a mask process to form a first pattern in the bonding key region, a second pattern in the light leakage preventing region, and a columnar spacer in the spacer region; Removing the opaque metal layer exposed between the first pattern, the second pattern, and the spacer to form a bonding key on the lower portion of the first pattern and a light leakage prevention pattern on the lower portion of the second pattern; Contacting the first substrate and the second substrate through a sealant (adhesive means).

The light leakage preventing pattern and the second pattern stacked thereon may extend to an upper portion of the sealant.

The light leakage preventing pattern and the second pattern stacked thereon may correspond to a plurality of gate lines and data lines separated from each other in the lower substrate.

The second pattern may be formed at a height lower than that of the first pattern and the columnar spacer. The method may include a non-display area including a bonding key area and a light leakage prevention area on the substrate; Defining a display area including a spacer area; Stacking an opaque metal layer and a transparent organic layer on one surface of the substrate on which the non-display area and the display area are defined; Placing a mask including a reflection portion corresponding to a bonding key region and a spacer region, a transflective portion corresponding to the light leakage preventing region, and a transmission portion on the transparent organic layer; The organic layer is patterned by a mask process to form a first pattern in the bonding key region, a columnar spacer in the spacer region, and a second pattern having a height lower than that of the first pattern and the columnar spacer in the light leakage preventing region. Forming a; And removing an opaque metal layer exposed between the first pattern, the second pattern, and the spacer to form a bonding key at the bottom of the first pattern and a light leakage prevention pattern at the bottom of the second pattern.

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

Example

4 is a cross-sectional view schematically showing the configuration of a COT structure liquid crystal display device according to the present invention.

As illustrated, the COT structure liquid crystal display device 198 according to the present invention includes a liquid crystal panel in which a lower substrate 200, an array substrate, and an upper substrate 250 are bonded to each other through a sealant 260. And a top case 280 for fixing the liquid crystal panel LP and the polarizing plate 270 from the side thereof.

The liquid crystal panel LP is divided into a display area DA where an image is actually displayed and a non-display area NDA surrounding the display area.

The display area DA is composed of hundreds of thousands to millions of pixels P depending on the size and resolution of the liquid crystal panel LP.

In the lower substrate, a gate line 204 is formed in one direction for each pixel P, and a data line (not shown) is formed in a direction perpendicular thereto, and the gate line 204 and the data line (not shown) are formed. The thin film transistor T is formed at each crossing portion, and the thin film transistor T includes a gate electrode 202, an active layer 210, a source electrode 212, and a drain electrode 214.

A gate pad 206 is formed at the end of the gate line 204, and a data pad (not shown) is formed at the end of the data line (not shown).

Red, green, and blue color filters 128a, 128b, and 128c are formed for each pixel P, and a black matrix 220 is formed corresponding to the thin film transistor T.

The upper portion of the color filters 128a and 128b may be independently patterned for each pixel P to form the pixel electrode 224, and the pixel electrode 224 may be in contact with the drain electrode 214 so that the drain electrode ( The pixel voltage is inputted from 214.

The upper substrate 250 corresponding to the lower substrate 200 configured as described above has a common electrode CL and a surface corresponding to the data pad and the gate pad 206 on the common electrode teeth. An area corresponding to the periphery of the liquid crystal panel LP including the sealant 260, an alignment key 254a, and an area corresponding to the thin film transistor T The columnar spacer 252c is formed in the inside.

In the above-described configuration, the characteristic is to fabricate the bonding key 254a, the light leakage preventing pattern 254b, and the columnar spacer 252c in one mask process.

Hereinafter, a method of forming an upper substrate of a COT structure liquid crystal display device according to the present invention will be described with reference to FIGS. 5A to 5C.

First, as shown in FIG. 5A, indium tin oxide (ITO) and indium zinc oxide (IZO) are formed on a transparent insulating substrate 250 defined as a display area DA and a non-display area NDA. The common electrode CL is formed by depositing one selected from the group of transparent conductive metals including the ().

Next, an opaque metal layer M is formed by depositing chromium oxide (CrO _x ) having a low light reflectance on the common electrode CL, and subsequently applying a transparent photosensitive organic material to the photosensitive layer (positive characteristic) ( Form O).

In this case, the non-display area NDA is divided into the bonding key area AK and the area LSPA in which the light leakage prevention pattern is to be formed, and the area LSPA in which the light leakage prevention pattern is to be formed is formed around the substrate 250. Is defined throughout.

Next, after placing the mask 300 composed of the transmission portion (T) and the blocking portion (S) on the upper portion of the photosensitive layer (O) and successively, by irradiating light to the upper portion of the mask 300, the lower photosensitive layer The process of exposing and developing (O) is performed.

As shown in FIG. 5B, when the exposure process and the development process are performed, the first pattern 252a and the second pattern correspond to the bonding key area AK and the light leakage preventing pattern area LSPA in the non-display area NDA. 252b is formed, and the columnar spacer 252c is formed in the display area DA at the same height.

Next, a process of wet etching the lower opaque metal layer exposed between the first pattern 252a, the second pattern 252b, and the spacer 252c is performed.

As shown in FIG. 5C, when the wet etching process is performed, an opaque metal remains only under the respective patterns.

Accordingly, the bonding key region AK has a shape in which the bonding key 254a and the transparent first pattern 252a are stacked, and the light leakage preventing pattern region LSPA also has a light leakage preventing pattern 254b and a transparent second pattern. 252b is configured, and in the display area DA, an opaque metal third pattern 254c and a columnar spacer 252c are formed.

At this time, the columnar spacer 252c is preferably configured randomly.

As described above, the bonding key 254a, the light leakage preventing pattern 254b, and the columnar spacer 252c may be formed on the substrate 250.

The planar configuration of the lower substrate 210 to be bonded to the upper substrate 250 formed as described above will be briefly described below.

delete

6 is a plan view schematically illustrating a configuration of an array substrate for a COT liquid crystal display device according to a first embodiment of the present invention.

As illustrated, the array substrate 200 is divided into a display area DA and a non-display area NDA.

A gate line 204 is formed on the substrate 200 including the display area DA and the non-display area NDA and includes a gate pad 206 at one end thereof. A data line DL that intersects 204 vertically and includes a data pad DP at one end is formed.

The thin film transistor T including the gate electrode 202, the active layer 210, the source electrode 212, and the drain electrode 214 is formed at the intersection of the two wirings 204 and DL.

The color filters 218a and 218b of red, green, and blue are sequentially configured to correspond to the plurality of pixel regions P, and the black matrix BM is formed to correspond to the thin film transistor T.

An upper portion of the color filters 218a and 218b forms a transparent pixel electrode 224 in contact with the drain electrode 214.

In the above-described configuration, by forming an island-shaped metal electrode CM on a part of the gate wiring 204 and connecting the pixel electrode with the metal electrode CM, a part of the gate wiring is used as the first electrode. The storage capacitor C _ST may be configured using the metal electrode CM as an electrode.

7, 8, and 9, a method of manufacturing an array substrate for a liquid crystal display device having a COT structure configured as described above will be described.

7, 8, and 9 are cross-sectional views taken along line VIII-VIII, VIII-VIII, and VIII-VIII in Fig. 6.

As shown in the drawing, a gate line 204 extending in one direction and including a gate pad 206 at one end and a gate electrode 202 protruding from the gate line 204 are formed on the substrate 200. .

Next, an inorganic insulating material group including silicon nitride (SiN _x ) and silicon oxide (SiO ₂ ) on the entire surface of the substrate 200 on which the gate pad 206, the gate wiring 204, and the gate electrode 202 are formed. One or more selected materials are deposited to form the gate insulating layer 208.

Next, an island-like active layer 210 and an ohmic contact layer OCL are sequentially stacked on the gate insulating layer 208 corresponding to the gate electrode 202.

Next, a conductive metal layer is deposited and patterned on the entire surface of the substrate 200 on which the ohmic contact layer OCL is formed. The source electrode 212 and the drain electrode are in contact with the ohmic contact layer OCL and are spaced apart from each other. And a data line (not shown) connected to the source electrode 212 and vertically intersecting with the gate line 204 to define the pixel area P, and including a data pad DP at one end thereof. To form. Next, a thin film transistor T including the gate electrode 202, the active layer and the ohmic contact layer 210 (OCL), the source electrode 212, and the drain electrode 214 is formed on the entire surface of the substrate 200. The protective film 216 is formed by depositing one selected from the group of inorganic insulating materials described above.

Next, the black matrix 220 is formed corresponding to the thin film transistor T, the gate lines, and the data lines 204 and DL.

In this case, in the high opening ratio structure, the black matrix 220 may not be formed corresponding to the gate wiring and the data wiring 204 (not shown).

Next, corresponding to the pixel area P, red, green, and red color filters 218a and 218b and 218c of FIG. 6 are formed.

Next, a planarization layer 222 is formed by applying a transparent organic material to the entire surface of the substrate 200 on which the color filters 218a and 218b and 218c of FIG. 6 are formed, and the color filters 218a and 218b of FIG. 6. A transparent pixel electrode 224 in contact with the drain electrode 214 is formed on the planarization layer 222 corresponding to 218c.

Through the above-described process, an array substrate for a liquid crystal display device having a COT structure can be manufactured, and the array substrate thus manufactured and the upper substrate described above are bonded to each other through a sealant to form a liquid crystal panel.

In this case, the sealant 260 of FIG. 4 is coated around the liquid crystal panel, and is formed in a region, that is, a link region, between the gate line 204 and the gate pad 206 and between the data pad DP and the data line DL. Coated.

In the process of bonding the upper substrate 250 (FIG. 4) and the lower substrate 200 (FIG. 4), a bonding key is used. First, the upper substrate 250 (FIG. 4) and the lower substrate (200 200) After the bonding is completely bonded through the fine adjustment using the bonding key (254b of FIG. 4).

Next, the upper substrate 250 is cut to expose the gate pad 206 and the data pad DP. In this process, the bonding key 252a is removed.

Meanwhile, in order to finely adjust the upper substrate 250 and the lower substrate 200 in the aforementioned bonding process, the two substrates 200 and 250 are moved together, and the light leakage preventing pattern (254b of FIG. 4) is Since the lower organic layer 252b exists, one side of the organic layer 252b and the uppermost layer of the lower substrate 200 come into contact with each other.

As a result, during the fine bonding process, the fine bonding process may not proceed properly due to the friction force between the organic layer 252b and the lower substrate 200.                     

A method for solving this problem will now be described with reference to FIG. 10.

Fig. 10 is an enlarged plan view in which a part of a plurality of spaced apart wirings is enlarged.

As illustrated, the light blocking pattern 254b and the organic layer (not shown) stacked thereon are formed on the plurality of wirings 202, and as described above, the organic layer (not shown) and the lower layer ( In order to reduce the friction, it is necessary to reduce the contact area between the organic layer and the lower layer.

Therefore, the light shielding pattern 254b and an organic layer (not shown) stacked thereon may be formed only in a region corresponding to the wiring 202 and the wiring 202.

In this case, since the opaque wiring 202 corresponding to the light leakage prevention pattern 254b serves to shield the light, there is no problem in the function of blocking the light.

The configuration of the COT liquid crystal display device and the manufacturing method thereof according to the first embodiment of the present invention have been described above.

Hereinafter, the modification of the first embodiment will be described with the second embodiment.

Second Embodiment

A feature of the second embodiment of the present invention is characterized in that, in the configuration of the first embodiment, the light leakage preventing pattern and the organic film pattern stacked thereon are formed by extending above the sealant.                     

FIG. 11 is a cross-sectional view schematically illustrating a configuration of a COT structure liquid crystal display device according to a second embodiment of the present invention.

As illustrated, the COT structure liquid crystal display device 298 according to the present invention includes a liquid crystal panel in which a lower substrate 300 and an upper substrate 350, which are array substrates, are bonded to each other through a sealant 360, and a liquid crystal panel. And a top case 380 for fixing the liquid crystal panel LP and the polarizing plate 370 on the side thereof.

The liquid crystal panel LP is divided into a display area DA where an image is actually displayed and a non-display area NDA surrounding the display area.

The display area DA is composed of hundreds of thousands to millions of pixels P depending on the size and resolution of the liquid crystal panel LP.

A gate wiring 304 is formed in one direction for each pixel P in the lower substrate, and a data wiring (not shown) is formed in a direction perpendicular to the pixel, and the gate wiring 304 and the data wiring (not shown) are formed in the lower substrate. The thin film transistor T is formed at each crossing portion, and the thin film transistor T includes a gate electrode 302, an active layer 310, a source electrode 312, and a drain electrode 314.

A gate pad 306 is formed at the end of the gate line 304, and a data pad is not formed at the end of the data line (not shown).

The red, green, and blue color filters 318a, 318b (not shown) are configured for each pixel P, and a black matrix 320 is formed corresponding to the thin film transistor T.

The pixel electrodes 224 are formed on the color filters 318a and 318b independently of each of the pixels P to form the pixel electrodes 224, and the pixel electrodes 324 are in contact with the drain electrodes 314. 314) receives the pixel voltage.

The upper electrode 350 corresponding to the lower substrate 300 configured as described above is bonded to one surface of the common electrode CL and the common electrode corresponding to the data pad and the gate pad 306. The alignment key 354a is formed, the light leakage preventing pattern 354b is formed corresponding to the periphery of the liquid crystal panel LP, and the columnar spacer 352c is formed in the region corresponding to the thin film transistor T. ).

The bonding key 354a, the light leakage preventing pattern 354b, and the columnar spacer 352c are manufactured in one mask process.

In the above-described configuration, the light leakage preventing pattern 354b is formed to extend to an upper portion of the sealant 360. In this way, there is an advantage of increasing the margin of the top case 380 covering the periphery of the liquid crystal panel LP.

The configuration of the second embodiment of the present invention as described above is similar to the configuration of FIG. 10 described above, when forming the light leakage preventing pattern 354b and the organic layer pattern 352b stacked thereon. It can be formed corresponding to the area between.

The configuration of the first and second embodiments described above is an example in which the light leakage preventing pattern and the organic layer are randomly configured to reduce friction generated between the organic layer stacked on the light shielding pattern and the uppermost layer of the lower substrate.

Hereinafter, a structure and a manufacturing method of the upper substrate in which the light leakage preventing pattern and the uppermost layer of the lower substrate do not touch will be described in the third embodiment.                     

Third Embodiment

A feature of the third embodiment according to the present invention is to form organic film patterns having different heights in one mask process.

12 is a cross-sectional view schematically illustrating a configuration of an upper substrate for a COT structure liquid crystal display device according to a third embodiment of the present invention.

As illustrated, the common electrode CL is formed on one surface of the non-display area NDA and the substrate 500 corresponding to the display area DA, and the bonding key 504a and the common electrode CL are formed on the common electrode CL. The stacked first organic film pattern 502a, the light leakage preventing pattern 504b, the stacked second organic film pattern 502b, the columnar spacer 502c, and an opaque metal pattern formed below the 504c).

In this case, the first organic layer pattern 502a, the second organic layer pattern 502b, and the columnar spacer 502c are simultaneously patterned in one mask process, but are stacked on the light leakage preventing pattern 504b. The organic layer pattern 502b is formed to have a lower height than the first organic layer pattern 502a and the columnar spacer 502c.

When the upper substrate is configured as described above, the upper substrate and the array substrate described with reference to FIGS. 7, 8, and 9 are bonded to each other, and the cross-sectional configuration of the upper substrate includes the organic layer pattern stacked on the light leakage prevention pattern and the lower substrate. It can be seen that it is not in contact with the top layer.

Therefore, no friction force is present between the organic layer pattern and the uppermost layer of the lower substrate, so that adhesion failure due to the friction force does not occur in the process of bonding the upper and lower substrates.                     

Hereinafter, a manufacturing method of an upper substrate for a COT liquid crystal display device according to a third embodiment of the present invention will be described with reference to FIGS. 13A to 13C.

As shown in FIG. 13A, indium tin oxide (ITO) and indium zinc oxide (IZO) are included on a transparent insulating substrate 500 defined as a display area DA and a non-display area NDA. A selected one of the transparent conductive metal group is deposited to form a common electrode CL.

The opaque metal layer M is formed by depositing chromium oxide (CrO _x ) having low light reflectance on the common electrode CL, and subsequently applying a transparent photosensitive organic material to form a photosensitive layer (positive characteristic) O. Form.

In this case, the non-display area NDA is divided into a bonding key area AK and an area LSPA in which the light leakage prevention pattern is to be formed, and an area LSPA in which the light leakage prevention pattern is to be formed is formed around the substrate 500. Is defined throughout.

Next, the mask 400 including the transmission part T, the blocking part S, and the semi-transmission part HS is positioned on the photosensitive layer O, and subsequently, the light is sequentially directed to the upper part of the mask 400. Irradiation is performed to expose and develop the lower photosensitive layer O.

In this case, the transflective portion HS of the mask 400 may be positioned to correspond to the light leakage prevention pattern region LSPA, and the transflective portion may be formed by coating a translucent film or forming a slit.                     

As shown in FIG. 13B, when the exposure process and the development process are performed, the non-display area NDA corresponds to the bonding key region AK and the light leakage preventing pattern region LSPA. A second organic film pattern 502b formed at a lower height is configured, and a plurality of columnar spacers 502c are formed in the display area DA at the same height as the first organic film pattern 502a.

Next, a process of wet etching the lower opaque metal layer exposed between the first organic layer pattern 502a, the second organic layer pattern 502b, and the spacer 502c is performed.

As shown in FIG. 13C, when the wet etching process is performed, an opaque metal remains only under the respective patterns.

Accordingly, the bonding key region AK has a shape in which the bonding key 504a and the transparent first organic layer pattern 592a are stacked, and the light leakage preventing pattern region LSPA is also formed of the light leakage preventing pattern 502b and the transparent agent. Two organic film patterns 504b are formed, and in the display area DA, an opaque metal third pattern 504c and a columnar spacer 502c are formed.

At this time, the columnar spacer 502c is preferably configured randomly.

In one mask process as described above, the bonding key 502a, the light leakage preventing pattern 504b, and the columnar spacer 502c may be formed on the substrate 500.

The upper substrate for the COT liquid crystal display device according to the second embodiment of the present invention can be formed by the above-described process.

 The COT liquid crystal display according to the present invention manufactured as described above has the following effects.

First, since the light leakage prevention pattern and columnar spacers can be formed in a single mask process by forming a bonding key used to join the upper substrate and the lower substrate and the liquid crystal panel, it is possible to simplify the process. Through this, there is an improvement in process yield and cost reduction.

Second, when forming the light leakage preventing pattern formed on the upper substrate and the organic layer pattern stacked thereon, the organic layer pattern and the array are patterned so as to correspond to a region between the plurality of gate wirings and the data wirings formed on the lower substrate. Since the contact area with the uppermost layer of the substrate can be reduced, it is possible to prevent adhesion failure due to the frictional force during the fine bonding process.

Third, by extending the light leakage prevention pattern to the upper portion of the sealant, there is an effect that can secure a process margin in configuring the top case.

Fourth, in the process of forming the bonding key, the light leakage prevention pattern, and the spacer in one mask process, by using a transflective portion corresponding to the light leakage prevention pattern, the height of the organic layer pattern laminated on the light leakage prevention pattern is increased. Can be lower than the height.

Therefore, when the fine alignment process is performed during the alignment process of bonding the upper substrate and the lower substrate, contact between the organic layer pattern and the lower substrate may be prevented from contacting the uppermost layer with the lower substrate, thereby preventing a poor bonding process due to frictional force. .

Claims (21)

A first substrate and a second substrate defined by a display area and a non-display area and bonded through a sealant (adhesive means); Gate wirings and data wirings disposed on one surface of the first substrate and vertically intersecting with each other to define pixel regions; A switching element positioned at an intersection point of the gate line and the data line; A color filter configured in the pixel region; A transparent pixel electrode positioned on the color filter and connected to the switching element; A bonding key formed on a non-display area of the second substrate facing the first substrate, a first pattern stacked thereon, a light leakage preventing pattern and a second pattern stacked thereon, and the bonding key formed on the display area An opaque pattern made of the same material as the prevention pattern, and a columnar spacer stacked on the opaque pattern and formed of the same material as the first and second patterns; A top case covering the periphery of the bonded first substrate and the second substrate C. O. structure (COT) structure liquid crystal display device that includes. The method of claim 1, The light leakage preventing pattern and the second pattern stacked thereon are extended to an upper portion of the sealant. The method according to any one of claims 1 to 2, The stacked light leakage preventing pattern and the second pattern correspond to the plurality of gate wirings and the data wirings of the lower substrate corresponding to each of the C. structure (COT) structure liquid crystal display device. The method of claim 1, And the second pattern has a height lower than that of the first pattern and the columnar spacer. The method of claim 1, A COT structure liquid crystal display device further comprising a black matrix as a light blocking means on the switching element. The method of claim 1, And the color filter is formed such that red, green, and blue color filters correspond to the pixel area, respectively. The method of claim 1, The switching element is a thin film transistor (COT) structure liquid crystal display device comprising a gate electrode, an active layer, a source electrode and a drain electrode. The method of claim 1, A thin film transistor (COT) structure liquid crystal display device comprising a transparent common electrode formed between the second substrate, the bonding key, a light leakage preventing pattern, and an opaque pattern. The method of claim 8, And wherein the common electrode and the pixel electrode are selected from a group of transparent conductive metals including indium tin oxide (ITO) and indium zinc oxide (IZO). The method of claim 1, The first pattern, the second pattern, and the columnar spacers are transparent organic materials having photosensitive characteristics. Defining a first substrate and a second substrate as a display area and a non-display area; Gate wiring and data wiring crossing one surface of the first substrate perpendicularly to each other to define a pixel region; Forming a switching element positioned at an intersection point of the gate line and the data line; Forming a color filter in the pixel region; Forming a transparent pixel electrode connected to the switching element on the color filter; Defining a bonding key region and a light leakage preventing region in the non-display region of the second substrate and defining a spacer region in the display region; Stacking an opaque metal layer and a transparent organic layer on one surface of the second substrate; Patterning the organic layer by a mask process to form a first pattern in the bonding key region, a second pattern in the light leakage preventing region, and a columnar spacer in the spacer region; Removing the opaque metal layer exposed between the first pattern, the second pattern and the spacer to form a bonding key at the bottom of the first pattern and a light leakage prevention pattern at the bottom of the second pattern; Contacting the first substrate and the second substrate through a sealant (adhesive means) C. O. liquid crystal display device manufacturing method comprising a. The method of claim 11, The light leakage preventing pattern and the second pattern stacked thereon are formed to extend above the sealant. The method according to any one of claims 11 to 12, The light leakage preventing pattern and the second pattern stacked thereon correspond to a plurality of gate wirings and data wiring spaced regions formed on the lower substrate, respectively. 13. The method of claim 12, And wherein the second pattern is formed at a height lower than that of the first pattern and the columnar spacers. The method of claim 14, The method in which the second pattern is formed at a height lower than that of the first pattern and the columnar spacer, Defining a non-display area including a bonding key area and a light leakage preventing area on the substrate and a display area including a spacer area on the substrate; Stacking an opaque metal layer and a transparent organic layer on one surface of the substrate on which the non-display area and the display area are defined; Placing a mask including a reflection portion corresponding to a bonding key region and a spacer region, a transflective portion corresponding to the light leakage preventing region, and a transmission portion on the transparent organic layer; The organic layer is patterned by a mask process to form a first pattern in the bonding key region, a columnar spacer in the spacer region, and a second pattern having a height lower than that of the first pattern and the columnar spacer in the light leakage preventing region. Forming a; Removing the opaque metal layer exposed between the first pattern, the second pattern, and the spacer to form a bonding key at the bottom of the first pattern and a light leakage prevention pattern at the bottom of the second pattern; C. O. (COT) manufacturing method for a liquid crystal display device comprising a. The method of claim 11, A COT structure liquid crystal display device having a black matrix as a light shielding means further formed on the switching element. The method of claim 11, And the color filter is formed such that red, green, and blue color filters correspond to the pixel region, respectively. The method of claim 11, And the switching element is a thin film transistor comprising a gate electrode, an active layer, a source electrode, and a drain electrode. The method of claim 11, And forming a common electrode on the second substrate, the stacked opaque metal layer, and the transparent organic layer. The method of claim 19, The common electrode and the pixel electrode may be formed of one selected from a group of transparent conductive metals including indium tin oxide (ITO) and indium zinc oxide (IZO). . The method of claim 11, The first pattern, the second pattern and the columnar spacer is a transparent organic material having a photosensitive characteristic C. manufacturing method of the liquid crystal display device.

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