KR20130015245A - Fringe field switching liquid crystal display device and method of fabricating the same - Google Patents

Abstract

PURPOSE: A fringe field type LCD(Liquid Crystal Display) device and a manufacturing method thereof are provided to improve charging characteristics of a pixel by reducing loads of a data line. CONSTITUTION: A column spacer(150) is formed on a part of a data line(117). The column spacer is formed by photo acrylic. A common electrode(108) is formed on a upper part of the column spacer. An area of a black matrix(106) is reduced by forming the common electrode on the data line. A parasitic capacitance is reduced between the common electrode and the data line by forming the column spacer. [Reference numerals] (AA) TFT area; (BB) Data line area

Description

Fringe field type liquid crystal display device and manufacturing method therefor {FRINGE FIELD SWITCHING LIQUID CRYSTAL DISPLAY DEVICE AND METHOD OF FABRICATING THE SAME}

The present invention relates to a fringe field type liquid crystal display device and a manufacturing method thereof, and more particularly, to a fringe field type liquid crystal display device and a method for manufacturing the same to reduce the load of the data line without the addition of a mask process. will be.

Recently, interest in information display has increased, and a demand for using portable information media has increased, and a light-weight flat panel display (FPD) that replaces a cathode ray tube (CRT) And research and commercialization are being carried out. Particularly, among such flat panel display devices, a liquid crystal display (LCD) is an apparatus for displaying an image using the optical anisotropy of a liquid crystal, and is excellent in resolution, color display and picture quality and is actively applied to a notebook or a desktop monitor have.

The liquid crystal display comprises a color filter substrate, an array substrate, and a liquid crystal layer formed between the color filter substrate and the array substrate.

Hereinafter, the structure of a typical liquid crystal display device will be described in detail with reference to FIG.

1 is an exploded perspective view schematically showing a general liquid crystal display device.

As shown in the figure, the liquid crystal display comprises a color filter substrate 5, an array substrate 10, and a liquid crystal layer (not shown) formed between the color filter substrate 5 and the array substrate 10 30).

The color filter substrate 5 includes a color filter C composed of a plurality of sub-color filters 7 for implementing colors of red (R), green (G), and blue (B); A black matrix 6 that separates the sub-color filters 7 and blocks light passing through the liquid crystal layer 30, and a transparent common electrode that applies a voltage to the liquid crystal layer 30. 8)

In addition, the array substrate 10 may be arranged vertically and horizontally to define a plurality of gate lines 16 and data lines 17 and a plurality of gate lines 16 and data lines 17 that define a plurality of pixel regions P. A thin film transistor (TFT) T, which is a switching element formed in an intersection region, and a pixel electrode 18 formed on the pixel region P are included.

The color filter substrate 5 and the array substrate 10 configured as described above are joined to face each other by sealants (not shown) formed on the outer side of the image display area to form a panel, and the color filter substrate 5 And the bonding of the array substrate 10 is made through a bonding key (not shown) formed in the color filter substrate 5 or the array substrate 10.

At this time, the driving method generally used in the liquid crystal display device is a twisted nematic (TN) method for driving the nematic liquid crystal molecules in a vertical direction with respect to the substrate, but the liquid crystal display device of the twisted nematic method Has the disadvantage that the viewing angle is as narrow as 90 degrees. This is due to the refractive anisotropy of the liquid crystal molecules because the liquid crystal molecules oriented horizontally with the substrate are oriented almost perpendicular to the substrate when a voltage is applied to the panel.

Accordingly, there is an in-plane switching (IPS) type liquid crystal display device in which the liquid crystal molecules are driven in a horizontal direction with respect to the substrate to improve the viewing angle to 170 degrees or more.

FIG. 2 is a cross-sectional view of a portion of a transverse electric field type liquid crystal display device, in which a fringe field formed between a pixel electrode and a common electrode penetrates a slit to drive liquid crystal molecules positioned on a pixel region and a common electrode to implement an image A cross-sectional structure of a fringe field switching (FFS) liquid crystal display device is shown.

In the fringe field type liquid crystal display, the liquid crystal molecules are horizontally aligned, and as the pixel electrode is formed at the bottom and the common electrode is formed at the top, an electric field is generated in the horizontal and vertical directions so that the liquid crystal molecules are twisted. It is tilted and driven.

As shown in the drawing, the fringe field type liquid crystal display device is largely divided between the color filter substrate 5 as the first substrate and the array substrate 10 as the second substrate, and the color filter substrate 5 and the array substrate 10. And a column spacer 50 between the color filter substrate 5 and the array substrate 10 to form a column spacer 50 between the color filter substrate 5 and the array substrate 10. Keep the cell gap constant.

The color filter substrate 5 may include a black matrix that distinguishes between a color filter composed of red, green, and blue sub color filters 7 and the sub color filter 7 and blocks light transmitted through the liquid crystal layer. 6) and an overcoat layer 9 formed on the color filter and the black matrix 6.

A gate line (not shown) and a data line 17 are formed in the array substrate 10 to be arranged horizontally and horizontally to define a pixel area, and in the intersection area of the gate line and the data line 17, that is, in the TFT area. A thin film transistor which is a switching element is formed.

In this case, the thin film transistor includes a gate electrode 21 connected to the gate line, a source electrode 22 connected to the data line 17, and a drain electrode 23 connected to the pixel electrode 18. In addition, the thin film transistor is formed by the gate insulating film 15a for insulation between the gate electrode 21 and the source / drain electrodes 22 and 23 and the gate electrode supplied by the gate voltage supplied to the gate electrode 21. An active layer 24 is formed between the 22 and the drain electrode 23 to form a conductive channel.

In this case, the source / drain regions of the active layer 24 form ohmic contacts with the source / drain electrodes 22 and 23 through an ohmic contact layer 25n.

The common electrode 8 and the pixel electrode 18 are formed in the pixel region, and the common electrode 8 is formed together with the pixel electrode 18 in a box shape to generate a fringe field. 8, a plurality of slits 8s are included.

In this case, the pixel electrode 18 is electrically connected to the drain electrode 23 through contact holes formed in the first insulating film 15b and the second insulating film 15c, and the common electrode 8 is a pixel electrode. The pixel electrode 18 is insulated from each other by the third insulating film 15d formed on the upper portion 18.

The fringe field type liquid crystal display device has a wide viewing angle, and when the common electrode 8 is formed on the data line 17, the black matrix 6 area can be reduced to increase the aperture ratio. have.

However, parasitic capacitance is generated due to overlap between the common electrode 8 and the data line 17, which is a charging characteristic according to an increase in load of the data line 17. Deterioration, an increase in the size of the thin film transistor, and an increase in power consumption are caused.

In order to reduce this, when a photo acryl having a low dielectric constant is applied to the second insulating layer 15c on the data line 17, a mask process (ie, a photolithography process) is performed. Will be added. That is, in the conventional case, the pixel electrode and the drain electrode are in direct contact, while in the case of applying photoacrylic, the photolithography process is required once more because the aforementioned contact hole is required.

The photolithography process is a series of processes in which a pattern drawn on a mask is transferred onto a substrate on which a thin film is deposited to form a desired pattern. The photolithography process includes a plurality of processes such as photoresist coating, exposure, and development processes. It has the disadvantage of dropping.

In particular, a mask designed to form a pattern is very expensive, and as the number of masks applied to the process increases, the manufacturing cost of the liquid crystal display device increases in proportion thereto.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problem, and an object of the present invention is to provide a fringe field type liquid crystal display device and a method for manufacturing the same, which reduce power consumption by reducing the load on a data line in a high resolution fringe field type liquid crystal display device. have.

Another object of the present invention is to provide a fringe field type liquid crystal display device and a method of manufacturing the same, which reduce the load on the data line without adding a mask process.

Other objects and features of the present invention will be described in the configuration and claims of the invention which will be described later.

In order to achieve the above object, the fringe field type liquid crystal display device of the present invention comprises a gate electrode and a gate line formed on the first substrate; A gate insulating film formed on the first substrate on which the gate electrode and the gate line are formed; An active layer formed on the gate electrode on which the gate insulating film is formed; A pixel electrode formed in the pixel region of the first substrate on which the active layer is formed; A data line defining the pixel region by crossing the source electrode, the drain electrode, and the gate line formed on the active layer of the first substrate on which the pixel electrode is formed; A column spacer formed of an organic insulating material on the data line to maintain a cell gap between the first substrate and the second substrate; A protective film formed on the first substrate on which the column spacer is formed; A common electrode formed on the first substrate on which the passivation layer is formed and having a plurality of slits in the pixel region; And the second substrate bonded to face the first substrate.

In this case, the column spacer is made of an organic insulating material having a low dielectric constant such as photo acryl.

The column spacer may have a predetermined length along the data line to be separated in each pixel area.

The column spacer may include a gap spacer for maintaining a cell gap between the first substrate and the second substrate, and a press spacer for buffering a pressure when a pressure is applied to the panel surface.

The gap spacer and the pressing spacer may have different heights.

Method of manufacturing a fringe field type liquid crystal display device of the present invention comprises the steps of providing a first substrate and a second substrate; Forming a gate electrode and a gate line on the first substrate; Forming a gate insulating film on the first substrate on which the gate electrode and the gate line are formed; Forming an active layer on the gate electrode on which the gate insulating film is formed; Forming a pixel electrode in the pixel region of the first substrate on which the active layer is formed; Forming a source electrode and a drain electrode on the active layer of the first substrate on which the pixel electrode is formed, and forming a data line crossing the gate line to define the pixel region; Forming a column spacer formed of an organic insulating material on the data line to maintain a cell gap between the first substrate and the second substrate; Forming a protective film on the first substrate on which the column spacer is formed; Forming a common electrode having a plurality of slits in a pixel area of the first substrate on which the passivation layer is formed; And bonding the first substrate and the second substrate to each other.

In this case, the column spacer is formed of an organic insulating material having a low dielectric constant such as photo acryl.

The column spacer is formed only on the data line.

The column spacer may be formed to have a predetermined length along the data line.

The column spacer may be formed to have a predetermined length along the data line to be separated in each pixel area.

The column spacer may include a gap spacer for maintaining a cell gap between the first substrate and the second substrate, and a press spacer for buffering a pressure when a pressure is applied to the panel surface.

In this case, the gap spacer and the pressed spacer are formed to have different heights.

The gap spacer and the pressing spacer may be formed to have different heights by using a half-tone mask or a diffraction mask.

As described above, in the fringe field type liquid crystal display device and the manufacturing method thereof, the charging characteristic of the pixel is improved as the load of the data line is reduced. As a result, while the performance of the thin film transistor is improved, the size of the thin film transistor can be reduced, thereby providing an effect of improving the aperture ratio. In addition, as the load on the data line is reduced, the power consumption required to drive the panel is reduced to one-quarter.

In particular, the fringe field type liquid crystal display device and the method of manufacturing the same according to the present invention form a column spacer with photoacryl on the data line, and then form a common electrode on the data line and the common electrode without adding a mask process. Capacitance in between can be reduced, resulting in reduced manufacturing processes and costs.

1 is an exploded perspective view schematically showing a general liquid crystal display device.
2 is a schematic cross-sectional view of a fringe field type liquid crystal display device;
3 is a schematic cross-sectional view of a fringe field type liquid crystal display device according to a first embodiment of the present invention;
4 is a plan view schematically illustrating a portion of an array substrate of a fringe field type liquid crystal display device according to a first embodiment of the present invention;
5A to 5G are cross-sectional views sequentially illustrating a manufacturing process of the array substrate illustrated in FIG. 4.
6A to 6G are plan views sequentially illustrating a manufacturing process of the array substrate illustrated in FIG. 4.
7 is a schematic cross-sectional view of a fringe field type liquid crystal display device according to a second exemplary embodiment of the present invention.
8 is a plan view schematically illustrating a portion of an array substrate of a fringe field type liquid crystal display device according to a second exemplary embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the fringe field type liquid crystal display device and a method of manufacturing the same.

3 is a schematic cross-sectional view of a fringe field type liquid crystal display device according to a first embodiment of the present invention.

4 is a plan view schematically illustrating a portion of an array substrate of a fringe field type liquid crystal display device according to a first embodiment of the present invention, in which a fringe field formed between a pixel electrode and a common electrode penetrates a slit, A fringe field type liquid crystal display device for realizing an image by driving liquid crystal molecules positioned on a pixel electrode is shown.

At this time, in the actual liquid crystal display device, the N gate lines and the M data lines cross each other and there are M × N pixels. However, for simplicity, one pixel is shown in the figure. 3 illustrates a portion of a pixel portion including a TFT region and a data line region, and FIG. 4 illustrates one pixel including a pixel portion, a data pad portion, and a gate pad portion.

As shown in the figure, the fringe field type liquid crystal display device according to the first embodiment of the present invention is largely the color filter substrate 105 as the first substrate, the array substrate 110 as the second substrate and the color filter substrate ( It consists of a liquid crystal layer (not shown) formed between the 105 and the array substrate 110, a column spacer 150 is formed between the color filter substrate 105 and the array substrate 110 to the color filter substrate 105 ) And the cell gap between the array substrate 110 is kept constant.

The color filter substrate 105 may include a black matrix that distinguishes between a color filter composed of red, green, and blue sub color filters 107 and the sub color filter 107 and blocks light transmitted through the liquid crystal layer ( 106, and an overcoat layer 109 formed on the color filter and the black matrix 106.

A gate line 116 and a data line 117 are formed in the array substrate 110 to define a pixel area vertically and horizontally, and an intersection area of the gate line 116 and the data line 117, that is, a TFT, is formed. In the region, a thin film transistor serving as a switching element is formed.

In this case, the thin film transistor includes a gate electrode 121 connected to the gate line 116, a source electrode 122 connected to the data line 117, and a drain electrode 123 connected to the pixel electrode 118. In addition, the thin film transistor is connected to the source electrode by the gate insulating film 115a for insulation between the gate electrode 121 and the source / drain electrodes 122 and 123 and the gate voltage supplied to the gate electrode 121. An active layer 124 forming a conductive channel between the 122 and the drain electrode 123.

In this case, the source / drain regions of the active layer 124 form ohmic contacts with the source / drain electrodes 122 and 123 through the ohmic contact layer 125n.

Here, the common electrode 108 and the pixel electrode 118 are formed in the pixel region, wherein the common electrode 108 is formed together with the pixel electrode 118 in a box shape to generate a fringe field. A plurality of slits 108s are included in the electrode 108. That is, the common electrode 108 and the pixel electrode 118 for generating a fringe field are formed in the pixel region, wherein the pixel electrode 118 is formed in a box shape in the pixel region, and the common The electrode 108 is formed in a single pattern throughout the pixel portion and is formed to have a plurality of slits 108s in each pixel region.

In this case, the drain electrode 123 is formed on the pixel electrode 118 to be directly connected to the pixel electrode 118, and the common electrode 108 is formed on the passivation layer 115b formed on the pixel electrode 118. It is insulated from the pixel electrode 118 by this.

As described above, the liquid crystal display device according to the first exemplary embodiment of the present invention shows a fringe field type liquid crystal display device which drives a liquid crystal molecule by inducing a fringe field having a parabolic transverse electric field in the liquid crystal layer. However, the present invention is not limited thereto.

In addition, since the common electrode 108 is also formed on the data line 117 as described above, the area of the black matrix 106 can be reduced so that the aperture ratio is improved, and the photo having a low dielectric constant on the data line 117 is provided. As the column spacer 150 made of acrylic is formed, parasitic capacitance between the common electrode 108 and the data line 117 can be reduced. As a result, the load of the data line is reduced to improve the charging characteristic of the pixel, and the power consumption required to drive the panel is reduced to 1/4 of the structure of the conventional silicon insulating layer based on 4.5 inch HD, for example.

In the fringe field type liquid crystal display according to the first exemplary embodiment of the present invention, after forming the column spacer 150 made of photoacryl on the data line 117, the common electrode is formed on the data line 117. Forming 108 allows the parasitic capacitance between common electrode 108 and data line 117 to be reduced without the addition of a mask process, thereby reducing the manufacturing process and cost. That is, the photo acryl replaces the column spacer applied in the existing color filter process in addition to reducing the parasitic capacitance between the common electrode and the data line, thereby preventing the mask process from being added.

To this end, the photo acryl is not formed on the entire surface of the thin film transistor, but is formed only on the data line 117 to serve as a column spacer 150. When the photo acryl is applied as the column spacer 150, the entire column spacer Because the density of D should not be too large, a design that minimizes column spacer density should be considered.

The gate pad electrode 126p and the data pad electrode 127p electrically connected to the gate line 116 and the data line 117 are formed in the edge region of the array substrate 110 configured as described above. The scan signal and the data signal applied from the driving circuit unit (not shown) are transferred to the gate line 116 and the data line 117, respectively.

That is, the gate line 116 and the data line 117 extend toward the driving circuit part and are connected to the corresponding gate pad line 116p and the data pad line 117p, respectively, and the gate pad line 116p and the data pad The line 117p receives the scan signal and the data signal from the driving circuit unit through the gate pad electrode 126p and the data pad electrode 127p electrically connected to the gate pad line 116p and the data pad line 117p, respectively. You will be authorized.

In this case, the data pad electrode 127p is electrically connected to the data pad line 117p through the first contact hole 140a and the gate pad electrode 126p is connected to the gate through the second contact hole 140b. It is electrically connected to the pad line 116p.

Hereinafter, a method of manufacturing a fringe field type liquid crystal display device according to a first embodiment of the present invention configured as described above will be described in detail with reference to the accompanying drawings.

5A through 5G are cross-sectional views sequentially illustrating a manufacturing process of the array substrate illustrated in FIG. 4, and a process of manufacturing an array substrate of a TFT region and a data line region, and an array substrate of a data pad region and a gate pad region, respectively. It is shown.

6A to 6G are plan views sequentially illustrating a manufacturing process of the array substrate illustrated in FIG. 4.

As shown in FIGS. 5A and 6A, a gate electrode 121 and a gate line 116 are formed in a TFT region of an array substrate 110 made of a transparent insulating material such as glass, and the array substrate 110 may be formed. The gate pad line 116p is formed in the gate pad area.

In this case, the gate electrode 121, the gate line 116, and the gate pad line 116p are selectively deposited through a photolithography process (first mask process) after depositing a first conductive layer on the entire surface of the array substrate 110. It is formed by patterning.

Here, the first conductive layer may include aluminum (Al), aluminum alloy (Al alloy), tungsten (W), copper (Cu), chromium (Cr), molybdenum (Mo), and Low resistance opaque conductive materials such as molybdenum alloys can be used. The first conductive layer may have a multilayer structure in which two or more low resistance conductive materials are stacked.

Next, as shown in FIGS. 5B and 6B, the gate insulating layer 115a and the amorphous silicon are formed on the entire surface of the array substrate 110 on which the gate electrode 121, the gate line 116, and the gate pad line 116p are formed. A thin film and an n + amorphous silicon thin film are formed.

Thereafter, the amorphous silicon thin film and the n + amorphous silicon thin film are selectively removed through a photolithography process (second mask process) to form an active layer 124 made of the amorphous silicon thin film in the TFT region of the array substrate 110. do.

In this case, the n + amorphous silicon thin film pattern 125 is formed on the active layer 124 and patterned in substantially the same shape as the active layer 124.

Next, as shown in FIGS. 5C and 6C, a second conductive layer is formed on the entire surface of the array substrate 110 on which the active layer 124 and the n + amorphous silicon thin film pattern 125 are formed. In this case, the second conductive layer includes a transparent conductive material having excellent transmittance such as indium tin oxide (ITO) or indium zinc oxide (IZO) to form a pixel electrode.

Thereafter, the second conductive layer is selectively removed through a photolithography process (a third mask process) to form a box-shaped pixel electrode 118 formed of the second conductive layer in the pixel region of the array substrate 110. .

5D and 6D, a third conductive layer is formed on the entire surface of the array substrate 110 on which the pixel electrode 118 is formed. In this case, the third conductive layer may be made of a low resistance opaque conductive material such as aluminum, aluminum alloy, tungsten, copper, chromium, molybdenum and molybdenum alloy to form a source electrode, a drain electrode, and a data line. The third conductive layer may have a multilayer structure in which two or more low resistance conductive materials are stacked.

Thereafter, the n + amorphous silicon thin film and the third conductive film are selectively removed through a photolithography process (a fourth mask process), so that the source electrode 122 and the drain electrode formed of the third conductive film on the active layer 124. 123 is formed.

In this case, a data line 117 made of the third conductive layer is formed in the data line region of the array substrate 110 through the fourth mask process, and at the same time, the third data pad region of the array substrate 110 is formed. A data pad line 117p made of a conductive film is formed.

In this case, an ohmic contact layer formed of the n + amorphous silicon thin film on the active layer 124 and ohmic contact between the source / drain region of the active layer 124 and the source / drain electrodes 122 and 123. 125n is formed.

In this case, a part of the drain electrode 123 is directly formed on the pixel electrode 118 below and electrically connected to the pixel electrode 118.

Next, as shown in FIGS. 5E and 6E, photoacrylic is formed on the entire surface of the array substrate 110 on which the source / drain electrodes 122 and 123, the data line 117, and the data pad line 117p are formed. After forming an organic insulating material having a low dielectric constant, a column spacer 150 made of the organic insulating material is formed on the data line 117 by selectively removing the organic insulating material through a photolithography process (a fifth mask process).

At this time, as described above, the column spacer 150 serves to replace the column spacer applied in the existing color filter process in addition to reducing the parasitic capacitance between the common electrode to be formed next and the data line 117. Done.

In addition, the column spacer 150 is not formed on the entire surface of the thin film transistor, but is formed only on the data line 117 to serve as the column spacer 150, and when the photo acryl is applied as the column spacer 150. Since the density of the entire column spacer should not be too large, a design that minimizes the column spacer density should be considered. For example, as illustrated, the column spacer 150 according to the first embodiment of the present invention may be formed to cover a portion of the data line 117.

For example, the column spacer 150 may be formed only on the data line 117 and may have a predetermined length along the data line 117. In addition, the column spacer 150 may be formed to have a predetermined length along the data line 117 so as to be separated in each pixel area.

Next, as shown in FIGS. 5F and 6F, the passivation layer 115b is formed on the entire surface of the array substrate 110 on which the column spacer 150 is formed.

In this case, the passivation layer 115c may be formed of an inorganic insulating layer such as silicon nitride layer (SiNx) or silicon oxide layer (SiO ₂ ).

In addition, the protective film 115b and the gate insulating film 115a are selectively removed through a photolithography process (a sixth mask process), respectively, in the data pad region and the gate pad region of the array substrate 110. A first contact hole 140a and a second contact hole 140b exposing a portion 117p and a portion of the gate pad line 116p are formed.

5G and 6G, after forming a fourth conductive film made of a transparent conductive material on the entire surface of the array substrate 110 on which the protective film 115b is formed, a photolithography process (seventh mask process) is performed. By selectively patterning the same, a common electrode 108 having a plurality of slits 108s is formed in the pixel region.

In this case, by selectively patterning the fourth conductive layer using the seventh mask process, the data pads are formed through the first contact hole 140a and the second contact hole 140b in the data pad region and the gate pad region, respectively. The data pad electrode 127p and the gate pad electrode 126p electrically connected to the line 117p and the gate pad line 116p are formed.

The array substrate according to the first embodiment of the present invention configured as described above is bonded to the color filter substrate by a sealant formed on the outside of the image display area, wherein the color filter substrate includes the thin film transistor, the gate line, and the data line. Black matrix to prevent light leakage and color filter to realize red, green and blue colors are formed.

At this time, the color filter substrate and the array substrate are bonded together through a covalent key formed on the color filter substrate or the array substrate.

Meanwhile, in order to secure the liquid crystal margin, a dual gap structure may be formed using a half-tone mask or a diffraction mask when forming the column spacer, which will be described in detail with reference to the second embodiment of the present invention.

FIG. 7 is a schematic cross-sectional view of a fringe field type liquid crystal display device according to a second exemplary embodiment of the present invention, and illustrates a cross-sectional structure of a liquid crystal display device including two adjacent data line regions.

8 is a plan view schematically illustrating a portion of an array substrate of a fringe field type liquid crystal display according to a second exemplary embodiment of the present invention, and illustrates a portion of the array substrate on which 6x2 pixels are illustrated.

As shown in the figure, the fringe field type liquid crystal display device according to the second embodiment of the present invention is largely a color filter substrate 205 which is a first substrate, an array substrate 210 which is a second substrate, and the color filter substrate ( 205 and a liquid crystal layer (not shown) formed between the array substrate 210 and column spacers 250 and 255 are formed between the color filter substrate 205 and the array substrate 210 to form the color filter substrate. The cell gap between 205 and array substrate 210 is kept constant.

The color filter substrate 205 distinguishes between a color filter composed of red, green, and blue sub-color filters 207 and the sub-color filter 207 and blocks a black matrix that blocks light transmitted through the liquid crystal layer. 206, and an overcoat layer 209 formed on the color filter and the black matrix 206.

A gate line 216 and a data line 217 are formed in the array substrate 210 to define a pixel area vertically and horizontally, and an intersection area of the gate line 216 and the data line 217, that is, a TFT, is formed. In the region, a thin film transistor serving as a switching element is formed.

Although not shown in the drawing, the thin film transistor includes a gate electrode connected to the gate line 216, a source electrode connected to the data line 217, and a drain electrode connected to the pixel electrode. The thin film transistor may further include an active layer forming a conductive channel between the source electrode and the drain electrode by a gate insulating film 215a for insulating the gate electrode and a source / drain electrode and a gate voltage supplied to the gate electrode. It includes.

The common electrode 208 and the pixel electrode 218 are formed in the pixel area, and the common electrode 208 together with the box-shaped pixel electrode 218 generates the fringe field together with the common electrode ( 208 includes a number of slits 208s. That is, the common electrode 208 and the pixel electrode 218 for generating a fringe field are formed in the pixel region. In this case, the pixel electrode 218 is formed in a box shape in the pixel region. The electrode 208 is formed in a single pattern over the entire pixel portion and is formed to have a plurality of slits 208s in each pixel region.

In this case, the drain electrode is formed on the pixel electrode 218 to be directly connected to the pixel electrode 218, and the common electrode 208 is formed by the passivation layer 215b formed on the pixel electrode 218. It is insulated from the electrode 218.

As described above, the liquid crystal display according to the second exemplary embodiment of the present invention shows a fringe field type liquid crystal display device which drives a liquid crystal molecule by inducing a fringe field having a parabolic transverse electric field in the liquid crystal layer. However, the present invention is not limited thereto.

In addition, since the common electrode 208 is formed on the data line 217 as described above, the black matrix 206 can be reduced in size so that the aperture ratio can be improved, and the photo having a low dielectric constant on the data line 217 can be reduced. As the column spacers 250 and 255 made of acrylic are formed, parasitic capacitance between the common electrode 208 and the data line 217 can be reduced. As a result, the load of the data line is reduced to improve the charging characteristic of the pixel, and the power consumption required to drive the panel is reduced.

In addition, in the fringe field type liquid crystal display according to the second embodiment of the present invention, column spacers 250 and 255 made of photoacryl are formed on the data line 217 as in the first embodiment of the present invention. After forming, by forming the common electrode 208 thereon, the parasitic capacitance between the common electrode 208 and the data line 217 can be reduced without adding a mask process, thereby reducing the manufacturing process and cost. to provide.

To this end, the photo acryl is not formed on the entire surface of the thin film transistor, but is formed only on the data line 217 to serve as column spacers 250 and 255, and the photo acryl is applied to the column spacers 250 and 255. In this case, the density of the entire column spacer should not be too large, so a design that minimizes the column spacer density should be considered.

Meanwhile, the column spacers 250 and 255 according to the second embodiment of the present invention may pressurize the gap spacer 250 and the panel surface to maintain the cell gap between the color filter substrate 205 and the array substrate 210. When applied, it is characterized by consisting of a pressing spacer 255 for buffering it.

In this case, the pressing spacer 255 together with the gap spacer 250 maintains a constant cell gap between the color filter substrate 205 and the array substrate 210, and when the pressure is applied to the panel surface. It may be formed on the data line 217 to buffer the pressure.

The pressing spacer 255 has a height lower than that of the gap spacer 250 such that the pressing spacer 255 comes into contact with the upper color filter substrate 205 only when the panel is pressed by an external pressure. The height difference of the pressing spacer 255 may be formed using a half-tone mask or a diffraction mask.

In the drawing, a case where one gap spacer 250 and nine pressing spacers 255 are formed per 5 × 2 pixels is illustrated as an example, but the present invention is not limited thereto.

In the fringe field type liquid crystal display device of the first and second embodiments of the present invention, an amorphous silicon thin film transistor using an amorphous silicon thin film as an active layer is described as an example, but the present invention is not limited thereto. The same applies to polycrystalline silicon thin film transistors using polycrystalline silicon thin films as active layers.

In addition, the present invention can be applied not only to a liquid crystal display device but also to other display devices manufactured using thin film transistors, for example, organic electroluminescent display devices in which organic light emitting diodes (OLEDs) have.

Many details are set forth in the foregoing description but should be construed as illustrative of preferred embodiments rather than to limit the scope of the invention. Therefore, the invention should not be construed as limited to the embodiments described, but should be determined by equivalents to the appended claims and the claims.

105,205: Color filter substrate 106,206: Black matrix
107,207: sub color filter 108,208: common electrode
108s, 208s: slit 109,209: overcoat layer
110, 210: array substrate 116, 216: gate line
117,217 data line 118,218 pixel electrode
150,250,255: Column spacer

Claims (13)

Providing a first substrate and a second substrate;
Forming a gate electrode and a gate line on the first substrate;
Forming a gate insulating film on the first substrate on which the gate electrode and the gate line are formed;
Forming an active layer on the gate electrode on which the gate insulating film is formed;
Forming a pixel electrode in the pixel region of the first substrate on which the active layer is formed;
Forming a source electrode and a drain electrode on the active layer of the first substrate on which the pixel electrode is formed, and forming a data line crossing the gate line to define the pixel region;
Forming a column spacer formed of an organic insulating material on the data line to maintain a cell gap between the first substrate and the second substrate;
Forming a protective film on the first substrate on which the column spacer is formed;
Forming a common electrode having a plurality of slits in a pixel area of the first substrate on which the passivation layer is formed; And
A method of manufacturing a fringe field type liquid crystal display device comprising the step of bonding the first substrate and the second substrate. The method of claim 1, wherein the column spacer is formed of an organic insulating material having a low dielectric constant such as photoacrylic. The method of claim 1, wherein the column spacer is formed only on the data line. 2. The method of claim 1, wherein the column spacer is formed to have a predetermined length along the data line. 2. The method of claim 1, wherein the column spacers are formed to have a predetermined length along the data lines so as to be separated in each pixel area. The fringe field of claim 1, wherein the column spacer comprises a gap spacer for maintaining a cell gap between the first substrate and a second substrate, and a press spacer for buffering a pressure when a pressure is applied to the panel surface. Method of manufacturing a type liquid crystal display device. 7. The method of claim 6, wherein the gap spacer and the pressing spacer are formed to have different heights. 7. The method of claim 6, wherein the gap spacer and the depression spacer are formed to have different heights by using a half-tone mask or a diffraction mask. A gate electrode and a gate line formed on the first substrate;
A gate insulating film formed on the first substrate on which the gate electrode and the gate line are formed;
An active layer formed on the gate electrode on which the gate insulating film is formed;
A pixel electrode formed in the pixel region of the first substrate on which the active layer is formed;
A data line defining the pixel region by crossing the source electrode, the drain electrode, and the gate line formed on the active layer of the first substrate on which the pixel electrode is formed;
A column spacer formed of an organic insulating material on the data line to maintain a cell gap between the first substrate and the second substrate;
A protective film formed on the first substrate on which the column spacer is formed;
A common electrode formed on the first substrate on which the passivation layer is formed and having a plurality of slits in the pixel region; And
A fringe field type liquid crystal display device comprising the second substrate bonded to face the first substrate. 10. The fringe field type liquid crystal display of claim 9, wherein the column spacer is made of an organic insulating material having a low dielectric constant such as photoacrylic. 10. The fringe field type liquid crystal display device according to claim 9, wherein the column spacers have a predetermined length along the data lines so as to be separated in each pixel area. 10. The fringe field of claim 9, wherein the column spacer comprises a gap spacer for maintaining a cell gap between the first substrate and a second substrate, and a press spacer for buffering a pressure when a pressure is applied to the panel surface. Type liquid crystal display device. 10. The fringe field type liquid crystal display device according to claim 9, wherein the gap spacer and the pressing spacer have different heights.

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