KR20030050577A - liquid crystal display, color filter plate and method for fabricating the plate - Google Patents

Abstract

PURPOSE: A liquid crystal display, a color filter substrate of the display and a method for fabricating the substrate are provided to maintain a narrow cell gap uniformly and simplify a process of fabricating the color filter substrate. CONSTITUTION: A liquid crystal display includes the first insulating substrate(10), the second insulating substrate(100) combined with the first substrate, a plurality of conductive lines(25) formed on the inner side of the first substrate to define pixel regions in a matrix form, a plurality of switching elements formed on the inner side of the first substrate and connected to the conductive lines, and a plurality of pixel electrodes(102) formed on the inner side of the first substrate and connected to the switching elements respectively. The display further includes a color filter(200) formed on the inner side of the second substrate, a passivation layer(300) covering the color filter, and a plurality of column spacers(350) that are integrated with the passivation layer and support a distance between the first and second substrates.

Description

Liquid crystal display device, color filter substrate and its manufacturing method {liquid crystal display, color filter plate and method for fabricating the plate}

The present invention relates to a liquid crystal display device, a color filter substrate thereof and a manufacturing method thereof.

In general, a liquid crystal display device injects a liquid crystal material between an upper substrate on which a common electrode, a color filter, and the like are formed, and a lower substrate on which a thin film transistor and a pixel electrode are formed. By applying a different potential to form an electric field to change the arrangement of the liquid crystal molecules, and through this to adjust the transmittance of light to express the image.

In such a liquid crystal display device, a substrate spacer is used to maintain a uniform gap between two substrates, but the substrate spacer is generally used as a spherical spacer having elasticity.

However, as the spacing between two substrates becomes narrower, there is a limit in maintaining cell spacing evenly by using a spherical spacer having fluidity. May cause severe stains or afterimages.

In addition, when manufacturing the color filter substrate, the manufacturing process is complicated because the protective film covering the color filter must be flattened to minimize the step by the color filter.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a liquid crystal display device capable of maintaining a narrow cell gap uniformly and minimizing spots when applied to a contact method.

In addition, another object of the present invention is to provide a color filter substrate and a method of manufacturing the same that can simplify the manufacturing process.

1 is a layout view of a liquid crystal display according to an exemplary embodiment of the present invention.

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

3 is a cross-sectional view of a color filter substrate in a first step of manufacturing a color filter substrate for a liquid crystal display according to an exemplary embodiment of the present invention.

4 is a view showing a cross section of the color filter substrate in the next step of FIG.

5 is a view showing a cross section of the completed color filter substrate.

In order to achieve this object, in the present invention, when forming a protective film covering the color filter on the color filter substrate, pillar spacers for supporting the two substrates at uniform intervals are simultaneously formed.

Specifically, the liquid crystal display of the present invention is formed on the first insulating substrate, the second insulating substrate having an inner surface facing the inner surface of the first substrate and bonded to the first substrate, the inner surface of the first substrate, and having a matrix form. A plurality of wirings defining a pixel area of the substrate, a plurality of switching elements formed on an inner surface of the first substrate and connected to the wirings, a plurality of pixel electrodes formed on an inner surface of the first substrate and connected to the switching elements, A color filter sequentially formed on an inner surface of the second substrate of the pixel region, a protective film covering the color filter on the inner surface of the second substrate, and integrally formed with a flattened protective film and a protective film and disposed between the pixel regions and thicker than the protective film. It is formed to include a plurality of pillar spacers for supporting the gap between the first and second substrate.

The display device may further include a common electrode formed on the passivation layer on the inner surface of the second substrate, and the pixel electrode and the common electrode may have an opening or protrusion pattern.

The liquid crystal display may further include a liquid crystal circulated in the vertical direction between the first and second substrates.

The liquid crystal may further include a liquid crystal between the first and second substrates, and the liquid crystal may be twisted and oriented between the upper and lower substrates, and the twist angle may have a value between 80 ° and 100 °.

The liquid crystal may further include a liquid crystal between the first and second substrates, and the liquid crystal may be twisted and aligned between the upper and lower substrates, and the twist angle may have a value between 250 ° and 300 °.

On the other hand, the color filter substrate according to the present invention is integrally formed with an insulating substrate, a color filter formed on the inner surface of the insulating substrate, a protective film which covers the color filter on the inner surface of the insulating substrate and is flattened, and the protective film. It includes a plurality of pillar spacers having a thickness thicker than the protective film, the common electrode formed on the protective film and the pillar spacer as a whole.

Herein, the color filters include red (R), green (G), and blue (B) color filters sequentially arranged for each pixel column of a plurality of pixel regions, and both ends of the color filter are adjacent to each other. It is preferable that they are formed to overlap each other.

In addition, it is preferable that pillar spacers made of the same material as the passivation layer are formed above the overlapping ends of the color filter, and the pillar spacers may be linearly formed.

Moreover, it is preferable that the thickness of the said protective film is 0.8 micrometer-1.5 micrometers, and the thickness of the said pillar spacer was formed in 2.5 micrometers-3.5 micrometers.

On the other hand, the manufacturing method of the color filter substrate for liquid crystal display devices of this invention is as follows.

First, a color filter is formed on a transparent substrate. Next, a protective film and pillar spacers are formed on the color filter. A common electrode made of a transparent conductive material is formed on the passivation layer and the pillar spacer. At this time, the protective film and the spacer are formed at the same time using a mask having a partially different transmittance.

Here, the protective film and the pillar spacer may be formed using a negative or positive photosensitive resin.

In the color filter, stripe-shaped red (R), green (G), and blue (B) color filters are sequentially arranged, and both ends of the color filter are preferably overlapped with each other.

At this time, the column spacer is preferably formed on the upper part of the overlapping both ends of the color filter.

Then, the liquid crystal display according to the exemplary embodiment of the present invention and the manufacturing method of the color filter substrate will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily practice the present invention. do.

First, the structure of a liquid crystal display according to an exemplary embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2.

1 is a layout view of a liquid crystal display according to an exemplary embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line II-II 'of FIG. 1.

First, the structure of the "lower board | substrate" of a liquid crystal display device is demonstrated.

1 and 2, the lower substrate includes aluminum (Al) or aluminum alloy, molybdenum (Mo) or molybdenum-tungsten alloy (MoW), chromium (Cr) on a transparent insulating substrate 10 such as glass. ) And gate wirings 22 and 25 made of a metal or a conductor such as tantalum (Ta) are formed. The gate wiring includes a gate line 22 extending in the horizontal direction and receiving a scan signal from the outside, and a gate electrode 25 that is a part of the gate line 22.

The gate wirings 22 and 25 may be formed in a single layer, but may be formed in a double layer or a triple layer. In the case of forming more than two layers, it is preferable that one layer is made of a material having a low resistance and the other layer is made of a material having good contact properties with other materials. For example, a double layer of Cr / Al (or an Al alloy) or Al / A bilayer of Mo can be mentioned.

A gate insulating film 30 made of silicon nitride (SiN _X ) is formed on the gate wires 22 and 25.

A semiconductor layer 42 made of a semiconductor such as amorphous silicon is formed on the gate insulating layer 30, and a semiconductor such as amorphous silicon doped with n-type impurities such as phosphorus (P) is formed on the semiconductor layer 42. The ohmic contacts 55 and 56 may be formed on both sides of the gate electrode 25.

On the ohmic contacts 55 and 56, data lines 62, 65 and 66 made of a metal or a conductor such as aluminum or an aluminum alloy, molybdenum or molybdenum-tungsten alloy, chromium and tantalum are formed. The data line extends in the vertical direction and faces the source electrode 65 centering on the data line 62 to which an image signal is applied from the outside, the source electrode 65 which is a part of the data line 62, and the gate electrode 25. And a drain electrode 66.

The data lines 62, 65, and 66 may be formed in a single layer like the gate lines 22 and 26, but may be formed in a double layer or a triple layer. In the case of forming more than two layers, it is preferable that one layer is formed of a material having a low resistance and the other layer is formed of a material having good contact properties with other materials.

A protective film 90 made of silicon nitride is formed on the data lines 62, 65, 66 and the gate insulating film 30. The protective film 90 has a contact hole 92 exposing the drain electrode 66.

On the passivation layer 90, a pixel electrode 102 made of a transparent conductive film such as indium tin oxide (ITO) or indium zinc oxide (IZO) is formed in a pixel area divided into a gate line and a data line.

The pixel electrode 102 is connected to the drain electrode 66 through the contact hole 92 to receive an image signal.

Next, the structure of the "upper board | substrate" for liquid crystal display devices which opposes the "lower board | substrate" for liquid crystal display devices which have such a structure is demonstrated.

1 and 2, the upper substrate corresponds to a pixel region in the form of a matrix defined by the intersection of the gate line 22 and the data line 62 in the "lower substrate" on a transparent insulating substrate 100 such as glass. The color filters 200 of red (R), green (G), and blue (B) are sequentially arranged. In this case, in the color filters 200 sequentially arranged for each pixel region, the color filters 200 and the edges of neighboring pixel regions overlap with each other. This is to block unnecessarily leakage of light between the pixels. In this way, the black matrix may not be separately formed at the overlapped portion of the color filter 200.

That is, since two edge portions of neighboring color filters 200 overlap each other, the color filter 200 absorbs or blocks most of the light passing through the portions because the two colors overlap each other. Can function as

Here, the color filter 200 is linearly formed for each pixel column, but may not be.

In addition, a planarization passivation layer 300 is formed on the substrate to cover the color filter 200, and the color filter 200 protrudes from the non-overlapping portion between pixel regions where the color filter 200 is overlapped to form a passivation layer ( A pillar spacer 350 made of the same material as 300 is formed.

Specifically, a passivation layer 300 is formed on the color filter 200 to planarize the entire layer of the color filter 200. An upper portion of the pixel boundary where the color filter 200 overlaps is formed as the passivation layer 300. The pillar spacer 350 is formed of a material. In this case, the column spacer 350 is linearly formed along the overlapped portion of the color filter 200. In the embodiment of the present invention, the pillar spacer 350 is formed in a linear shape, but may be formed in a dot shape at regular intervals.

Here, it is preferable that the thickness of a protective film is formed in 0.8 micrometer-1.5 micrometers, and the pillar spacer is formed in the thickness of 2.5 micrometers-3.5 micrometers.

A common electrode 400 made of a transparent conductive film such as ITO or IZO is formed on the passivation layer 300 and the pillar spacer 350.

On the other hand, although not shown in the embodiment of the present invention, the opening pattern or the projection pattern is formed in the common electrode 400 of the "upper substrate", and the opening pattern or the projection pattern is also formed in the pixel electrode 102 of the "lower substrate". It is preferable that it is formed. The liquid crystal is aligned in the vertical direction between the “upper substrate” and the “lower substrate”, and the opening pattern or the projection pattern serves to control the inclination of the liquid crystal oriented in the vertical direction to implement a wide viewing angle.

In addition, the liquid crystal is twisted and aligned, and the twist angle may have a value between 80 ° and 100 °, or a value between 250 ° and 300 °.

Next, a method of manufacturing a color filter substrate of a liquid crystal display according to an exemplary embodiment of the present invention will be described with reference to FIGS. 3 to 4.

3 is a view showing a cross section of the color filter substrate in the first step of manufacturing a color filter substrate for a liquid crystal display device according to an embodiment of the present invention, Figure 4 is a cross-sectional view of the color filter substrate in the next step of FIG. 5 is a diagram showing a cross section of the completed color filter substrate.

As shown in FIG. 3, the color filter 200 is formed on the transparent substrate 100 made of glass or the like.

The process of forming the color filter 200 is as follows.

First, a red photosensitive organic film for forming a red filter is coated on the transparent substrate 100, and then exposed and developed using a mask to form a red filter R.

Next, a green photosensitive organic film is coated on the entire surface of the substrate on which the red filter R is formed, and the green filter G is formed by a photographic process using a mask.

Next, a blue photosensitive organic film is coated on the entire surface of the substrate on which the red and green filters R and G are formed to form a blue filter B by a photo process using a mask.

As described above, the color filter 200 arranges the red (R), green (G), and blue (B) color filters 200 in sequence for each pixel column. In this case, the neighboring color filters of each pixel column ( Both ends of 200) overlap each other. Therefore, since the color filter 200 formed by overlapping both ends at the boundary portion of each pixel column prevents light transmission, it is not necessary to form a black matrix separately.

Next, as shown in FIG. 4, the passivation layer 300 and the pillar spacer 350 are formed on the color filter 200.

Specifically, the polymer material which is a negative or positive photosensitive resin is laminated, and the protective film 300 and the pillar spacers 350 are simultaneously formed in one photo process using one mask.

At this time, both ends of the color filter are overlapped to form the pillar spacer 350 in the protruding portion, and the remaining passivation layer 300 is formed to be flat.

As described above, the passivation layer 300 and the pillar spacers 350 having partially different thicknesses are simultaneously formed using masks having partially different transmittances. The principle is as follows.

In order to control the light transmission, a slit or lattice pattern or a mask with a translucent film is used. In this case, the line width of the pattern or the interval between the patterns, that is, the width of the slit, is preferably smaller than the resolution of the exposure machine used for exposure. A thin film having a thickness or a thin film may be used.

When the photoresist is irradiated with light through such a mask, when the photoresist is positive, the polymers are completely decomposed at the portion directly exposed to the light, and the amount of light is less at the portion corresponding to the slit pattern or the translucent film. Therefore, the polymers are not completely decomposed, and the polymers are hardly decomposed at the part covered by the light shielding film.

When developing the photosensitive resin selectively exposed in this manner, only the portions where the polymers are not decomposed remain, and the photosensitive resin having a thickness thinner than the portion not irradiated with light is left in the portion where the light is not irradiated.

As for the thickness of the protective film 300 and the pillar spacer 350 formed by such a method, 1 micrometer and 3 micrometers are preferable, respectively.

Finally, as shown in FIG. 5, the common electrode is formed of a transparent conductive film such as ITO or IZO to complete the color filter substrate.

Accordingly, the protective film 300 and the pillar spacer 350 of the same material may be simultaneously formed using a mask having a partially different transmittance, thereby simplifying the process.

As in the present invention, it is possible to minimize the occurrence of stains by maintaining a constant cell gap with the column spacer, and also to reduce the process by forming a protective film and the column spacer for the flattening of the color filter as one mask at the same time, Productivity can be increased.

Claims (15)

First insulating substrate, A second insulating substrate having an inner surface facing the inner surface of the first substrate and coupled to the first substrate, A plurality of wirings formed on an inner surface of the first substrate and partitioning pixel regions in a matrix form; A plurality of switching elements formed on an inner surface of the first substrate and connected to the wires; A plurality of pixel electrodes formed on an inner surface of the first substrate and connected to the switching elements; A color filter sequentially formed on an inner surface of the second substrate of the pixel region; A protective film covering and covering the color filter on the inner surface of the second substrate, A plurality of pillar spacers formed integrally with the passivation layer and disposed between the pixel areas and formed to a thickness thicker than the passivation layer to support the gap between the first and second substrates. Liquid crystal display comprising a. In claim 1, And a common electrode formed on the passivation layer on the inner surface of the second substrate. In claim 2, The pixel electrode and the common electrode have an opening or a projection pattern formed therein. In claim 1, And a liquid crystal circulated in the vertical direction between the first and second substrates. In claim 1, The liquid crystal display further comprises a liquid crystal between the first and second substrates, wherein the liquid crystal is twisted and oriented between the upper and lower substrates, and the twist angle is between 80 ° and 100 °. In claim 1, The liquid crystal display further comprises a liquid crystal between the first and second substrates, wherein the liquid crystal is twisted and oriented between the upper and lower substrates, and the twist angle is between 250 ° and 300 °. Insulation board, A color filter formed on an inner surface of the insulating substrate, A protective film covering and covering the color filter on the inner surface of the insulating substrate, Is formed integrally with the protective film, a plurality of pillar spacers formed of a thicker than the protective film, A common electrode formed entirely on the passivation layer and the pillar spacer; Color filter substrate comprising a. In claim 7, In the color filter, red (R), green (G), and blue (B) color filters are sequentially arranged for each pixel column of a plurality of pixel regions, and both ends of the color filter are each adjacent to each of the neighboring pixel columns. Color filter substrate formed by overlapping. In claim 8, And a column spacer formed of the same material as the passivation layer on an upper portion of the overlapping both ends of the color filter. The method of claim 7 or 9, The pillar spacers are linearly formed. The method according to any one of claims 7, 9 and 10, The thickness of the protective film is 0.8㎛ ~ 1.5㎛, the thickness of the pillar spacer is 2.5㎛ ~ 3.5㎛ formed color filter substrate. In the manufacturing method of the color filter substrate for liquid crystal display devices, Forming a color filter on the transparent substrate; Forming a protective layer and a pillar spacer on the color filter; Forming a common electrode formed of a transparent conductive material on the passivation layer and the pillar spacer; And said protective film and said pillar spacer are formed simultaneously using a mask having a partially different transmittance. In claim 12, The protective film and the pillar spacers are formed using a negative or positive photosensitive resin. In claim 12, The color filter is a stripe-shaped red (R), green (G), blue (B) color filters are arranged in sequence, and both ends of the color filter is formed by overlapping each other. The method of claim 14, The pillar spacer is formed on the upper portion of the overlapping both ends of the color filter manufacturing method of the color filter substrate.