KR100989465B1 - Device and fabrication method for liquid crystal display - Google Patents

Abstract

The present invention relates to a liquid crystal display and a method of manufacturing the same. A liquid crystal display device according to the present invention comprises: a switching element formed in a switching area of a substrate having a switching area and a pixel area; A barrier rib patterned after the organic insulating film is applied to the pixel area on the substrate on which the switching element is formed, and spaced at a predetermined interval; Concave-convex irregularities formed between the partition walls spaced apart from the predetermined intervals; It is characterized in that it comprises a reflective plate formed by depositing a metal material on the partition and concave-convex concave-convex.

In the liquid crystal display device and the manufacturing method thereof according to the present invention, by forming a reflective plate applied to the reflective liquid crystal display device in a concave-convex concave-convex structure, it is possible to minimize the planar components and increase the density.

Reflective electrode, bulkhead, inkjet, concave and convex

Description

Liquid crystal display and its manufacturing method {DEVICE AND FABRICATION METHOD FOR LIQUID CRYSTAL DISPLAY}

1 is a plan view of an array substrate corresponding to one pixel of a typical reflective liquid crystal display device.

FIG. 2 is a cross-sectional view illustrating an array substrate and a color filter substrate corresponding thereto cut along the line II ′ of FIG. 1 according to the related art. FIG.

3A to 3F are flowcharts illustrating a method of manufacturing an array substrate of a reflective liquid crystal display device according to the related art.

4 is a schematic cross-sectional view of a reflective liquid crystal display device according to the present invention;

5 is a view showing a process in which light proceeds by the irregularities of the concave reflector according to the present invention.

Fig. 6 is a diagram showing the reflection density within the effective reflection angle of the reflection plate.

7A to 7E are flowcharts illustrating a method of manufacturing a reflective liquid crystal display device according to the present invention.

<Description of the symbols for the main parts of the drawings>

48 --- Reflective electrode 71 --- Organic insulating film                 

72 --- bulkhead 73 --- ink

51 --- First substrate 52 --- Reflective electrode

53 --- liquid crystal layer 54 --- second substrate

55 --- air layer

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device and a method for manufacturing the same, and more particularly, to a liquid crystal display device and a method for manufacturing the same, by forming a reflecting plate applied to a reflective liquid crystal display device in a concave-convex structure to minimize the flatness. will be.

Recently, with the rapid development of the information society, the necessity of a flat panel display having excellent characteristics such as thinning, light weight, and low power consumption has emerged.

Such a flat panel display can be divided according to whether it emits light by itself or not. A light emitting display device that emits light by itself is called a light emitting display device. It is called a display device. The light emitting display includes a plasma display panel, a field emission display, an electroluminescence display, and the light receiving display includes a liquid crystal display. There is).                         

Among them, liquid crystal display devices are being actively applied to notebooks and desktop monitors because of their excellent resolution, color display, and image quality.

In general, a liquid crystal display 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 voltage to the two electrodes. By moving the liquid crystal molecules by the electric field to be adjusted, thereby adjusting the transmittance of the light is changed to represent the image.

However, the liquid crystal display device does not emit light as described above, so a separate light source is required.

Therefore, an image is displayed by arranging a backlight on the back of the liquid crystal panel and injecting light from the backlight into the liquid crystal panel to adjust the amount of light according to the arrangement of the liquid crystals. In this case, the field generating electrode of the liquid crystal display device is made of a transparent conductive material, and both substrates should also be made of a transparent substrate.

Such a liquid crystal display device is called a transmission type liquid crystal display device. Since the liquid crystal display device uses an artificial back light source such as a backlight, it can realize a bright image even in a dark external environment, but power consumption due to the backlight is high. There is a big disadvantage.

In order to compensate for the above disadvantages, a reflection type liquid crystal display device has been proposed. The reflection type liquid crystal display device has less power consumption than the transmission type liquid crystal display device in the form of controlling light transmittance according to the arrangement of liquid crystals by reflecting external natural light or artificial light. In the reflective LCD, the lower field generating electrode is formed of a conductive material that reflects well, and the upper field generating electrode is formed of a transparent conductive material to transmit external light.

Hereinafter, a reflection type liquid crystal display device will be described as an example of a liquid crystal display device having a reflection plate with reference to the accompanying drawings.

1 is a plan view of an array substrate corresponding to one pixel of a typical reflective liquid crystal display device. As shown in the drawing, the gate wiring 8 arranged in a row on the substrate and the data wiring 2 arranged in a column form one pixel.

The gate electrode 12 is positioned at a predetermined position of the gate wiring 8, and the source electrode 16b is overlapped with a predetermined length on the gate electrode 12 in the data wiring. It is.

In addition, a drain electrode 16c is formed to correspond to the source electrode 16b and the reflective electrode 18 is formed through a drain contact hole 17a disposed on the drain electrode 16c. The drain electrode 16c is in electrical contact with the drain electrode 16c. In general, the reflective electrode 18 is made of a metal having excellent reflectance.

2 is a cross-sectional view of an array substrate cut along the line II ′ of FIG. 1 and a color filter substrate corresponding thereto.

As shown in this figure, the 1st board | substrate 11 and the 2nd board | substrate 21 are arrange | positioned at predetermined intervals. A gate electrode 12 is formed on the lower first substrate 11, and a gate insulating layer 13 is formed thereon.                         

A gate line (8 of FIG. 1) connected to the gate electrode 12 is further formed under the gate insulating layer 13. Next, the active layer 14 and the ohmic contact layers 15a and 15b are sequentially formed on the gate insulating layer 13 on the gate electrode 12. Source and drain electrodes 16b and 16c are formed on the ohmic contact layers 15a and 15b, and the source and drain electrodes 16b and 16c form a thin film transistor T together with the gate electrode 12. .

Meanwhile, a data line 4 made of the same material as the source and drain electrodes 16b and 16c is formed on the gate insulating layer 13, and the data line 4 is connected to the source electrode 16b. have. In this case, the data line 4 crosses the gate line to define a pixel area.

Next, a passivation layer 17 made of an organic material is formed on the data line 4 and the source and drain electrodes 16b and 16c to cover a thin film transistor (T). 17 has a contact hole 17a exposing the drain electrode 16c.

Subsequently, a reflective electrode 18 is formed in the pixel area above the passivation layer 17 and connected to the drain electrode 16c through the contact hole 17a. The reflective electrode 18 is made of a conductive material such as metal and covers the thin film transistor T. In addition, the aperture ratio can be improved by overlapping with the data line 4. The protective layer 17 is formed of an organic material having a low dielectric constant, and is formed between the reflective electrode 18 and the data line 4. Do not cause signal interference.                         

On the other hand, a black matrix 22 is formed on the inner surface of the second substrate 21, and a color filter in which red (R), green (G), and blue (B) are sequentially repeated at the bottom thereof ( 23a, 23b, and 23c are formed, and a common electrode 24 made of a transparent conductive material is formed under the color filters 23a, 23b, and 23c. Here, the color filters 23a, 23b, and 23c have one color corresponding to one reflective electrode 18, and the black matrix 22 is formed at a position corresponding to an edge of the reflective electrode 18. have.

As mentioned above, since the reflective electrode 18 made of an opaque conductive material such as metal covers the thin film transistor T, the black matrix 22 may be formed to cover only the edge of the reflective electrode 18. have.

Next, the liquid crystal layer 30 is positioned between the reflective electrode 18 and the common electrode 24, and the liquid crystal molecules of the liquid crystal layer 30 are disposed on the reflective electrode 18 and the common electrode 24. When a voltage is applied, the arrangement state is changed by the electric field generated between the two electrodes 18, 24. Although not illustrated, an alignment layer is formed on the reflective electrode 18 and the common electrode 24, respectively, to determine the initial arrangement state of the liquid crystal molecules.

Meanwhile, referring to a cross-sectional view of an array substrate for a reflective liquid crystal display device including the uneven reflection plate of FIG. I will describe.

3A to 3F are flowcharts illustrating a method of manufacturing an array substrate of a reflective liquid crystal display device according to the related art. Here, the process of forming the source / drain electrodes is the same as in the conventional liquid crystal display device, and thus will be omitted.                         

First, as illustrated in FIG. 3A, an organic material is coated on the passivation layer 17 to form a first organic layer 31. This organic material is preferably made of a photosensitive material. This is because there is no need to use a separate photoresist to pattern the organic material.

Subsequently, as shown in FIG. 3B, when exposed and developed using a mask, and the photosensitive organic material is removed, the sawtooth-shaped organic film pattern 33 having a predetermined interval and size can be formed. At this time, it is possible to adjust the inclination angle of the irregularities to be formed later by adjusting the interval and the degree of overlap between the patterns. Such organic materials may cause the portions that are not illuminated to be removed or may be such that the portions that are not illuminated are removed.

Next, as shown in FIG. 3C, when the tooth-shaped first organic film pattern 33 is heat-treated, an uneven second organic film pattern 35 is formed. At this time, the organic layer pattern is melted and spread by heat treatment, and then cured to form a gentle bend having an inclination angle of about 10 degrees.

Subsequently, as illustrated in FIG. 3D, an organic material is coated on the entire surface of the protective layer on which the uneven second organic film pattern 35 is formed to form the second organic film 37. Here, the second organic film 37 adjusts the contour formed by the uneven second organic film pattern 35 to form a curved surface having an inclination angle of about 10 degrees.

Next, as shown in FIG. 3E, the drain contact hole exposing the drain electrode 16c by patterning the passivation layer 17 including the first organic layer 35 and the second organic layer 37. It forms 17a.                         

Finally, as shown in FIG. 3F, a reflective electrode 18 is formed in the pixel area on the passivation layer 17 to reflect light using a mask.

On the other hand, the manufacturing method of the array substrate for a reflective transmissive liquid crystal display device is the same as the manufacturing method of the said array substrate for a reflective liquid crystal display device which forms the uneven | corrugated organic film pattern. However, a mask process for patterning the transparent electrode is further added.

As described above, when the reflective film having the micro-reflective plate structure (MRS) is formed in the reflective or reflective transmissive liquid crystal display device, a photo mask process for patterning the organic insulating film is additionally performed, resulting in a high production cost.

SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid crystal display device and a method of manufacturing the same, by forming a reflecting plate applied to a reflective liquid crystal display device in a concave and convex structure to minimize the planar components and increase the density.

In order to achieve the above object, the liquid crystal display device according to the present invention,

A switching element formed in the switching area of the substrate having the switching area and the pixel area;

A barrier rib patterned after the organic insulating film is applied to the pixel area on the substrate on which the switching element is formed, and spaced at a predetermined interval;

Concave-convex irregularities formed between the partition walls spaced apart from the predetermined intervals;

It is characterized in that it comprises a reflective plate formed by depositing a metal material on the partition and concave-convex concave-convex.                     

Here, in particular, the reflector is characterized in that it is formed as a concave reflector.

Here, in particular, the partition wall is characterized in that it has a semi-circle taper, a square taper or an inverted taper shape.

In addition, the manufacturing method of the liquid crystal display device according to the present invention in order to achieve the above object,

Forming a switching element in said switching region of the substrate having a switching region and a pixel region;

Forming an organic insulating film in the pixel region of the substrate;

Hardening the organic insulating film by patterning partition walls spaced apart from each other by a predetermined interval;

Dropping and curing the ink of the organic insulating film material between the barrier ribs;

It is characterized in that it comprises the step of depositing a metal material on the cured pattern.

Here, in particular, the partition is characterized in that it is formed in a semi-circle taper, square taper or inverse taper shape.

In particular, the ink jet method is applied as a method of dropping ink between the partition walls.

Here, in particular, the ink dropped between the barrier ribs is characterized in that it rises along the barrier ribs by a pinning phenomenon and a capillary phenomenon to form a concave shape.

According to the present invention, by forming the reflecting plate applied to the reflective liquid crystal display device in the concave-convex structure, the compactness can be increased by minimizing the planar component.

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

4 is a schematic cross-sectional view of a reflective liquid crystal display device according to the present invention. 4 is a cross sectional view showing a color filter substrate corresponding to an array substrate cut along the line II ′ of FIG. 1, wherein the cross-sectional structure of the reflective liquid crystal display device shown in FIG. Since it is similar to FIG. 2, a detailed description thereof will be omitted.

As shown in FIG. 4, in the liquid crystal display according to the present invention, concave-shaped bends are formed on the upper surface of the protective layer 47 so that the surface of the reflective electrode 48 has an uneven shape. Therefore, the front brightness can be improved by changing the angle of the reflected light.

5 is a diagram showing the reflection density within the effective reflection angle of the reflecting plate. As shown therein, A represents the reflection density within the effective reflection angle of the reflecting plate having the convex concave-convex structure according to the prior art, and B represents the reflection density within the effective reflection angle of the reflecting plate having the concave-convex concave-convex structure according to the present invention.

Therefore, it can be seen that the reflecting plate having the concave-convex concave-convex structure according to the present invention has a high reflectance within the effective reflecting angle.

In addition, a method of manufacturing a reflective liquid crystal display device according to a preferred embodiment of the present invention will be described. 6A to 6E are flowcharts illustrating a method of manufacturing a reflective liquid crystal display device according to the present invention.                     

First, as shown in FIG. 6A, a gate electrode 42 is formed on the substrate 41. Here, a metal layer such as chromium, copper, aluminum is deposited on the substrate 41, the metal layer is cleaned, and a photoresist is coated thereon. Next, the gate pattern formed on the photomask is exposed on the photoresist, developed and etched, and then the photoresist is removed to form the gate electrode 42.

A gate insulating layer 43 is formed on the substrate 41 on which the gate electrode 42 is formed. At this time, a silicon nitride film (SiNx) or a silicon oxide film (SiO₂) is used as the gate insulating film 43.

Next, an active layer 44 of amorphous silicon and an ohmic contact layer 45a and 45b containing impurities are formed on the gate insulating layer 43 on the gate electrode 42. A semiconductor layer having an island shape is formed. Here, an active layer 44 is formed by depositing and patterning a silicon layer, and ohmic contact layers 45a and 45b are formed by ion doping with phosphorus or boron as impurities in the active layer.

Next, a data line 34 is formed on the ohmic contact layers 45a and 45b to vertically cross the source electrode 46b, the drain electrode 46c, and the gate line to define the pixel area P. . Here, metal layers are deposited and patterned to form source / drain electrodes 46b and 46c and data lines 34. Meanwhile, the active layer 44 and the ohmic contact layers 45a and 45b are formed, and source / drain electrodes 46b and 46c are formed thereon, and then exposed in a spaced apart area between the source / drain electrodes 46b and 46c. The ohmic contact layers 45a and 45b are removed to expose the active layer 44 at the bottom to form a channel region.

Next, a protective layer 47 is formed by depositing an insulating material on the substrate 41 on which the source / drain electrodes 46b and 46c are formed. At this time, the protective layer 47 is made of a silicon nitride film or a silicon oxide film, preferably an organic insulating film of benzocyclobutene (BCB) or photoacryl series.

Next, as illustrated in FIG. 6B, an organic material is coated on the passivation layer 47 to form an organic insulating layer 71.

Subsequently, as shown in FIG. 6C, the organic insulating layer 71 forms a barrier 72 by using a photo process.

At this time, the organic insulating film pattern of the partition 72 is cured to a desired texture through a heat treatment process. Therefore, the partition wall 72 may be formed in various shapes such as a semi-circle taper, a square taper, or an inverse taper shape by a photo process.

Next, as shown in FIG. 6D, the ink 73, which is a material of an organic insulating material, is dropped like a drop of water between the formed partitions 72 using an ink jet method.

At this time, the ink 73 dropped in the partition wall 72 is not formed flat due to pinning and capillary phenomenon, and rises along the partition 72 to form a concave shape.

The ink 73 of the organic insulating material formed in a concave shape between the partitions 72 is cured.

Subsequently, as shown in Fig. 6E, a reflective electrode 48 for reflecting light in the pixel region is formed on the entire surface of the concave organic film pattern.

The reflective electrode 48 is made of a conductive material such as aluminum or an aluminum alloy, which reflects light well.

Although the present invention has been described with reference to the embodiments illustrated in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

As described above, the liquid crystal display device and the method of manufacturing the same according to the present invention can increase the compactness by minimizing the planar components by forming the reflective plate applied to the reflective liquid crystal display device in a concave-convex structure.

In addition, in forming the concave reflecting plate, the number of processes can be reduced by applying an ink jet method.

Claims (7)

A switching element formed in the switching area of the substrate having the switching area and the pixel area; A barrier rib patterned after the organic insulating film is applied to the pixel area on the substrate on which the switching element is formed, and spaced at a predetermined interval; Concave-convex irregularities formed between the partition walls spaced apart from the predetermined intervals; And a reflector formed by depositing a metal material on the barrier ribs and the concave-convex concave-convex. The method of claim 1, And the reflector is formed as a concave reflector. The method of claim 1, And the partition wall has a semi-circle taper, a square taper or an inverted taper shape. Forming a switching element in said switching region of the substrate having a switching region and a pixel region; Forming an organic insulating film in the pixel region of the substrate; Hardening the organic insulating film by patterning partition walls spaced apart from each other by a predetermined interval; Dropping and curing the ink of the organic insulating film material between the barrier ribs; And depositing a metal material on the cured pattern. The method of claim 4, wherein And the partition wall is formed in a semi-circle taper, a square taper or an inverted taper shape. The method of claim 4, wherein And the ink jet method is applied to the ink dropped between the barrier ribs. The method of claim 4, wherein And the ink dropped between the partition walls is formed along the partition walls by a pinning phenomenon and a capillary phenomenon to form a concave shape.

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