KR20040110932A - Liquid Crystal Display Panel and Fabricating Method Thereof - Google Patents

Abstract

PURPOSE: An LCD(Liquid Crystal Display) and a method for manufacturing the same are provided to enhance adhesive strength between a common electrode and a dotting, thereby reducing resistance between the common electrode and the dotting and applying a common voltage securely by forming the common electrode to have a convex-concave surface. CONSTITUTION: An LCD comprises an upper substrate(92), a lower substrate(51) and a liquid crystal layer between the upper substrate and the lower substrate. A convex-concave pattern(97) is formed on the upper substrate and a common electrode(98) is formed on the convex-concave pattern, thereby having a convex-concave surface. A signal electrode(82) for applying a driving signal to the common electrode is formed on the lower substrate. A dotting formed of Ag(88) is formed to connect the signal electrode and the common electrode. The convex-concave surface of the common electrode widens the contact area between the common electrode and the dotting, thereby enhancing adhesive strength between the common electrode and the dotting.

Description

Liquid Crystal Display Panel and Fabrication Method Thereof}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display panel, and more particularly, to a liquid crystal display panel and a manufacturing method thereof capable of preventing a deterioration in image quality.

Conventional liquid crystal display devices display an image by adjusting the light transmittance of the liquid crystal using an electric field. To this end, the liquid crystal display device includes a liquid crystal display panel in which liquid crystal cells are arranged in a matrix, and a driving circuit for driving the liquid crystal display panel. The liquid crystal display panel is provided with pixel electrodes and a common electrode for applying an electric field to each of the liquid crystal cells. In general, the pixel electrode is formed for each liquid crystal cell on the lower substrate, while the common electrode is integrally formed on the front surface of the upper substrate. Each of the pixel electrodes is connected to a thin film transistor (TFT) used as a switch element. The pixel electrode drives the liquid crystal cell along with the common electrode according to the data signal supplied through the thin film transistor.

1 is a diagram illustrating a liquid crystal display panel which is commonly used.

Referring to FIG. 1, a conventional liquid crystal display panel includes an upper substrate 42 and a lower substrate 1 facing each other.

In the display area of the lower substrate 1, a TFT and a pixel electrode 22 connected to the TFT are formed. The black matrix 44, the color filter 46, and the common electrode 48 are formed in the display area of the upper substrate 42. Liquid crystal is injected between the lower substrate 1 and the upper substrate 42 of the display area.

The TFT is connected to the gate electrode 6 connected to the gate line (not shown), the source electrode 8 connected to the data line (not shown), and the drain connected to the pixel electrode 22 through the first contact hole 26. An electrode 10 is provided. Further, the TFT further includes semiconductor layers 14 and 16 for forming a conduction channel between the source electrode 8 and the drain electrode 10 by the gate voltage supplied to the gate electrode 6. The TFT selectively supplies the data signal from the data line (not shown) to the pixel electrode 22 in response to the gate signal from the gate line (not shown).

The pixel electrode 22 is formed in a cell region divided by a data line (not shown) and a gate line (not shown) and is made of a transparent conductive material having high light transmittance. The pixel electrode 22 is formed on the passivation layer 18 coated on the entire surface of the substrate 1 and electrically connected to the drain electrode 10 through the first contact hole 26 penetrating the passivation layer 18. The pixel electrode 22 generates a potential difference from the common electrode 48 formed on the upper substrate 42 by the data signal supplied via the TFT. Due to this potential difference, the liquid crystal positioned between the lower substrate 1 and the upper substrate 42 rotates due to the dielectric anisotropy. The amount of light transmitted from the light source to the upper substrate 42 through the pixel electrode 22 is controlled by the rotated liquid crystal.

The black matrix 44 formed in the display area of the upper substrate 42 is formed between adjacent liquid crystal cells to absorb light incident on it.

The color filter 46 formed in the display area of the upper substrate 42 transmits any one of red, green, and blue light and absorbs light having a wavelength band other than that to display a desired color.

The common electrode 48 is applied with a common voltage to generate a potential difference with the pixel electrode 22 formed on the lower substrate 1.

The metal electrode 32 and the signal electrode 36 are formed in the non-display area of the lower substrate 1, and the black matrix 44 and the common electrode 48 are formed in the non-display area of the upper substrate 42.

Ag dotting 38 is formed between the signal electrode 36 formed on the lower substrate 1 of the non-display area and the common electrode 48 formed on the upper substrate 42. One side of the silver dot 38 is in contact with the signal electrode 36 formed on the lower substrate 1, and the other side is in contact with the common electrode 48 formed on the upper substrate 42. The common voltage supplied to the 32 is supplied to the common electrode 48 through the signal electrode 36 and the silver clay 38.

In this case, the signal electrode 36 in contact with one side of the silver dot 38 is electrically connected to the metal electrode 32 through the plurality of second contact holes 34 passing through the passivation layer 18. The signal electrode 36 is designed in a concave-convex shape to increase the adhesive force with the silver dot 38 to reduce the common voltage contact resistance. Accordingly, the common voltage can be supplied stably.

However, since the common electrode 48 in contact with the other side of the silver dot 38 is designed in a flat shape, the adhesive force with the silver dot 38 is relatively weak, thereby increasing the common voltage contact resistance. In other words, since the contact area between the common electrode 48 formed on the upper substrate 42 and the silver dot 38 is narrow, the common voltage contact resistance is supplied when the common voltage is supplied to the common electrode 48 through the silver dot 38. Will increase. Accordingly, since the common voltage cannot be stably supplied, there is a problem of degrading the image quality.

Accordingly, it is an object of the present invention to provide a liquid crystal display panel and a manufacturing method thereof capable of preventing the deterioration of image quality.

1 is a cross-sectional view showing a conventional liquid crystal display panel.

2 is a cross-sectional view illustrating a liquid crystal display panel according to an exemplary embodiment of the present invention.

3A to 3D are cross-sectional views illustrating a method of manufacturing the liquid crystal display panel illustrated in FIG. 2.

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

1,51: Lower board 42,92: Upper board

6,56 gate electrode 8.58 source electrode

10,60 drain electrode 12,62 gate insulating film

14,64: active layer 16,66: ohmic contact layer

18,68 protective film 22,72 pixel electrode

26,76: first contact hole 32,82: metal electrode

34,84: second contact hole 36,86: signal electrode

38,88: Silver Dot 44,94: Black Matrix

46,96: color filter 48,98: transparent common electrode

97: color pattern 100: hole

In order to achieve the above object, a liquid crystal display panel according to an embodiment of the present invention is a concave-convex pattern formed on a portion of the upper substrate, a common electrode formed in the concave-convex shape along the concave-convex pattern on the concave-convex pattern, And a dot pattern formed on the lower substrate facing the substrate to connect the common electrode with a signal electrode for supplying a driving signal to the common electrode.

The liquid crystal display panel further includes a black matrix formed on the upper substrate so as to overlap the uneven pattern, and a color filter formed in the pixel region provided by the black matrix.

In the liquid crystal display panel, the uneven pattern is made of the same material as the color filter and is disposed on the same plane as the color filter.

The liquid crystal display panel further includes a protective film having a concave-convex shape formed on a lower substrate and including a metal electrode for supplying the driving signal to the signal electrode, and a plurality of contact holes for connecting the metal electrode and the signal electrode. .

In the liquid crystal display panel, the signal electrode may be formed in an uneven shape along the protective film on the uneven protective film.

The method of manufacturing a liquid crystal display panel according to an embodiment of the present invention comprises the steps of forming the uneven patterns on a specific region of the upper substrate, and forming a common electrode of the uneven shape formed along the uneven pattern on the uneven pattern; And connecting a common electrode and a signal electrode formed on the lower substrate facing the upper substrate through a dot pattern.

The manufacturing method of the liquid crystal display panel further includes forming a black matrix on the upper substrate so as to overlap the uneven pattern, and forming a color filter in the pixel region provided by the black matrix.

In the manufacturing method of the liquid crystal display panel, the uneven pattern may be positioned on the same plane as the color filter and the same material as the color filter.

The manufacturing method of the liquid crystal display panel includes forming a metal electrode for supplying a driving signal to the signal electrode formed on the lower substrate, and an uneven protective film including a plurality of contact holes for connecting the metal electrode and the signal electrode. It further comprises forming a.

In the method of manufacturing the liquid crystal display panel, the signal electrode may be formed in an uneven shape along the protective film on the uneven protective film.

Other objects and features of the present invention in addition to the above object will become apparent from the description of the accompanying examples.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 2 to 3D.

2 illustrates a liquid crystal display panel according to an exemplary embodiment of the present invention.

Referring to FIG. 2, the liquid crystal display panel of the present invention is divided into a display area in which a liquid crystal cell matrix is positioned and a non-display area located in an outer portion of the display area.

On the lower substrate 51 of the display area, a TFT and a pixel electrode 72 connected to the TFT are formed. The black matrix 94, the color filter 96, and the common electrode 98 are formed on the upper substrate 92 of the display area. Liquid crystal is injected between the lower substrate 51 and the upper substrate 92 of the display area.

The TFT includes a gate electrode 56 connected to the gate line, a source electrode 58 connected to the data line, and a drain electrode 60 connected to the pixel electrode 72 through the first contact hole 76. In addition, the TFT further includes semiconductor layers 64 and 66 for forming a conductive channel between the source electrode 58 and the drain electrode 60 by the gate voltage supplied to the gate electrode 56. This TFT selectively supplies the data signal from the data line to the pixel electrode 72 in response to the gate signal from the gate line.

The pixel electrode 72 is positioned in a cell region divided by a data line and a gate line and is made of a transparent conductive material having high light transmittance. The pixel electrode 72 is formed on the passivation layer 68 coated on the entire surface of the substrate 51 and is electrically connected to the drain electrode 60 through the first contact hole 76 passing through the passivation layer 68. The pixel electrode 72 generates a potential difference from the common transparent electrode 98 formed on the upper substrate 92 by the data signal supplied through the TFT. Due to this potential difference, the liquid crystal positioned between the lower substrate 51 and the upper substrate 92 rotates due to the dielectric anisotropy. The amount of light transmitted from the light source to the upper substrate 92 through the pixel electrode 72 is adjusted by the rotated liquid crystal.

The black matrix 94 is formed between adjacent liquid crystal cells to absorb light incident on it.

The color filter 96 transmits any one of red, green, and blue light and absorbs light having a wavelength band other than that to display a desired color.

The common electrode 98 is applied with a common voltage to generate a potential difference with the pixel electrode 72 formed on the lower substrate 51. The common electrode 98 is formed of Indium-Tin-Oxide (ITO).

The metal electrode 82 and the signal electrode 86 are formed on the lower substrate 51 of the non-display area, and the black matrix 94, the color pattern 97, and the common electrode 98 are formed on the upper substrate 92. do. Here, the signal electrode 86 is formed of indium tin oxide (ITO).

Silver dots (Ag dots) 88 are formed between the signal electrode 86 formed on the lower substrate 51 of the non-display area and the common electrode 98 formed on the upper substrate 92. One side of the silver dot 88 is in contact with the signal electrode 86 formed on the lower substrate 51, and the other side is in contact with the common electrode 98 formed on the upper substrate 92. The common voltage supplied to 82 is supplied to the common electrode 98 through the signal electrode 86 and the silver clay 88.

At this time, the signal electrode 86 in contact with one side of the silver dot 88 is electrically connected to the metal electrode 82 through a plurality of second contact holes 84 passing through the passivation layer 68. The signal electrode 86 is formed in the uneven shape on the protective film 68 formed in the uneven shape by the plurality of second contact holes 84 to increase the adhesive force with the silver dot 88 to reduce the common voltage contact resistance. Let's go. Accordingly, the common voltage can be supplied stably. The common electrode 98 in contact with the other side of the silver dot 88 may include a plurality of color patterns 97 and a plurality of colors formed in the non-display area on the upper substrate 92 on which the black matrix 94 is formed. It is formed to overlap on the plurality of holes 100 between the patterns 97. That is, the common electrode 98 is formed in the form of irregularities in the non-display area on the upper substrate 92. Accordingly, the common electrode 92 increases the adhesive force with the silver dot 88 to reduce the common voltage contact resistance. In other words, since the common electrode 98 formed on the upper substrate 92 is formed in an uneven form, the contact area with the silver dot 88 is widened, so that the common voltage is applied to the common electrode 98 through the silver dot 88. When supplied, the common voltage contact resistance is reduced. Therefore, since the common voltage can be stably supplied, it is possible to prevent deterioration in image quality.

A method of manufacturing the liquid crystal display panel will be described with reference to FIGS. 3A to 3D.

Referring to FIG. 3A, a black matrix 94 is formed by depositing an opaque metal or an opaque resin on the upper substrate 92 and patterning the same by a photolithography process and an etching process. In the black matrix 94, portions corresponding to the pixel electrodes 72 of the lower substrate 51 are removed to block light.

Referring to FIG. 3B, after the color filter material is coated on the upper substrate 92, the material for the color filter is patterned by a photolithography process and an etching process using a mask, thereby forming a color filter 96 and a plurality of colors. Patterns 97 are formed. In this case, the plurality of color patterns 97 are formed to overlap the black matrix 94 of the non-display area of the liquid crystal display panel, and the color filter 96 is disposed between the black matrix 94 of the display area of the liquid crystal display panel. Is formed.

Referring to FIG. 3C, the common electrode 98 is formed by depositing a transparent conductive material on the upper substrate 92 on which the plurality of color patterns 97 and the color filter 96 are formed. In this case, the common electrode 98 formed in the non-display area of the upper substrate 92 is formed in a concave-convex shape by a plurality of holes 100 formed between the plurality of color patterns 97.

Referring to FIG. 3D, the upper substrate 92 on which the common electrode 98 is formed is bonded to the lower substrate 51 formed in advance. Accordingly, the common electrode 98 and the signal electrode 86 are electrically connected through the silver dot 88 so that the common voltage supplied through the signal electrode 86 may be supplied to the common electrode 98 through the silver dot 88. Supplied to. At this time, the signal electrode 86 formed in the non-display area of the lower substrate 51 is formed in the uneven shape, and the transparent common electrode 98 formed in the non-display area of the upper substrate 92 is formed in the uneven shape. have. That is, since the common electrode 98 and the signal electrode 86 are formed in the uneven form, the adhesive force with the silver dot 88 is relatively improved, thereby reducing the common voltage contact resistance. In other words, since the common electrode 98 formed on the upper substrate 92 is formed in an uneven form, the contact area with the silver dot 88 is widened, so that the common voltage is applied to the common electrode 98 through the silver dot 88. When supplied, the common voltage contact resistance is reduced. Therefore, since the common voltage can be stably supplied, it is possible to prevent deterioration in image quality.

As described above, according to the liquid crystal display panel and the method of manufacturing the same according to the embodiment of the present invention, the signal electrode formed in the non-display area of the lower substrate is formed in the form of irregularities, and is formed in the non-display area of the upper substrate. The electrode is formed into an uneven shape. Accordingly, when the silver dot is formed between the signal electrode and the common electrode, the adhesion between the two electrodes and the silver dot is improved to reduce the common voltage contact resistance, thereby stably supplying the common voltage, thereby preventing deterioration in image quality.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (10)

An uneven pattern formed on a portion of the upper substrate; A common electrode formed on the uneven pattern along the uneven pattern in the uneven form; And a dot pattern formed on the lower substrate facing the upper substrate, the signal electrode supplying a driving signal to the common electrode, and a dot pattern for connecting the common electrode. The method of claim 1, A black matrix formed on the upper substrate so as to overlap the uneven pattern; And a color filter formed in the pixel region provided by the black matrix. The method of claim 2, The uneven pattern is the same material as the color filter and the liquid crystal display panel, characterized in that located on the same plane as the color filter. The method of claim 1, A metal electrode formed on the lower substrate to supply the driving signal to the signal electrode; And an uneven protective film including a plurality of contact holes for connecting the metal electrode and the signal electrode. The method of claim 4, wherein And the signal electrode is formed in a concave-convex shape along the protective film on the concave-convex protective film. Forming uneven patterns on a specific area of the upper substrate; Forming a common electrode having an uneven shape formed on the uneven pattern along the uneven pattern; And connecting a signal electrode formed on the common electrode and a lower substrate facing the upper substrate through a dot pattern. The method of claim 6, Forming a black matrix on the upper substrate so as to overlap the concave-convex pattern; And forming a color filter in the pixel region provided by the black matrix. The method of claim 7, wherein And the concave-convex pattern is made of the same material as the color filter and is disposed on the same plane as the color filter. The method of claim 6, Forming a metal electrode for supplying a driving signal to the signal electrode formed on the lower substrate; And forming a protective film having a concave-convex shape including a plurality of contact holes for connecting the metal electrode and the signal electrode. The method of claim 9, And the signal electrode is formed in a concave-convex shape along the protective film on the concave-convex protective film.