KR100218503B1 - Liquid crystal display device and its manufacturing method - Google Patents

Abstract

The present invention relates to an active matrix substrate and a method of manufacturing the same, and more particularly, to an active matrix substrate constituting a liquid crystal display device and a method of manufacturing the same.

A plurality of gate lines and data lines defining pixel regions are formed to cross each other, and pixel electrodes partially overlapping the gate lines and data lines are formed in the pixel region around the edges.

A light blocking film is formed around the edge of the upper portion of the pixel electrode, and is connected to the gate line, and a branch of the gate line is formed at the edge of the pixel region in parallel with the data line.

Therefore, in the active matrix substrate and the manufacturing method thereof according to the present invention, the manufacturing process can be simplified by forming a light blocking film using a protective film as a mask without a separate photo etching process, and a light blocking film is formed around the pixel to form a light blocking effect. In addition, by forming the light blocking film as described above, the black matrix formed on the other substrate is formed to have a narrower width than in the prior art, thereby increasing the aperture ratio.

Description

Liquid Crystal Display and Manufacturing Method Thereof

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active matrix substrate and a method of manufacturing the same, and more particularly, to an active matrix substrate constituting a liquid crystal display device and a method of manufacturing the same.

Referring to the accompanying drawings, a conventional active matrix substrate and a manufacturing method thereof will be described in more detail.

1 is a plan view showing the structure of an active matrix substrate according to the prior art, Figure 2 is a cross-sectional view showing the structure of the A-A portion in FIG.

As shown in FIG. 1, in the active matrix substrate according to the related art, a plurality of gate lines 3 are formed on a transparent insulating substrate 1, and a plurality of data lines 5 intersecting with the plurality of gate lines 3 are formed. The pixel electrode 7 is formed in each of the regions defined by the crossing of the plurality of gate lines 3 and the data lines 5, and the edges of the pixel electrodes 7 partially overlap the data lines 5. have. In the portion where the data line 5 and the pixel electrode 7 overlap, the light blocking film 11 is formed in parallel with the data line 5. A plurality of thin film transistors (TFTs) are formed at a portion where the gate line 3 and the data line 5 intersect, and each thin film transistor TFT has a center of the gate electrode 31 which is a part of the gate line 3. Two contact holes 9a and 9b are formed. The data line 5 and the semiconductor layer (not shown) of the thin film transistor TFT are connected through one 9a of the two contact holes 9a and 9b, and the thin film transistor is connected through the other 9b. The drain electrode (not shown) of the TFT and the pixel electrode 7 are connected.

FIG. 2 is a cross-sectional view showing a portion A of FIG. 1, in which a gate insulating film 2 is formed on a transparent substrate 1, and two data lines 5 are formed separately thereon. An interlayer insulating film 4 covering the data line 5 is formed on the substrate 1, is formed on the interlayer insulating film 4, and the light blocking film in which portions corresponding to the respective data lines 5 are separated. Part 11 overlaps with the data line 5, respectively. A pixel electrode 7 covering a portion of the light blocking film 11 and the interlayer insulating film 4 is formed separately from the portion corresponding to the data line 5.

The conventional method of manufacturing an active matrix substrate is the same as the method of manufacturing a substrate for a general liquid crystal display device up to the step of forming the data line 5 on the substrate 1.

An interlayer insulating film 4 covering the data line 5 is formed, and a metal film is deposited and patterned on the substrate 1 using a sputtering method to form a light blocking film 11, and then a pixel electrode 7 is formed.

However, such a conventional active matrix substrate and a method of manufacturing the same have a problem in that a photolithography process of depositing and patterning a metal film is additionally required to deposit a light blocking film. In addition, since the light blocking film is formed only at both edges of the pixel electrode, which is a part parallel to the data line in one unit pixel, a black matrix for blocking light in a part parallel to the gate line is widely formed on another substrate to open the aperture ratio. This has the problem of falling.

The present invention is to solve this problem, to minimize the process of forming the light blocking film and to minimize the formation of the black matrix to maximize the aperture ratio.

1 is a plan view showing the structure of an active matrix substrate according to the prior art.

2 is a cross-sectional view showing the structure of part A-A in FIG.

3 is a plan view showing the structure of an active matrix substrate according to an embodiment of the present invention.

4 to 8 are plan views showing a method of manufacturing an active matrix substrate according to an embodiment of the present invention in the order of their processes.

9 and 10 are cross-sectional views showing a method of manufacturing an active matrix substrate according to an embodiment of the present invention in the order of their processes.

In the active matrix substrate according to the present invention, a plurality of gate lines and data lines are formed to cross each other to define a pixel region, and pixel electrodes partially overlapping the gate lines and data lines are formed in the pixel region around the edges. A light blocking film is formed around the edge of the upper portion of the pixel electrode, and is connected to the gate line, and a branch of the gate line is formed at the edge of the pixel region in parallel with the data line.

The method of manufacturing an active matrix substrate according to the present invention crosses each other to form gate lines and data lines defining pixel regions. Next, the pixel electrode is formed by forming a thin film transistor including a gate electrode, a data electrode, and a source electrode formed in the same manner as the gate line and the data line, depositing a transparent conductive film and a metal film in sequence, and patterning the edge portion to overlap the gate line and the data line. Form. Subsequently, a light shielding film is formed by patterning a metal film using a protective film as a mask on portions other than the pixel area on the substrate so that only the edge of the pixel electrode is left.

In the method of manufacturing an active matrix substrate according to the present invention, the conductive film for the pixel electrode and the light blocking metal film are sequentially formed, and then the light blocking film is formed using the protective film formed thereafter as a mask. In addition, since the light blocking film is formed around the pixel electrode, light transmitted to the portion where the wiring is formed is reduced.

Next, an embodiment of an active matrix substrate and a method of manufacturing the same according to the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention.

3 is a plan view showing the structure of an active matrix substrate according to an embodiment of the present invention.

As shown in FIG. 3, in the active matrix substrate according to the present invention, a plurality of gate lines 300 are formed in a horizontal direction on a transparent insulating substrate 100, and a branch of the gate lines 300 defining a pixel region ( 310 is formed of two parts, each of which is connected to each other in the longitudinal direction. A plurality of data lines 500 in the vertical direction and a source electrode 510 made of the same material are formed to be separated from the data lines 500 while defining a lower portion of the pixel area in the horizontal direction.

Here, both edges of the data line 500 partially overlap the branch 310 of the gate line 300, and the source electrode 510 and the drain electrode are disposed at the intersection of the gate line 300 and the data line 500. A thin film transistor (TFT) having a terminal 520 and the gate electrode 320 as a terminal is formed.

In the pixel area defined by the gate line 300, the branch 310 of the gate line 300, and the source electrode 510, a portion of an edge thereof overlaps to form a transparent pixel electrode 700, and the pixel electrode 700 is formed. Around the edge of the light blocking film 110 made of an opaque material is formed.

The manufacturing method of the active matrix substrate according to the present invention is as follows.

4 to 8 are plan views illustrating a method of manufacturing an active matrix substrate according to an embodiment of the present invention, according to a process sequence, and FIGS. 9 and 10 illustrate a method of manufacturing an active matrix substrate according to an embodiment of the present invention. Sections B and C in Fig. 4 to Fig. 8 are shown in sequence, respectively, in accordance with the process sequence.

As shown in FIG. 4, in the method of manufacturing an active matrix substrate according to an exemplary embodiment of the present invention, a gate layer 300 is formed in a horizontal direction by forming and patterning a metal film on the substrate 100, and connected to the pixel. A branch 310 and a gate electrode 320 of the vertical gate line 300 defining the region are formed (see FIGS. 9A and 10A). The branch 310 is formed to be parallel to each other and connected to each other, and is used for light blocking to block light transmitted between the pixel electrode and the data line.

Subsequently, as shown in FIG. 5, a nitride film, an amorphous silicon layer, and an amorphous silicon layer doped with a high concentration of N-type impurities are sequentially deposited on the substrate 100, and an amorphous silicon layer is doped with an amorphous silicon layer and a high concentration of N-type impurities. The gate insulating film 200, the contact layer 410, and the active layer 400 are formed by patterning (see FIGS. 9B and 10B).

Next, as shown in FIG. 6, a metal film is deposited and patterned on the substrate 100 to form a data line 500 and a drain electrode 510 crossing the gate line 300. In addition, a thin film transistor TFT is formed by forming a source electrode 520 in parallel with the gate line 300 in a portion adjacent to the gate line 300 (see FIGS. 9C and 10C). The data line 500 is formed to partially overlap the branch 310 of the gate line 300 to have a light blocking function as described above, and the source electrode 510 is also parallel to the gate line 300. It is formed to have a light blocking function. In addition, the portion of the pixel area where the gate line 300 and the branch 310 are not formed may be formed to adjust the width of the data line 500 to form a pixel area circumference, thereby enhancing the effect of the light blocking function.

As shown in FIG. 7, the transparent conductive film and the metal film used for the electrode are sequentially deposited on the substrate 100 and patterned with a pixel mask to form the pixel electrode 700. In this case, the metal film 110a uses a metal having an etching selectivity with a metal on which the data line 500 is formed. The metal film 110a remains on the pixel electrode 700 and partially overlaps the branch 310 of the gate line, a portion of the gate line 300, and a source electrode 510 formed around the pixel area. (See FIGS. 9D and 10D). As described above, this part has a light blocking function and a function of forming a storage capacitor when a signal is applied.

Finally, as shown in FIG. 8, an oxide film or a nitride film is deposited on the substrate 100, and then patterned to expose the center portion of the pixel electrode 700 so as to expose the thin film transistor TFT, the gate line 300, and the gate line ( A passivation layer 600 is formed to protect the branch 310, the data line 500, and the pixel electrode 510 of 300. Subsequently, a part of the metal film 110a on the electrode 700 is etched using the protective 600 film as a mask to form the light blocking film 110.

In the active matrix substrate and the method of manufacturing the same according to the present invention, a metal film is sequentially deposited on the pixel electrode and then the metal film is left as a light blocking film by leaving the metal film only around the pixel electrode using the protective film as a mask. The dose can be adjusted.

Therefore, in the active matrix substrate and the manufacturing method thereof according to the present invention, the manufacturing process can be simplified by forming a light blocking film using a protective film as a mask without a separate photo etching process, and a light blocking film is formed around the pixel to form a light blocking effect. In addition, by forming the light blocking film as described above, the black matrix formed on the other substrate is formed to have a narrower width than in the prior art, thereby increasing the aperture ratio.

Claims (8)

A data line arranged on a transparent insulating substrate, a gate line intersecting the data line, a light blocking branch connected to the gate line and partially overlapping with the data line and formed in parallel with the data line, the gate line and the An active matrix substrate formed in a pixel region defined by a data line, the pixel electrode including a portion of the gate line and a data line overlapping an edge portion, and a light blocking layer formed around the pixel electrode. The active matrix substrate of claim 1, further comprising a source electrode formed in parallel with the gate line and connected to an edge portion of the pixel electrode. The active matrix substrate of claim 2, wherein the source electrode overlaps a portion of the light blocking layer. The active matrix substrate of claim 3, wherein the light blocking branches are formed in two portions at both edges of the data line, and portions thereof are connected to each other. The active matrix substrate of claim 4, further comprising a passivation layer formed on the light blocking layer. Forming a plurality of gate lines on a transparent insulating substrate, forming a gate insulating film and an active region on a portion of the gate lines, forming a data line intersecting the gate lines to form a pixel region, and transparent conducting on the substrate Forming a pixel electrode by depositing a film and an opaque layer and etching portions other than the pixel region by bordering portions where the gate line and the data line partially overlap, depositing an insulating film on the substrate and forming the pixel electrode on the pixel electrode. Forming a protective film by etching the insulating film so as to be exposed leaving only an edge of the opaque film, and forming a light blocking film by etching the opaque film using the protective film as a mask. The method of claim 6, further comprising forming a light blocking branch on a portion of the gate line and connected to the gate line and overlapping the data line and the pixel electrode. The method of claim 7, further comprising forming a source electrode parallel to the gate line and overlapping a portion of the pixel electrode while forming the data line.