KR100837884B1 - method for fabricating Liquid Crystal Display device - Google Patents

Abstract

The present invention relates to a method of manufacturing a liquid crystal display device which can reduce the number of photomasks.

A method of manufacturing a liquid crystal display device according to the present invention includes sequentially forming a first photoresist film pattern on which a first metal film and a gate electrode forming region are defined on a glass substrate, and using the first photoresist film pattern as a mask. Forming a gate electrode by removing the first photoresist pattern; and defining a gate insulating film, an amorphous silicon layer, a transparent conductive film, a second metal film, a semiconductor layer, and a pixel electrode forming region on a substrate including the gate electrode. Forming a second photoresist pattern, forming a semiconductor layer and a pixel electrode by removing the second metal film, the transparent conductive film, and the amorphous silicon layer using the second photoresist pattern as a mask, and the second photoresist pattern Removing the pixels to form a third photoresist pattern, and etching the remaining second metal layer by using the third photoresist pattern as a mask. Forming each source / drain electrode, removing the third photoresist pattern, sequentially forming a fourth photoresist pattern having an active layer, a protective film, and a pixel region defined on the substrate including the source / drain; And removing the active layer and the protective film using the fourth photoresist pattern as a mask, and removing the fourth photoresist pattern.

Description

Method for fabricating Liquid Crystal Display device

1 is a plan view of a liquid crystal display according to the prior art.

2A to 2E are cross-sectional views taken along the line II of FIG. 1.

3 is a plan view of a liquid crystal display according to the present invention;

4A to 4D are cross-sectional views taken along line III-IV of FIG. 3.

Explanation of symbols for main parts of the drawings

200. Glass substrate 202. Gate

204. Gate insulating film 205. Semiconductor layer

211. Pixel electrodes 222, 224, 226. Photoresist pattern

207, 208. Source / drain

The present invention relates to a method of manufacturing a liquid crystal display device, and more particularly, to a method of manufacturing a liquid crystal display device which can reduce the number of photomasks.

As is generally known, liquid crystal displays (hereinafter referred to as LCDs) have characteristics such as light weight, thinness, and low power consumption, so that instead of cathode ray tubes (CRTs), various types of information devices can be used. It is used in terminals or video equipment. In particular, a TFT-LCD equipped with a thin film transistor (hereinafter referred to as TFT) has an advantage in that it is possible to realize a high quality and a large display device because it has excellent response characteristics and is suitable for high pixel numbers.

1 is a plan view of a liquid crystal display according to the prior art.

The TFT-LCD (Thin Film Transistor-Liquid Crystal Display) structure according to the prior art, as shown in Figure 1, the gate line (gate line) 110 and the data line on the glass substrate (glass substrate) (100) The data lines 120 are arranged to cross in a direction perpendicular to each other, and a thin film transistor is formed at a portion where the gate line 110 and the data line 120 cross each other.

The thin film transistor includes a gate electrode 102 having a shape protruding on one side of the gate line 110, and source / drain electrodes 107 and 108 on both sides of the gate electrode 102.

The pixel electrode 114 is arranged to have a stacked capacitor (not shown) in the pixel region (not shown) between the gate line 110 and the data line 120. Here, a gate insulating film (not shown) for insulating the data line 120 is arranged on the gate line 110 and the gate electrode 102.

2A to 2E are cross-sectional views taken along the line II of FIG. 1.

In the method of manufacturing a liquid crystal display device according to the related art having the above structure, as illustrated in FIG. 2A, after depositing a first metal film on the glass substrate 100, a photosensitive film is coated on the first metal film. Exposure and development are performed to form the first photoresist pattern 120 having the gate electrode formation region defined therein. Subsequently, the gate electrode 102 is formed by removing the metal layer using the first photoresist layer pattern 120 as a mask.

Next, as shown in FIG. 2B, after removing the first photoresist layer pattern, an amorphous silicon layer not doped with impurities and an amorphous silicon layer doped with impurities are sequentially formed on a substrate including the gate electrode 102. The second photoresist layer pattern 122 is formed on the amorphous silicon layer doped with the impurity.

Next, the semiconductor layer 106 is formed by etching the second photoresist pattern 122 as a mask and etching the amorphous silicon layer without the impurities and the amorphous silicon layer doped with the impurities. In this case, the amorphous silicon layer doped with the remaining impurities becomes an ohmic contact layer. In addition, a gate insulating film 104 is interposed between the gate electrode 102 and the semiconductor layer 106.

Next, as shown in FIG. 2C, the second photoresist pattern is removed. Thereafter, after depositing a second metal film on the substrate including the semiconductor layer 106, a third photoresist pattern 124 having a source / drain formation region is defined on the second metal film. Subsequently, the source / drain electrodes 107 and 108 are formed by using the third photoresist pattern 124 as a mask and removing the second metal layer.

Next, as shown in FIG. 2D, the third photoresist pattern is removed.                         

Thereafter, a protective film 110 is deposited on the substrate including the source / drain electrodes 107 and 108 using a silicon oxide film or the like, and then a portion corresponding to the drain electrode 108 on the protective film 110. A fourth photosensitive film pattern 126 is formed to expose the film.

Next, the fourth photoresist layer pattern 126 is used as a mask to etch the protective layer 110 to form a contact hole 112.

Next, as shown in FIG. 2E, the fourth photoresist pattern is removed. Thereafter, a transparent conductive film such as indium tin oxide (ITO) is formed on the passivation layer 110 to cover the contact hole 112, and then a fifth photoresist layer pattern 128 having pixel regions defined thereon is formed on the transparent conductive layer. To form. Subsequently, the pixel electrode 114 is formed by etching the transparent conductive film using the fifth photoresist pattern as a mask. Then, the fifth photosensitive film pattern is removed.

However, in the manufacturing method of the liquid crystal display device according to the prior art, the photo process for forming the mask is performed five times, which leads to a problem in that the productivity is reduced, such as complicated manufacturing process and increased process time and process cost.

Accordingly, an object of the present invention is to provide a method for manufacturing a liquid crystal display device which can improve productivity by reducing the number of photo processes.

According to an aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device, the method including sequentially forming a first photoresist layer pattern having a first metal layer and a gate electrode formation region on a glass substrate, and masking the first photoresist layer pattern. Removing the first metal film to form a gate electrode, removing the first photosensitive film pattern, and forming a gate insulating film, an amorphous silicon layer, a transparent conductive film second metal film and a semiconductor layer on a substrate including the gate electrode; Forming a second photoresist film pattern in which a pixel electrode formation region is defined, and removing the second metal film, the transparent conductive film, and the amorphous silicon layer using the second photoresist film pattern as a mask to form respective semiconductor layers and pixel electrodes; And performing a second photoresist pattern ashing to remove the pixel side to form a third photoresist pattern, and using the third photoresist pattern as a mask and remaining Etching each of the second metal layers to form respective source / drain electrodes; removing the third photoresist pattern; and forming a fourth photoresist pattern having an active layer, a protective layer, and a pixel region on a substrate including the source / drain. And sequentially forming the mask, removing the active layer and the protective film using the fourth photoresist pattern as a mask, and removing the fourth photoresist pattern.

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

3 is a plan view of a liquid crystal display according to the present invention.

In the liquid crystal display according to the present invention, as shown in FIG. 3, the gate line 210 and the data line 220 are arranged on the glass substrate 200 so as to cross in a direction perpendicular to each other. The thin film transistor is formed at the intersection of the 210 and the data line 220.                     

The thin film transistor includes a gate electrode 202 having a shape protruding on one side of the gate line 210, and source / drain electrodes 207 and 208 on both sides of the gate electrode 202.

A pixel electrode formed in a pixel region (not shown) between the gate line 210 and the data line 220 and covering the source / drain electrodes 207 and 208, and partially overlapping the gate electrode 202. 211 is arranged. In addition, a gate insulating film (not shown) for insulating the data line 220 is arranged on the gate line 210 and the gate electrode 202.

4A to 4D are cross-sectional views taken along line III-IV of FIG. 3.

In the method of manufacturing a liquid crystal display according to the present invention, as shown in FIG. 4A, after depositing a first metal film on the glass substrate 200, a gate electrode forming region is defined on the first metal film. 1 Photosensitive film pattern 222 is formed. Subsequently, the first metal film is etched using the first photoresist pattern 222 as a mask to form a gate electrode 202.

Then, as shown in FIG. 4B, the first photoresist pattern is removed. Thereafter, silicon oxide is chemically vapor deposited on the substrate including the gate electrode 202 to form a gate insulating film 204.

Subsequently, an amorphous silicon layer (a-Si) doped with impurities and an amorphous silicon layer (n + a-Si) doped with impurities, a transparent conductive film, and a second metal film are sequentially formed on the gate insulating layer 204. A second photoresist layer pattern 224 having an active layer and a pixel electrode formation region is formed on the second metal layer.

Thereafter, the second photoresist layer pattern 224 is used as a mask, and the second metal layer, the transparent conductive layer, an amorphous silicon layer (n + a-Si) doped with impurities, and an amorphous silicon layer (a-Si not doped with impurities) are used. In this case, the remaining transparent conductive film becomes the pixel electrode 211, and the silicon layer (n + a-Si) and the amorphous silicon layer (a-Si) doped with the remaining impurities are respectively an ohmic contact layer. (Not shown) and the semiconductor layer 205. Reference numeral 212 denotes a remaining second metal film.

Subsequently, the second photoresist pattern ashing is performed to remove the pixels, thereby forming the third photoresist pattern 225 as illustrated in FIG. 4C. Subsequently, the third photoresist pattern 225 is used as a mask, and the remaining second metal layer is etched again to form respective sources / drains 207 and 208. Next, as shown in FIG. 4D, the third photoresist pattern is removed.

Next, an active layer 213 and a passivation layer (not shown) are deposited on the substrate including the source / drain 207 and 208, and then a fourth photoresist layer pattern 226 having pixel regions defined on the passivation layer is formed. To form. Thereafter, the fourth photoresist pattern 226 is used as a mask, and the protective layer and the activation layer are removed to open the pixel region.

As described above, in the method of the present invention, as the photo process is performed three times, the manufacturing process is simplified, and the process time, process time, and process cost are reduced. Therefore, the productivity of the product is improved.                     

In addition, this invention can be implemented in various changes within the range which does not deviate from the summary.

Claims (2)

Sequentially forming a first photoresist film pattern having a first metal film and a gate electrode forming region on the glass substrate; Forming a gate electrode by using the first photoresist pattern as a mask and removing the first metal layer; Removing the first photoresist pattern; Forming a second photoresist layer pattern on which a gate insulating layer, an amorphous silicon layer, a transparent conductive film second metal film and a semiconductor layer, and a pixel electrode forming region are defined on a substrate including the gate electrode; Removing the second metal film, the transparent conductive film, and the amorphous silicon layer using the second photoresist pattern as a mask to form respective semiconductor layers and pixel electrodes; Performing a second photoresist pattern ashing to remove the pixel side to form a third photoresist pattern; Using the third photoresist pattern as a mask and etching the remaining second metal layer to form respective source / drain electrodes; Removing the third photoresist pattern; Sequentially forming a fourth photoresist pattern on which the active layer, the passivation layer, and the pixel region are defined on the substrate including the source / drain; Removing the active layer and the protective layer using the fourth photoresist pattern as a mask; And removing the fourth photoresist pattern. The method of claim 1, wherein the semiconductor layer, the pixel electrode, and the source / drain electrode are formed in the same chemical vapor deposition chamber.

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