KR20030025516A - A thin film transistor panels for liquid crystal display for reflection type and methods for manufacturing the same - Google Patents

Abstract

PURPOSE: A thin film transistor substrate for a reflective liquid crystal display device and a method for fabricating the same are provided to simplify the fabricating procedure by forming an embossing pattern on a photosensitive film for black matrix by using a black positive photosensitive film. CONSTITUTION: A method for fabricating a thin film transistor substrate for a reflective liquid crystal display device includes the steps of forming gate and data wires on an insulating substrate via a gate insulating film covering the gate wires or a semiconductor pattern formed on the gate insulating film on gate electrodes, forming a black matrix insulating film on the data wires and the semiconductor pattern by using a black photosensitive film, and forming a reflecting film connected to drain electrodes by using a conductive material with flexibility on the black matrix insulating film. The insulating film for the black matrix(80) is formed by the sub-steps of doping the photosensitive film, embossing the photosensitive film at positions corresponding to pixel areas by exposing and developing the photosensitive film by using mask, and forming first to third contact holes(101-103) for exposing the drain electrodes(62) and gate and data pads(24,64). The insulating film for the black matrix is flat at positions corresponding to the gate and data pads.

Description

A thin film transistor substrate for a reflective liquid crystal display device and a method for manufacturing the same {A THIN FILM TRANSISTOR PANELS FOR LIQUID CRYSTAL DISPLAY FOR REFLECTION TYPE AND METHODS FOR MANUFACTURING THE SAME}

The present invention relates to a thin film transistor substrate for a liquid crystal display device and a method for manufacturing the same, and more particularly, to a thin film transistor substrate for a reflective liquid crystal display device and a method for manufacturing the same.

A liquid crystal display device is composed of a pair of transparent glass substrates on which electrodes are formed, a liquid crystal layer between two glass substrates, and two polarizing plates attached to an outer surface of each glass substrate to polarize light. It can be divided into a transmissive type for displaying an image using a back light and a reflective type for displaying an image using natural light.

In general, a reflective liquid crystal display includes a lower substrate in which a thin film transistor and a reflective film are formed in each pixel, a black matrix covering the pixel, and an upper substrate in which a color filter is formed in the pixel.

The reflective liquid crystal display device reduces the aperture ratio and reflectance of the pixel because the black matrix is formed to be wider so that they overlap each other in consideration of the misalignment of the reflective film and the black matrix. In order to minimize the decrease of the aperture ratio of the pixel due to misalignment of the upper and lower substrates. In this case, the black matrix is formed using a negative photosensitive material.

On the other hand, in order to maximize the reflectance of the reflective liquid crystal display device, the reflective film is preferably formed on the organic insulating film having an embossing pattern.

In the method of manufacturing such a reflective liquid crystal display device, since the black matrix uses a negative photosensitive film material and the organic insulating film uses a positive photosensitive material, a separate mask is required to process them. This causes a problem in that the manufacturing process is complicated.

An object of the present invention is to simplify the manufacturing process of the reflective liquid crystal display device.

1 is a layout view of a thin film transistor substrate for 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,

3A is a layout view illustrating a manufacturing process of a thin film transistor substrate for a liquid crystal display according to an exemplary embodiment of the present invention.

3B is a cross-sectional view taken along line IIIb-IIIb 'of FIG. 3A.

FIG. 4A is a layout view of a thin film transistor substrate manufactured according to an embodiment of the present invention, and illustrates the next step of FIG. 3A.

4B is a cross-sectional view taken along line IVb-IVb 'of FIG. 4A.

FIG. 5A is a layout view of a thin film transistor substrate manufactured according to an embodiment of the present invention, and illustrates the next step of FIG. 4A.

5B is a cross-sectional view taken along line Vb-Vb ′ of FIG. 5A.

FIG. 6A is a layout view of a thin film transistor substrate manufactured according to an embodiment of the present invention, and illustrates the next step of FIG. 5A.

FIG. 6B is a cross-sectional view taken along line VIb-VIb ′ of FIG. 5A;

FIG. 7A is a layout view of a thin film transistor substrate manufactured according to an embodiment of the present invention, and illustrates the next step of FIG. 6A.

FIG. 7B is a cross-sectional view taken along the line VIIb-VIIb 'of FIG. 7A;

FIG. 7C is a cross-sectional view illustrating the next step in FIG. 7B.

In order to solve this problem, in the present invention, a thin film transistor substrate for a reflective liquid crystal display device and a method of manufacturing the same are formed using a black positive photosensitive film material to form an insulating film for a black matrix having an embossing pattern on the surface thereof, and forming a reflective film thereon. Form.

According to an embodiment of the present invention, a gate wiring including a gate line, a gate electrode, and a gate pad is formed on an insulating substrate. Next, a gate insulating film covering the gate wiring is formed. Next, a semiconductor pattern is formed over the gate insulating film of the gate electrode. Next, a data line including a data line, a source electrode, a drain electrode, and a data pad is formed on the semiconductor pattern or the gate insulating layer. Next, an insulating film for a black matrix is formed on the data line and the semiconductor pattern by using a black photosensitive film. Next, a reflective film connected to the drain electrode is formed on the black matrix insulating layer by using a conductive material having a reflectance.

In this case, the photoresist film may include a black pigment of a carbon-based pigment or a black pigment in which dyes of R (red), G (green) and B (blue) are mixed, and an acrylic-based binder.

In this case, the forming of the insulating film for the black matrix may be performed by applying a photoresist film, exposing and developing the photoresist film using a mask to emboss the first process and to expose the drain electrode, the gate pad, and the data pad, respectively. And forming a third contact hole.

In this case, the method may further include forming a protective film covering the semiconductor pattern and the data line before the forming of the black matrix insulating film.

A thin film transistor substrate for a reflective liquid crystal display device includes a gate wiring including a gate line and a gate electrode, a gate insulating film covering the gate wiring, a semiconductor pattern formed over the gate insulating film of the gate electrode, and a semiconductor pattern or the upper gate insulating film. A data wiring including a data line, a source electrode, and a drain electrode, formed on the data wiring and the semiconductor, and formed on the black matrix insulating film made of a black photosensitive material, and on the black matrix insulating film. And a reflective film connected to the drain electrode.

In this case, the photosensitive material may include a carbon-based black pigment or a combination of a black pigment and an acrylic-based dye in which R (red), G (green), and B (blue) pigments are mixed.

At this time, the surface of the insulating film for black matrix corresponding to the pixel region is preferably treated by embossing.

In this case, the method may further include a protective film formed under the black matrix insulating film.

In this case, the gate wiring further includes a gate pad connected to the gate line, the data wiring further includes a data pad connected to the data line, and the insulating layer for the black mattress exposes the drain electrode, the gate pad, and the data pad, respectively. It may further comprise first, second and third contact holes.

Then, a thin film transistor substrate for a reflective liquid crystal display device and a method for manufacturing the same according to an exemplary embodiment of the present invention will be described with reference to the accompanying drawings so that those skilled in the art can easily perform the same. It explains in detail.

First, a structure of a thin film transistor substrate for a reflective liquid crystal display device 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 thin film transistor substrate for a reflective liquid crystal display device 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.

1 and 2, gate wirings 20, 22, 24, and 26 extending in the horizontal direction are formed on the insulating substrate 10. The gate lines 20, 22, 24, and 26 are connected to the gate line 20, the gate electrode 22 connected to the gate line 20, and the ends of the gate line 20 to receive a scan signal from the outside. A gate pad 24 to be transferred to the gate line 20, and a storage electrode line 26 parallel to the gate line 20 and forming one electrode of the storage capacitor. Here, the storage electrode line 26 overlaps with the reflective film to be described later to form a storage capacitor that improves the charge storage capability.

A gate insulating film 30 made of silicon nitride or the like is formed on the gate wirings 20, 22, 24, and 26. A semiconductor pattern 40 made of amorphous silicon or the like is formed on the gate insulating film 30 on the gate electrode 22. On the semiconductor pattern 40, resistive contact layers 51 and 52, which are divided into two with respect to the gate electrode 22 and made of doped amorphous silicon, are formed.

Data wirings 60, 61, 62, 64, and 66 are formed on the ohmic contact layers 51, 52. FIG. The data wires 60, 61, 62, 64, and 66 are formed in a vertical direction and intersect the gate line 20 to define a pixel area and a source electrode connected to the data line 60. 61, a drain electrode 62 facing the source electrode 61 with respect to the gate electrode 22, and a data pad 64 connected to an end of the data line 60 to receive an image signal from the outside. do. In addition, the data lines 60, 61, 62, 64, and 66 include a conductor pattern 66 for a storage capacitor connected to the drain electrode 62 and the connection portion 63 and overlapping the storage electrode line 26. do.

On the data lines 60, 61, 62, 64, 66, the semiconductor pattern 40, and the gate insulating film 30, a protective film 70 made of an organic insulating material such as silicon nitride or acrylic is formed. In this case, the protective layer 70 may not be formed in some cases.

The black matrix insulating film 80 having excellent planarization characteristics is formed on the passivation film 70. The black matrix insulating layer 80 is formed of a positive type photosensitive material. The positive type photosensitive material is a black pigment of carbon series or a black pigment mixed with pigments of R (red), G (green), and B (blue) and acrylic (acrylate). ) Is a family of binder (binder). Meanwhile, the black matrix insulating layer 80 may be formed of a negative photosensitive material. The black matrix insulating film 80 has a protective film 70 and contact holes 101, 102, 103 that expose the gate pad 24, the drain electrode 62, and the data pad 64, respectively. At this time, the black matrix insulating film 80 corresponding to the pixel region is processed by embossing, and the black matrix insulating film 80 around the pads 24 and 64 has a flat structure.

On the black matrix insulating film 80 corresponding to the pixel region, a reflective film 90 connected to the drain electrode 62 is formed through the contact hole 102. The reflecting film 90 is made of aluminum or aluminum-neodymium alloy having high reflectivity.

In the structure of the reflective liquid crystal display device, a black matrix insulating film 80 formed of a positive photosensitive material and having an embossed region corresponding to the pixel region and a reflective film 90 thereon are formed on the thin film transistor substrate to form an image. It is possible to maximize the reflectance by greatly reducing the decrease in the aperture ratio resulting from misalignment due to the bottom plate alignment.

Next, a method of manufacturing a thin film transistor substrate for a reflective liquid crystal display device according to an exemplary embodiment of the present invention will be described in detail with reference to FIGS. 3A to 7C.

First, as shown in FIGS. 3A and 3B, a metal or conductor layer such as aluminum or an aluminum alloy, molybdenum or molybdenum-tungsten alloy, chromium, tantalum, or the like is deposited on the insulating substrate 10, and a photolithography using a mask is performed. The process is performed to form gate wirings 20, 22, 24, and 26 including the gate lines 20, the gate electrodes 22, the gate pads 24, and the storage electrode lines 26.

Next, as shown in FIGS. 4A and 4B, the gate insulating layer 30 made of silicon nitride, silicon oxide, or the like is formed on the substrate 10 on which the gate wirings 20, 22, 24, and 26 are formed. The semiconductor layer 40 and the three-layer film of the doped amorphous silicon layer 50 are successively stacked, and the semiconductor layer 40 and the doped amorphous silicon layer 50 are patterned by a patterning process using a mask to form the gate electrode 26 and The semiconductor pattern 40 and the ohmic contact layer 50 are formed on the gate insulating layer 30 facing each other.

Next, as illustrated in FIGS. 5A and 5B, a conductor layer such as molybdenum, molybdenum alloy, chromium, or the like is deposited on the ohmic contact layer 50, and a photolithography process is performed using a mask to generate the data line 60 and the source. Data wirings 60, 61, 62, 64, and 66 are formed including the electrode 61, the drain electrode 62, the data pad 64, and the conductive pattern 66 for the storage capacitor. At this time, the conductive capacitor pattern 66 for the storage capacitor is connected to the drain electrode 62 and the connection portion 63.

Subsequently, the doped amorphous silicon layer 50 not covered by the data wires 60, 61, 62, 64, and 66 is etched and separated on both sides of the gate electrode 22, and both doped amorphous silicon layers ( The semiconductor layer pattern 40 between 51 and 52 is exposed.

6A and 6B, a protective film 70 made of silicon nitride is stacked, and then a black black matrix insulating film 80 is coated on the protective film 70 with excellent planarization characteristics. . The black matrix insulating layer 80 is formed of a positive type material as a photosensitive material. The positive type material is a carbon-based black pigment having a property of absorbing light, or R (red) or G (rust). And a black pigment mixed with a pigment of B (blue) and an acrylate-based binder. In this case, the black matrix insulating layer 80 may be formed of a negative type material as a photosensitive material. Here, the protective film 70 may not be formed in some cases.

Next, as shown in FIGS. 7A and 7B, the black matrix insulating film 80 is exposed and developed by a photo process using a mask to form embossing patterns and contact holes 101, 102, 103. In this case, the mask is disposed on the black matrix insulating layer 80. That is, a mask is disposed in a portion corresponding to the gate pad 24, the drain electrode 62, and the data pad 64 so as to have a transmissive region through which light is transmitted, and convex upward of the portion corresponding to the pixel region. A mask is disposed so as to have a semi-transmissive area by forming a light shielding area that blocks incident light in the floor corresponding to the floor and a slit or lattice pattern in a part corresponding to the valley that is concave upward. On the other hand, when the black matrix insulating film 80 is negative photosensitive, the transmission region and the light shielding region are switched to each other. When the black matrix insulating film 80 is exposed using such a mask, the polymers are completely decomposed at the portion directly exposed to the light through the transmission region, and the polymers are completely decomposed at the portion where the slit pattern is formed. It is in the state which is not, and a polymer hardly decomposes in the part corresponding to a light shielding area. Next, when the black matrix insulating film 80 is developed, most of the polymer molecules are not decomposed, and only a part of the black matrix insulating film 80 is removed in the portion irradiated with little light to form an uneven structure on the surface of the insulating film. The black matrix insulating film 80 is removed in the portion directly exposed to the contact hole. Although the process of forming the embossing pattern and the contact hole by using a single mask has been described above, a mask for forming the embossed pattern and a mask for forming the contact hole may be used separately.

By using the black positive photosensitive film on the reflective thin film transistor substrate to form an embossing pattern on the black matrix insulating layer 80 together, the manufacturing process can be simplified, thereby reducing the manufacturing cost.

Next, as shown in FIG. 7C, the protective film 70 is etched to form contact holes 101, 102, and 103 that expose the gate pad 24, the drain electrode 26, and the data pad 64, respectively.

Next, as shown in Figs. 1 and 2, after depositing a reflective film 90 made of a conductor such as aluminum or aluminum-neodymium alloy having high reflectivity on the photosensitive film 85 for the embossed black matrix, the mask is applied. The reflective film 90 is formed in the pixel region by the photolithography process.

As described above, according to the present invention, by using the black positive photosensitive film on the thin film transistor substrate, the embossing pattern is formed on the insulating film for the black matrix together to simplify the manufacturing process, thereby reducing the manufacturing cost. In addition, by forming an insulating film for a black matrix on the thin film transistor substrate and a reflective film thereon, a decrease in the aperture ratio resulting from misalignment due to top and bottom plate alignment can be greatly reduced, thereby maximizing the reflectance.

Claims (9)

Forming a gate wiring including a gate line, a gate electrode, and a gate pad on the insulating substrate, Forming a gate insulating film covering the gate wiring; Forming a semiconductor pattern on the gate insulating layer of the gate electrode; Forming a data line including a data line, a source electrode, a drain electrode, and a data pad on the semiconductor pattern or the gate insulating layer; Forming an insulating film for a black matrix using a black photoresist film on the data line and the semiconductor pattern; Forming a reflective film connected to the drain electrode by using a conductive material having a reflectance on the insulating film for the black matrix; Method of manufacturing a thin film transistor substrate for a reflective liquid crystal display device comprising a. In claim 1, The photosensitive film is a method of manufacturing a thin film transistor substrate for a reflective liquid crystal display device comprising a black pigment of a carbon series or a black pigment in which R (red), G (green), and B (blue) pigments are mixed with an acryl-based combination. . In claim 1, Forming the black matrix insulating film, Applying the photosensitive film, Embossing treatment by exposing and developing the photoresist using a mask and Forming first, second and third contact holes exposing the drain electrode, the gate pad and the data pad, respectively; Method of manufacturing a thin film transistor substrate for a reflective liquid crystal display device comprising a. In claim 1, And forming a passivation layer covering the semiconductor pattern and the data line before the forming of the insulating film for the black matrix. Insulation board, A gate wiring formed on the substrate and including a gate line and a gate electrode; A gate insulating film covering the gate wiring, A semiconductor pattern formed on the gate insulating film of the gate electrode; A data line formed on the semiconductor pattern or the gate insulating layer and including a data line, a source electrode, and a drain electrode; An insulating film for a black matrix formed on the data line and the semiconductor and made of a black photosensitive material; A reflective film formed on the black matrix insulating film and connected to the drain electrode. Thin film transistor substrate for a reflective liquid crystal display comprising a. In claim 5, The photosensitive material is a thin film transistor substrate for a reflective liquid crystal display device comprising a combination of a black pigment of the carbon series or a pigment of R (red), G (green), B (blue) and an acrylic series. In claim 5, A thin film transistor substrate for a reflective liquid crystal display device wherein an insulating surface for the black matrix corresponding to the pixel region is treated by embossing. In claim 5, And a passivation layer formed under the black matrix insulating layer. In claim 5, The gate line further includes a gate pad connected to the gate line, and the data line further includes a data pad connected to the data line. The insulating film for black mattress further includes first, second and third contact holes exposing the drain electrode, the gate pad and the data pad, respectively.