KR19990084316A - Method of manufacturing liquid crystal display device having top gate thin film transistor structure - Google Patents

Abstract

A method of manufacturing a liquid crystal display device having a top gate thin film transistor structure forms a top gate thin film transistor, a color filter, and a black matrix together on a glass substrate. The black matrix is formed together in forming the shield layer of the thin film transistor, and the color filter is formed on the shield layer. The active layer and the gate electrode of the thin film transistor may be continuously formed in one process or may be respectively formed in separate processes. The interlayer insulating film is formed of an organic insulating film and is formed in a spin on glass manner. The common electrode is formed on a surface of the plastic substrate opposite the glass substrate. Therefore, the structure is simple, the manufacturing efficiency is improved, and the weight is light.

Description

Method of manufacturing liquid crystal display device having top gate thin film transistor structure

The present invention relates to a method of manufacturing a liquid crystal display (LCD) having a top gate thin film transistor (TFT) structure, and more specifically, to a glass substrate, A manufacturing method of a thin film transistor liquid crystal display device which together forms a color filter.

In general, a thin film transistor liquid crystal display includes a bottom gate thin film transistor structure capable of continuously depositing a gate insulating layer of a thin film transistor, SiNx, and an a-Si layer operating as an active channel. Has been mainly used.

On the other hand, in the top gate thin film transistor structure (staggered type), since the SiNx is deposited after the a-Si layer which is processed at a slightly lower temperature than SiNx, the hydrogenation of a-Si during high temperature SiNx deposition is performed. Although the ratio of the a-Si, which should have an appropriate amount of hydrogen content, is deteriorated due to the small ratio, this structure is easier to reduce the resistance of the gate wiring and lower the number of photo masks compared to the bottom gate thin film transistor structure. Some of these cursors are used.

Hereinafter, a liquid crystal display having a conventional top gate thin film transistor structure will be described with reference to the accompanying drawings.

1 is a diagram illustrating a structure of a liquid crystal panel having a conventional top gate thin film transistor structure.

As shown in FIG. 1, a liquid crystal panel having a conventional top gate thin film transistor structure includes a glass substrate 1 and a color filter substrate 17 connected through a liquid crystal on the glass substrate 1.

At this time, a chromium (Cr) shield layer 3 is formed on the glass substrate 1, and a SiNx insulating film 5 is entirely deposited on the shield layer 3.

Further, source / drain electrodes 7 and 7 'are formed on the SiNx insulating film 5, a-Si layer 9 is formed on the source / drain electrodes 7 and 7', and an a-Si layer. On (9), the SiNx insulating layer 11 is formed as a whole. The gate electrode 13 and the indium titanium oxide (ITO) pixel electrode 15 are formed on the SiNx insulating layer 11.

On the other hand, a color filter made of a resin film containing a dye or pigment of three basic colors (Red, Green, Blue, hereinafter R, G, B) on the surface facing the glass substrate 1 from the color filter substrate 17 19 is disposed so as to correspond to the pixels of the glass substrate 1, and a black matrix (BM: Black Matrix) 19 made of chromium (Cr) is formed between the pixels to block leakage light. An ITO common electrode 19 is formed on the color filter 19.

In this way, the thin film transistor and the color filter are patterned and assembled on the glass substrate 1 and the color filter substrate 17, respectively, so that the error of each substrate is 10 μm in the manufacturing process of the conventional thin film transistor liquid crystal display device. Smaller than 3 μm occurs at a level of 3 μm or less, which causes a significant decrease in the aperture ratio, furthermore, a decrease in the transmittance and eventually an increase in power consumption.

In addition, in the conventional method of manufacturing a liquid crystal display device having a top gate thin film transistor structure, since the vicinity of the a-Si layer is directly exposed to backlight light, the characteristics of the thin film transistor are affected by the photo leakage current. Due to this deterioration, a shielding layer for backlight light blocking must be separately formed, and in the color filter substrate, the influence of the parasitic capacitance between the data line and the ITO pixel electrode and the generation of the rubbing inclined line that can occur during rubbing can be obtained. Since a black matrix is formed in order to prevent light leakage, there is a problem in that a light blocking film must be formed in duplicate.

Accordingly, an object of the present invention is to solve the above-described problems, and by forming a top gate thin film transistor and a color filter together on a glass substrate, there is provided a method of manufacturing a liquid crystal display device having a simple structure and improved manufacturing efficiency. There is.

1 is a view showing the structure of a liquid crystal panel having a conventional top gate thin film transistor structure,

2 is a structural diagram of a liquid crystal display panel having a top gate thin film transistor structure according to the first embodiment of the present invention;

3 is a structural diagram of a liquid crystal display panel having a top gate thin film transistor structure according to a second embodiment of the present invention.

In order to achieve the above object, the present invention forms a thin film transistor having a top gate structure, a color filter, and a black matrix together on a glass substrate.

That is, while forming a top gate structured thin film transistor on a glass substrate, a color filter and a black matrix are also formed through the same process.

In more detail, a shield layer and a black matrix are formed together on a glass substrate, and then a color filter is formed thereon. Next, a source / drain electrode is formed over the color filter, and an active layer is formed over the source / drain electrode. Next, a gate electrode is formed over the active layer, an interlayer insulating film is formed, and finally a pixel electrode is formed.

In this case, the active layer and the gate electrode may be formed through one process.

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

2 is a structural diagram of a liquid crystal display panel having a top gate thin film transistor structure according to the first embodiment of the present invention.

As shown in FIG. 2, the liquid crystal panel according to the first embodiment of the present invention includes a glass substrate 20 and a plastic substrate 30.

On the glass substrate 20, a layer 40 having a shield layer and a black matrix formed together is formed, and the shield layer and the black matrix are formed together through the same process.

A color filter (not shown) is formed on the layer 40, and then an organic insulating film 50 is coated on the color filter, and a SiNx insulating film 60 is deposited on it.

Next, source / drain electrodes 70 and 70 'are formed on the SiNx insulating film 60, and a-Si active layer 80 is formed on the source / drain electrodes 70 and 70'.

On the a-Si active layer 80, a SiNx insulating layer 90 is deposited on the entire surface, and a gate electrode 100 is formed thereon.

Next, the interlayer insulating protective film 110 is formed entirely, and the ITO pixel electrode 120 is formed thereon.

In this case, the interlayer insulating protection film 110 is formed of a spin on glass method using an organic insulating film. As the organic insulating layer, organic materials such as acrylic resin, polyimide, Benzo cyclobutene (BCB), and per fluorocyclobutene (PFCB) may be applied.

On the other hand, the surface facing the glass substrate 20 of the plastic substrate 30 does not have a black matrix or a color filter, and only the common electrode 130 is formed.

3 is a structural diagram of a liquid crystal display panel having a top gate thin film transistor structure according to a second embodiment of the present invention.

As shown in FIG. 3, the liquid crystal panel according to the second embodiment of the present invention forms source / drain electrodes 70 and 70 ′ on the glass substrate 20 during the manufacturing process as described in the first embodiment. Since it is the same until it does so, it abbreviate | omits here and demonstrates from the next process.

In the first embodiment, the a-Si active layer 80, the SiNx insulating layer 90, and the gate electrode 100 are formed on the source / drain electrodes 70 and 70 'by a separate process. The a-Si active layer 140, the SiNx insulating layer 150, and the gate electrode 160 are formed on the drain electrodes 70 and 70 ′ through a continuous process and then etched.

Next, the interlayer insulating protective film 170 made of acrylic resin is formed on the entire surface, and the ITO pixel electrode 180 is formed thereon.

On the other hand, the plastic substrate 30, as in the first embodiment, only the common electrode 130 is formed on the surface facing the glass substrate 20.

As described above, in the embodiment of the present invention, by forming the top gate thin film transistor and the color filter together on the glass substrate, the structure is simple, the manufacturing efficiency is improved, and the top plate is formed on the plastic substrate because the color filter is formed together on the bottom glass substrate. Since it can be formed using the present invention can provide a method for manufacturing a liquid crystal display device that can significantly reduce the weight.

Although this invention has been described with reference to the most practical and preferred embodiments, the invention is not limited to the embodiments disclosed above, but also includes various modifications and equivalents within the scope of the following claims.

Claims (4)

Forming a shield layer and a black matrix together on the glass substrate; Forming a color filter on the shield layer; Forming a source / drain electrode over the color filter; Forming an active layer over the source / drain electrodes; Forming a gate electrode on the active layer; Forming an interlayer insulating film on the gate electrode; A method of manufacturing a liquid crystal display device having a top gate thin film transistor structure comprising forming a pixel electrode on the interlayer insulating film. The method of claim 1, And the active layer and the gate electrode are formed through a single process. The method according to claim 1 and 2, And said interlayer insulating film is formed of an organic insulating film by spin-on-glass method. The method according to claim 1 and 2, The common electrode is formed on a plastic substrate. The method of manufacturing a liquid crystal display device having a top gate thin film transistor structure.