KR20050040258A - Method for manufacturing lcd - Google Patents

Abstract

The present invention discloses a method of manufacturing a liquid crystal display device which simplifies the manufacturing process by using a film type protective film when forming a TFT / color filter integrated substrate and forming a color filter and a pixel electrode according to an inkjet method. The disclosed invention comprises the steps of forming a gate bus line by performing a first mask process on a substrate; A gate insulating film, a semiconductor layer for forming a channel layer, and an ohmic contact layer are sequentially applied on the substrate on which the gate bus line is formed, and then a metal film for forming an electrode of the TFT is deposited, and then a second mask process is used. Simultaneously forming a TFT and a data bus line; Forming a protective film on the substrate on which the TFT and the data bus line are formed; Exposing portions other than the pixel region on the substrate on which the protective film is formed, and removing the protective film of the pixel region portion; Forming a color filter layer by sequentially dropping color ink in an area where the protective film is removed; And dropping a transparent material on the color filter layer formed on the substrate to form a pixel electrode.

Description

Liquid crystal display manufacturing method {METHOD FOR MANUFACTURING LCD}

The present invention relates to a method for manufacturing a liquid crystal display device. More particularly, when manufacturing a TFT / color filter integrated substrate, a color filter and a pixel electrode are formed according to an inkjet method to manufacture a liquid crystal display device which can simplify the manufacturing process. It is about a method.

In general, as the modern society changes to the information socialization, the importance of the liquid crystal display module, which is one of the information display devices, is gradually increasing. The CRT (Cathode Ray Tube), which is widely used so far, has many advantages in terms of performance and cost, but has many disadvantages in terms of miniaturization or portability.

On the other hand, although the LCD is somewhat expensive in terms of price, it has advantages such as miniaturization, light weight, thinness, low power, and consumption, and thus has been attracting attention as an alternative means to overcome the disadvantages of the CRT.

The liquid crystal display device has a structure in which an array substrate on which thin film transistors are arranged, and a color filter substrate on which red, green, and blue color filter layers are formed are bonded to each other with a liquid crystal interposed therebetween.

In particular, the structure of the array substrate has a gate bus line for applying a driving signal and a data bus line for applying a graphic signal vertically arranged to define a unit pixel area on a transparent glass substrate, and a switching operation is performed on each unit pixel area. TFT and an ITO pixel electrode are arranged.

A pad region is formed on the edge regions of the gate bus line and the data bus line to apply a signal. The pad region is applied to a pixel region in which drive signals and graphic signals generated from a PCB substrate are formed in a matrix form.

The array substrate and the color filter are manufactured by etching the metal film and the insulating layer according to a predetermined mask process. The manufacturing process of the array substrate is as follows.

First, a first mask process of depositing and etching a metal film on a transparent glass substrate to form a gate bus line and a gate electrode, followed by applying a gate insulating film, an amorphous silicon film, and a doped amorphous silicon film to form a channel layer. A second mask process, a source / drain metal film is deposited on the substrate on which the channel layer is formed, and then a third mask process of etching to form source / drain electrodes and data bus lines, and then a protective film is applied to protect the device. A fourth mask process for forming a contact hole and a five-mask process for depositing and etching an ITO transparent metal film on the substrate on which the protective film is formed to form a pixel electrode.

A black matrix is formed on a transparent glass substrate in a manner similar to the above-described array substrate manufacturing process, and R, G, and B color filters are sequentially formed on each active region to produce a color filter substrate. Bonded to manufacture a liquid crystal display device.

Recently, a technique for reducing a mask process by integrally manufacturing an array substrate and a color filter substrate of a liquid crystal display device on a single glass substrate has been developed.

1A to 1G are views illustrating a TFT / color filter integrated liquid crystal display substrate manufacturing process according to the prior art.

As shown in FIG. 1A, a gate metal is deposited on a transparent glass substrate 10 by sputtering on the entire region of the substrate, and a photoresist, which is a photosensitive material, is coated on the gate metal film. Then, it is exposed and developed to form the gate electrode 1 and the gate bus line.

Then, a gate insulating film 3 is coated on the substrate on which the gate electrode 1 and the gate bus line are formed.

As shown in FIG. 1B, when the gate insulating film is applied onto the substrate on which the gate electrode and the gate bus line are formed, the amorphous silicon film, the doped amorphous silicon film and the metal film are continuously deposited, and then the photoresist is deposited. The source and drain electrodes 9a and 9b, the channel layer 5 and the data bus line 7 are simultaneously formed using a halftone mask (diffraction exposure).

In this case, unlike the 5 mask process, an amorphous silicon film and a doped amorphous silicon film exist under the data bus line 7.

Although not shown in the drawings, reference numeral 6 is an ohmic contact layer.

When the source / drain electrodes 9a are formed and the TFT is completed, as shown in FIG. 1C, the protective film 11 is coated on the entire area of the substrate 10 and then as shown in FIG. 1D. R, G, and B color resins are sequentially formed on a substrate to which (11) is applied according to a known pigment spraying method to form color filter layers 17a, 17b, and 17c.

At this time, a part of the color filter layer formed in the TFT region is etched for the contact hole process of punching the protective film 11 on the drain electrode 9b of the TFT, and the data bus line 7 and the channel layer 5 of the TFT are etched. The color filter layer is etched to form a black matrix (15) in the region.

After the R, G, and B color filter layers 17a, 17b, and 17c are formed as described above, a resin material is coated on the TFT channel layer 6 and the data bus line 7, and then etched to form a black matrix ( Complete 15).

The position of the black matrix 15 is formed between the source electrode 9a and the drain electrode 9b of the TFT and in a portion overlapping with the data bus line 7 and the gate bus line (not shown).

When the black matrix 15 is completed on the substrate 10 as described above, as shown in FIG. 1E, the organic layer 20 is applied onto the substrate 10 on which the black matrix 15 is formed. The organic layer 20 is generally coated on the entire region of the substrate using a photo acryl material, which is an overcoat material of the liquid crystal display.

Then, as shown in FIG. 1F, when the organic layer 20 is applied on the substrate 10, the organic layer 20 is contacted by a dry etching process to pierce the drain region of the TFT and electrically contact the pixel electrode 30. Form a hole.

When the contact hole is formed as described above, when the contact hole is formed as illustrated in FIG. 1G, an ITO metal film is deposited on the entire area of the substrate 10 and etched to complete the pixel electrode 30.

However, if the TFT / color filter-integrated substrate is formed according to the above process, too many mask processes are performed on one substrate, and the manufacturing cost is high, and each process produces a high possibility of generating foreign substances and defective dimensions. There is a problem of poor yield.

In addition, since the color filter layer is formed by the pigment spraying method, a protective film must be used over the entire area of the substrate for the protection of the TFT device.

In addition, due to various metal films, insulating films, R, G, B color resins, photoacryl, and exposure and development operations according to the respective processes on one substrate, impurity concentrations are very high, resulting in a high defect rate.

An object of the present invention is to provide a liquid crystal display device manufacturing method which can reduce a mask process by applying a film type protective film and forming a color filter and a pixel electrode according to an inkjet method when manufacturing a TFT / color filter integrated substrate. There is this.

In order to achieve the above object, the liquid crystal display device manufacturing method according to the present invention,

Performing a first mask process on the substrate to form a gate bus line;

A gate insulating film, a semiconductor layer for forming a channel layer, and an ohmic contact layer are sequentially applied on the substrate on which the gate bus line is formed, and then a metal film for forming an electrode of the TFT is deposited, and then a second mask process is used. Simultaneously forming a TFT and a data bus line;

Forming a protective film on the substrate on which the TFT and the data bus line are formed;

Exposing portions other than the pixel region on the substrate on which the protective film is formed, and removing the protective film of the pixel region portion;

Forming a color filter layer by sequentially dropping color ink in an area where the protective film is removed; And

And dropping a transparent material on the color filter layer formed on the substrate to form a pixel electrode.

Here, the protective film is a thermally opaque film or an opaque film or a transparent film, the removal of the protective film is exposed by laser irradiation, then removed, the area where the protective film is removed on the substrate is the drain electrode of the TFT It is characterized in that it extends from this exposed edge part to a pixel area | region.

The color filter layer is formed on the pixel region from which the protective film is removed. The color filter ink is placed in an inkjet printer header and dropped on the pixel region. The color filter layer is a drain of the TFT exposed from the gate insulating layer. It has a thickness below an electrode.

In addition, a method of forming a pixel electrode formed on the color filter layer is formed by inserting a conductive transparent material into an inkjet printer header and dropping the ink in a form of ink, wherein the conductive transparent material is a material made of a conductive polymer or a PEDOT material, and the pixel electrode The thickness of 50 nm-2 micrometers, It is characterized by the role of the black matrix of a color filter substrate, when the said protective film is opaque.

According to the present invention, in manufacturing a TFT / color filter integrated substrate, a film type protective film is attached, the film is removed by laser irradiation, and color filters and pixel electrodes are formed in an inkjet method to simplify the manufacturing process while Can be reduced.

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

2A to 2H illustrate a process of manufacturing a TFT / color filter integrated liquid crystal display substrate according to the present invention.

As shown in FIG. 2A, a gate metal film is deposited on the transparent glass substrate 100 by sputtering on the entire region of the substrate, and a photoresist, which is a photosensitive material, is coated on the gate metal film, followed by exposure and development. Thus, the gate electrode 101 and the gate bus line are formed.

Thereafter, a gate insulating layer 103 is coated on the substrate 10 on which the gate electrode 101 and the gate bus line are formed.

Then, as shown in FIG. 2B, a gate insulating film 103 is coated on the substrate 100 on which the gate electrode 101 and the gate bus line are formed, and then an amorphous silicon film, a doped amorphous silicon film, and a metal film are formed. After successive application, the source / drain electrodes 109a and 109b of the TFT are formed by a halftone mask or a diffraction exposure method used in a four mask process, and at the same time, the channel layer 105 and the ohmic contact layer 106 of the TFT are formed. ) And data bus line 107.

When the TFT is completed according to the two mask process as described above, as shown in Fig. 2C, the protective film 111 is formed on the entire region of the substrate on which the TFT is completed.

The protective film 111 may be an opaque or transparent film as a thermal transfer film, but in order to remove the mask process for forming a black matrix, a protective film 111 of an opaque material is used.

When the protective film 111 is attached to the substrate as described above, as shown in FIG. 2D, the irradiated portion is irradiated by irradiating an area outside the region where the pixel electrode on the substrate 100 is to be formed by laser exposure. Leave the part and remove the rest (Thermal Imaging Transfer).

When the protective film 111 is an opaque material, a mask process for forming a black matrix on the TFT region and the data bus line 107 may not be performed after laser exposure, but the protective film 111 is transparent. In the case of a material, an additional process of forming a black matrix is performed.

In the region where the protective film 111 is removed by the laser exposure, a portion of the drain electrode 109b of the TFT must be exposed for electrical contact with the pixel electrode formed in the subsequent process. From the partial region to the pixel region where the pixel electrode is to be formed.

When the protective film 111 is etched as described above, as shown in FIGS. 2E and 2F, the R, G, and B color filter layers 120 in a liquid form are formed according to the inkjet method.

The inkjet method forms an R, G, and B color filter layer 120 by dropping an inkjet print head 200 dropping ink on the pixel area.

 As described above, when the R, G, and B color filter layers 120 are formed on the pixel area of the substrate, as shown in FIGS. 2G and 2H, a conductive polymer (eg, PEDOT) may be used to form the pixel electrode. A liquid transparent metal is formed on the R, G, and B color filter layers 120 using an inkjet method to form the pixel electrode 130.

In this case, the pixel electrode 130 is formed while the conductive polymer dropped on the R, G, and B color filter layers 120 is filled, wherein the pixel electrode 130 is formed of the drain electrode 109b of the TFT. You will be in direct contact with some.

Accordingly, a contact hole forming process for electrically connecting the pixel electrode 130 and the electrodes 109a and 109b of the TFT is unnecessary.

In addition, the thickness of the pixel electrode 130 formed by the inkjet method is in a range of 50 nm to 2 μm, and a mask process that has been conventionally performed to form the pixel electrode 130 can be reduced.

That is, in the present invention, when manufacturing the TFT / color filter integrated substrate, there is no additional mask process after the two mask process for forming the TFT, so that the color filter layer and the TFT array substrate can be manufactured by the two mask process as a whole. There is this.

As described in detail above, the present invention reduces manufacturing costs while simplifying the manufacturing process by attaching a film type protective film and forming a color filter and a pixel electrode according to an inkjet method when manufacturing a TFT / color filter integrated substrate. It can be effective.

The present invention is not limited to the above-described embodiments, and various changes can be made by those skilled in the art without departing from the gist of the present invention as claimed in the following claims.

1A to 1G illustrate a TFT / color filter integrated liquid crystal display substrate manufacturing process according to the prior art.

2A to 2H illustrate a process of manufacturing a TFT / color filter integrated liquid crystal display substrate according to the present invention.

* Description of the symbols for the main parts of the drawings *

100 substrate 101 gate electrode

103: gate insulating film 105: channel layer

106: ohmic contact layer 107: data bus line

109a and 109b: source / drain electrodes 111: protective film

120: color filter layer 130: pixel electrode

Claims (10)

Performing a first mask process on the substrate to form a gate bus line; A gate insulating film, a semiconductor layer for forming a channel layer, and an ohmic contact layer are sequentially applied on the substrate on which the gate bus line is formed, and then a metal film for forming an electrode of the TFT is deposited, and then a second mask process is used. Simultaneously forming a TFT and a data bus line; Forming a protective film on the substrate on which the TFT and the data bus line are formed; Exposing portions other than the pixel region on the substrate on which the protective film is formed, and removing the protective film of the pixel region portion; Forming a color filter layer by sequentially dropping color ink in an area where the protective film is removed; And And dropping a transparent material on the color filter layer formed on the substrate to form a pixel electrode. The method of claim 1, The protective film is a thermal transfer film, an opaque film or a transparent film, characterized in that the manufacturing method of the liquid crystal display device. The method of claim 1, The removal of the protective film is exposed by laser irradiation, and then removed. The method of claim 1, And a region where the protective film is removed on the substrate is from an edge portion at which the drain electrode of the TFT is exposed to a pixel region. The method of claim 1, And forming a color filter layer on the pixel region from which the protective film is removed. The color filter ink is placed in an inkjet printer header and dropped onto the pixel region. The method of claim 1, And the color filter layer has a thickness less than or equal to the drain electrode of the TFT exposed from the gate insulating film. The method of claim 1, The method of forming a pixel electrode formed on the color filter layer may include forming a conductive transparent material in an inkjet printer header and dropping the same in an ink form. The method of claim 7, wherein The conductive transparent material is a liquid crystal display device manufacturing method characterized in that the material of the conductive polymer or PEDOT material. The method of claim 1, The pixel electrode has a thickness of 50nm ~ 2㎛ manufacturing method of the liquid crystal display device. The method according to claim 1 or 2, If the protective film is opaque, the liquid crystal display device manufacturing method characterized in that it serves as a black matrix of the color filter substrate.