KR20020017189A - Method for fabricating a color filter substrate - Google Patents

Abstract

PURPOSE: A manufacturing method of a color filter substrate is provided to substitute the glass substrate with a plastic substrate for improving the durability of the liquid crystal display. CONSTITUTION: A manufacturing method of a color filter substrate includes the steps of forming a common electrode(18) on an entire mother substrate, forming black matrix patterns(13) on the common electrode, forming color filter layers(15) between the black matrix patterns, forming an adhesive material(17) to the entire surface including the color filter layers, attaching a plastic substrate(19) on the adhesive material, and removing the mother substrate.

Description

Method for fabricating a color filter substrate

The present invention relates to a method for manufacturing a liquid crystal display device, and more particularly, to a method for manufacturing a color filter substrate using plastic as a substrate material.

With the recent development of new advanced imaging devices such as high definition TVs, liquid crystal displays (LCDs), electroluminescence displays (ELDs), vacuum fluorescence displays (VFDs) and plasma display panels (PDPs) instead of CRTs Research on flat panel display devices such as the like is being actively conducted.

Among them, LCD is a representative technology of flat panel display, which is characterized by thin, low cost, low power consumption, etc., and it is not only used to display lap top computer or pocket computer, but also for vehicle loading and color TV image. In addition, its use is expanding rapidly.

The LCD having such characteristics is arranged such that a color filter substrate, which is an upper substrate, and a TFT (Thin Film Transistor) substrate, which is a lower substrate, are disposed to face each other, and a liquid crystal having dielectric anisotropy is formed therebetween. The TFTs added to the hundreds of thousands of pixels through the selection address wiring are driven to switch voltages to the pixels.

At this time, the color filter substrate is arranged in a predetermined order to implement the color and the black and red light, the role between the red (Green), green (Blue) color filter layer and the R, G, B cells and light blocking The matrix and a common electrode for applying voltage to the liquid crystal cell.

The three colors constituting the color filter layer are driven independently of each other, and a color of one pixel is displayed by the combination thereof.

On the other hand, the method of manufacturing a color filter substrate is a dye method and a pigment method according to the material of the organic filter used in the manufacturing, and may be classified into a dyeing method, dispersion method, coating method, electrodeposition method, inkjet method, etc. At present, the most common method used in the production of the color filter layer of the TFT-LCD is the pigment dispersion method.

Hereinafter, with reference to the accompanying drawings will be described a method for manufacturing a prior art color filter substrate using the pigment dispersion method.

1A to 1F are process diagrams showing a method of manufacturing a color filter substrate according to the prior art.

First, after cleaning the glass substrate 1, as shown in FIG. 1A, a chromium or carbon-based organic material used as the black matrix 3 material is deposited by sputtering.

After the black matrix 3 is formed, a color filter layer is patterned using a color resist to implement color.

That is, as shown in FIG. 1B, a first color resist 4 colored with red is applied to the entire surface including the black matrix 3 so as to completely cover the black matrix 3.

Next, as shown in FIG. 1C, only a specific area of the upper portion of the resist 4 applied using the mask 7 is exposed, followed by partial exposure.

Next, as shown in FIG. 1D, the first color resist 4 whose photochemical structure has been changed by exposure is immersed in a developer to be patterned to form a first colored layer pattern 5a.

In general, the color resist has the characteristics of a negative resist, so that an unexposed part is removed.

The processes shown in FIGS. 1B to 1D are repeatedly performed to form second and third colored layer patterns 5b and 5c colored with green and blue, respectively, as shown in FIG. 1E.

At this time, the mask to be used is used by shifting the same mask used when exposing the first color resist.

Finally, the formation of the common electrode 8 for operating the liquid crystal cell together with the pixel electrode formed on the TFT substrate is made after the color filter layer is formed.

As shown in FIG. 1F, ITO (Indium Tin Oxide), which is a transparent electrode material having good permeability and conductivity and excellent chemical and thermal stability, is deposited on the entire surface including the colored pattern by sputtering. ITO as the common electrode 8 does not form a separate pattern.

For reference, in order to protect and planarize the colored pattern before forming the common electrode, the planarization film may be formed by spin coating using an acrylic resin or a polyimide resin, but the manufacturing process cost may be reduced. May be omitted.

However, the conventional method of manufacturing a color filter substrate as described above has the following problems.

Glass substrates used as conventional color filter substrates are problematic in durability and limited in light weight thinning. In addition, since the existing color filter layer manufacturing process is a high temperature process of more than 150 ℃ it is difficult to apply to plastics.

The present invention has been made to solve the above problems is to provide a method of manufacturing a color filter substrate for producing a color filter substrate without deformation by heat of the plastic substrate in the existing process.

1A to 1F are process drawings showing a method for manufacturing a color filter substrate according to the prior art.

2a to 2e is a process chart showing a manufacturing method of a color filter substrate according to the present invention.

* Explanation of symbols on the main parts of the drawings

11: mosquito board 13: black matrix

15 color filter layer 17 adhesive material

18 common electrode 19 plastic substrate

The method of manufacturing a color filter substrate of the present invention configured as described above includes a process of forming a common electrode on the entire surface of a mother substrate, a process of forming a black matrix pattern on the common electrode, and a color filter layer between the black matrix pattern. And forming a bonding material on the entire surface including the color filter layer, attaching a plastic substrate on the bonding material, and removing the mother substrate.

Hereinafter, a manufacturing method of a color filter substrate according to the present invention will be described in detail with reference to the accompanying drawings.

2a to 2e is a process chart showing a manufacturing method of a color filter substrate according to the present invention.

First, a mother substrate 11 made of glass or metal is prepared and cleaned, and then, as shown in FIG. 2A, ITO, which is a transparent conductive film, is deposited by sputtering to form a common electrode 18. do. However, the mother substrate may be removed by etching or grinding in a subsequent process.

Next, as shown in FIG. 2B, the black matrix 13 is deposited on the common electrode 18 by sputtering, and the portions except the TFT forming portion, the gate and the data wiring portion of the TFT substrate are etched and opened.

In this case, as the material of the black matrix, a metal thin film such as chromium having an optical density of 3.5 or more or a carbon-based organic material is mainly used.

In addition, the color filter layer formed after patterning the black matrix 3 uses a photolithograpy technique using a color resist containing a pigment that realizes color. This includes dyeing, pigment dispersion, coating, electrodeposition, inkjet, and the like.

The pigment dispersion method mainly used will be described in more detail as follows.

The first color resist with red color is applied to the entire surface including the black matrix 13 so as to completely cover the black matrix 13.

The resist coating method includes a spin method and a roll coat method. The spin method is a method in which the resist is evenly spread on the substrate and the substrate is spread evenly throughout the substrate by rotating the substrate at a high speed. The roll coating method is a method of transferring a resist developed on a roll onto a substrate.

After exposing only a specific region on the resist applied using the next mask, partial exposure is performed.

At this time, there are three methods of exposing, including a proximity method for exposing the original to daylight, a stepper method for repeatedly exposing a reduced pattern, and a mirror projection method for projecting and exposing a mask pattern. For example, simple matrix LCDs, which put productivity first, have poor accuracy but fast processing speed, and active matrix LCDs requiring high precision use stepper or mirror projection methods.

Subsequently, when the first color resist whose photochemical structure is changed by immersion is immersed in a developing solution, an unexposed portion is removed to form a desired first colored layer pattern. At this time, the development is any one of dipping, puddle, and shower spray methods.

As the first color layer pattern is formed, the process is repeated to form second and third color layer patterns in which green and blue colors are respectively colored.

Formation of the color filter layer 15 is usually in the order of R, G, and B.

On the other hand, the main components of the color resist is composed of a photopolymerization initiator, a monomer (monomer), a binder (binder) and the like as a general photoresist, an organic pigment for implementing the color.

After the color filter layer is formed in the above manner, the adhesive material 17 is coated on the color filter layer 15 as shown in FIG. 2D, and the plastic substrate 19 is attached to the adhesive material.

Finally, when the mother substrate 11 is removed by etching or grinding, the color filter substrate including the substrate 19 is completed.

For reference, an over-coating process may be added between the process of forming the color filter layer 15 and the process of applying the adhesive material 17, which is a color filter layer formed by the adhesive material 17 when bonding the plastic substrate. It is to prevent the defect of 15) and to flatten the surface on which the adhesive material is to be applied.

The manufacturing method of the color filter substrate of the present invention as described above has the following effects.

In the existing TFT-LCD manufacturing process that includes a high temperature process, not a low temperature process, the glass substrate is replaced with a plastic substrate to form a color filter substrate, thereby improving durability of the liquid crystal display device and realizing light weight thinning.

Claims (4)

Forming a common electrode on the entire surface of the mother substrate; Forming a black matrix pattern on the common electrode; Forming a color filter layer between the black matrix patterns; Forming an adhesive material on the entire surface including the color filter layer; Attaching a plastic substrate on the adhesive material; The method of manufacturing a color filter substrate comprising the step of removing the mother substrate. The method of claim 1, wherein the mother substrate is formed of any one of glass and metal. The method of claim 1, wherein the removing of the mother substrate is performed by etching or grinding. The method of claim 1, wherein an overcoating process is added after the color filter layer is formed.