KR20050001783A - A liquid crystal display and the fabricating method - Google Patents

Abstract

PURPOSE: An LCD(Liquid Crystal Display) and a manufacturing method thereof are provided to form a column spacer for maintaining a cell gap to an outer portion having a sealing member printed thereon for bonding upper and lower substrates, thereby capable of maintaining the cell gap. CONSTITUTION: A gate line and a data line are crossed with each other and arrayed on the lower substrate(31). A gate electrode(32) is extended from the gate line. A gate insulating layer(33) is formed at the entire surface of the substrate including the gate electrode. A semiconductor layer(34) is formed on the gate insulating layer. A TFT(Thin Film Transistor) comprised of source/drain electrodes(35/36) is formed on the semiconductor layer. A pixel electrode(38) is connected to the drain electrode of the TFT through a contact hole formed at a passivation film(37). A black matrix pattern(40) for blocking the transmission of light toward the region except for the pixel electrode is formed on an upper substrate(31a). RGB color filter patterns(39) for displaying colors are formed on the black matrix pattern. A common electrode(41) is formed on the color filter patterns. Column spacers(42,44) for maintaining a cell gap constantly between the upper and lower substrates. A seal member(43) for sealing the upper and lower substrates is printed and thereafter a bond process is performed.

Description

Liquid crystal display and its manufacturing method {A LIQUID CRYSTAL DISPLAY AND THE FABRICATING METHOD}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device and a method of manufacturing the same. In particular, the cell gap of the outer portion is uniform by forming column spacers to maintain the cell gap in the outer portion where the seal material for bonding the upper and lower plates of the liquid crystal display device is printed. It relates to a liquid crystal display device and a method of manufacturing the same that can be maintained.

In recent years, the need for a flat panel display has emerged in order to meet the times of thinning, weight reduction, and low power consumption. Accordingly, a thin film transistor type liquid crystal display device (hereinafter referred to as TFT-LCD) having excellent color reproducibility and thinness has been developed.

In general, a liquid crystal display (LCD) displays an image corresponding to a data signal on a panel by adjusting light transmittance of liquid crystal cells arranged in a matrix form on a liquid crystal panel with a video data signal supplied thereto. do.

At present, the rapid development and application of the TFT-LCD industry have inevitably required an increase in size and an increase in resolution, and a lot of efforts have been made in view of simplification of manufacturing process and improvement of yield in order to increase productivity. .

The liquid crystal display is largely divided into a TFT process, a color filter process, and an LCD module process. The TFT process is a process of manufacturing a TFT substrate, which is a deposition process and a photo-etching process. The gate wiring, the data wiring, the thin film transistor and the pixel electrode are disposed on the insulating substrate through the) process.

The color filter process is a process for manufacturing a color filter substrate, and after forming a color filter pattern of red (R), green (G), and blue (B) using a dye or a pigment on an insulating substrate, It is a process of forming indium tin oxide (ITO) for electrodes.

In the LCD module process, after bonding the TFT substrate and the color filter substrate to maintain a constant cell gap, liquid crystal is injected, and a circuit portion for various signal processing, an LCD panel, and a circuit portion for signal processing are mounted. It is a process to do it.

1 is a cross-sectional view of a conventional liquid crystal display device. As shown in the drawing, the conventional liquid crystal display device has a structure in which two insulating substrates (hereinafter, referred to as 'top plate' and 'bottom plate') are opposed to each other and a liquid crystal is enclosed therebetween. A gate wiring and a data wiring intersected with each other, a gate electrode 2 extending from the gate wiring, a gate insulating film 3 formed on the entire surface including the gate electrode 2, and the gate insulating film 3. A thin film transistor (TFT) including a semiconductor layer 4 formed thereon and a source / drain electrode 5/6 formed on the semiconductor layer 4 is formed, and is formed through a contact hole formed in the protective layer 7. The pixel electrode 8 is connected to the drain electrode 6 of the thin film transistor.

A black matrix pattern 10 is formed on the top plate to block light from being transmitted to regions other than the pixel electrode 8, and color filters of red, green, and blue to express colors on the black matrix 10 are provided. The pattern 9 is formed, and the common electrode 11 is formed on the color filter pattern 9.

In addition, a spacer 14 is disposed between the upper plate 1a and the lower plate 1 to maintain a constant cell gap, and a seal material is printed to seal the upper plate 1a and the lower plate 1. After that, a step of bonding is performed.

FIG. 2 is a diagram illustrating printing a general seal material along a seal line. FIG. As shown therein, the seal pattern has two functions of forming a gap for injecting liquid crystal and not leaking the injected liquid crystal. The seal pattern is a step of uniformly forming a thermosetting resin into a desired pattern. Generally, a dispenser printing method and a screen printing method are used.

Meanwhile, the sealant 13 serves as a spacer by mixing and using glass fibers 12 for maintaining a cell gap.

Then, the seal material is patterned, and the liquid crystal is injected through the liquid crystal injection hole. In this case, the liquid crystal is injected by a vacuum injection method using a pressure difference between the inside and outside of the cell.

After the liquid crystal is injected, if the liquid crystal injection hole is sealed with an encapsulant so that the injected liquid crystal does not flow out, the conventional manufacturing of the liquid crystal display panel is completed.

However, in the process of actually forming the seal pattern, the uniformity of the thickness and height of the seal gap is a very important process control item.

Therefore, when the sealant mixed with the glass fiber is used as described above, if the mixing ratio or the distribution of the glass fiber is unevenly formed, the cell gap becomes inconsistent after curing of the seal pattern, resulting in problems such as poor seal bursting. .

The present invention provides a liquid crystal display device in which the cell gap of the outer portion can be uniformly maintained by forming a column spacer to maintain the cell gap in the outer portion where the seal material for bonding the upper plate and the lower plate of the liquid crystal display device is printed. The purpose is to provide a method.

1 is a cross-sectional view of a conventional liquid crystal display device.

2 is a diagram illustrating printing a common seal material along a seal line.

3 is a view schematically showing the structure of a liquid crystal display according to the present invention;

4 is a view schematically illustrating a structure of a color filter substrate on which column spacers of a liquid crystal display according to the present invention are formed.

5A to 5D are diagrams showing a procedure for a method of manufacturing a liquid crystal display device according to the present invention.

<Description of the symbols for the main parts of the drawings>

401 --- Substrate 402 --- Black Matrix

403 --- color filter layer 404 --- common electrode

405 --- Column spacer

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

A black matrix formed on the transparent insulating substrate at predetermined intervals;

Color filter layers of R, G, and B formed for color expression in the space between the black matrices;

A common electrode formed on the color filter layer;

It is characterized in that it comprises a column spacer formed in the active region and the seal region defined on the common electrode.

Here, in particular, the height of the column spacer formed in the active region and the seal region defined above is characterized by being formed by the cell gap.

In addition, the liquid crystal display device according to the present invention in order to achieve the above object,

A color filter substrate on which a color filter defined by an active region and a seal region is formed;

A column spacer formed in the active region and the seal region on the color filter substrate;

A thin film transistor substrate having thin film transistors (TFTs), each of which functions as a switching element, at a crossing point of a gate bus line and a data bus line at a position corresponding to an active region of the color filter substrate;

In order to bond the color filter substrate and the thin film transistor substrate, it is characterized in that it includes a bonding seal material printed on the seal region in which the column spacer is formed.

Here, in particular, the seal material is characterized in that a thermosetting or UV (ultraviolet) curable epoxy resin is used.

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

Forming a black matrix on the transparent insulating substrate;

Sequentially forming a color filter layer of red color, green color, and blue color on the formed black matrix;

Depositing a transparent conductive film on the formed color filter layer to form a common electrode;

It is characterized in that it comprises the step of forming a column spacer in the active region and the seal region defined on the formed common electrode.

In particular, the column spacer formed in the active region and the seal region defined above is characterized in that the height is determined by the cell gap.

Here, in particular, the step of printing the adhesive seal material along the seal line on the column spacer formed in the seal area;

After the step of printing the adhesive seal material along the seal line on the column spacer formed in the seal region, the step of bonding the thin film transistor substrate corresponding to the substrate is characterized in that it further comprises.

According to the present invention, the cell gap of the outer portion can be uniformly maintained by forming column spacers to maintain the cell gap in the outer portion where the seal material for bonding the upper and lower plates of the liquid crystal display device is printed.

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

3 is a view schematically showing the structure of a liquid crystal display according to the present invention. As shown in the drawing, the liquid crystal display device using the column spacer according to the present invention has a structure in which liquid crystal is enclosed between two insulating substrates (hereinafter, referred to as 'top plate' and 'bottom plate'). Gate wirings and data wirings intersected with each other are formed at 31, and a gate electrode 32 extending from the gate wiring, a gate insulating film 33 formed on the entire surface including the gate electrode 32, and the gate insulating film. A thin film transistor (TFT) including a semiconductor layer 34 formed on the 33 and a source / drain electrode 35/36 formed on the semiconductor layer 34 is formed, and a contact hole formed in the passivation layer 37. The pixel electrode 38 connected to the drain electrode 36 of the thin film transistor is formed through the pixel electrode 38.

A black matrix pattern 40 is formed on the upper plate to block light from being transmitted to regions other than the pixel electrode 38, and red, green, and blue colors for expressing colors on the black matrix pattern 40. The filter pattern 39 is formed, and the common electrode 41 is formed on the color filter pattern 39.

In addition, column spacers 42 and 44 are formed between the upper plate 31a and the lower plate 31 to maintain a constant cell gap, and the seal member 43 to seal the upper plate 31a and the lower plate 31. ) Is printed and then bonded.

4 is a diagram schematically illustrating a structure of a color filter substrate on which column spacers of a liquid crystal display according to the present invention are formed. As shown therein, the color filter substrate on which the column spacer is formed includes: a black matrix 402 formed on the transparent insulating substrate 401; A color filter layer 403 of R, G, and B formed for color expression in a space between the black matrices 402; A common electrode 404 formed of an ITO transparent conductive film on the color filter layer 403; And a column spacer 405 formed in the active region and the seal region defined on the common electrode 404.

5A to 5D are diagrams showing the procedure for the manufacturing method of the liquid crystal display device according to the present invention. Here, the manufacturing method of the liquid crystal display according to the present invention includes a dyeing method, a dye dispersion method, a pigment dispersion method, an electrodeposition method and the like, but the pigment dispersion method will be described as an example.

First, as shown in FIG. 5A, a black matrix 402 is formed by depositing a metal film or a resin material on the transparent insulating substrate 401.

More specifically, a photosensitive film made of carbon black, titanium oxide, or the like having light shielding property is applied onto the transparent substrate 401, and the photosensitive film is exposed to a predetermined pattern using a mask. Then, the photosensitive film is developed according to the exposed pattern, and the developed photosensitive film is cured to form a black matrix (BM) 402.

Subsequently, as shown in FIG. 5B, the color filter layer 403 of red color R, green color G, and blue color B is sequentially formed on the formed black matrix 402. Perform.

In more detail, a photosensitive film made of an azo red pigment or the like is coated on the transparent substrate 401 on which the BM 402 is formed, and the photosensitive film is exposed to a predetermined pattern using a mask.

Then, the photosensitive film is developed in accordance with the exposed pattern, and the developed photosensitive film is cured to form a red color (hereinafter referred to as R color).

Subsequently, a photosensitive film made of protarocyanine-based green pigment or the like is applied onto the transparent substrate on which the R color is formed, and the photosensitive film is exposed to a predetermined pattern using a mask. Then, the photosensitive film is developed in accordance with the exposed pattern, and the developed photosensitive film is cured to form a green color (hereinafter referred to as G color).

Subsequently, a photoresist film made of phthalocyanine-based blue pigment or the like is cured on the transparent substrate on which the G color is formed to form a blue color (hereinafter referred to as B color) to complete the color filter layer 403.

Subsequently, as shown in FIG. 5C, an ITO (Indium Tin Oxide) film, which is a transparent conductive film, is deposited on the formed color filter layer 403 to form a common electrode 404. Perform.

As shown in FIG. 5D, a column spacer 405 is formed in the active region and the seal region defined on the formed common electrode 404.

More specifically, the division of the active region and the seal region defined above defines an inner region of the seal pattern as the active region around the seal pattern, and defines a portion in which the seal pattern is formed as the seal region.

The column spacer 405 is coated with a black resin-based organic resin material on the color filter layer 403 and patterned at regular intervals through an exposure and development process.

Here, the column spacer 405 serves to maintain a gap of the liquid crystal cell.

Meanwhile, as described above, the substrate on which the column spacer is formed is subjected to a process in which the seal material is printed to bond with another substrate (not shown). At this time, the seal material is printed on the column spacer formed in the seal area to maintain the cell gap of the substrate outer portion.

Therefore, it is possible to maintain a uniform cell gap of the liquid crystal display without mixing the glass fiber with the sealant.

The seal pattern on which the seal material is printed has two functions of forming a gap for injecting liquid crystal and not leaking the injected liquid crystal. The seal pattern is a step of uniformly forming a thermosetting resin into a desired pattern. Generally, a dispenser printing method and a screen printing method are used.

The dispenser printing method uses the same principle as the syringe. That is, the sealant is filled in the dispenser and a seal pattern having a desired width and thickness is formed at a predetermined pressure.

Seal pattern formation through the screen printing method is formed by a process of printing a thermosetting sealant on a substrate through a screen, and a drying process of evaporating the solvent contained in the sealant for leveling.

As the seal material used in the seal pattern, a thermosetting or UV (ultraviolet) curable epoxy resin or the like is generally used. However, the epoxy resin itself is harmless to the liquid crystal, but the amine included in the thermosetting agent may decompose the liquid crystal material.

Therefore, in the case of forming the thermosetting epoxy resin seal pattern, it is necessary to sufficiently prebak the sealant while changing the baking temperature step by step after screen printing.

After the seal material is printed, another substrate (thin film transistor substrate) corresponding to the substrate is bonded together, and the liquid crystal is injected through the liquid crystal injection hole. In this case, the liquid crystal is injected by a vacuum injection method using a pressure difference between inside and outside of the sal.

After the liquid crystal is injected, the liquid crystal display is manufactured by encapsulating the liquid crystal injection hole with an encapsulant so that the injected liquid crystal does not flow out.

As described above, in the process of forming the color substrate, the column spacer is formed in the seal region, thereby maintaining a uniform cell gap of the liquid crystal display without mixing a separate glass fiber in the sealant.

Although the present invention has been described with reference to the embodiments illustrated in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

As described above, the liquid crystal display device and the manufacturing method thereof according to the present invention, by forming a column spacer to maintain the cell gap in the outer portion where the seal material for bonding the upper plate and the lower plate of the liquid crystal display device by forming a cell of the outer cell The gap can be kept uniform.

In addition, the material cost can be reduced by not using a separate glass fiber for the sealant.

Claims (7)

A black matrix formed on the transparent insulating substrate at predetermined intervals; Color filter layers of R, G, and B formed for color expression in the space between the black matrices; A common electrode formed on the color filter layer; And a column spacer formed in the active region and the seal region defined on the common electrode. The method of claim 1, The height of the column spacer formed in the defined active region and the seal region is formed by a cell gap. A color filter substrate on which a color filter defined by an active region and a seal region is formed; A column spacer formed in the active region and the seal region on the color filter substrate; A thin film transistor substrate having thin film transistors (TFTs), each of which functions as a switching element, at a crossing point of a gate bus line and a data bus line at a position corresponding to an active region of the color filter substrate; And a bonding seal material printed on a seal area in which the column spacer is formed to bond the color filter substrate and the thin film transistor substrate. The method of claim 3, wherein The seal material is a liquid crystal display device characterized in that the thermosetting or UV (ultraviolet) curable epoxy (epoxy) resin is used. Forming a black matrix on the transparent insulating substrate; Sequentially forming a color filter layer of red color, green color, and blue color on the formed black matrix; Depositing a transparent conductive film on the formed color filter layer to form a common electrode; Forming column spacers in the active region and the seal region defined on the formed common electrode. The method of claim 5, The column spacer formed in the defined active region and the seal region has a height determined by a cell gap. The method of claim 5, Printing an adhesive seal material along a seal line on a column spacer formed in the seal area; And bonding the thin film transistor substrate corresponding to the substrate after the adhesive seal material is printed along the seal line on the column spacer formed in the seal region.