KR101023317B1 - Manufacturing method of liquid crystal display device - Google Patents

Abstract

The present invention relates to a method for manufacturing a liquid crystal display device. According to an aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device, comprising: forming a black matrix on a substrate; Forming a color filter layer with a first colored layer, a second colored layer, and a third colored layer between the patterned gaps of the formed black matrix, respectively; Forming an overcoat layer on the formed color filter layer; It is characterized in that it comprises the step of forming a common electrode on the overcoat layer.

In the manufacturing method of the liquid crystal display device according to the present invention, in the manufacturing method of the color filter using the organic BM, it is possible to minimize the step according to the color filter layer and the organic BM process without reducing the height of the thick organic BM.

Black matrix, color filter layer, organic material

Description

Manufacturing method of liquid crystal display device {FABRICATION METHOD FOR LCD}

1A to 1D are views illustrating a procedure of a method of manufacturing a color filter of a liquid crystal display according to the related art.

2A to 2D are diagrams illustrating a method of manufacturing a liquid crystal display device having a COT structure according to the related art.

3A and 3B illustrate a generation of steps between a black matrix and a color filter layer according to the related art.

4A to 4D illustrate an embodiment of a method of manufacturing a color filter of a liquid crystal display according to the present invention.

5A to 5D illustrate an embodiment of a method of manufacturing a liquid crystal display device having a COT structure according to the present invention.

6A to 6D illustrate an embodiment of a method of manufacturing a liquid crystal display device having a TOC structure according to the present invention.

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

41, 51, 70 --- Board 42, 60, 72 --- Black Matrix

43, 59, 71 --- color filter layer 44, 61, 73 --- overcoat layer

45 --- Common electrode

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a liquid crystal display device, and in particular, a method of manufacturing a color filter using an organic black matrix, in which a step according to the color filter layer and the organic BM process is minimized without reducing the height of the thick organic black matrix. It relates to a color filter manufacturing method that can be done.

Recently, liquid crystal displays have been spotlighted as next generation advanced display devices having low power consumption, good portability, technology-intensive, and high added value.

Among such liquid crystal display devices, an active matrix liquid crystal display device having a switching element capable of controlling voltage on / off for each pixel is attracting the most attention due to its excellent resolution and video performance.

In general, a liquid crystal display device forms an array substrate and a color filter substrate through an array substrate manufacturing process for forming a switching element and a pixel electrode and a color filter substrate manufacturing process for forming a color filter and a common electrode, respectively. It completes through the liquid crystal cell process through a liquid crystal between them.

The driving principle of the liquid crystal display device uses the optical anisotropy and polarization property of the liquid crystal. Since the liquid crystal is thin and long in structure, the liquid crystal has directivity in the arrangement of molecules, and the direction of the molecular arrangement can be controlled by artificially applying an electric field to the liquid crystal.

Accordingly, when the molecular arrangement direction of the liquid crystal is arbitrarily adjusted, the molecular arrangement of the liquid crystal is changed, and light is refracted in the molecular arrangement direction of the liquid crystal due to optical anisotropy to express image information.

In the liquid crystal display device, the color filter substrate and the thin film transistor array substrate are fabricated through different processes and bonded to each other.

In addition, in order to simplify the manufacturing process of the above-described liquid crystal display device, a so-called 'Color Filter on TFT (COT)' method or 'TFT on color' which forms a color filter on a thin film transistor array substrate. The new concept of the filter (TFT on Color Filter) method is also applied.

1A to 1D are views illustrating a procedure of a method for manufacturing a color filter of a liquid crystal display according to the related art. First, as shown in FIG. 1A, after cleaning the glass substrate 11, an organic material is deposited and patterned using a mask to form the black matrix 12.

On the other hand, the black matrix 12 is formed by replacing the organic material by Cr metal is environmentally regulated.

Subsequently, as shown in FIG. 1B, after the black matrix 12 is formed, the first, second, and third colored layers of red, green, and blue may be formed to realize color. The color filter layer 13 is patterned using a color resist.

In this case, the first, second, and third colored layer patterns overlap the black matrix 12 with each other to form a process margin.                         

Subsequently, an overcoat layer 14 is formed on the formed color filter layer 13 to planarize the black matrix 12.

In more detail, each color layer is formed to overlap the portion where the black matrix 12 is formed in order to bring a wide margin in the process.

As illustrated in FIG. 1C, the overcoat layer 14 is formed using an acrylic resin or the like for protecting and planarizing the colored pattern.

At this time, the overcoat layer 14 is formed to a sufficient thickness so that the step due to the overlapping portion of the colored layers on the black matrix 12 can be solved.

Finally, as shown in FIG. 1D, the common electrode 15 for operating the liquid crystal cell is formed on the overcoat layer 14 together with the pixel electrode formed on the TFT substrate.

That is, indium tin oxide (ITO), which is a transparent electrode material having good permeability and conductivity and excellent chemical and thermal stability, is deposited on the entire surface of the overcoat layer 14 by sputtering.

2A to 2D illustrate a method of manufacturing a liquid crystal display device having a COT structure according to the related art. As shown in the drawing, in the liquid crystal display of the COT structure, after forming a thin film transistor as a switching element, a red, green, and blue colored layer is formed on the thin film transistor. Is produced by.

First, as shown in FIG. 2A, a gate electrode 22 is formed on the transparent substrate 21, and a gate insulating film 23 is grown on the gate electrode 22 by plasma enhanced chemical vapor deposition (PECVD). Let's do it.

Next, an amorphous silicon layer doped with amorphous silicon and phosphorus is patterned by photolithography after deposition to form an active layer 24 and an ohmic contact layer 25.

The source / drain electrodes 26a and 26b and the data line are formed by etching the source / drain electrodes 26a and 26b and the mask of the data line on the amorphous silicon layer.

Thereafter, the protective film 27 is formed using the inorganic film.

As shown in FIG. 2B, the color filter layers 29 of red, green, and blue are formed on the thin film transistors formed in the pixel areas, respectively.

In more detail, the color filter layer 29 may be formed by a dye method, an electrodeposition method, a pigment dispersion method, a print method, or the like.

In addition, when the red, green, and blue color resins are sequentially formed, the R, G, and B color patterns overlap each other to form a process margin.

Subsequently, as shown in FIG. 2C, the black matrix 30 is formed on the formed color filter layer 29. In this case, the black matrix 30 is formed in a portion where the respective color resins overlap, and is formed to have a thickness to represent an appropriate level of optical density (OD).

In addition, the material forming the black matrix 30 is preferably made of black resin, which is an opaque organic material under Cr metal environmental regulation.

Subsequently, as shown in FIG. 2D, an overcoat layer 31 is formed on the formed black matrix 30, and then a pixel electrode 28 is formed of indium titan oxide (ITO).

That is, the material constituting the overcoat layer 31 is an organic or inorganic material, and particularly preferably an organic material having excellent planarization characteristics. Such organic materials include BCB (benzocyclobutene) and acrylic resins.

3A and 3B illustrate a generation of steps between a black matrix and a color filter layer according to the related art. 3A illustrates a step generated when a color filter layer is formed after a black matrix is formed on a substrate by the manufacturing process of FIGS. 1A to 1D, and FIG. 3B illustrates the manufacturing process of FIGS. 2A to 2D. The step that occurs when the black matrix is formed after the color filter layer is formed on the substrate is shown.

The black matrix formed by using the organic material in the above manner cannot be reduced because the thickness of the black matrix has to be formed relatively thick to obtain a large optical density (OD) value due to the characteristics of the organic material.

Meanwhile, in forming the R, G, and B color filter layers, the step becomes larger as the R, G, and B color patterns overlap each other for process margin.                         

Therefore, in order to overcome the step between the black matrix formed of the organic material and the color filter layer, the overcoat layer is also formed relatively thick, thereby causing a problem of transmittance loss.

The present invention provides a method of manufacturing a color filter using an organic black matrix, wherein the thickness of the overcoat layer is minimized in order to overcome the step of the color filter layer and the organic black matrix process without reducing the height of the thick organic black matrix. It is an object of the present invention to provide a color filter manufacturing method capable of improving transmittance.

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

Patterning and forming a black matrix on the substrate;

Forming a color filter layer with a first colored layer, a second colored layer, and a third colored layer between the patterned gaps of the formed black matrix, respectively;

Forming an overcoat layer on the formed color filter layer;

It is characterized in that it comprises the step of forming a common electrode on the overcoat layer.

In particular, the black matrix is characterized in that it is formed of an organic material.

In particular, the black matrix and the color filter layer are characterized in that the thickness is formed at a similar height.                     

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

Forming thin film transistors in pixel regions on the substrate, respectively;

Forming a color filter layer by separating the first colored layer, the second colored layer, and the third colored layer from each other at predetermined intervals on the thin film transistors respectively formed in the pixel region;

Forming a black matrix between the first color layer, the second color layer, and the third color layer of the formed color filter layer spaced apart from each other by a predetermined interval;

It is characterized in that it comprises the step of forming an overcoat layer on the formed black matrix.

In particular, the forming of the thin film transistor may include sequentially forming a gate electrode, a gate insulating layer, an active layer, an ohmic contact layer, a source / drain electrode, a data line, and a protective layer on a transparent substrate. It has that feature.

In particular, the method may further include forming a common electrode on the overcoat layer using a transparent conductive film (Indium Titan Oxide: ITO).

In particular, the black matrix is characterized in that the first colored layer, the second colored layer, and the third colored layer are formed wider than spaced apart from each other at a predetermined interval.

In particular, the black matrix is characterized in that it is formed of an organic material.                     

In particular, the black matrix and the color filter layer are characterized in that the thickness is formed at a similar height.

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 color filter layer by separating the first colored layer, the second colored layer, and the third colored layer from each other at predetermined intervals in the pixel region;

Forming a black matrix between the first color layer, the second color layer, and the third color layer of the formed color filter layer spaced apart from each other by a predetermined interval;

Forming an overcoat layer on the formed black matrix;

And a step of forming thin film transistors in the pixel areas on the formed overcoat layer, respectively.

In particular, the forming of the thin film transistor may include sequentially forming a gate electrode, a gate insulating film, an active layer, an ohmic contact layer, a source / drain electrode, a data line, a protective film, and a common electrode on a transparent substrate. Its features are that it forms.

According to the present invention, in the manufacturing method of the color filter using the organic black matrix, it is possible to minimize the step according to the color filter layer and the organic black matrix process without reducing the height of the thick organic black matrix.

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

4A to 4D illustrate an embodiment of a method of manufacturing a color filter of a liquid crystal display according to the present invention. As shown in FIG. 4A, after cleaning the glass substrate 41, an organic material is deposited and patterned using a mask to form the black matrix 42.

On the other hand, the black matrix 42 is formed by replacing the organic material with Cr metal is environmentally regulated.

Subsequently, as shown in FIG. 4B, after the black matrix 42 is formed, the color filter layer 43 is patterned by using a color resist to implement color.

That is, a red first colored layer is applied at the height of the black matrix 42 formed by patterning on the substrate. And after exposing only the specific area | region of the said 1st colored layer apply | coated using a mask, partial exposure is performed.

In this case, the first colored layer is patterned so as not to overlap the black matrix 42.

Then, the first colored layer whose photochemical structure is changed by exposure is dipped in a developing solution to develop the first colored layer pattern, and the developed photosensitive film is cured to form a red color (hereinafter referred to as R color).

In general, since the colored layer has the characteristics of a negative resist, the unexposed portion is removed.

In addition, the processes of forming the red color are repeatedly performed to sequentially form the second colored layer and the third colored layer pattern colored in green and blue, respectively.                     

In this case, the first, second, and third colored layer patterns are formed in such a manner as to fill the gaps between the patterns on which the black matrix 42 is formed, and are formed by the thickness of the black matrix 42 formed of the organic material.

Subsequently, as shown in FIG. 4C, an overcoat layer 44 is formed on the formed color filter layer 43 to planarize the black matrix 42 and the color filter layer 43.

In more detail, in order to protect and planarize the colored pattern, the overcoat layer 44 is formed by a spin coating method using an acrylic resin or a polyimide resin.

In this case, since the step between the color filter layer 43 and the black matrix 42 does not occur, the overcoat layer 44 may be formed as thin as possible to minimize loss of transmittance.

Finally, as shown in FIG. 4D, the common electrode 45 for operating the liquid crystal cell is formed on the overcoat layer 44 together with the pixel electrode formed on the TFT substrate.

That is, indium tin oxide (ITO), which is a transparent electrode material having good permeability and conductivity and excellent chemical and thermal stability, is deposited on the entire surface of the overcoat layer 44 by sputtering.

5A to 5D are diagrams illustrating a method of manufacturing a liquid crystal display device having a COT structure according to the present invention. As shown in the drawing, the liquid crystal display of the COT structure forms a thin film transistor as a switching element and then forms red, green, and blue color resins on the thin film transistor. Is produced in a way.

First, as shown in FIG. 5A, a gate electrode 52 is formed on a transparent substrate 51, and a gate insulating layer 53 is grown on the gate electrode 52 by plasma enhanced chemical vapor deposition (PECVD). Let's do it.

Next, an amorphous silicon layer doped with amorphous silicon and phosphorus is patterned by a photolithography process after deposition to form an active layer 54 and an ohmic contact layer 55.

The source / drain electrodes 56a and 56b and the data lines (not shown) are etched by etching the source / drain electrodes 56a and 56b and masks of the data lines (not shown) on the amorphous silicon layer. Is formed.

Thereafter, the protective film 57 is formed using the inorganic film.

As shown in FIG. 5B, a color filter layer 59 of red, green, and blue, which is the first, second, and third colored layers, is formed on the formed thin film transistor.

In more detail, the color filter layer 59 may be formed by a dye method, an electrodeposition method, a pigment dispersion method, a print method, or the like.

In addition, when the red, green, and blue colored layers are sequentially formed, spaces between the colored layers are spaced at predetermined intervals to provide a space for forming the black matrix 60 later. do.                     

At this time, the predetermined interval is narrower than the width of the black matrix 60 to be formed later.

Subsequently, as shown in FIG. 5C, a black matrix 60 is formed on the formed color filter layer 59. In addition, the black matrix 60 may be formed between the respective colored layers, and formed wider than the spaced space, thereby covering the edge due to the pattern of the colored layer, thereby solving the stain.

In addition, the material forming the black matrix 60 is preferably made of black resin, which is an opaque organic material, under the environmental control of Cr metal.

Subsequently, as shown in FIG. 5D, an overcoat layer 61 is formed on the formed black matrix 60.

That is, the material constituting the overcoat layer 61 is an organic or inorganic material, and particularly preferably an organic material having excellent planarization characteristics. Such organic materials include BCB (benzocyclobutene) and acrylic resins.

In this case, since the step between the color filter layer 59 and the black matrix 60 does not occur, the overcoat layer 61 may be formed as thin as possible to minimize the loss of transmittance.

The common electrode 58 is formed of indium titanium oxide (ITO) on the formed overcoat layer.

6A to 6D illustrate an embodiment of a method of manufacturing a liquid crystal display device having a TOC structure according to the present invention. As shown in FIG. 6A, a color filter layer 71 of red, green, and blue is formed on the substrate 70.

In more detail, the color filter layer 71 may be formed by a dye method, an electrodeposition method, a pigment dispersion method, a print method, and the like, in particular, a pigment dispersion method. It is preferable that it is formed by.

In addition, when the red, green, and blue colored layers are sequentially formed, spaces between the colored layers are spaced at predetermined intervals, respectively, to provide a space for forming the black matrix 72 later. do.

In this case, the predetermined interval is narrower than the width of the black matrix 72 to be formed later.

Subsequently, as shown in FIG. 6B, a black matrix 72 is formed on the formed color filter layer 71. In addition, the black matrix 72 may be formed between the respective colored layers, and may be formed wider than the spaced space to cover the edges due to the pattern of the colored layer.

In addition, the material forming the black matrix 72 is preferably made of black resin, which is an opaque organic material, under the environmental control of Cr metal.

Subsequently, as shown in FIG. 6C, an overcoat layer 73 is formed on the formed black matrix 72.

That is, the material forming the overcoat layer 73 is an organic or inorganic material, and in particular, an organic material having excellent planarization characteristics is preferable. Such organic materials include BCB (benzocyclobutene) and acrylic resins.

In this case, since the step between the color filter layer 71 and the black matrix 72 does not occur, the overcoat layer 73 may be formed as thin as possible to minimize the loss of transmittance.

Subsequently, as shown in FIG. 6D, a gate electrode 74 is formed on the substrate on which the overcoat layer 73 is formed, and the gate is formed on the gate electrode 74 by plasma enhanced chemical vapor deposition (PECVD). The insulating film 75 is grown.

Next, an amorphous silicon layer doped with amorphous silicon and phosphorus (phosphorus) is patterned by deposition after photolithography to form an active layer 76 and an ohmic contact layer 77.

The source / drain electrodes 78a and 78b and the data line (not shown) are etched by etching the source / drain 78a and 78b electrodes and the mask of the data line (not shown) on the amorphous silicon layer. Is formed.

Subsequently, a passivation layer 79 is formed using an inorganic layer, and a common electrode 80 is formed of indium titanium oxide (ITO) on the passivation layer 79.

Therefore, as applied in the so-called 'Color Filter on TFT' method of forming a color filter on the thin film transistor array substrate, the TFT is formed on the color filter. The process of forming the color filter may also be applied to a manufacturing method of an on color filter (hereinafter, referred to as a 'TOC' method).                     

As described above in each of the above embodiments, in using the black matrix of a thick organic material, the step between the color filter layer and the black matrix process may be solved and the thickness of the overcoat layer may be lowered.

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 color filter manufacturing method according to the present invention, in the manufacturing method of the color filter using the organic black matrix, the step according to the color filter layer and the organic black matrix process without reducing the height of the thick organic black matrix. It can be minimized.

Claims (10)

delete delete Forming thin film transistors in pixel regions on the substrate, respectively; Forming a color filter layer by separating a first colored layer, a second colored layer, and a third colored layer from each other on the pixel region where the thin film transistors are formed at predetermined intervals; The black matrix having the same height as the first, second, and third colored layers between the first color layer, the second color layer, and the third color layer of the formed color filter layer, spaced apart from each other at predetermined intervals. Forming a; And forming an overcoat layer on the formed black matrix. The method of claim 3, wherein The forming of the thin film transistor may include sequentially forming a gate electrode, a gate insulating layer, an active layer, an ohmic contact layer, a source / drain electrode, a data line, and a protective layer on a transparent substrate. Method of manufacturing a liquid crystal display device. The method of claim 3, wherein And forming a common electrode on the overcoat layer using a transparent conductive film (Indium Titan Oxide: ITO). Forming a color filter layer by separating the first colored layer, the second colored layer, and the third colored layer from each other at predetermined intervals in the pixel region; Forming a black matrix between the first color layer, the second color layer, and the third color layer of the formed color filter layer spaced apart from each other by a predetermined interval; Forming an overcoat layer on the formed black matrix; And forming thin film transistors in the pixel areas on the formed overcoat layer, respectively. The method of claim 6, The forming of the thin film transistor may include sequentially forming a gate electrode, a gate insulating layer, an active layer, an ohmic contact layer, a source / drain electrode, a data line, a protective layer, and a common electrode. Method of manufacturing a liquid crystal display device. The method according to claim 3 or 6, wherein And the black matrix is formed to be wider than the first colored layer, the second colored layer, and the third colored layer spaced apart from each other at predetermined intervals. The method according to claim 3 or 6, wherein And the black matrix is formed of an organic material. The method of claim 6, And the black matrix and the color filter layer are formed at the same height.

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