KR20120127317A - Color filter having polarizing function and method of manufacturing thereof - Google Patents

Abstract

PURPOSE: A color filter and a manufacturing method thereof are provided to secure a display effect while reducing time and costs by omitting a polarizing piece adhesion process. CONSTITUTION: A black matrix(21) is formed on a substrate(1). A polarizing structure(8) is integrally formed on a layer same as the black matrix. The polarized light structure has a plurality of sub pixels. The plurality of sub pixels is located on the black matrix and is separated each other. The polarized light structure comprises a grating pattern of nanoscale which is parallelly arranged. A color filter layer(4) is formed in the upper direction or lower direction of the black matrix and the polarizing structure. A protective layer is formed in the upper direction of the color filter layer. A transparent common electrode layer is formed in the upper direction of the protective layer.

Description

Color filter having a polarizing function and a method of manufacturing the same

TECHNICAL FIELD The present invention relates to a liquid crystal display device, and more particularly, to a color filter and a manufacturing method thereof.

Thin Film Transistor Liquid Crystal Display (TFT-LCD) is the mainstream of current flat panel displays, and has advantages such as low efficiency, relatively low cost, and little radiation. The principle that the TFT-LCD displays is that when the electric field is applied, the transmittance is changed by changing the arrangement of the liquid crystal molecules using the dielectric anisotropy and the conductive anisotropy of the liquid crystal molecules.

The TFT-LCD panel is constructed by combining a color filter substrate and an array substrate facing each other. Shown in FIG. 1 is a cross-sectional view of a color filter in the prior art. In the production process of a TFT-LCD, the said color filter is manufactured using the following method normally. First, a metal layer for forming a black matrix (BM) 2 is formed on the glass substrate 1, one layer of photoresist (Photo Resistance, PR) is applied to the upper surface of the metal layer, and then a photoresist The photoresist pattern layer is exposed to form a photoresist pattern layer, and the black resist 2 is formed by etching the photoresist pattern layer as a mask. Next, the color filter layer 4, the protective layer 5, the transparent common electrode 6, and the spacer 7 are sequentially formed in the above configuration. Since the color filter formed by the said process does not have a polarizing function, it is necessary to further attach the polarization fragment which has a polarizing function to the outer side of a glass substrate. The manufacturing process of such a color filter is relatively complicated and takes a lot of time.

The technical problem to be solved by the present invention is to simplify the manufacturing process of the color filter to lower the manufacturing cost.

In order to solve the above technical problem, an embodiment of the present invention comprises the steps of forming an intermediate layer including a conductive material on the substrate; Forming a photoresist on the intermediate layer; Forming the photoresist into a photoresist pattern having a nanoscale grating pattern; Etching the lower intermediate layer using a photoresist pattern having the nanoscale grating pattern, and forming the intermediate layer into a polarization structure having a black matrix and a grating pattern; to provide.

Another embodiment of the invention is a substrate; And a black matrix formed on the substrate, wherein the polarization structure of the same layer as the black matrix is further formed on the substrate, and the polarization structure includes a plurality of regions (cells) spaced apart from each other, and arranged in parallel on a nanoscale. It provides a color filter having a polarizing function having a grating pattern.

According to the present invention, by forming a photoresist pattern having a nanoscale grating pattern, a black matrix is formed after etching the lower intermediate layer (for example, a metal layer or a resin layer) using the photoresist pattern as a mask. At the same time, a polarizing structure having a polarizing function is further formed in the intermediate layer forming the black matrix. Therefore, the display effect of the display device can be secured, and the process of attaching the polarization pieces can be omitted, thereby saving process time and reducing costs.

1 is a schematic diagram showing the structure of a conventional color filter.
2 is a schematic cross-sectional view of a color filter having a polarizing function according to an embodiment of the present invention.
3 is a plan view of a black matrix and a polarizing structure according to an embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, the specific embodiment of this invention is described in detail, combining a figure and an Example. The following examples are provided to illustrate the present invention and do not limit the scope of the present invention.

The manufacturing method of the color filter which concerns on the Example of this invention has the following steps.

Step 1: Form one intermediate layer for forming a black matrix on the substrate.

The substrate may be a glass substrate, a quartz substrate or a plastic substrate. The intermediate layer is a metal layer in this embodiment, for example, an aluminum layer, a chromium layer, a gold layer or a silver layer. The intermediate layer may be a resin layer containing a conductive material. The conductive material may be a nanoscale metal wire, for example, a silver wire or an aluminum wire or the like, or a metal powder-like additive such that a polarizing structure formed later has a constant electronic characteristic. This intermediate layer is used to form a black matrix (BM) in a subsequent process.

Step 2: Form one layer of photoresist in the intermediate layer.

Step 3: A photoresist pattern having a nanoscale grating pattern is formed using the photoresist.

For example, a nano imprint process can be employed. In other words, a nanoimprint is performed on the photoresist by employing a mold having a nanoscale grating pattern prepared in advance. The mold is manufactured by a grating pattern composed of parallelly arranged slots required for polarization in advance. After nanoimprinting the photoresist, the grating pattern is printed corresponding to a region other than the black matrix of the photoresist. The mold may be manufactured using quartz, glass or plastic.

Step 4: The photoresist pattern having the nanoscale grating pattern is etched with respect to the intermediate layer as a mask, and the intermediate layer is formed into a polarizing structure having a black matrix and the grating pattern.

Dry etching is preferable as the etching in this step. Wet etching or other etching may be used.

The obtained black matrix and polarizing structure are formed in a glass substrate. The polarization structure is provided with a plurality of cells, each located in a pixel region determined by a black matrix, and these pixel regions form an array and are separated from each other at the same time. In the case of the grating polarizer, that is, in the case of the polarization structure in this embodiment, the main structural parameters are the grating period, the grating duty and the depth of the grating. Among them, the (TM transmittance and extinction ratio) key parameter that determines the grating performance is the relationship between the grating period and the incident light wavelength. If the grating period is larger than the incident light wavelength, the grating generates diffracted waves of multiple orders, in which case the grating can be used as a diffraction grating but not as a polarizer. When the grating period is smaller than the incident light wavelength, the grating generates only the diffraction wave of zero order so that the polarization is strong, so that the TM polarization is transmitted and the TE polarization is reflected and can be used as a good polarizer. In this embodiment, the grating period of the grating pattern of the polarizing structure is 60nm-300nm, the grating duty is 0.3-0.7, preferably 0.5, and the depth of the grating is 100nm-200nm, thereby polarizing the visible light. Generates. Therefore, the polarization structure has a polarization function and ensures that the display device finally formed by the color filter can display normally.

In the method, the method further has a step 4 'to form a color filter layer before or after step 4.

If that step 4 'is done before step 4, a color filter layer, for example an RGB sub pixel layer, is placed on the substrate, and the black matrix and polarization structure are located on the color filter. If step 4 'is performed after step 4, the black matrix and the polarizing structure are located on the substrate, and the color filter layer is located on the black matrix and the polarizing structure. The RGB sub pixel corresponds to a sub pixel defined by a black matrix. The formed color filter layer is not limited to a combination such as RGB, but may be a combination of CMYK, for example.

When the step 4 'is performed after the step 4, an overcoat may be further formed on the color filter layer. The material of the protective layer is a resin material, which is used to protect the stepped color filter layer, and is also used to form a flat top surface to form another structural layer.

Moreover, a transparent common electrode layer (for example, ITO Common Electrode) can also be formed in a protective layer. In the case of a liquid crystal display device of Fringe-field Switch (FFS) or In-plane Switch (IPS) type, when the transparent common electrode layer is formed on the array substrate, the transparent common electrode layer is formed on the color filter accordingly. There is no need to form

Post spacers may be further formed in the transparent common electrode layer or the protective layer (when there is no transparent common electrode). Thereby, when the color filter and the array substrate are combined to face each other, the gaps for injecting the liquid crystal are spaced apart using spacers to maintain the cell gap.

In fact, the spacer may be located in the protective layer and penetrated from the transparent common electrode layer. Or it may be located in the color filter layer and penetrate from the protective layer and the transparent common electrode layer. Moreover, it may be located on a glass substrate and penetrate from a black matrix or polarizing structure, a color filter layer, a protective layer, and a transparent common electrode layer.

2 is a schematic view of the structure of the color filter having the polarizing function according to the embodiment of the present invention, and FIG. 3 is a plan view of the black matrix and the polarizing structure according to the embodiment of the present invention. As shown in the figure, the color filter of this embodiment comprises: a substrate 1; A black matrix 21 formed on the substrate 1; And a polarization structure 8 which is the same layer as the black matrix 21 and is preferably integrally formed, wherein the polarization structure 8 is positioned in the black matrix 21 and has a plurality of sub-pixels spaced apart from each other. And grating patterns arranged in parallel on the nanoscale. The color filter layer 4 is formed above or below the black matrix 21 and the polarization structure 8. Each sub pixel of the color filter layer 4 corresponds to a sub pixel partitioned by a black matrix. When the color filter layer 4 is positioned above the black matrix 21, a protective layer 5 may be further formed above the color filter layer 4, and the transparent common electrode layer is disposed above the protective layer 5. (6) is formed. A spacer 7 may be further formed on the substrate 1, the color filter layer 4, the protective layer 5, or the transparent common electrode layer 6.

As shown in the above embodiment, the embodiment of the present invention forms a photoresist pattern having a nanoscale grating pattern, so that the photoresist pattern is used as a mask for a lower intermediate layer (for example, a metal layer or a resin layer). After etching, a polarizing structure having a polarizing function is further formed in the intermediate layer forming the black matrix while forming the black matrix. Therefore, the display effect of the display device can be secured, and the process of attaching the polarization pieces can be omitted, thereby saving process time and reducing costs.

The above description is only an optimal embodiment of the present invention, and those skilled in the art can make some improvements and modifications on the assumption that they do not depart from the technical principles of the present invention, and those improvements and modifications belong to the protection scope of the present invention. It should be stated that it should be considered.

1 board
1, 21 black matrix
4 color filter layer
5 protective layer
6 transparent common electrode layer
7 spacer
8 polarized structure

Claims (15)

As a manufacturing method of a color filter,
Forming an intermediate layer comprising a conductive material on the substrate;
Forming a photoresist on the intermediate layer;
Forming the photoresist into a photoresist pattern having a nanoscale grating pattern;
Etching the lower intermediate layer using a photoresist pattern having the nanoscale grating pattern, and forming the intermediate layer into a polarization structure having a black matrix and a grating pattern;
The manufacturing method of the color filter characterized by including the. The method of claim 1,
The grating pattern of the polarizing structure is a slot arranged in parallel, the grating period of the grating pattern is 60nm-300nm, the grating duty is 0.3-0.7, the depth of the grating is 100nm-200nm Way. The method of claim 2,
The grating duty of the grating pattern of the polarizing structure is 0.5, the manufacturing method of the color filter. 4. The method according to any one of claims 1 to 3,
In Step 3, a photoresist pattern is obtained by employing a mold having a nanoscale grating pattern, performing nanoimprint on the photoresist, and printing the grating pattern corresponding to a region other than the black matrix of the photoresist. The manufacturing method of the color filter characterized by the above-mentioned. 5. The method according to any one of claims 1 to 4,
The intermediate layer has a resin layer containing a metal layer or a conductive material. The method of claim 5,
The conductive material has a nanoscale metal wire or metal powder, the manufacturing method of the color filter characterized by the above-mentioned. 7. The method according to any one of claims 1 to 6,
And a step 4 'to form a color filter layer before or after the step 4. Board;
A color filter having a polarizing function comprising; a black matrix formed on the substrate,
The polarizing structure of the same layer as the black matrix is further formed on the substrate, and the polarizing structure has a plurality of regions spaced apart from each other, and has a polarizing function arranged in parallel on a nano scale. Color filter. 9. The method of claim 8,
The grating pattern of the polarizing structure is a slot arranged in parallel, the grating period of the grating pattern is 60nm-300nm, the grating duty is 0.3-0.7, the depth of the grating is 100nm-200nm characterized in that Color filter. 10. The method of claim 9,
The grating duty of the grating pattern of the polarizing structure is 0.5, the color filter having a polarizing function. 11. The method according to any one of claims 8 to 10,
The material for forming the polarization structure with the black matrix has a resin layer comprising a metal layer or a conductive material. The method of claim 11,
The conductive material has a polarization function, characterized in that the nano-scale metal wire or metal powder. 13. The method according to any one of claims 8 to 12,
And a color filter layer located above or below the black matrix and the polarizing structure. The method of claim 13,
And a protective layer positioned on the color filter layer. 15. The method of claim 14,
And a transparent common electrode layer on the protective layer.

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