KR20130062123A - Resin composition for spacer and method of fabricating cot type array substrate method using the same - Google Patents

Abstract

PURPOSE: A resin composition for a spacer and a fabricating method of a color on a film transistor(COT) type array substrate using the same are provided to simplify manufacturing processes by forming a gap spacer and a column spacer through one mask process. CONSTITUTION: A resin composition for a spacer(151,152) includes a binder resin, a photo initiator, a cross-linker, a carbon black pigment, and an organic black pigment. The carbon black pigment is based on polymeric materials. The organic black pigment is based on low molecular or single molecular materials. The carbon block pigment is a compound with 5000-7000 molecular weights of carbon and an acryl-based resin. The organic black pigment is a compound with 1000 or less of molecular weights of an RGB pigment and an acrylic resin.

Description

RESIN COMPOSITION FOR SPACER AND METHOD OF FABRICATING COT type Array Substrate Method USING the same}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an array substrate, and in particular, when forming a gap spacer and a pressed spacer in a COT structure array substrate on a channel region of an active layer through a mask process, A resin composition for spacers having a ΔH) and a method for manufacturing a CIO structure array substrate using the same.

Flat panel display devices (FPDs) are widely used in portable computers such as notebook computers and PDAs, as well as in portable telephones as well as monitors of desktop computers, in place of conventional cathode ray tube (CRT) It is an electronic information display device essential for realizing a lightweight system. Currently commercially available flat panel display devices include liquid crystal displays (LCDs), plasma display panels (PDPs), organic light emitting diodes (OLEDs), and the like. However, liquid crystal displays (LCDs) are now in the spotlight because of mass production technology, ease of driving means, realization of high image quality, and realization of a large area screen.

2. Description of the Related Art Generally, a liquid crystal display device includes a liquid crystal panel in which liquid crystal material is injected between two substrates, in which two substrates each having electrodes for generating an electric field are disposed to face each other, By controlling an optical anisotropy and a birefringence characteristic of the liquid crystal molecules by an electric field generated by the liquid crystal molecules. Therefore, in the manufacturing process of the liquid crystal display, the bonding process of two substrates on which two electrodes are formed has a great effect on image quality, and a color on TFT (COT) structure has been proposed to improve defects due to bonding errors.

1 is a view showing the structure of a conventional COT structure liquid crystal display device.

As shown in the drawing, a conventional COT structure liquid crystal display device includes a lower substrate 11 and an upper substrate 21.

A gate electrode 12 made of a conductive material such as a metal is formed on the lower substrate 11, and a gate insulating layer 13 made of silicon nitride (SiNx) or silicon oxide (SiO 2) is formed on the gate electrode 12. Covering (12).

An active layer 14 made of amorphous silicon is formed on the gate insulating layer 13 to overlap the gate electrode 12, and an ohmic contact layer 15 made of amorphous silicon doped with impurities is formed thereon.

A source electrode 16a and a drain electrode 16b made of a conductive material such as a metal are formed on the ohmic contact layer 15. The source and drain electrodes 16a and 16b are formed together with the gate electrode 12. The transistor T is formed.

Although not shown, the gate electrode 12 is connected to the gate line, the source electrode 16a is connected to the data line, and the gate line and the data line cross each other to define the pixel area.

A protective film 17 is formed on the entire surface of the lower substrate 11 including the source and drain electrodes 16a and 16b to protect the thin film transistor T, which is formed of a silicon nitride film, a silicon oxide film, or an organic insulating film.

The black matrix 23 is formed on the passivation layer 17 at a position corresponding to the thin film transistor T. The black matrix 23 is formed on the entire surface of the substrate with an opening in a portion corresponding to the pixel electrode 20. Therefore, the black matrix 23 prevents light leakage caused by the tilting of the liquid crystal molecules in portions other than the pixel electrode 20, and also blocks light from entering the channel portion of the thin film transistor T. It serves to prevent the light leakage current from occurring.

The color filter 22 is formed in the pixel area above the passivation layer 17. In the color filter 22, R, G, and B colors are sequentially arranged, and one color corresponds to one pixel area. . The color filter 22 should be formed so as not to remain in the portion corresponding to the drain electrode 16b to be exposed through the contact hole 28. Further, on the color filter 22, a planarization film 26 made of an inorganic insulating film such as silicon oxide or silicon nitride or an organic insulating film such as acrylic resin or BCB is formed. The flattening film 26 improves the step by the color filter 22 and prevents the liquid crystal from being contaminated.

A contact hole 28 is formed through the planarization film 26 and the protective film 17 to expose the drain electrode 16b. The pixel electrode 30 made of a transparent conductive material electrically connected to the drain electrode 16b is formed in the pixel area of the contact hole 28 and on the planarization layer 26. The column spacer 50 is formed on a portion of the planarization layer 26 corresponding to the thin film transistor T.

In addition, a transparent upper substrate 21 spaced at a predetermined interval by the column spacer 50 is disposed on the lower substrate 11. The upper substrate 21 is formed with a common electrode 23 made of a transparent conductive material.

In the state where the lower substrate 11 and the lower substrate 21 are bonded together, liquid crystal is injected between the pixel electrode 30 and the common electrode 23. The liquid crystal molecules of the liquid crystal include the pixel electrode 30 and the common electrode ( When voltage is applied to 23), the image is displayed by changing the arrangement state by the generated electric field.

In the liquid crystal display device having the above structure, the column spacer 50 is formed by a conventional photolithography process, and one more mask process is required to form the column spacer 50. In contrast, the manufacturing cost increases.

In order to improve the above-mentioned disadvantages, a method of omitting the lower black matrix and forming the column spacer 50 into the black matrix pattern using the black resin has been proposed. However, the column spacer 50 includes a gap spacer that maintains a gap between substrates and a pressure spacer that prevents deformation when pressure is applied to the substrate, and the spacer spacer has a height higher than that of the gap spacer. When the black resin is used, the amount of light is not properly absorbed according to the high optical density characteristic, and thus, the required height difference between the gap and the pressed spacer in the exposure process using one halftone mask ( There is a limit to forming to have ΔH).

That is, the spacer resin is used to form the column spacer. As the carbon black colorant is added to the spacer resin to serve as a black matrix, the optical density is increased to increase the amount of resin. Absorption of more than a certain portion does not occur. Therefore, since the light transmittance is low in the wavelength band where the resin is exposed, the amount of light is not transmitted to an appropriate depth, making it difficult to form a height difference ΔH between the gap spacer and the pressed spacer. In addition, in order to increase the light transmittance of the resin by reducing the content of the carbon black colorant in order to increase the amount of light absorbed in the resin, there is a problem that can not play a role of the black matrix properly.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and an array substrate for a CIO structure liquid crystal display device in which a black column spacer serving as a black matrix in a COT structure liquid crystal display device is formed on a thin film transistor through one mask process. And the purpose is to provide a method for producing the same.

In order to achieve the above object, the resin composition for a spacer according to an embodiment of the present invention, the binder resin (binder regin), photo initiator (cross-linker), carbon black pigment (carbon black pigment) And a resin composition for spacers comprising an organic black pigment, wherein the carbon black colorant is made of a high molecular material, and the organic black colorant is made of a low molecular or monomolecular material.

The carbon black colorant is characterized in that the molecular compound is a compound of carbon (Carbon) and acrylic resin (acrylic resin) of 5000 to 7000 or less.

The organic black colorant is a compound of an RGB colorant having a molecular weight of 1,000 or less and an acrylic resin.

The binder resin is characterized by being an epoxy acrylate (Epoxy Acrylate) having a molecular weight of 5000 or more and 7000 or less.

The photoinitiator is characterized in that the oxime (Oxime) -based compound.

In order to achieve the above object, a method of manufacturing a CIO structure array substrate using a resin composition for spacers according to a preferred embodiment of the present invention, forming a thin film transistor, a color filter and a pixel electrode on the substrate; Forming a photoresist film including a carbon black colorant made of a polymer material and an organic black colorant made of a single molecule or a low molecular material on the entire surface of the substrate on which the pixel electrode is formed; And forming a black column spacer and a pressed spacer using a halftone mask.

Forming a thin film transistor, a color filter, and a pixel electrode on the substrate may include preparing a substrate; Forming a gate electrode, a gate wiring, and a common wiring on the substrate; Sequentially forming a gate insulating film, an amorphous silicon thin film, a first conductive film, and a photosensitive film on the substrate; Selectively patterning the photoresist to form a photoresist pattern; Patterning the first conductive layer using the photoresist pattern as a mask to form an active pattern, a source electrode, a drain electrode, and a data wiring; Forming a protective film; Forming a color filter layer and a planarization layer on the passivation layer; Forming first and second contact holes exposing the drain electrode and one region of the common wiring; And forming a second conductive layer on the substrate, forming a pixel electrode connected through the drain electrode and the first contact hole using a mask, and forming a common electrode connected through the second contact hole. Characterized in that.

The carbon black colorant is characterized in that the compound is a compound of the carbon (Carbon) and acrylic resin (acrylic resin) of 5000 to 7000 or less.

The organic black colorant is a compound of an RGB colorant having a molecular weight of 1,000 or less and an acrylic resin.

According to the spacer resin composition of the present invention and a method for manufacturing a CIO structure array substrate using the same, the patterning process occurs by separating the upper and lower layers during vacuum drying by forming a material in the material of the black column spacer into a polymer material and a single molecule material. It is possible to easily control the height difference ΔH between the column spacers according to the exposure exposure time.

Accordingly, in the method of manufacturing the array substrate, the gap spacer and the column spacer serving as the black matrix can be formed through one mask process, thereby reducing the manufacturing cost and simplifying the process.

1 is a view showing the structure of a conventional COT structure liquid crystal display device.
2 is a plan view illustrating a partial region of an array substrate for a liquid crystal display according to an exemplary embodiment of the present invention.
3A to 3E are cross-sectional views illustrating a process sequence of the present invention cut along the II 'and II-II' portions of FIG. 2.
4A and 4B illustrate a process of forming a column and a pressed spacer in an array substrate manufacturing method according to an exemplary embodiment of the present invention.

Hereinafter, an array substrate for a CIO structure liquid crystal display device and a method of manufacturing the same according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

2 is a plan view illustrating a partial region of an array substrate for a liquid crystal display according to an exemplary embodiment of the present invention.

As shown in the drawing, the gate wiring 104 extending in one direction on the substrate 100, the common wiring 106 formed in parallel with the gate wiring 104, and the pixel region crossing the gate wiring 104 perpendicularly. The data line 116 defining P is formed.

The thin film transistor T composed of the gate electrode 102, the semiconductor layer 108, the source electrode 112, and the drain electrode 114 is formed at the point where the gate wiring 104 and the data wiring 116 intersect. The gate electrode 102 may be formed to protrude from the gate wiring 104, and the source electrode 114 may be formed to protrude from the data wiring 116.

A color filter 122 is formed in the pixel region P to implement R, G, and B colors, and a pixel in contact with the drain electrode 114 of the thin film transistor T is disposed on the color filter 122. The electrode wiring 130 is formed. In addition, the common electrode wiring 136 is formed to face the pixel wiring electrode 130. The pixel electrode wiring 130 and the common electrode wiring 136 described above extend in a direction facing each other to form the pixel electrode 131 and the common electrode 137 that form an electric field. In the drawing, an example of a bending structure in which the pixel electrode 131 and the common electrode 127 described above are bent is illustrated.

In addition, a gap spacer 151 and a pressure spacer 152 alternately formed on the upper portion of each of the thin film transistors T, which serve as a black matrix, which blocks the light.

Here, the gap spacers 151 are formed more in number than the pressure spacers 152 when viewed as the entire array substrate.

As illustrated, the array substrate for a COT structure liquid crystal display device according to the present invention includes a color filter 122, and the array substrate 100 intersects with one side of each pixel area P defined on one surface thereof. A gate wiring (not shown) and a data wiring 116 are formed on the other side of the direction, and the gate electrode 102, the active layer 108, the source electrode 112, and the drain electrode 114 are formed at each intersection of the two wirings. A thin film transistor (T) including a) is formed.

In addition, the color filter 122 is disposed in the pixel region P. In general, red, green, and blue color filters may be formed in various forms. In the drawing, an example of a stripe pattern in which the same color filter is formed in the pixel area P positioned in the vertical direction is illustrated, but may be arranged to have another shape.

A flattening film (not shown) is formed above the color filter 122 to planarize the surface of the color filter 122, and the thin film transistor T is formed for each pixel region P only on the top of the flattening film. The pixel electrode wiring 130 in contact with the drain electrode 114 and the first contact hole 128 is formed.

In this case, since signal interference between the pixel electrode wiring 130 and the lower data wiring 116 may be minimized by the lower color filter and the planarization layer, the adjacent gate wiring and the adjacent gate wiring may be patterned when the pixel electrode wiring 130 is patterned. It is formed extending over the data lines 104 and 116.

This configuration has a feature that the opening area can be further enlarged as compared with the prior art.

In addition, opaque column spacers 151 and 152 that function as black matrix as light blocking means are formed on the upper portion corresponding to each thin film transistor T.

The above-described column spacers are made of a black resin material having or without photosensitization of the gap spacer 151 and the pressing spacer 152, and thus the active layer 108 of the thin film transistor T is exposed from incident light. ), And also may simultaneously maintain a gap of the array substrate 100 and the corresponding upper substrate (not shown).

Hereinafter, a method of manufacturing an array substrate for a COT structure liquid crystal display device according to an exemplary embodiment of the present invention will be described with reference to a process cross-sectional view of the array substrate of the COT structure liquid crystal display device having the planar structure described above.

3A to 3E are cross-sectional views illustrating a process sequence of the present invention taken along lines II ′ and II-II ′ of FIG. 2.

First, as shown in FIG. 3A, a gate electrode (104 in FIG. 2) extending in one direction of the substrate 100 and a gate electrode extending from the gate wiring by depositing and patterning a conductive metal on the substrate 100. 102 is formed. Although not shown, common wiring (106 in FIG. 2) is simultaneously formed in this step.

Next, one selected from the group of inorganic insulating materials including silicon nitride (SiNX) and silicon oxide (SiO 2) is deposited on the entire surface of the substrate 100 on which the gate wiring and the gate electrode 102 are formed to form a first insulating layer. The gate insulating film 106 is formed.

Pure amorphous silicon (a-Si: H) and amorphous silicon (n + a-Si: H) containing impurities are deposited and patterned on the gate insulating layer 106 to form a gate insulating layer 106 adjacent to the gate electrode 104. The active layer 108 and the ohmic contact layer 110 are formed on the?

Next, as illustrated in FIG. 3B, chromium (Cr) or molybdenum (Mo) is deposited on the entire surface of the substrate 100 on which the active layer 108 and the ohmic contact layer 110 are formed, and patterned by a mask process. The source electrode 112 and the drain electrode 114 contacting the ohmic contact layer 110, respectively, and the data wiring 116 connected to the source electrode 112 are formed.

The protective layer 118 is formed by depositing one selected from the group of inorganic insulating materials including silicon nitride (SiN 2) and silicon oxide (SiO 2) on the entire surface of the substrate 100 on which the source and drain electrodes 112 and 114 are formed.

In this case, the function of the passivation layer 118 serves to prevent a surface defect that may occur between the column spacer and the active layer 108 formed later.

Next, as shown in FIG. 3C, the dye for forming the color filter is coated on the passivation layer 118 and then patterned to form the color filters 122a, 122b, and 122c. Here, the color filters 122a, 122b, and 122c may be formed by applying a photosensitive color resin and then patterning them. Usually, red, green, and red are used as patterns, and full color is displayed by mixing these colors. It becomes possible.

Next, as shown in FIG. 3D, the planarization film 126 is formed on the entire surface of the substrate 100 on which the color filters 122a, 122b, and 122c are formed. The planarization layer 126 may be formed by selecting an organic insulating material. Examples of the planarization film 126 may include benzocyclobutene (BCB) and acrylic resin.

Next, the planarization layer 126 is patterned to form a first contact hole 128 exposing a portion of the drain electrode 114. At this time, although not shown, the second contact hole 138 exposing the common wiring 106 (see FIG. 2) is simultaneously formed.

3E, a transparent conductive metal group including indium tin oxide (ITO) and indium zinc oxide (IZO) is formed on the entire surface of the substrate 100 on which the planarization film 126 is formed. One is deposited and patterned to form the pixel electrode wiring 130 and the pixel electrode 131 in contact with the drain electrode 114. At the same time, the common electrode wiring and the common electrode are also formed.

In addition, a carbon black pigment having a molecular weight of several thousand or more and a low molecular organic black pigment having a molecular weight of several thousand or less are uniform on the entire surface of the substrate 100 on which the pixel electrode 130 is formed. The resin composition is mixed and patterned to form a columnar black column spacer 150 at each upper portion of the thin film transistor T.

Here, the resin composition described above is composed of a binder resin, a photo initiator, a cross-linker, a carbon black pigment, and an organic black pigment. In particular, the carbon black colorant is made of a high molecular material, the organic black colorant is characterized in that made of a low molecular or monomolecular material.

As one example, the binder resin is an epoxy acrylate (Epoxy Acrylate) having a molecular weight of 5000 or more and 7000 or less, the photoinitiator may be used an oxime-based compound.

In addition, the carbon black colorant is a compound of carbon and acrylic resin (acrylic resin) with a molecular weight of 5000 or more and 7000 or less, The organic black colorant is used by a compound of an RGB colorant and an acrylic resin having a molecular weight of 1000 or less. Can be.

At this time, as shown in Figure 4a, the carbon black colorant and the organic black colorant is uniformly dispersed in the resin coating step on the planarization layer 126, the organic black colorant is moved upward by the vacuum drying process, As the carbon black colorant moves downward, the upper and lower layer separation occurs between the polymer and the low molecular weight material.

Herein, the organic black colorant, which is a low molecular or monomolecular material, has wavelength bands having high light absorption according to R, G, and B colors, and the upper layer of the dried resin composition has high light absorption characteristics to control patterning degree. It becomes easy.

In the subsequent soft baking, exposure and development processes, since the low molecular material is disposed on the upper portion, as shown in FIG. 4B, the blocking region M1 for blocking all of the irradiated light and the first transmission for transmitting all the irradiated light are shown. Through the halftone mask M formed of the region M2 and the second transmission region M3 that transmits a part of light by blocking a part of the light by applying a slit pattern, the gap spacer 151 is negatively formed. Gap spacers 151 are formed on the corresponding portions to have a first height h1, and portions corresponding to the pressed spacers 152 are pressed to have a second height h2 by partially irradiating light. The spacer 152 is formed, and light is completely blocked at portions where the spacer is not formed to remove the applied resin.

Here, the height difference (? H) of the gap spacer 151 and the pressing spacer 152 is formed to be at least 0.6um to have a light density characteristic of 0.6 / um.

Accordingly, the black gap and the pressing spacers 151 and 152 which serve as a function of blocking the light from being irradiated to the active layer 108 and a function of maintaining the gap between the two substrates are combined into one. It is formed through a mask process.

Many details are set forth in the foregoing description but should be construed as illustrative of preferred embodiments rather than to limit the scope of the invention. Therefore, the invention should not be construed as limited to the embodiments described, but should be determined by equivalents to the appended claims and the claims.

102 gate electrode 104 gate wiring
106: common wiring 112: source electrode
114: drain electrode 116: data wiring
128: first contact hole 130: pixel electrode wiring
131: pixel electrode 136: common electrode wiring
137: common electrode 151: column spacer
152: pressed spacer

Claims (9)

A resin composition for spacers comprising a binder resin, a photo initiator, a cross-linker, a carbon black pigment, and an organic black pigment,
The carbon black colorant is made of a high molecular material, the organic black colorant is a resin composition for a spacer made of a low molecular or monomolecular material. The method of claim 1,
The carbon black colorant,
Resin composition for a spacer, characterized in that the molecule is a compound of carbon (Carbon) and acrylic resin (acrylic resin) of 5000 to 7000 or less. The method of claim 1,
The organic black colorant,
A resin composition for spacers, characterized in that the compound is an RGB colorant having a molecular weight of 1000 or less and an acrylic resin. The method of claim 1,
Binder resin is epoxy acrylate (Epoxy Acrylate) of the molecular weight 5000 or more and 7000 or less, The resin composition for spacers characterized by the above-mentioned. The method of claim 1,
The photoinitiator is a resin composition for a spacer, characterized in that the oxime-based compound. As a method of manufacturing a CIO structure array substrate,
Forming a thin film transistor, a color filter, and a pixel electrode on the substrate;
Forming a photoresist film including a carbon black colorant made of a polymer material and an organic black colorant made of a single molecule or a low molecular material on the entire surface of the substrate on which the pixel electrode is formed; And
Forming a black column spacer and a pressed spacer using a halftone mask
Method for manufacturing a CIO structure array substrate using a resin composition for spacer comprising a. The method according to claim 6,
Forming a thin film transistor, a color filter and a pixel electrode on the substrate,
Preparing a substrate;
Forming a gate electrode, a gate wiring, and a common wiring on the substrate;
Sequentially forming a gate insulating film, an amorphous silicon thin film, a first conductive film, and a photosensitive film on the substrate;
Selectively patterning the photoresist to form a photoresist pattern;
Patterning the first conductive layer using the photoresist pattern as a mask to form an active pattern, a source electrode, a drain electrode, and a data wiring;
Forming a protective film;
Forming a color filter layer and a planarization layer on the passivation layer;
Forming first and second contact holes exposing the drain electrode and one region of the common wiring; And
Forming a second conductive layer on the substrate, forming a pixel electrode connected through the drain electrode and the first contact hole using a mask, and forming a common electrode connected through the second contact hole;
Method for manufacturing a CIO structure array substrate using a resin composition for spacers comprising a. The method according to claim 6,
The carbon black colorant,
A method for manufacturing a CIO structure array substrate using a resin composition for spacers, characterized in that the molecule is a compound of carbon and carbon resin of 5000 or more and 7000 or less. The method according to claim 6,
The organic black colorant,
A method for producing a CIO structure array substrate using a resin composition for spacers, characterized in that the compound is an RGB colorant having a molecular weight of 1000 or less and an acrylic resin.

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