KR101198219B1 - Array substrate for liquid crystal display device and method of fabricating the same - Google Patents

Abstract

The present invention provides a method of manufacturing a semiconductor device, comprising: forming source and drain electrodes spaced apart from each other on a substrate, and a data line connected to the source electrodes; Forming a pixel electrode in contact with one end of the drain electrode; Continuously forming an organic semiconductor material layer, a gate insulating material layer, a first metal layer, and a second metal layer over the data line, the source and drain electrodes, and the pixel electrode including the spaced apart regions of the source and drain electrodes; Patterning the second metal layer to form a first metal pattern; Dry etching the first metal pattern with an etch mask to form a second metal pattern, a gate insulating film, and an organic semiconductor layer under the same shape as the first metal pattern; Forming a protective layer having a gate contact hole exposing a portion of the first metal pattern over the first metal pattern; A method of manufacturing an array substrate for a liquid crystal display device, the method comprising: forming a gate line over the protective layer and contacting the first metal pattern through the gate contact hole and intersecting the data line.

Organic semiconductor layer, top gate, bottom contact, double layer gate electrode

Description

Array substrate for liquid crystal display device and method of fabricating the same

1 is an exploded perspective view of a general liquid crystal display device.

2 is a cross-sectional view of a switching region of an array substrate for a liquid crystal display device having an organic thin film transistor having a bottom contact structure of a conventional bottom gate.

3 is a cross-sectional view showing one pixel area of an array substrate for a liquid crystal display device having a thin film transistor having a top contact structure of a conventional bottom gate.

4A to 4E are diagrams illustrating a switching element of an array substrate for a liquid crystal display device having an organic semiconductor pattern formed by coating and patterned without damage by an etchant or the like according to the first embodiment of the present invention. Step-by-step process cross-sectional view of the pixel region.

5A to 5F illustrate a switching element of an array substrate for a liquid crystal display device having an organic semiconductor layer formed by coating and patterned without damage by an etchant according to a second embodiment of the present invention. Step-by-step process steps of manufacturing the pixel region P. FIG.

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

201: substrate 210: source electrode

213: drain electrode 217: organic semiconductor layer

225 gate insulating film 230 first metal pattern

232: second metal pattern 233: double layer gate electrode

240: first protective layer 245: gate contact hole

250: gate wiring

P: pixel area op: opening

TrA: switching area

The present invention relates to a liquid crystal display device, and more particularly, to an array substrate for a liquid crystal display device using an organic semiconductor material and a method of manufacturing the same.

In recent years, as the society enters the information age, the display field for processing and displaying a large amount of information has been rapidly developed, and recently, a thin film transistor having excellent performance of thinning, light weight, and low power consumption has been developed. Thin Film Transistor (TFT) type liquid crystal display (TFT-LCD) has been developed to replace the existing cathode ray tube (CRT).

The image realization principle of the liquid crystal display device uses the optical anisotropy and polarization property of the liquid crystal. As is well known, the liquid crystal has a thin and long molecular structure and optical anisotropy having an orientation in an array, and when placed in an electric field, the liquid crystal has an orientation of molecular arrangement depending on its size. This change is polarized. The liquid crystal display is an essential component of a liquid crystal panel formed by bonding an array substrate and a color filter substrate formed with pixel electrodes and common electrodes facing each other with the liquid crystal layer interposed therebetween. In addition, it is a non-light emitting device which artificially adjusts the arrangement direction of liquid crystal molecules through the electric field change between these electrodes and displays various images by using the light transmittance which is changed at this time.

Recently, the active matrix type, in which pixels, which are the basic units of image expression, are arranged in a matrix manner, and switching elements are arranged in each pixel, is controlled to have excellent attention in terms of resolution and video performance. In addition, thin film transistors (TFTs) are well known as TFT-LCDs (Thin Firm Transistor Liquid Crystal Display devices).

In more detail, as shown in FIG. 1, which is an exploded perspective view of a general liquid crystal display device, the array substrate 10 and the color filter substrate 20 face each other with the liquid crystal layer 30 interposed therebetween. The array substrate 10 includes a plurality of gate wires 14 and data wires 16 arranged vertically and horizontally on the upper surface to define a plurality of pixel regions P, and an intersection of these two wires 14 and 16. A thin film transistor T is provided at the point and is connected one-to-one with the pixel electrode 18 provided in each pixel region P. FIG.

In addition, the upper side of the color filter substrate 20 facing each other borders each pixel region P so as to cover a non-display region of the gate line 14, the data line 16, and the thin film transistor T on the rear surface thereof. The black matrix 25 having a lattice shape is formed, and the red, green, and blue color filter layers 26 are sequentially formed in the lattice to correspond to each pixel area P, and the black matrix is formed. A transparent common electrode 28 is provided over the entire surface of the layer 25 and the red, green, and blue color filter layers 26.

Although not clearly shown in the drawings, these two substrates 10 and 20 are each sealed with a sealing agent or the like along the edges to prevent leakage of the liquid crystal layer 30 interposed therebetween. An upper and lower alignment layer is provided at the boundary between the substrates 10 and 20 and the liquid crystal layer 30 to provide reliability in the molecular alignment direction of the liquid crystal, and at least one outer surface of each of the substrates 10 and 20 has a polarizing plate. Attached.

In addition, a backlight is provided on the back of the liquid crystal panel to supply light. The on / off signal of the thin film transistor T is sequentially scanned and applied to the gate wiring 14. When the image signal of the data wiring 16 is transmitted to the pixel electrode 18 of the pixel region P, the liquid crystal molecules are driven by the vertical electric field therebetween, and various images are changed due to the change in the transmittance of light. I can display it.

On the other hand, in the liquid crystal display device, the insulating substrate serving as the matrix of the array substrate 10 and the color filter substrate 20 has traditionally been used as a glass substrate. Recently, small portable terminals such as laptops and PDAs have been widely used. As it spreads, liquid crystal panels using plastic substrates have been introduced that are lighter, lighter, and more flexible than glass, and thus have a low risk of breakage.

However, a liquid crystal panel using a plastic substrate has a high temperature process requiring a high temperature of 200 ° C. or higher, especially in the manufacture of an array substrate on which a thin film transistor, which is a switching element, is formed. Therefore, heat resistance and chemical resistance are inferior to that of a glass substrate. There is a difficulty in manufacturing the array substrate from a plastic substrate, so that only the color filter substrate constituting the upper substrate is manufactured from the plastic substrate, and the array substrate, the lower substrate, is used to manufacture a liquid crystal display device using a conventional glass substrate.

In order to solve this problem, a technique for manufacturing an array substrate, which is characterized by forming a thin film transistor by performing a low temperature process below 200 ° C. using an organic semiconductor material, has recently been proposed.

Hereinafter, a method of manufacturing an array substrate using an organic semiconductor material which is performed at a low temperature process of 200 ° C. or less will be described.

In forming a pixel including a thin film transistor at a low temperature process of 200 ° C. or less, the characteristics of the thin film transistor may be formed even by forming a metal material, an insulating film, a protective layer, or the like that forms an electrode and wiring through a low temperature deposition or coating method. Although it does not affect much, if the semiconductor layer forming the channel is formed by a low temperature process using amorphous silicon, which is a general semiconductor material, a durable structure may not be dense and important characteristics such as electrical conductivity may be degraded. .

Therefore, in order to overcome this, it is proposed to form an organic semiconductor layer using an organic material having semiconductor characteristics instead of a conventional semiconductor material such as amorphous silicon.

At this time, the organic material having a semiconductor characteristic is largely divided into a high molecular organic semiconductor material and a low molecular organic semiconductor material, the low molecular organic semiconductor material has a superior physical properties such as electrical conductivity compared to the high molecular organic semiconductor material, so the semiconductor material mainly replaces silicon Although it is used as, it is very vulnerable to a solvent such as an organic solvent or alcohol has a disadvantage in that it is difficult to form a solution.

Accordingly, referring to FIG. 2, which is a cross-sectional view of a switching area of an array substrate for a liquid crystal display device having an organic thin film transistor having a bottom contact structure of a conventional bottom gate, a substrate (using a semiconductor material) may be used. When the thin film transistor is formed on the substrate 40, the organic semiconductor material is typically formed on the substrate 40 by evaporation, and the organic semiconductor material may have a structure that is vulnerable to an organic solvent, an alcohol, or the like. In order to minimize the exposure of the material to a solvent such as an organic solvent or an alcohol (which is a component of a developer or an etchant), a gate electrode 43 is usually formed at the lowermost portion, and the surfaces of the source and drain electrodes 50 and 53 are formed. The bottom surface of the organic semiconductor layer 57 is in contact with each other, and is formed in a bottom contact structure of a bottom gate.

However, in the bottom gate structure, the bottom contact has a problem of difficulty in charge injection due to the large contact resistance, and as a result, mobility of the bottom gate is generally low, resulting in deterioration of the characteristics of the thin film transistor. do.

On the other hand, when a top contact structure of a bottom gate is formed using an organic semiconductor material, the thin film transistor has excellent characteristics. However, during patterning, when exposed to a developing solution or an etching solution, its performance as a semiconductor material deteriorates rapidly.

Therefore, as shown in FIG. 3, which is a cross-sectional view showing one pixel area of a conventional array substrate for a liquid crystal display device having a thin film transistor having a top contact structure of a bottom gate, the organic semiconductor material is deposited on a substrate 70. After forming the organic semiconductor layer 78 patterned into a specific shape using a shadow mask or the like, the source and drain electrodes 80 and 82 are also formed on the upper surface of the organic semiconductor layer 78 using a shadow mask 92. Form. However, due to physical limitations using the shadow mask 92, the thin film transistors have a distance d1 between the source and drain electrodes 80 and 82, that is, the length d1 of the channel is more than several tens of micrometers. Since the size of the Tr itself becomes large and affects the aperture ratio, resolution, and the like, it is difficult to apply it to a display device such as an actual liquid crystal display device.

In order to solve the above problems, the present invention provides a thin film transistor having a top gate bottom contact structure without damaging an organic semiconductor layer that is very vulnerable to organic solvents and solvents such as alcohol. It aims at manufacturing the array substrate for liquid crystal display devices provided.

According to an aspect of the present invention, there is provided a method of manufacturing an array substrate for a liquid crystal display device, the method including: forming source and drain electrodes spaced apart from each other on a substrate, and data lines connected to the source electrodes; Forming a pixel electrode in contact with one end of the drain electrode; Continuously forming an organic semiconductor material layer, a gate insulating material layer, a first metal layer, and a second metal layer over the data line, the source and drain electrodes, and the pixel electrode including the spaced apart regions of the source and drain electrodes; Patterning the second metal layer to form a first metal pattern; Dry etching the first metal pattern with an etch mask to form a second metal pattern, a gate insulating film, and an organic semiconductor layer under the same shape as the first metal pattern; Forming a protective layer having a gate contact hole exposing a portion of the first metal pattern over the first metal pattern; Forming a gate wiring on the protective layer through the gate contact hole and in contact with the first metal pattern and crossing the data wiring.

In this case, the forming of the first metal pattern may include forming a photosensitive material layer by coating a photosensitive material on the second metal layer; Exposing the photosensitive material layer using an exposure mask and subsequently developing to form a photosensitive pattern; Etching and removing the second metal layer exposed to the outside of the photosensitive pattern; And removing the photosensitive pattern, wherein the exposed second metal layer is patterned by performing wet etching using an etchant.

In addition, the photosensitive pattern may be removed by stripping or ashing. The first metal layer may be formed of molybdenum (Mo) or chromium (Cr), and the second metal layer may be made of aluminum (Al). ), An aluminum alloy (AlNd), copper (Cu), a copper alloy, and silver (Ag).

The method may further include forming a buffer layer with an insulating material having hydrophilic property on the substrate before forming the data line with the source and drain electrodes, and forming a second passivation layer over the gate line. It includes more.

In addition, the organic semiconductor material layer may be a liquid pentacin (polyacephene) or polythiophene (polythiophene) inkjet device, nozzle coating device, bar coating device, slit coating device, spin (spin) It is characterized by forming by applying using a coating device or a printing device.

The forming of the passivation layer having the gate contact hole may include forming an opening exposing the pixel electrode, wherein the passivation layer may be formed of PVA (poly vinyl alcohol) or photoacryl (photosensitive organic material). photo acryl), and only the exposure and development processes are performed to form the gate contact hole and the opening.

In addition, the dry etching is preferably a dry etching having anisotropic properties.

An array substrate for a liquid crystal display device according to the present invention includes: source and drain electrodes spaced apart from each other on the substrate, and data lines connected to the source electrodes and extending in one direction; An organic semiconductor layer formed over the data line including the source and drain electrodes and a spaced area between the two electrodes; A gate insulating film formed over the organic semiconductor layer in the same form as the organic semiconductor layer; A gate electrode having a double layer structure having the same shape on the gate insulating layer and formed of first and second metal patterns formed of different metal materials; A protective layer having a gate contact hole exposing a portion thereof over the gate electrode of the double layer structure; And a gate line formed to contact the gate electrode of the double layer structure through the gate contact hole over the passivation layer and to cross the data line.

In this case, the organic semiconductor layer is made of pentacin (pentacene) or polythiophene (polythiophene), the gate insulating film is characterized in that made of PVA (poly vinyl alcohol) or fluoropolymer (fluoru polymer).

In addition, the first metal pattern which is a lower layer constituting the double-layered gate electrode is made of molybdenum (Mo) or chromium (Cr), and the second metal pattern as the upper layer is aluminum (Al), aluminum alloy (AlNd), It is characterized by consisting of one material selected from copper (Cu), copper alloy, silver (Ag).

In addition, a buffer layer having a hydrophilic property is further formed below the source and drain electrodes, the data line, and the organic semiconductor layer, and a second protective layer is further formed on the gate line.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

An embodiment of the present invention is to provide a method of manufacturing an array substrate for a liquid crystal display device having a thin film transistor having a top gate structure of a top contact structure and which can be formed without damaging the organic semiconductor layer.

&Lt; Embodiment 1 >

4A to 4E are diagrams illustrating a switching element of an array substrate for a liquid crystal display device having an organic semiconductor pattern formed by coating and patterned without damage by an etchant or the like according to the first embodiment of the present invention. A cross-sectional view of the manufacturing steps for the pixel region. In this case, the region in which the thin film transistor is formed is defined as a switching region.

First, as shown in FIG. 4A, a substrate 101 made of a material having transparent insulating properties, for example, a material having a hydrophilic property on the front surface of a glass or plastic substrate and having excellent adhesion to the substrate 101, for example, oxidation A buffer layer (not shown) is formed by depositing silicon (SiO ₂ ) on the entire surface. This is to improve contact characteristics between the semiconductor layer (not shown) formed on the upper side and the substrate 101 and to form the semiconductor layer (not shown) in an even thickness. In this case, the buffer layer 105 does not necessarily need to be formed, and may be omitted according to the characteristics of the substrate 101.

Next, a low-resistance metal material selected from gold (Au), copper (Cu), copper alloy, aluminum (Al), and aluminum alloy (AlNd) on the buffer layer (not shown) or the substrate 101. The first metal layer is formed by depositing.

Next, a photoresist layer (not shown) is formed on the first metal layer to form a photoresist layer, and the photoresist pattern (not shown) is subjected to an exposure and development process using an exposure mask. After forming the semiconductor substrate, a data line (not shown) extending in one direction by etching the first metal layer exposed to the outside of the photoresist pattern (not shown), and a pixel region P (the gate line and the data formed later) A source electrode 110 connected to the data line (not shown) in the switching region TrA in a region defined by crossing lines, and a drain electrode facing each other at a predetermined interval from the source electrode 110. And form 113.

Next, as shown in FIG. 4B, a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO) is formed on the substrate 101 on which the source and drain electrodes 110 and 113 are formed. Is deposited on the entire surface and patterned by a mask process to form a pixel electrode 115 in direct contact with one end of the drain electrode 113 in the pixel region P. Referring to FIG.

Next, as shown in FIG. 4C, a liquid organic semiconductor material, that is, mobility, is disposed on the data line (not shown), the source and drain electrodes 110 and 113, and the pixel electrode 115. Relatively good low molecular organic semiconductor materials such as liquid pentacene or polythiophene can be used in inkjet devices, nozzle coating devices, bar coating devices, slit coating devices and spin The organic semiconductor material layer 116 is formed by coating the entire surface using a spin coating device or a printing device.

  Next, the gate insulating material layer 123 is formed on the entire surface by applying an organic insulating material, for example, polyvinyl alcohol (PVA) or a fluoropolymer, continuously on the organic semiconductor material layer 116.

Next, a second metal layer 129 is formed by depositing a metal material such as molybdenum (Mo) or chromium (Cr) on the entire surface of the gate insulating material layer 123.

Next, a photoacryl having photosensitive properties is coated on the second metal layer 129 to form a photoacryl layer, and the photoacryl pattern 137 is formed by exposing and developing the photoacryl layer.

 Next, as shown in FIG. 4D, the second metal layer exposed to the outside of the photoacrylic pattern 137 by dry etching using the photoacrylic pattern 137 as an etch mask (129 in FIG. 4C). ) And the gate insulating material layer 123 (FIG. 4C) and the organic semiconductor material layer 116 (FIG. 4C) below.

Therefore, the data line (not shown) and the pixel electrode 115 are exposed in the regions other than the switching region TrA in which the photoacrylic pattern 137 is formed by the dry etching, and at the same time, the switching region An organic semiconductor layer 117 contacting the source and drain electrodes 110 and 113 facing each other and spaced apart from each other and a gate insulating layer 125 and a gate electrode 130 are formed on the TrA. The gate line (not shown) connected to the data line and crossing the data line (not shown) to define the pixel area P is formed.

Next, as shown in FIG. 4E, the ashing process is performed to remove the photoacrylic pattern 137 of FIG. 4D, thereby removing the array substrate 101 for a liquid crystal display device according to the first embodiment of the present invention. I can complete it. In this case, a second passivation layer may be further formed on the gate electrode 130 and the gate wiring (not shown).

&Lt; Embodiment 2 >

However, in the liquid crystal display device array substrate according to the first embodiment described above, when the gate pattern is formed to minimize the damage of the organic semiconductor layer, the gate insulating film and the organic semiconductor layer formed on the entire surface under the first metal layer are etched collectively. Since the organic semiconductor layer is formed under the gate wiring, a small amount of current flows between the pixels through the organic semiconductor layer, which may cause deterioration of the characteristics of the thin film transistor.

The second embodiment of the present invention proposes a method of manufacturing an array substrate for a liquid crystal display device including an organic semiconductor layer, which further improves this one embodiment.

5A through 5F illustrate a switching element of an array substrate for a liquid crystal display device having an organic semiconductor layer formed by coating and patterned without damage by an etchant or the like according to a second embodiment of the present invention. A cross-sectional view of the manufacturing steps of the pixel region P is performed. In this case, the region P in which the thin film transistor Tr, which is the switching element, is formed is defined as a switching region TrA.

First, as shown in FIG. 5A, a material having a transparent insulating property, for example, a material having a hydrophilic property on the front surface of the substrate 201 made of a material of glass or plastic and having excellent adhesion to the substrate 101 A buffer layer (not shown) is formed by depositing silicon oxide (SiO ₂ ) on the entire surface. In this case, the buffer layer (not shown) does not necessarily need to be formed, and may be omitted according to the characteristics of the substrate 101.

Subsequently, a low resistance metal material, for example, gold (Au), copper (Cu), copper alloy, aluminum (Al) or aluminum alloy (AlNd), may be selected on the buffer layer or the substrate 201. Forming a first metal layer (not shown) and patterning the data line to extend in one direction, and the source electrode 210 connected to the data line (not shown) in the switching region TrA. And a drain electrode 213 facing each other at a predetermined interval from the source electrode 210.

Next, a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO) is deposited on the substrate 201 on which the source and drain electrodes 210 and 213 are formed, and then masked. The pixel electrode 215 is in direct contact with one end of the drain electrode 213 in the pixel region P defined by the intersection of the gate line and the data line (not shown), which are subsequently formed by patterning the process. ).

Next, as shown in FIG. 5B, a liquid organic semiconductor material, that is, mobility and the like, is formed on the data line (not shown), the source and drain electrodes 210 and 213, and the pixel electrode 215. Relatively good liquid low molecular organic semiconductor materials such as liquid pentacene or polythiophene, such as inkjet devices, nozzle coating devices, bar coating devices, slit coating devices, The organic semiconductor material layer 216 is formed by coating the entire surface using a spin coating apparatus or a printing apparatus, and subsequently, an organic insulating material, for example, polyvinyl alcohol (PVA) or fluoropolymer (PVA). The gate insulating material layer 223 is formed on the entire surface by applying a fluoru polymer.

Next, a second metal layer 229 is formed by depositing a metal material, for example, molybdenum (Mo) or chromium (Cr), on the front surface of the gate insulating material layer 223, and subsequently the second metal layer 229. Metallic material which can be etched using an etchant having little influence on the metal material constituting the metal layer 229 such as aluminum (Al), aluminum alloy (AlNd), copper (Cu), copper alloy, silver (Ag) The third metal layer 231 is formed by depositing one metal material selected from the layers.

Next, as shown in FIG. 5C, a photosensitive material such as photoresist or photo acryl is applied to the third metal layer 231 of FIG. 5B to form a photosensitive material layer (not shown). The photosensitive pattern 237 is formed to correspond to the switching region TrA by performing an exposure and development process using an exposure mask on the photosensitive material layer (not shown). In this case, the top layer on the substrate 201 is exposed to the developer by the developing process, but the organic semiconductor material layer 216 may include the gate insulating material layer 223 and the second and third metal layers 229 and 231 of FIG. 5B. It is not a problem because it is hidden in double triple by).

Next, a third metal pattern 232 is formed by etching and removing the third metal layer 231 of FIG. 5B exposed to the outside of the photosensitive pattern 237, and at the same time, the second metal layer 237 is exposed to the outside of the photosensitive pattern 237. The metal layer 229 is exposed.

In this case, the etching for forming the third metal pattern 232 may be performed by a wet time using an etchant reacting with the third metal layer 231 of FIG. 5B.

Next, as shown in FIG. 5D, the photosensitive pattern (237 of FIG. 5C) is removed by performing a strip process. In this case, the substrate 201 is exposed to the strip liquid during the strip process, but the organic semiconductor material layer 216 is still the gate insulating material layer 223 and the second metal layer 229. It is obscured by, so it doesn't matter at all.

In this case, since the photosensitive pattern 237 of FIG. 5C has not been subjected to dry etching or the like, it may be removed by ashing. When the photosensitive pattern exposed to the dry etching is subjected to ashing, a residue remains, and when contacting with a metal material, the contact resistance is increased to deteriorate characteristics.

However, in the second embodiment of the present invention, the photosensitive pattern is removed by any ashing or stripping process.

Next, as shown in FIG. 5E, the second metal layer exposed to the outside of the third metal pattern 232 by performing anisotropic dry etching using the third metal pattern 232 as an etching mask (229 in FIG. 5D). ) And the gate insulating material layer 223 of FIG. 5D and the organic semiconductor material layer 216 of FIG. 5D are sequentially removed.

Accordingly, the second metal pattern 230, the gate insulating layer 225, and the organic semiconductor layer 217 having the same shape are sequentially formed below the third metal pattern 232. In this case, the second metal pattern 230 and the third metal pattern 232 thereon form a gate electrode 233 having a double layer structure. In addition, the gate wiring is not formed at this stage due to the characteristics of the second embodiment of the present invention.

Next, as shown in FIG. 5F, a photosensitive organic insulating material, for example, polyvinyl alcohol (PVA) or photo acryl, is coated on the entire surface of the double-layered gate electrode 233 to form a protective layer 240. And an opening for exposing the gate contact hole 245 exposing a part of the gate electrode 233 of the double layer structure and the pixel electrode 215 in the pixel region P by directly exposing, developing and patterning the same. op).

In this case, since the organic semiconductor layer 217 is completely covered by the protective layer 240, the organic semiconductor layer 217 by the developer used during the patterning of the protective layer is not affected at all. It will not be damaged.

Next, as illustrated in FIG. 5G, a metal material having low resistance characteristics, such as aluminum (Al) and aluminum alloy (AlNd), may be formed on the protective layer 240 having the gate contact hole 245 and the opening op. Contacting the gate electrode 233 of the double layer structure through the gate contact hole 245 by depositing and patterning a material selected from among copper (Cu), copper alloy, and silver (Ag). The gate wiring 250 defining the pixel region P is formed to intersect with each other. Although not shown in the drawings, a second passivation layer may be further formed on the gate line 250.

The array substrate for a liquid crystal display device according to the second exemplary embodiment manufactured by the manufacturing method includes a gate electrode 233 and a gate wiring 245 formed by collectively etching to form the organic semiconductor layer 217 without damaging the organic semiconductor layer 217. By this dualization, since a semiconductor pattern made of an organic semiconductor is not formed under the gate wiring 245, the deterioration of characteristics due to energization between neighboring pixels does not occur.

In addition, by forming the gate electrode 233 as a double layer structure, it is possible to remove the photosensitive pattern remaining on the uppermost third metal pattern 232 without damaging the lower organic semiconductor layer. It is an enemy.

The present invention provides an array for a liquid crystal display device having an organic thin film transistor having a top gate bottom contact structure that forms an organic semiconductor layer without damage by using an organic semiconductor material having low chemical resistance and further improves characteristics. There is an effect of providing a method of manufacturing a substrate.

In addition, the gate electrode and the gate wiring are dualized to be formed on different layers and electrically connected to each other, thereby preventing deterioration of characteristics due to energization between neighboring pixels through the organic semiconductor layer.

In addition, in the formation of the gate electrode and the organic semiconductor layer to be collectively etched in nature, there is provided a manufacturing method that does not damage the organic semiconductor layer even if the photosensitive pattern on the gate electrode is stripped and removed so that no residue remains. This has the effect of improving characteristics such as lowering the contact resistance.

In addition, by forming an organic semiconductor layer using a liquid semiconductor organic material without using expensive vacuum equipment, there is an effect of reducing the initial equipment cost to improve the price competitiveness of the product.

Claims (17)

Forming source and drain electrodes spaced apart from each other on a substrate, and data lines connected to the source electrodes; Forming a pixel electrode in contact with one end of the drain electrode; Continuously forming an organic semiconductor material layer, a gate insulating material layer, a first metal layer, and a second metal layer over the data line, the source and drain electrodes, and the pixel electrode including the spaced apart regions of the source and drain electrodes; Patterning the second metal layer to form a first metal pattern; Dry etching the first metal pattern with an etch mask to form a second metal pattern, a gate insulating film, and an organic semiconductor layer under the same shape as the first metal pattern; Forming a protective layer having a gate contact hole exposing a portion of the first metal pattern over the first metal pattern; Forming a gate wiring contacting the first metal pattern and crossing the data wiring through the gate contact hole on the passivation layer; And a plurality of pixel electrodes formed on the substrate. The method of claim 1, Forming the first metal pattern, Applying a photosensitive material onto the second metal layer to form a photosensitive material layer; Exposing the photosensitive material layer using an exposure mask and subsequently developing to form a photosensitive pattern; Etching and removing the second metal layer exposed to the outside of the photosensitive pattern; Removing the photosensitive pattern And a plurality of pixel electrodes formed on the substrate. The method of claim 2, The exposed second metal layer may be patterned by performing wet etching using an etchant. The method of claim 2, The removal of the photosensitive pattern is a manufacturing method of an array substrate for a liquid crystal display device characterized in that it is made through a strip (strip) or ashing (ashing). The method of claim 2, The first metal layer is made of molybdenum (Mo) or chromium (Cr), And wherein the second metal layer is one selected from aluminum (Al), aluminum alloy (AlNd), copper (Cu), copper alloy, and silver (Ag). The method of claim 1, Before forming data lines with the source and drain electrodes, And forming a buffer layer of an insulating material having hydrophilic properties on the substrate. The method of claim 1,   And forming a second passivation layer over the gate line. The method of claim 1, The organic semiconductor material layer is a liquid pentacin (polyacephene) or polythiophene (polythiophene) inkjet device, nozzle coating device, bar coating device, slit coating device, spin coating A method of manufacturing an array substrate for a liquid crystal display device, characterized in that it is formed by coating with a device or printing device. The method of claim 1, Forming a protective layer having the gate contact hole, And forming an opening for exposing the pixel electrode. The method of claim 9, The protective layer is formed of PVA (poly vinyl alcohol) or photo acryl (photoacryl), a photosensitive organic material, and performs only an exposure and development process to form the gate contact hole and the opening. Method of preparation. The method of claim 1, And said dry etching is a dry etching having anisotropic properties. Source and drain electrodes spaced apart from each other on the substrate, and data lines connected to the source electrodes and extending in one direction; An organic semiconductor layer formed over the data line including the source and drain electrodes and a spaced area between the two electrodes; A gate insulating film formed over the organic semiconductor layer in the same form as the organic semiconductor layer; A gate electrode having a double layer structure having the same shape on the gate insulating layer and formed of first and second metal patterns formed of different metal materials; A protective layer having a gate contact hole exposing a portion thereof over the gate electrode of the double layer structure; A gate wiring formed on the protective layer through the gate contact hole and in contact with the gate electrode having the double layer structure and crossing the data wiring; Array substrate for a liquid crystal display device comprising a. 13. The method of claim 12, The organic semiconductor layer is a pentacin (pentacene) or polythiophene (polythiophene) characterized in that the array substrate for a liquid crystal display device. 13. The method of claim 12, And the gate insulating layer is made of polyvinyl alcohol (PVA) or fluoropolymer. 13. The method of claim 12, The first metal pattern, which is a lower layer forming the double layer gate electrode, is formed of molybdenum (Mo) or chromium (Cr), The second metal pattern as the upper layer is made of one of aluminum (Al), aluminum alloy (AlNd), copper (Cu), copper alloy, silver (Ag) array substrate for a liquid crystal display device. 13. The method of claim 12, And a buffer layer having a hydrophilic property under the source and drain electrodes, the data line, and the organic semiconductor layer. 13. The method of claim 12, And a second passivation layer further formed on the gate line.

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