KR101950822B1 - Thin film transistor substrate and method of fabricating the same - Google Patents

Abstract

The present invention relates to a thin film transistor substrate including a pixel electrode capable of eliminating a color filter layer and achieving color while having conductivity, and a method of manufacturing the thin film transistor substrate.
A gate electrode formed on the substrate including the pixel portion; A gate insulating film formed on the entire surface of the substrate so as to cover the gate electrode; An active layer formed on the gate insulating film so as to at least partially overlap with the gate electrode; A source electrode and a drain electrode formed on both sides of the active layer, the source electrode and the drain electrode being spaced apart from each other on the gate insulating film; A pixel electrode connected to the drain electrode; A protective film formed on the front surface of the substrate so as to cover the source and drain electrodes and the pixel electrode; And a common electrode between the pixel electrode and the fringe field with the protective film interposed therebetween, wherein the pixel electrode is formed by doping the conductive nanowire with a coloring material.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a thin film transistor substrate,

The present invention relates to a thin film transistor substrate and a method of manufacturing the thin film transistor substrate, and more particularly, to a thin film transistor substrate including a pixel electrode capable of eliminating a color filter layer and achieving color while having conductivity, and a method of manufacturing the same.

A display device for displaying an image includes a cathode ray tube, a liquid crystal display (LCD), a plasma display panel (PDP), an electroluminescence display device (ELD) And an electroluminescence field display device.

2. Description of the Related Art Liquid crystal displays (LCDs) typically display an image by allowing each of liquid crystal cells arranged in a matrix form to control light transmittance according to a video signal.

The liquid crystal display panel includes a thin film transistor substrate and a color filter substrate which are bonded together by a cohesive agent with a liquid crystal therebetween. Electrodes are arranged on two substrates, liquid crystal directors are arranged so as to twist by 90 °, A twisted-nematic (TN) method for driving a liquid crystal director, forming two electrodes on one substrate, and forming an IPS (liquid crystal alignment) In-Plane Switching mode, a Fringe Field Swiching (FFS) mode method in which two electrodes are formed as transparent conductors while the interval between the two electrodes is narrowed to operate the liquid crystal molecules by the fringe field formed between the two electrodes .

The thin film transistor substrate of the fringe field type includes a thin film transistor including a source electrode and a drain electrode on a lower substrate, a pixel electrode connected to a drain electrode of the thin film transistor, a source electrode and a drain electrode on the lower substrate, A protective film formed to cover the electrode, and a common electrode formed on the protective film and forming a fringe electric field with the pixel electrode.

And a color filter substrate bonded together with the thin film transistor substrate and the liquid crystal layer interposed therebetween is formed to include a color filter layer on the upper substrate. Here, the color filter layer may be formed on the thin film transistor substrate.

Meanwhile, in recent years, in order to reduce the manufacturing cost and the manufacturing process, a method of eliminating the color filter layer in a conventional liquid crystal display device has been sought.

It is an object of the present invention to provide a thin film transistor substrate including a pixel electrode capable of eliminating a color filter layer and achieving color while having conductivity, and a manufacturing method thereof.

According to an aspect of the present invention, there is provided a thin film transistor substrate including: a gate electrode formed on a substrate including a pixel portion; A gate insulating film formed on the entire surface of the substrate so as to cover the gate electrode; An active layer formed on the gate insulating film so as to at least partially overlap with the gate electrode; A source electrode and a drain electrode formed on both sides of the active layer, the source electrode and the drain electrode being spaced apart from each other on the gate insulating film; A pixel electrode connected to the drain electrode; A protective film formed on the front surface of the substrate so as to cover the source and drain electrodes and the pixel electrode; And a common electrode between the pixel electrode and the fringe field with the protective film interposed therebetween, wherein the pixel electrode is formed by doping the conductive nanowire with a coloring material.

The coloring material may be any one of a red dye, a green dye and a blue dye.

Wherein the red dye is an oxide containing a Ru ^{2 +} system Rare earth ion or a Fe ^{2 +} system transition metal ion, the green dye is an oxide containing a Cr ^{3 +} system transition metal ion, and the blue dye is a Co ^{2 +} And may be an oxide containing a transition metal ion.

The coloring material may be a metal nanoparticle that generates red color, green color, and blue color depending on its size.

The metal nanoparticles may include gold nanoparticles.

According to an aspect of the present invention, a thin film transistor substrate may further include an overcoat layer formed on the pixel electrode.

The coloring material may be doped to the conductive nanowire by a binder.

According to another aspect of the present invention, there is provided a method of manufacturing a thin film transistor substrate, including: forming a gate electrode on a substrate including a pixel portion; Forming a gate insulating film on the entire surface of the substrate so as to cover the gate electrode; Forming an active layer on the gate insulating film so as to overlap at least a part with the gate electrode; Forming a source electrode and a drain electrode on both sides of the active layer, the source electrode and the drain electrode being spaced apart from each other on the gate insulating film; Forming a pixel electrode connected to the drain electrode; Forming a protective film on the entire surface of the substrate so as to cover the source electrode and the drain electrode and the pixel electrode; And forming a common electrode between the pixel electrode and the fringe field with the protective film interposed therebetween, wherein the pixel electrode is formed by coating a solution formed by doping the conductive nanowire with a coloring material on the gate insulating layer of the pixel portion Is formed.

According to another aspect of the present invention, there is provided a method of manufacturing a thin film transistor substrate, the method including forming an overcoat layer on the pixel electrode.

The coloring material may be doped to the conductive nanowire by a binder.

Wherein the pixel portion is included in one of a red sub-pixel, a green sub-pixel, and a blue sub-pixel, and the pattern of the red sub-pixel, the pattern of the green sub- The pixel electrode may be formed for each pixel pattern.

The pixel portion may be included in one of a red sub-pixel, a green sub-pixel, and a blue sub-pixel. In the forming of the pixel electrode, a pattern of the red sub- The pixel electrode may be formed for each pattern of blue sub-pixels.

The thin film transistor substrate according to the embodiment of the present invention includes a pixel electrode formed by doping a conductive nanowire with a coloring material so that the electrode role of the pixel electrode and the role of color of the color filter layer are realized in one layer . Therefore, the thin film transistor substrate according to the embodiment of the present invention can reduce the manufacturing cost and manufacturing process by eliminating the separate color filter layer.

In addition, the thin film transistor substrate according to an embodiment of the present invention is disposed at a lower portion of a substrate and is positioned close to a backlight unit that provides light toward the substrate, thereby increasing the contrast ratio and color purity retention rate through the pixel electrode have.

In addition, the thin film transistor substrate according to the embodiment of the present invention can replace the expensive ITO used to form the pixel electrode by forming the pixel electrode using the conductive nanowire.

1 is a cross-sectional view illustrating a thin film transistor substrate according to an embodiment of the present invention.
FIG. 2A is a view illustrating the structure of the pixel electrode shown in FIG.
FIG. 2B is a view showing the structure of the pixel electrode shown in FIG.
FIG. 3 is a view showing an example of a coloring material and a binder when the pixel electrode shown in FIG. 1 realizes blue color.
FIG. 4 is a view showing a portion corresponding to the structure of the pixel electrode of FIG. 2A among the thin film transistor substrates according to another embodiment of the present invention.
5 is a cross-sectional view illustrating a thin film transistor substrate according to another embodiment of the present invention.
6A to 6E are cross-sectional views illustrating a method of manufacturing a TFT substrate according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 is a cross-sectional view illustrating a thin film transistor substrate according to an embodiment of the present invention.

1, a fringe field formed between the pixel electrode 118 and the common electrode 108 passes liquid crystal molecules (not shown) positioned on the pixel portion PA and the pixel electrode 118 through the slit 108S A thin film transistor substrate of a fringe field type liquid crystal display device which implements an image by driving the thin film transistor substrate is shown as an example.

1 shows one sub-pixel including a data pad unit DPA, a gate pad unit GPA and a pixel unit PA for convenience of explanation. In a practical liquid crystal display device, for example, A plurality of pixels including a red sub-pixel, a green sub-pixel, and a blue sub-pixel are arranged.

1, a thin film transistor substrate 100 according to an embodiment of the present invention includes thin film transistors connected to gate lines (not shown) and data lines 117 on a substrate 110, A protective film 115b formed on the pixel electrode 118 and a common electrode 108 forming a pixel electrode 118 and a fringe field.

The thin film transistor causes a pixel signal supplied to the data line 117 to be charged and held in the pixel electrode 118 in response to a scan signal supplied to the gate line. The thin film transistor includes a gate electrode 121, a gate insulating film 115a, a source electrode 122, a drain electrode 123, an active layer 124, and an ohmic contact layer 125n.

The gate electrode 121 is connected to the gate line to supply a scan signal from the gate line. The gate insulating layer 115a is formed on the entire surface of the substrate 110 so as to cover the gate electrode 121. [ The source electrode 122 and the drain electrode 123 are formed on both sides of the active layer 124 so as to be spaced apart from each other on the gate insulating film 115a. The source electrode 122 is connected to the data line 117 so that a pixel signal from the data line 117 is supplied. The drain electrode 123 is formed so as to face the source electrode 122 with the channel portion of the active layer 124 interposed therebetween to supply a pixel signal from the data line 117 to the pixel electrode 118. The active layer 124 overlaps the gate electrode 121 with the gate insulating layer 115a interposed therebetween to form a channel portion between the source electrode 122 and the drain electrode 123. The ohmic contact layer 125n is formed on the active layer 124 between the source electrode 122 and the drain electrode 123 and between the active layer 124 and the channel layer. The ohmic contact layer 125n serves to reduce electrical contact resistance between the source electrode 122 and the drain electrode 123 and the active layer 124, respectively.

The pixel electrode 118 is formed to be connected to the drain electrode 123 on the gate insulating film 115a of the pixel portion PA. The pixel electrode 118 may be a plate type and receives a pixel signal from the data line 117 through the drain electrode 123 of the TFT. The pixel electrode 118 is formed so as to have conductivity and simultaneously realize a color, and a separate color filter layer formed on a thin film transistor substrate or a separate color filter layer formed on a color filter substrate, Thereby enabling the deletion of the color filter layer. The pixel electrode 118 is disposed at a lower portion of the substrate 110 and is positioned close to a backlight unit (not shown) for providing light toward the substrate 110 to emit light, And the color purity retention ratio can be increased. Here, the pixel electrode 118 may be formed to emit red when the pixel portion PA is included in the red sub-pixel, and may be configured to emit green when the pixel portion PA is included in the green sub-pixel. , And blue when the pixel portion PA is included in the blue sub-pixel. The pixel electrode 118 will be described in detail below.

The passivation layer 115b is formed on the entire surface of the substrate 110 so as to cover the source electrode 122 and the drain electrode 123 and the pixel electrode 118. [ The passivation layer 115b is formed of an insulating material and serves to insulate the source electrode 122 and the drain electrode 123 from the pixel electrode 118 from other structures.

The common electrode 108 is formed to be connected to a common line (not shown) on the passivation layer 115b of the pixel portion PA and is supplied with a common voltage through a common line. The common electrode 108 may have a plurality of slits 108_S and overlap the pixel electrode 118 with a protective film 115b therebetween to form a fringe field. The liquid crystal molecules arranged in the horizontal direction between the thin film transistor substrate 100 and the color filter substrate are rotated by the dielectric anisotropy by the fringe field. The light transmittance through the pixel portion PA is changed according to the degree of rotation of the liquid crystal molecules, thereby realizing an image. The common electrode 108 is formed of a transparent conductive material and may be formed of a transparent conductive material such as tin oxide (TO), indium tin oxide (ITO), indium zinc oxide (IZO) Indium Tin Zinc Oxide (ITZO) or the like may be used.

A gate pad electrode 126p and a data pad electrode 127p electrically connected to the gate line and the data line 117 are formed at the edge of the thin film transistor substrate 100 constructed as described above, (Not shown) are transmitted to the gate lines and the data lines 117, respectively. That is, the gate line and the data line 117 extend to the driving circuit portion and are connected to the corresponding gate pad line 116p and the data pad line 117p, respectively, and the gate pad line 116p and the data pad line 117p The scan signal and the pixel signal are respectively received from the driving circuit through the gate pad electrode 126p and the data pad electrode 127p which are electrically connected to the gate pad line 116p and the data pad line 117p, respectively. Here, a first amorphous silicon thin film pattern 124 'and a second n + amorphous silicon thin film pattern 125' 'may be formed under the data line 117, and a second amorphous silicon thin film pattern 125' The amorphous silicon thin film pattern 124 '' and the third n + amorphous silicon thin film pattern 125 '' 'may be formed.

Hereinafter, the structure of the pixel electrode of the TFT according to the exemplary embodiment of the present invention will be described in detail.

FIG. 2A illustrates a structure of the pixel electrode shown in FIG. 1, FIG. 2B illustrates a structure of the pixel electrode shown in FIG. 1, and FIG. 3 illustrates a structure in which the pixel electrode shown in FIG. A coloring material and a binder. Fig.

Referring to FIG. 2A, the pixel electrode 118 is formed by doping a conductive nanowire 118a having an OH group with a coloring material 118b. 2B, the pixel electrode 118 is formed by doping a dye, which is a coloring material 118b, into a conductive nanowire 118a having an OH group using a binder 10. [ Here, the conductive nanowire 118a may be formed of silver (Ag) or carbon (C). The dye may be any one selected from a red dye, a green dye, and a blue dye. For example, when the pixel portion (PA of FIG. 1) is included in the red sub-pixel, the coloring material 118b of the pixel electrode 118a may be a red dye and the pixel portion (PA of FIG. 1) The coloring material 118b of the pixel electrode 118a may be green dye and the coloring material 118b of the pixel electrode 118a when the pixel portion (PA of FIG. 1) is included in the blue sub- It may be a blue dye. Here, the red dye may be an oxide including a Ru ^{2 +} -based rare earth ion or a Fe ^{2 +} -based transition metal ion. The green dye may be an oxide containing a Cr ^{3 +} system transition metal ion. The blue dye may be an oxide comprising Co ^{2 +-based} transition metal ion.

3, when the pixel portion (PA in FIG. 1) is included in the blue sub-pixel, the coloring material 118b of the pixel electrode 118a is, for example, 3-aminopropyltrimethoxysilane (APTMS) For example, Fluorescein 5 (6) isothiocyanate (FITC) or Rhodamine B isothiocyanate (RBITC).

As described above, the thin film transistor substrate 100 according to an embodiment of the present invention includes the pixel electrode 118 formed by doping the conductive nanowire 118a having an OH group with a coloring material 118b, which is a dye, The role of the electrode of the pixel electrode and the color implementation of the color filter layer can be performed in one layer. Therefore, the thin film transistor substrate 100 according to the embodiment of the present invention can reduce the manufacturing cost and manufacturing process by eliminating the separate color filter layer.

In addition, the thin film transistor substrate 100 according to an embodiment of the present invention is disposed at a lower portion of the substrate 110 and is positioned close to a backlight unit for providing light toward the substrate 110, The contrast ratio and color purity retention ratio of the liquid crystal display device can be increased through the liquid crystal layer 118.

In addition, the thin film transistor substrate 100 according to an exemplary embodiment of the present invention can be formed by using the conductive nanowire to replace the pixel electrode 118 with the expensive ITO used to form the pixel electrode have.

Next, a thin film transistor substrate according to another embodiment of the present invention will be described.

FIG. 4 is a view showing a portion corresponding to the structure of the pixel electrode of FIG. 2A among the thin film transistor substrates according to another embodiment of the present invention.

The thin film transistor substrate according to another embodiment of the present invention has the same structure and the same function as the thin film transistor substrate 100 of FIG. 1 except that the structure of the pixel electrode 218 is different. Accordingly, in the thin film transistor substrate according to another embodiment of the present invention, only the structure of the pixel electrode 218 will be described with reference to FIG.

Referring to FIG. 4, the pixel electrode 218 of the thin film transistor substrate according to another embodiment of the present invention is similar to the pixel electrode 118 of FIG.

However, the pixel electrode 218 is formed by doping the conductive nanowire 118a with a coloring material 218b which is metal nanoparticles. Here, the metal nanoparticles are particles capable of generating different colors depending on sizes, for example, red color, green color, and blue color. The metal nanoparticles may be gold nanoparticles, for example, the gold nanoparticle itself may generate a red color, the gold nanoparticle material treated with silver sulfide may generate a green color, Treated silver-based gold nanoparticle materials can produce blue color.

The pixel electrode 218 configured as above generates a color using a scattering effect. Although not shown, the coloring material 218b, which is a metal nanoparticle, can also be doped to the conductive nanowire 118a having an OH group by a binder.

As described above, according to another embodiment of the present invention, a thin film transistor substrate includes a conductive nanowire 118a having an OH group and a pixel electrode (not shown) formed by doping a coloring material 218b, which is metal nanoparticles, 218), the role of the electrode of the pixel electrode and the role of color of the color filter layer can be realized in one layer. Therefore, the thin film transistor substrate according to another embodiment of the present invention can reduce the manufacturing cost and manufacturing process by eliminating the separate color filter layer.

The thin film transistor substrate according to another embodiment of the present invention includes a pixel electrode 218 disposed at a lower portion of a substrate 110 and positioned close to a backlight unit for providing light toward the substrate 110, The contrast ratio and color purity retention ratio of the liquid crystal display device can be increased.

In addition, the thin film transistor substrate according to another embodiment of the present invention can replace the expensive ITO used to form the pixel electrode by forming the pixel electrode 218 using the conductive nanowire.

In addition, the thin film transistor substrate according to another embodiment of the present invention is formed by using the coloring material 218b, which is metal nanoparticles, as the pixel electrode 218, thereby improving the electrical characteristics So that it is possible to cope with a high temperature process.

Next, a thin film transistor substrate 300 according to another embodiment of the present invention will be described.

5 is a cross-sectional view illustrating a thin film transistor substrate according to another embodiment of the present invention.

5, the thin film transistor substrate 300 according to another embodiment of the present invention has the same structure as the thin film transistor substrate 300 except that the overcoat layer 319 is formed in comparison with the thin film transistor substrate 100 of FIG. It plays a role. Accordingly, only the overcoat layer 319 will be described in the thin film transistor substrate 300 according to another embodiment of the present invention.

The overcoat layer 319 of the thin film transistor substrate 300 according to another embodiment of the present invention is formed on the pixel electrode 118 and is formed of a transparent conductive material. The overcoat layer 319 reinforces the hardness of the pixel electrode 118 to prevent the pixel electrode 118 from being damaged during the manufacturing process of the TFT substrate 300.

As described above, the thin film transistor substrate 300 according to another embodiment of the present invention includes a pixel electrode 118a formed by doping a coloring material (118b in FIG. 1) to a conductive nanowire (118a in FIG. 1) The pixel electrode 118 and the color filter layer can be formed in a single layer through the overcoat layer 319 formed on the pixel electrode 118. In addition, It is possible to reinforce the hardness of Accordingly, the thin film transistor substrate 300 according to another embodiment of the present invention can reduce the manufacturing cost and the manufacturing process by eliminating the separate color filter layer, and can prevent the damage of the pixel electrode 118.

5, the overcoat layer 319 is formed on the pixel electrode 118 of the thin film transistor substrate 100 according to an embodiment of the present invention. However, in the thin film transistor substrate 100 according to another embodiment of the present invention, The pixel electrode 218 may be formed of a metal.

Hereinafter, a method of manufacturing a thin film transistor substrate will be described with reference to a method of manufacturing a thin film transistor substrate according to an embodiment of the present invention.

6A to 6E are cross-sectional views illustrating a method of manufacturing a TFT substrate according to an embodiment of the present invention.

Referring to FIG. 6A, a gate electrode 121 is formed on a substrate 110 including a pixel portion PA. At this time, a gate pad line (116p) is formed together with the gate pad portion (GPA) of the substrate (110). Although not shown, a gate line connected to the gate electrode 121 is also formed when the gate electrode 121 is formed.

The gate electrode 121, the gate pad line 116p, and the gate line are formed by selectively depositing a first conductive layer on the entire surface of the substrate 110 and then performing a photolithography process. Here, the first conductive layer may be a low resistance opaque conductive material such as aluminum, an aluminum alloy, tungsten (W), copper (Cu), molybdenum (Mo), molybdenum alloy, . The first conductive layer may have a multi-layer structure in which two or more low resistance conductive materials are stacked.

6B, a gate insulating layer 115a is formed on the entire surface of the substrate 110 so as to cover the gate electrode 121. An active layer 115a is formed on the gate insulating layer 115a so as to overlap with the gate electrode 121 at least partially. And a source electrode 122 and a drain electrode 123 are formed on both sides of the active layer 124 on the gate insulating film 115a.

Specifically, when the gate insulating film 115a is formed on the substrate 110, an amorphous silicon thin film, an n + amorphous silicon thin film, and a second conductive film are formed. Thereafter, the amorphous silicon thin film, the n + amorphous silicon thin film and the second conductive film are selectively removed through a photoresist process to form an active layer 124 made of an amorphous silicon thin film on the pixel portion PA of the substrate 110, A source electrode 122 and a drain electrode 123 made of a conductive film are formed. At this time, a first n + amorphous silicon thin film pattern 125 'formed of an n + amorphous silicon thin film and patterned in the same manner as the active layer 124 is formed on the active layer 124. The first amorphous silicon film and the n + amorphous silicon film are patterned in the same manner as the data line 117 and the data pad line 117p, respectively, under the data line 117 and the data pad line 117p. A second n + amorphous silicon thin film pattern 125 '', a second amorphous silicon thin film pattern 124 '' and a third n + amorphous silicon thin film pattern 125 'are respectively formed. Here, the second conductive layer may be a low-resistance opaque conductive material such as aluminum, aluminum alloy, tungsten copper, chromium, molybdenum, and molybdenum alloy.

Next, referring to FIG. 6C, a pixel electrode 118 connected to the drain electrode 123 is formed on the gate insulating film 115a.

Specifically, the pixel electrode 118 is formed by applying a solution prepared by doping a coloring material 118b, which is a dye, to a conductive nanowire 118a having an OH group using a binder 10, And connected to the drain electrode 123 of the portion PA. Here, the pixel portion PA of the substrate 110 is included in one of the red sub-pixel, the green sub-pixel, and the blue sub-pixel. Accordingly, the pixel electrode 118 can be formed by a pattern of a red sub-pixel, a pattern of a green sub-pixel, and a pattern of a blue sub-pixel by a printing method. For example, when a red dye is selected as the coloring material 118b, the solution is printed so as to be connected to the drain electrode 123 of the pixel portion PA of the substrate 110 included in the pattern of the red sub-pixel. When the green dye is selected as the coloring material 118b, the solution is printed so as to be connected to the drain electrode 123 of the pixel portion PA of the substrate 110 included in the pattern of the green sub-pixel. When the blue dye is selected as the coloring material 118b, the solution is printed so as to be connected to the drain electrode 123 of the pixel portion PA of the substrate 110 included in the pattern of the blue sub-pixel.

The pixel electrode 118 is formed by depositing a solution made by doping a conductive nanowire 118a having an OH group with a coloring material 118b as a dye by using a binder 10 on a substrate 110, And the cured material is partially etched by an etching method to be connected to the drain electrode 123 of the pixel portion PA of the substrate 110. [ For example, when a red dye is selected as the coloring material 118b, a solution is deposited on the entire surface of the substrate 110 and cured, and then the cured material is partially etched to form a substrate 110, In the pixel portion PA of FIG. Thereafter, when a green dye is selected as the coloring material 118b, a solution is deposited on the entire surface of the substrate 110 and is cured. Then, the cured material is partially etched to form a pattern of the green sub- And remains in the pixel portion PA. Then, when a blue dye is selected as the coloring material 118b, a solution is deposited on the entire surface of the substrate 110 and cured, and then the cured material is partially etched to form a pattern of the blue sub- And remains in the pixel portion PA.

Although not illustrated, the pixel electrode 218 of FIG. 4 may also be formed in the same manner as the pixel electrode 118. The overcoat layer 319 of FIG. 5 may be formed through a deposition method after formation of the pixel electrode 118.

6D, a protective film 115b is formed on the entire surface of the substrate 110 so as to cover the reference screen, the source electrode 122, the drain electrode 123, and the pixel electrode 118. Next, The protective film 115b is selectively removed through a photolithography process so that a data pad line 117p and a gate pad line 116p are formed on the data pad portion DPA and the gate pad portion GPA of the substrate 110, A first contact hole 140a and a second contact hole 140b are formed to expose a part of the first contact hole 140a.

Next, referring to FIG. 6E, a common electrode 108 constituting a fringe field is formed between the pixel electrode 118 and the protective film 115b.

Specifically, a third conductive layer made of a transparent conductive material is formed on the entire surface of the passivation layer 115b on which the first contact hole 140a and the second contact hole 140b are formed. Then, the third conductive layer is selectively patterned using a photolithography process, A common electrode 108 having a plurality of slits 108S in the portion PA is formed. Here, the third conductive layer may be a transparent conductive material having excellent transmittance such as indium-tin-oxide or indium-zinc-oxide.

As described above, the method of manufacturing a thin film transistor substrate according to an embodiment of the present invention can simplify a manufacturing process by forming a pixel electrode simultaneously acting as an electrode and a color in a nanowire as a solution doped with a coloring material .

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation and that those skilled in the art will understand that various modifications and equivalent arrangements may be made therein It will be possible.

100, 300: thin film transistor substrate 108: common electrode
110: substrate 115a: gate insulating film
115b: protective film 118, 218: pixel electrode
118a: conductive nanowire 118b: coloring material
122: source electrode 123: drain electrode
124: active layer 125n: ohmic contact layer
319: Overcoat layer

Claims (15)

A gate electrode formed in each sub-pixel on a substrate including a pixel portion including a plurality of sub-pixels;
A gate insulating film formed on the entire surface of the substrate so as to cover the gate electrode;
An active layer formed on the gate insulating film so as to at least partially overlap with the gate electrode;
A source electrode and a drain electrode formed on both sides of the active layer, the source electrode and the drain electrode being spaced apart from each other on the gate insulating film;
A pixel electrode directly connected to a part of a top surface and a side surface of the drain electrode, the pixel electrode being in contact with the gate insulating film except a connection portion with the drain electrode and doped with a coloring material at a terminal polarity of the conductive nanowire;
A protective film formed on the front surface of the substrate so as to cover the source and drain electrodes and the pixel electrode; And
And a common electrode forming the fringe field with the pixel electrode sandwiched by the protective film. The method according to claim 1,
Wherein the coloring material is any one of a red dye, a green dye, and a blue dye. 3. The method of claim 2,
The red dye is an oxide containing a Ru ^{2 +} system rare earth ion or Fe ^{2 +} system transition metal ion,
The green dye is an oxide containing a Cr ^{3 +} system transition metal ion,
It said blue dye is a thin film transistor substrate, wherein an oxide containing Co ^{2 +-based} transition metal ion. The method according to claim 1,
Wherein the coloring material is a metal nanoparticle that generates red, green, and blue colors having different wavelengths depending on sizes. 5. The method of claim 4,
Wherein the metal nanoparticles include gold nanoparticles. The method according to claim 1,
And an overcoat layer directly adjacent to the pixel electrode. The method according to claim 1,
Wherein the coloring material is doped to the conductive nanowire by a binder. Forming a gate electrode in each sub-pixel on a substrate including a pixel portion having a plurality of sub-pixels;
Forming a gate insulating film on the entire surface of the substrate so as to cover the gate electrode;
Forming an active layer on the gate insulating film so as to overlap at least a part with the gate electrode;
Forming a source electrode and a drain electrode on both sides of the active layer, the source electrode and the drain electrode being spaced apart from each other on the gate insulating film;
Forming a pixel electrode directly connected to a part of a top surface of the drain electrode and a side surface of the conductive nanowire, the pixel electrode being in contact with the gate insulating film except a connection portion with the drain electrode and doped with a coloring material in a terminal polar group of the conductive nanowire;
Forming a protective film on the entire surface of the substrate so as to cover the source electrode and the drain electrode and the pixel electrode; And
And forming a common electrode between the pixel electrode and the fringe field through the protective film. 9. The method of claim 8,
And forming an overcoat layer directly on the pixel electrode. ≪ RTI ID = 0.0 > 11. < / RTI > 9. The method of claim 8,
Wherein the coloring material is doped to the conductive nanowire by a binder. 9. The method of claim 8,
The sub-pixel includes a red sub-pixel, a green sub-pixel, and a blue sub-pixel,
A first solution in which the conductive nanowire is doped with a red coloring material in the red sub-pixel by a printing method,
A second solution obtained by doping the conductive nanowire with a green coloring material on the green sub-pixel by a printing method,
And a third solution doped with the blue coloring material in the conductive nanowire is applied to the blue sub-
Wherein each of the pixel electrodes is formed on the gate insulating layer including the drain electrode of the sub-pixels. 9. The method of claim 8,
The sub-pixel includes a red sub-pixel, a green sub-pixel, and a blue sub-pixel,
In the step of forming the pixel electrode,
Depositing a first solution doped with a red color material on the conductive nanowire over the gate insulating layer and etching the first solution to form the pixel electrode connected to the drain electrode in the red sub-
Depositing a second solution doped with a green coloring material on the conductive nanowire over the gate insulating layer and etching the second solution to form the pixel electrode connected to the drain electrode in the green sub-
Wherein a third solution doped with a blue coloring material to the conductive nanowire is entirely deposited on the gate insulating layer and then etched to form the pixel electrode connected to the drain electrode in the blue sub- ≪ / RTI > The method according to claim 1,
Wherein the gate insulating layer is thinner than the protective layer. The method according to claim 1,
Wherein a transmission wavelength of light transmitted from the lower side of the substrate to the substrate side is determined by the coloring material in the pixel electrode positioned between the gate insulating film and the protective film in each of the plurality of sub-pixels. 9. The method of claim 8,
Wherein the terminal polar group of the conductive nanowire is a hydroxyl group.

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