KR20150051351A - Thin film transistor substrate and Display Device and Method of manufacturing the sames - Google Patents

Abstract

A thin film transistor substrate according to the present invention includes a transistor region which is formed on a substrate and has a thin film transistor formed by the vertical intersection of a gate line and a data line and a pixel region defined by an opening region except the transistor region, a first light shielding layer formed on the transistor region of the substrate, a second light shielding layer overlapped with the first light shielding layer under the substrate, an active layer formed on the first light shield layer, a thin film transistor which includes a gate electrode, a source electrode, and a drain electrode, and a pixel electrode which is connected to the drain electrode and is formed in the opening region. Visibility characteristic can be improved by reducing light (L) reflected to an opening area (OA) on the surface of a substrate (10).

Description

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

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film transistor substrate, and more particularly, to a thin film transistor substrate and a display device capable of reducing a light reflectance on a substrate surface, and a manufacturing method thereof.

Display devices such as a liquid crystal display device and an organic light emitting device include a thin film transistor substrate as an essential component. Specifically, the liquid crystal display device includes a thin film transistor substrate, a color filter substrate facing the thin film transistor substrate, and a liquid crystal layer formed between the both substrates, wherein the organic light emitting device includes a thin film transistor substrate, And a light emitting layer formed on the transistor substrate.

Hereinafter, a conventional thin film transistor substrate will be described with reference to the drawings.

1 is a schematic cross-sectional view of a conventional thin film transistor substrate.

As can be seen from Fig. 1, the conventional thin film transistor substrate comprises a transistor region TA and an opening region OA.

The transistor region TA includes a light blocking film 20, a buffer layer 30, an active layer 40, a gate insulating film 50, a gate electrode 60, an interlayer insulating film 70, And source and drain electrodes 80a and 80b.

A light shielding film 20 is patterned on the substrate 10 of the transistor region TA to shield the light L flowing into the active layer 40.

A buffer layer 40 is formed on the substrate 10 and the active layer 40 is patterned on the buffer layer 40. A gate insulating film 50 and a gate electrode 60 are patterned.

An interlayer insulating film 70 having contact holes H1 and H2 exposing a part of the active layer 40 is formed on the substrate 10 with the gate electrode 60 interposed therebetween.

The source and drain electrodes 80a and 80b are formed on the interlayer insulating layer 70 and are connected to the active layer 40 through the contact holes.

A protective film 90 is formed on the substrate 10 to expose a part of the drain electrode 80b and the protective film 90 is formed on the protective film 90 of the opening region OA. The pixel electrode 100 is formed to be connected to the drain electrode 80b through the contact hole H3.

The conventional thin film transistor substrate can block the light L flowing into the transistor region TA by forming the light shielding film 20 on the substrate 10, The luminous efficiency due to the light L reflected by the light source L is deteriorated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a thin film transistor substrate capable of improving luminous efficiency by reducing light L reflected from the surface of the substrate 10 to the opening area OA, And a display device and a method of manufacturing the same.

In order to achieve the above object, the present invention provides a liquid crystal display device including: a transistor region formed on a substrate and formed by a vertical intersection of a gate line and a data line, a pixel region defined by an opening region other than the transistor region, A second light shielding film formed on the first light shielding film to overlap the first light shielding film under the substrate, a thin film formed on the first light shielding film and including an active layer, a gate electrode, a source electrode and a drain electrode And a pixel electrode connected to the drain electrode and formed in the opening region.

The present invention also provides a method of fabricating a semiconductor device, comprising the steps of: texturing the surface of the substrate top surface of a transistor region; forming a first light blocking film on the substrate of the transistor region; Forming a thin film transistor on the first light blocking film, and forming a pixel electrode connected to the thin film transistor.

The thin film transistor substrate further includes a transistor region formed on the substrate and in which the thin film transistor is formed by vertical intersection of the gate line and the data line, A first light blocking film formed on the transistor region on the substrate, a second light blocking film formed on the substrate below the first light blocking film, an active layer formed on the first light blocking film, A thin film transistor including a source electrode and a drain electrode, and a pixel electrode connected to the drain electrode and formed in the opening region.

The present invention also provides a method of manufacturing a thin film transistor substrate, comprising the steps of: forming a transistor region formed on a substrate and in which a thin film transistor is formed by vertical intersection of a gate line and a data line; A pixel region defined by an opening region other than the transistor region, a first light blocking film formed on the transistor region on the substrate, a second light blocking film formed on the substrate below the first light blocking film, A thin film transistor including an active layer, a gate electrode, a source electrode, and a drain electrode, and a pixel electrode connected to the drain electrode and formed in the opening region.

According to the present invention as described above, the following effects can be obtained.

The present invention can reduce the light L reflected from the surface of the substrate 10 to the opening area OA by forming a light shielding film below the substrate 10 of the transistor area TA to improve the visual sensitivity.

1 is a schematic cross-sectional view of a conventional thin film transistor substrate.
2 is a schematic plan view of a thin film transistor substrate according to an embodiment of the present invention.
3 is a schematic cross-sectional view of a thin film transistor substrate according to an embodiment of the present invention.
4 is a schematic cross-sectional view of a thin film transistor substrate according to another embodiment of the present invention.
5 is a schematic cross-sectional view of a thin film transistor substrate according to another embodiment of the present invention.
6A to 6G are schematic manufacturing process diagrams of a thin film transistor substrate according to an embodiment of the present invention.
7 is a schematic cross-sectional view of an organic light emitting device according to an embodiment of the present invention.
8 is a schematic cross-sectional view of a liquid crystal display device according to an embodiment of the present invention.

The term "on " as used herein is meant to encompass not only when a configuration is formed directly on top of another configuration, but also to the extent that a third configuration is interposed between these configurations.

As used herein, the term "coupled" is intended to include not only the case where a configuration is directly connected to another configuration but also the case where a configuration is indirectly connected to another configuration through a third configuration.

The modifiers such as " first "and " second" described in the present specification do not mean the order of the corresponding configurations, but are intended to distinguish the corresponding configurations from each other.

As used herein, the phrase " the patterns are the same "should be construed to include not only the case where the patterns of other structures are completely identical to each other, but also the case where the pattern is distorted.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise.

It is to be understood that the term " comprising, "as used herein, is intended to specify the presence of stated features, integers, steps, operations, elements, And does not preclude the presence or addition of one or more other elements, components, components, parts, or combinations thereof.

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

FIG. 2 is a schematic plan view of a thin film transistor substrate according to an embodiment of the present invention, and FIG. 3 is a schematic cross-sectional view of a thin film transistor substrate according to an embodiment of the present invention.

2 and 3, a pixel region is formed on the substrate 100 by vertical intersection of the data line DL and the gate line GL. The pixel region is defined as a transistor region TA where a thin film transistor is formed and an opening region OA other than the transistor region TA.

The transistor region TA includes a substrate 100, a first light blocking film 200, a second light blocking film 250, and a thin film transistor TFT.

Glass is mainly used for the substrate 100, but transparent plastic such as polyimide which can bend or tear can be used. When polyimide is used as the material of the substrate 100, polyimide excellent in heat resistance that can withstand high temperatures can be used, considering that a high temperature deposition process is performed on the substrate 100.

When light is incident on the substrate 100, some light may be reflected from the surface of the substrate 100 into the opening area OA, thereby deteriorating the visual sensation characteristics.

The first light blocking layer 200 is formed on the substrate 100 and the second light blocking layer 250 is formed under the substrate 100 so as to overlap with the first light blocking layer 200.

The first light shielding film 200 may block light flowing into the transistor TFT.

The first light blocking layer 200 may be formed of a material capable of absorbing and blocking light, and may be formed of, for example, amorphous silicon or amorphous germanium.

The second light shielding film 250 is formed under the substrate 100 in the same pattern as the first light shielding film 200 and the second light shielding film 250 is formed of a material capable of absorbing and blocking light For example, amorphous silicon or amorphous germanium.

At this time, by forming a light shielding film below the substrate 100 of the transistor area TA, the light reflected from the surface of the substrate 100 to the opening area OA is reduced,

More specifically, the second light shielding film 250, which is capable of absorbing and blocking the light below the substrate 100, is formed in the transistor area TA, thereby reducing the light entering the substrate 100, The light reflected from the surface of the substrate 100 to the opening area OA is also reduced, so that the visual sensitivity can be improved.

The thin film transistor (TFT) is formed on the first light blocking film 200.

The thin film transistor TFT includes a buffer layer 300, an active layer 400, a gate insulating film 500, a gate electrode 600, an interlayer insulating film 700, and source and drain electrodes 800a and 800b .

The buffer layer 300 is formed on the substrate 100 including the first light blocking layer 200.

When the thin film transistor according to the present invention is applied to the organic light emitting device, the buffer layer 300 may prevent external moisture or moisture from penetrating into the organic light emitting device. The buffer layer 300 may be formed of silicon oxide or silicon nitride.

The active layer 400 is formed on the first light blocking layer 200 and the second light blocking layer 250.

The active layer 400 may be formed of an oxide semiconductor such as In-Ga-Zn-O (IGZO), but the present invention is not limited thereto.

A gate insulating film 500 and a gate electrode 600 are patterned in this order on the active layer 400.

The gate insulating layer 500 may be formed of an inorganic insulating material such as silicon oxide or silicon nitride. However, the gate insulating layer 500 may be formed of an organic insulating material such as photo acryl or benzocyclobutene (BCB) have. The gate insulating layer 500 serves to insulate the gate electrode 600 from the active layer 400.

The gate electrode 600 may be formed of at least one selected from the group consisting of Mo, Al, Cr, Au, Ti, Ni, Alloy, and may be composed of a single layer of the metal or alloy or multiple layers of two or more layers.

The interlayer insulating layer 700 includes a first contact hole H1 and a second contact hole H2 on the substrate 100 to expose a part of the active layer 400 and a pattern is formed thereon.

The first contact hole H1 is formed on one side of the active layer 400 so that the source electrode 800a and the active layer 400 are connected to each other. The second contact hole H2 is formed on the other side of the active layer 400 so that the drain electrode 800b and the active layer 400 are connected to each other.

The interlayer insulating layer 700 may be formed of silicon oxide or silicon nitride.

The source and drain electrodes 800a and 800b are formed on the substrate 100 in the transistor region TA and are connected to the active layer 400. [

The source electrode 800a is connected to the active layer 400 through the first contact hole H1 and the drain electrode 800b is connected to the active layer 400 through the second contact hole H2. Lt; / RTI >

The source and drain electrodes 800a and 800b may be formed of one selected from the group consisting of Mo, Al, Cr, Au, Ti, Ni, Cu, or an alloy thereof, and may be a single layer of the metal or alloy, or multiple layers of two or more layers.

A protective film 900 is formed on the source and drain electrodes 800a and 800b. The passivation layer 900 includes a third contact hole H3 for exposing a portion of the drain electrode 800b.

The protective film 900 may be made of an inorganic insulating material such as silicon oxide or silicon nitride, but is not limited thereto.

The pixel electrode 1000 is formed on the protective film 900 and is connected to the drain electrode 800b through the third contact hole H3.

The pixel electrode 1000 may be formed of a transparent metal oxide such as ITO.

FIG. 4 is a schematic cross-sectional view of a thin film transistor substrate according to another embodiment of the present invention, and is the same as the thin film transistor substrate according to FIG. 3 except that the structure of the second light shielding film 250 is changed. Therefore, the same reference numerals are assigned to the same components, and repetitive description of the same components will be omitted.

Referring to FIG. 4, the second light blocking layer 250 is formed under the substrate 100 in the same pattern as the first light blocking layer 200.

At this time, the second light blocking layer 250 may be formed to be shorter than the first light blocking layer 200.

That is, if the length b of the first light blocking layer 200 is equal to the length a of the second light blocking layer 250, the length b of the first light blocking layer 200, The light viewing angle corresponding to the difference of the length a of the shielding film 250 can be reduced.

Therefore, in the thin film transistor substrate according to another embodiment of the present invention, the length (a) of the second light shielding film 250 is shorter than that of the first light shielding film 200, There is an effect that the viewing angle is not reduced.

5 is a schematic cross-sectional view of a thin film transistor substrate according to another embodiment of the present invention, and is the same as the thin film transistor substrate according to the above-described FIG. 3 except that the structure of the substrate 100 is changed. Therefore, the same reference numerals are assigned to the same components, and repetitive description of the same components will be omitted.

Referring to FIG. 5, the surface of the upper surface of the substrate 100, which overlaps with the first light shielding film 200, has a textured texture feature 110.

A textured feature 110 is formed on the upper surface of the substrate 100 by texturing the surface of the upper surface of the substrate 100 that overlaps with the first light shielding film 200, The light reflectance reflected from the substrate 100 can be reduced and the light reflected from the surface of the substrate 100 to the opening area OA can be reduced to improve the visual sensitivity.

Hereinafter, repetitive description of the repetitive portions in the materials, structures and the like of each constitution will be omitted.

6A to 6G are schematic manufacturing process diagrams of a thin film transistor substrate according to an embodiment of the present invention.

Referring to FIG. 6A, a textured feature 110 is formed on the upper surface of the substrate 100 of the transistor region TA.

The upper surface of the substrate 100 of the transistor region TA may be textured by Alkaline etching or Acid etching to form the textured features 110. In addition, the surface of the substrate 100 may be scraped off using a laser or a diamond blade, and then the etching solution may be treated to form the textured features 110.

Next, referring to FIG. 6B, a first light shielding film 200 is patterned on the substrate 100 of the transistor region TA.

The first light blocking layer 200 may be formed by depositing amorphous silicon or amorphous germanium using PECVD (Plasma Enhanced Chemical Vapor Deposition), forming a photoresist pattern on the deposited amorphous silicon or amorphous germanium, The pattern can be formed by using a mask process that sequentially performs the process. Pattern formation for each structure described below can also be performed using a mask process including the above-described exposure, development and etching processes

Thereafter, the second light shielding film 250 may be formed under the substrate 100 in the same pattern as the first light shielding film 200.

Although not shown, as another embodiment, the second light shielding film 250 may be patterned after forming the thin film transistor substrate according to the present invention.

6C, a buffer layer 300 is deposited on the substrate 100 including the first light shielding layer 200, and then an active layer (not shown) is formed on the first light shielding layer 200. Then, (400).

6D, a gate insulating layer 500 is deposited on the substrate 100 including the active layer 400, a gate electrode material is deposited on the gate insulating layer 500, The gate insulating film 500 and the gate electrode 600 are pattern-formed.

6E, a first contact hole H1 for exposing a part of the active layer 400 on the substrate 100 and an interlayer insulating film 700 for providing a second contact hole H2 Pattern formation.

Referring to FIG. 6F, the source and drain electrodes 800a and 800b are patterned to be connected to the active layer 400 on the substrate 100 in the transistor region TA.

6G, a protective film 900 is patterned to have a third contact hole H3 for exposing a part of the drain electrode 800b on the source and drain electrodes 800a and 800b. do.

Thereafter, the pixel electrode 1000 is patterned to be connected to the drain electrode 800b through the third contact hole H3 on the passivation layer 900. Next, as shown in FIG.

FIG. 7 is a schematic cross-sectional view of an organic light emitting device according to an embodiment of the present invention, which is related to the organic light emitting device to which the thin film transistor substrate according to FIG. 3 is applied.

As shown in FIG. 7, the organic light emitting device according to an embodiment of the present invention includes the thin film transistor substrate according to the above-described FIG. 3, and includes a bank layer 1100, a light emitting portion 1200, And an upper electrode (1300).

The bank layer 1100 is formed on the protective film 900. Specifically, the bank layer 1100 is formed above the source electrode 800a and the drain electrode 800b, and particularly formed in the transistor region TA. That is, the opening area OA for displaying an image is surrounded by the bank layer 1100. [

The bank layer 1100 may be formed of an organic insulating material such as polyimide, photo acryl, or benzocyclobutene (BCB), but the present invention is not limited thereto.

The light emitting portion 1200 is formed on the pixel electrode 1000. Although not shown, the light emitting unit 1200 may have a structure in which a hole injecting layer, a hole transporting layer, an organic light emitting layer, an electron transporting layer, and an electron injecting layer are sequentially stacked. However, one or two or more layers of the hole injection layer, the hole transport layer, the electron transport layer, and the electron injection layer may be omitted. The light emitting unit 1200 may be modified into various forms known in the art, in addition to the combination of layers as described above.

The upper electrode 1300 is formed on the light emitting unit 1200. The upper electrode 1300 may function as a common electrode and may be formed on the entire surface of the substrate including the bank layer 1100 as well as the light emitting portion 1200.

The upper electrode 1300 may be formed of a metal such as silver (Ag), but is not limited thereto.

The organic light emitting device according to the present invention as shown in FIG. 7 is manufactured by forming the thin film transistor substrate on the protective layer 900 above the source electrode 800a and the drain electrode 800b, And the upper electrode 1300 is formed on the light emitting portion 1200. The light emitting portion 1200 may be formed by patterning the bank layer 1100 on the pixel electrode 1000, patterning the light emitting portion 1200 on the pixel electrode 1000, do.

Although not shown, a manufacturing method of an organic light emitting device to which the method for manufacturing a thin film transistor according to the above-described Figs. 6A to 6G is applied is also within the scope of the present invention.

8 is a schematic cross-sectional view of a liquid crystal display device according to an embodiment of the present invention, which relates to a liquid crystal display device to which the thin film transistor according to the above-described FIG. 3 is applied.

8, the liquid crystal display device according to an embodiment of the present invention includes the thin film transistor substrate according to the above-described FIG. 3, the opposing substrate 1400 facing the thin film transistor substrate, Layer 1500 as shown in FIG.

Although not shown, a common electrode for forming an electric field for liquid crystal driving together with the pixel electrode 1000 may be additionally formed on the thin film transistor substrate.

The counter substrate 1400 may include a light shielding layer and a color filter layer although not shown.

The light shielding layer is formed in a matrix structure in order to block leakage of light to regions other than the pixel region, and the color filter layer is formed in the region between the light shielding layers of the matrix structure.

The liquid crystal display according to the present invention can be applied to liquid crystal display devices of various modes known in the art such as TN (Twisted Nematic) mode, VA (Vertical Alignment) mode and IPS (In-Plane Switching) mode.

The liquid crystal display according to FIG. 8 has the same structure as the liquid crystal display according to the first embodiment except that the thin film transistor substrate is manufactured by the process according to the above-described FIGS. 6A to 6G, the counter substrate 14000 is manufactured, And the two substrates are bonded together.

The process of attaching the two substrates may be performed using a vacuum injection method or a liquid dropping method known in the art.

Although not shown, a manufacturing method of a liquid crystal display device to which the method for manufacturing a thin film transistor according to the above-described Figs. 6A to 6G is applied is also within the scope of the present invention.

It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof.

For example, in the above-described embodiments, the buffer layer 300 is essentially included. However, in the modified embodiment, the buffer layer 300 may be omitted. In this case, the active layer 400 is directly formed on the first light blocking film 200.

It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

100: substrate 200: first light blocking film
250: second light blocking film 300: buffer layer
TFT: transistor 400: active layer
500: gate insulating film 600: gate electrode
700: interlayer insulating film 800a: source electrode
800b: drain electrode 900: protective film
1000: pixel electrode H1: first contact hole
H2: second contact hole H3: third contact hole

Claims (10)

A pixel region formed on the substrate and defined by a transistor region in which a thin film transistor is formed by vertical intersection of a gate line and a data line and an opening region other than the transistor region;
A first light blocking film formed in the transistor region on the substrate;
A second light blocking film formed on the substrate under the first light blocking film;
A thin film transistor formed on the first light blocking film and including an active layer, a gate electrode, a source electrode, and a drain electrode; And
And a pixel electrode connected to the drain electrode and formed in the opening region. The method according to claim 1,
Wherein the second light-blocking film is shorter than the first light-blocking film. The method according to claim 1,
Wherein the first light-blocking film and the second light-blocking film are made of amorphous silicon or amorphous germanium. The method according to claim 1,
Wherein a surface of the substrate upper surface overlapping the first light shielding film has textured textural features. Texturing the surface of the substrate upper surface of the transistor region;
Forming a first light shielding film on the substrate of the transistor region and forming a second light shielding film in an area overlapping the first light shielding film below the substrate;
Forming a thin film transistor on the first light blocking film; And
And forming a pixel electrode connected to the thin film transistor. 6. The method of claim 5,
Wherein the second light-blocking film has a shorter length than the first light-blocking film. 6. The method of claim 5,
Wherein the first light-blocking film and the second light-blocking film are made of amorphous silicon or amorphous germanium. 6. The method of claim 5,
Wherein the surface of the upper surface of the substrate overlapping the first light shielding film has textured textural features. A thin film transistor substrate,
In the thin film transistor substrate,
A pixel region formed on the substrate and defined by a transistor region in which a thin film transistor is formed by vertical intersection of a gate line and a data line and an opening region other than the transistor region;
A first light blocking film formed in the transistor region on the substrate;
A second light blocking film formed on the substrate under the first light blocking film;
A thin film transistor formed on the first light blocking film and including an active layer, a gate electrode, a source electrode, and a drain electrode; And
And a pixel electrode connected to the drain electrode and formed in the opening region. And a method of manufacturing a thin film transistor substrate,
A method of manufacturing a thin film transistor substrate,
A pixel region formed on the substrate and defined by a transistor region in which a thin film transistor is formed by vertical intersection of a gate line and a data line and an opening region other than the transistor region;
A first light blocking film formed in the transistor region on the substrate;
A second light blocking film formed on the substrate under the first light blocking film;
A thin film transistor formed on the first light blocking film and including an active layer, a gate electrode, a source electrode, and a drain electrode; And
And a pixel electrode connected to the drain electrode and formed in the opening region.

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