KR20150035307A - Organic light emitting display device and method for manufacturing of the same - Google Patents

Abstract

An organic electroluminescent display device according to an embodiment of the present invention includes a substrate and a pixel region that includes a light emitting part and a transparent part. The light emitting part includes a thin film transistor and a pixel electrode. The transparent part includes a capacitor, and the capacitor consists of two transparent electrodes.

Description

TECHNICAL FIELD [0001] The present invention relates to an organic electroluminescent display device,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to an organic light emitting display device, and more particularly, to a transparent organic light emitting display device capable of widening the area of a transparent portion and a method of manufacturing the same.

Flat panel displays (FPDs) are becoming increasingly important with the development of multimedia. For example, a liquid crystal display (LCD), a plasma display panel (PDP), a field emission display (FED), an organic light emitting display Various flat-panel displays have been put into practical use. Among them, the liquid crystal display device is superior in visibility to a cathode ray tube, has a small average power consumption and a small calorific value, and the organic light emitting display has a response speed of 1 ms or less and a high response speed, , There is no problem in the viewing angle since it is self-luminescence, and it is attracting attention as a next generation flat panel display device.

In recent years, transparent organic light emitting display devices have been actively developed. The transparent organic electroluminescent display device has a transparent portion which has a minimum light emitting portion and the remaining region can transmit light as it is, thereby realizing a transparent organic electroluminescent display device.

FIG. 1 is a plan view of a conventional organic light emitting display device, and FIG. 2 is a cross-sectional view illustrating an organic light emitting display device.

Referring to FIG. 1, a conventional organic light emitting display includes a plurality of subpixels SP divided into a data line DL and a gate line GL. For example, one subpixel SP consists of a light emitting portion EP for emitting light and a transparent portion TP for transmitting light. The light emitting portion EP includes a switching thin film transistor S-TFT, a driving thin film transistor D-TFT, a capacitor Cst, and a pixel electrode PX. The driving thin film transistor D-TFT includes a source electrode SE connected to a power supply line VD and a drain electrode DE, and the pixel electrode PX is connected to the drain electrode DE. Nothing is formed in the transparent portion TP to increase the light transmittance.

2, a light emitting unit EP, a capacitor unit Cst, a transparent unit TP, and a pad unit PP are defined on a substrate SUB in an organic light emitting display device. Referring to FIG. The first gate electrode 10, the lower capacitor electrode 12 and the first pad electrode 14 are positioned on the substrate SUB and the gate insulating film 16 for insulating them is located. The semiconductor layer 20 and the etch stopper 25 are located on the first gate electrode 10 and the source electrode 32 and the drain electrode 34 connected to the semiconductor layer 20 are located. The metal pattern 30 is connected to one side of the first gate electrode 10 and the drain electrode 34 is connected to the lower capacitor electrode 12 and the middle capacitor electrode 36 is located on the lower capacitor electrode 12 do. A second pad electrode 38 is connected to the first pad electrode 14 and a protective film 50 for insulating them is located.

A second gate electrode 42 corresponding to the first gate electrode 10 is connected to the metal pattern 30 and an upper capacitor electrode 44 connected to the drain electrode 34 constitutes a capacitor, . A third pad electrode 46 connected to the second pad electrode 38 is located in the pad portion PP. The overcoat layer 50 exposing the upper capacitor electrode 44 is located in an area other than the pad part PP. A pixel electrode 55 is formed on the exposed upper capacitor electrode 44 and a fourth pad electrode 57 connected to the third pad electrode 46 is located. Then, the reflective film 60 is positioned on the pixel electrode 55.

However, the conventional organic light emitting display device has a problem that transparency is reduced as a transparent display due to a small transparent region due to the capacitor portion Cst.

The present invention provides an organic electroluminescent display device and a method of manufacturing the same, which can increase the reliability of a transparent display by enlarging the area of the transparent portion.

According to an aspect of the present invention, there is provided an organic light emitting display including a substrate, a pixel region disposed on the substrate and including a light emitting portion and a transparent portion, And a pixel electrode, wherein the transparent portion includes a capacitor, and the capacitor is formed of two transparent electrodes.

The thin film transistor includes a first gate electrode located on the substrate, a semiconductor layer located on the gate electrode, a source electrode and a drain electrode connected to the semiconductor layer, and a second gate electrode located on the semiconductor layer .

The capacitor including the two transparent electrodes includes a first capacitor electrode and a second capacitor electrode connected to the drain electrode.

And the pixel electrode is connected to the drain electrode, and is integrated with the second capacitor electrode.

According to another aspect of the present invention, there is provided a method of manufacturing an organic light emitting display, including: preparing a substrate having a pixel region including a light emitting portion and a transparent portion; Forming a first protective film on the thin film transistor, sequentially stacking a transparent conductive material and a metal material on the first protective film, Forming a second gate electrode and a first capacitor electrode connected to the first gate electrode, forming a second protective film on the second gate electrode and the first capacitor electrode, Forming an overcoat layer on the second protective film corresponding to the light emitting portion, and forming an overcoat layer on the overcoat layer, After stacking a metal material characterized by including the step of selectively removing and patterning the metal material, forming the pixel electrode and the reflective film being connected to the drain electrode in the region other than the light emitting portion.

The pixel electrode functions as a second capacitor electrode integrally formed with the light emitting portion and the transparent portion and serving as a pixel electrode in the light emitting portion and forming a capacitance with the first capacitor electrode in the transparent portion do.

The step of forming the second gate electrode and the first capacitor electrode and the reflective film with the pixel electrode is performed by a diffraction exposure method using a halftone mask.

An organic light emitting display and a method of manufacturing the same according to an embodiment of the present invention have an advantage that transparency and reliability as a transparent display can be improved by enlarging an area of a transparent portion by forming a capacitor by using transparent electrodes.

1 is a plan view of a conventional organic electroluminescence display device.
2 is a cross-sectional view of a conventional organic light emitting display device.
3 is a plan view of an organic light emitting display according to an embodiment of the present invention.
4 is a cross-sectional view illustrating an organic light emitting display device according to a first embodiment of the present invention.
5A to 5J are views illustrating a method of manufacturing an organic light emitting display according to a first embodiment of the present invention.
6 is a cross-sectional view illustrating an organic light emitting display device according to a second embodiment of the present invention.

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

FIG. 3 is a plan view showing an organic light emitting display according to an embodiment of the present invention, and FIG. 4 is a cross-sectional view illustrating an organic light emitting display according to a first embodiment of the present invention.

Referring to FIG. 3, an organic light emitting display according to an exemplary embodiment of the present invention includes a plurality of sub-pixels SP divided into a data line DL and a gate line GL. One subpixel SP includes, for example, a light emitting portion (EP) and a transparent portion (TP) through which light is emitted. The light emitting portion EP includes a switching thin film transistor (S-TFT), a driving thin film transistor (D-TFT), and a pixel electrode 170.

More specifically, the light-emitting portion EP includes a driving thin film transistor (D-TFT) including a first gate electrode 112, a semiconductor layer (not shown), a source electrode 132 and a drain electrode 134. And the pixel electrode 170 is connected to the drain electrode 134 of the driving thin film transistor (D-TFT). The transparent portion TP includes a capacitor Cst and an area in which nothing adjacent to the light emitting portion EP is formed between the power supply line VL. The capacitor Cst formed in the transparent portion TP includes a first capacitor electrode 144 and a second capacitor electrode 170 formed integrally with the pixel electrode 170. The first capacitor electrode 144 and the second capacitor electrode 170 are made of transparent electrodes and function as a transparent portion TP through which light is transmitted.

4, the organic light emitting display device 100 according to the first embodiment of the present invention includes a substrate 100 on which a light emitting unit EP, a transparent unit TP, and a pad unit PP are partitioned The first gate electrode 112 and the first pad electrode 114 are located on the first gate electrode 110. The first gate electrode 112 is located at the light emitting portion EP and the first pad electrode 114 is located at the pad portion PP. A gate insulating layer 120 is formed on the first gate electrode 112 and the first pad electrode 114 to isolate the first gate electrode 112 and the first pad electrode 114 from each other. The semiconductor layer 124 is located on the gate insulating film 120 in a region corresponding to the first gate electrode 112 and the etch stopper 126 is located on the semiconductor layer 124. A source electrode 132 and a drain electrode 134 connected to both sides of the semiconductor layer 124 are positioned and connected to the first gate electrode 112 through a first contact hole CH1 formed in the gate insulating layer 120. [ The metal pattern 130 is located. The second pad electrode 136 is positioned on the first pad electrode 114 of the pad portion PP through the second contact hole CH2 formed on the gate insulating layer 120. [

A first protective film 140 for insulating the source electrode 132 and the drain electrode 134, the metal pattern 130, and the second pad electrode 136 is located. The second gate electrode 148 connected to the metal pattern 130 is positioned through the third contact hole CH3 formed in the first protective film 140. [ The second gate electrode 148 is composed of the first transparent layer 142 and the metal layer 146 and is positioned to correspond to the first gate electrode 112 and overlapped with the semiconductor layer 124. A first capacitor electrode 144 is located on the first protective film 140 of the transparent portion TP. The second pad electrode 136 of the pad portion PP is exposed by the fifth contact hole CH5 formed in the first protective layer 140 for connection with the third pad electrode 172. [

A second protective film 150 for insulating the second gate electrode 148, the first capacitor electrode 144, and the second pad electrode 136 is disposed. A sixth contact hole CH5 exposing the drain electrode 134 is located in the second passivation layer 150 and a seventh contact hole CH5 exposing the second pad electrode 136 exposed by the fifth contact hole CH5. (CH7). The overcoat layer 160 is positioned on the second protective film 150 of the light emitting part EP to flatten the bottom step. The overcoat layer 160 is not located in the transparent portion TP and the pad portion PP in addition to the light emitting portion EP.

The pixel electrode 170 connected to the drain electrode 134 exposed through the sixth contact hole CH6 is located on the overcoat layer 160 and the second passivation layer 150. [ The pixel electrode 170 is integrally formed over the overcoat layer 160 of the light emitting portion EP to the upper portion of the first capacitor electrode 144 of the transparent portion TP. Accordingly, the pixel electrode 170 functions as the first capacitor electrode 144 and the corresponding second capacitor electrode. The pixel electrode 170 includes a transparent electrode through which light is transmitted, and a capacitor including the first capacitor electrode 144 and the second capacitor electrode acts as a transparent portion TP. A third pad electrode 172 made of the same material as the pixel electrode 170 is connected to the second pad electrode 136 in the pad portion PP. The reflective film 180 is positioned on the pixel electrode 170 and the light emitted from the light emitting layer (not shown) is reflected upward. As described above, the organic light emitting display device 100 according to an embodiment of the present invention can be configured.

Hereinafter, a method of manufacturing the organic light emitting display device according to the first embodiment of the present invention will be described. In the following description, the same constituent elements as those in Fig. 4 described above are denoted by the same reference numerals, thereby facilitating understanding. 5A to 5J are views illustrating a method of manufacturing an organic light emitting display according to a first embodiment of the present invention.

5A, aluminum (Al), molybdenum (Mo), tungsten (W), titanium (Ti), or an alloy thereof is deposited on a substrate 110 made of glass, A first gate electrode 112 and a first pad electrode 114 are formed by patterning using a mask. At this time, the first gate electrode 112 and the first pad electrode 114 may be a single layer made of the above-mentioned material and may be made of molybdenum / aluminum / molybdenum (Mo / Al / Mo) or titanium / aluminum / titanium / Ti). ≪ / RTI >

5B, a gate insulating layer 120 is formed on a substrate 110 having a first gate electrode 112 and a first pad electrode 114 formed thereon. The gate insulating film 120 is formed of silicon oxide (SiOx), silicon nitride (SiNx), or a stacked structure thereof. Amorphous silicon, polycrystalline silicon, or metal oxide is deposited on the gate insulating layer 120 corresponding to the first gate electrode 112 and then patterned using a second mask to form the semiconductor layer 124.

5C, silicon oxide (SiO x) or silicon nitride (SiN x) is deposited on the substrate 110 on which the semiconductor layer 124 is formed and patterned using a third mask to form the etch stopper 126 . The etch stopper 126 is formed to correspond to the semiconductor layer 124.

Referring to FIG. 5D, a portion of the gate insulating layer 120 is etched using the fourth mask to form a first contact hole CH1 exposing one side of the first gate electrode 112. Next, as shown in FIG. At the same time, a second contact hole CH2 exposing one side of the first pad electrode 114 is formed.

5e, molybdenum (Mo), tungsten (W), titanium (Ti), and aluminum (Al) are sequentially stacked on a substrate 110 on which a first contact hole CH1 and a second contact hole CH2 are formed. A source electrode 132, a drain electrode 134, and a second pad electrode 136 are formed by depositing a metal layer or an alloy thereof and patterning the metal layer 130, the source electrode 132, the drain electrode 134 and the second pad electrode 136 using a fifth mask. Here, the metal pattern 130 is connected to the first gate electrode 112 exposed through the first contact hole CH1. The source electrode 132 and the drain electrode 134 are connected to both sides of the semiconductor layer 124, respectively. The second pad electrode 136 is connected to the first pad electrode 114 through the second contact hole CH2.

5f, a silicon oxide (SiOx), a silicon nitride (SiNx), a silicon nitride (SiNx), and a silicon nitride (SiOx) are sequentially stacked on a substrate 110 on which a metal pattern 130, a source electrode 132, a drain electrode 134 and a second pad electrode 136 are formed. SiNx) or a multi-layered structure thereof to form a first protective film 140. The first protective film 140 is etched using the sixth mask to form a third contact hole CH3 exposing the metal pattern 130 and a fifth contact hole CH5 exposing the second pad electrode 136 ).

Next, referring to FIG. 5G, a transparent conductive material and a metal material are sequentially stacked on the substrate 110 on which the third contact hole CH3 and the fifth contact hole CH5 are formed. The transparent conductive material may be indium tin oxide (ITO), indium zinc oxide (IZO), or indium tin zinc oxide (ITZO). The metal material may be aluminum (Al), molybdenum (Mo), tungsten (W) ) Or alloys thereof. Next, the transparent conductive material and the metal material are patterned using a halftone mask, which is a seventh mask, to form the second gate electrode 148, the first capacitor electrode 144, and the third pad electrode 172 . The second gate electrode, the first capacitor electrode 144, and the third pad electrode 172 are formed by applying a photoresist on the substrate 110, aligning the halftone mask, and then using a diffraction exposure method. At this time, the second gate electrode 148 has a structure in which the transparent layer 142 and the metal layer 146 are laminated, and the first capacitor electrode 144 and the third pad electrode 172 are formed only of the transparent layer from which the metal layer is removed .

5H, a silicon oxide (SiOx), a silicon nitride (SiNx), and a silicon nitride (SiNx) are sequentially stacked on a substrate 110 on which a second gate electrode 148, a first capacitor electrode 144 and a third pad electrode 172 are formed. Or the second protective film 150 is formed by laminating them in multiple layers. The second passivation layer 150 and the first passivation layer 140 are etched using the eighth mask to form a sixth contact hole CH6 exposing the drain electrode 134. At the same time, The seventh contact hole CH7 exposing the third pad electrode 172 is formed.

Next, referring to FIG. 5I, an overcoat layer 160 is formed on a substrate 110 having a sixth contact hole CH6 and a seventh contact hole CH7. The overcoat layer 160 is made of a transparent polymer resin, and may be made of, for example, polyimide (PI) or polyacrylate (PA). Next, the overcoat layer 160 is etched using the ninth mask to remove the overcoat layer 160 between the transparent part TP and the pad part PP excluding the light emitting part EP.

Referring to FIG. 5J, a transparent conductive material and a metal material are sequentially stacked on the substrate 110 on which the overcoat layer 160 is formed. The transparent conductive material may be indium tin oxide (ITO), indium zinc oxide (IZO), or indium tin zinc oxide (ITZO). The metal material may be aluminum (Al), molybdenum (Mo), tungsten (W) ) Or alloys thereof. Next, the pixel electrode 170 and the reflective layer 180 are formed by patterning the transparent conductive material and the metal material using a halftone mask, which is a tenth mask. More specifically, the reflective film 180 is left only in the light-emitting portion EP and the reflective film 180 is removed in the remaining region by using the diffraction exposure technique using a halftone mask so that only the pixel electrode 170, which is a transparent conductive material, . At this time, the pixel electrode 170 formed on the transparent portion TP functions as the first capacitor electrode 144 and the second capacitor electrode forming the electrostatic capacitance. Therefore, the capacitor Cst of the present invention is composed of the first capacitor electrode 144 and the second capacitor electrode made of a transparent conductive material, and can act as the transparent portion TP.

Meanwhile, in the present invention, the pixel electrode 170 and the second capacitor electrode may be separately formed. 6 is a cross-sectional view illustrating an organic light emitting display device according to a second embodiment of the present invention. In the following, the same constituent elements as those of FIG. 4 described above are denoted by the same reference numerals, and a description thereof will be omitted.

6, the organic light emitting display according to the second embodiment of the present invention includes a second capacitor 150 connected to a drain electrode 134 exposed through a sixth contact hole CH6, The electrode 175 is positioned. The second capacitor electrode 175 is made of the same transparent material as the first capacitor electrode 144 described above. The overcoat layer 160 is disposed on the second capacitor electrode 175 and the second passivation layer 150. The drain electrode 134 and the drain electrode 134 exposed through the sixth contact hole CH6 are formed on the overcoat layer 160, The pixel electrode 170 connected to the second capacitor electrode 175 is located. The pixel electrode 170 is located on the overcoat layer 160 of the light emitting portion EP and the second capacitor electrode 175 is located on the first capacitor electrode 144 in the transparent portion TP. In the first embodiment described above, the pixel electrode 170 is integrated with the second capacitor electrode to perform both the pixel electrode and the second capacitor electrode. In the second embodiment, however, the pixel electrode 170 and the second capacitor Electrodes 175 are individually formed and electrically connected.

The method of manufacturing the organic light emitting display device according to the second embodiment of the present invention will be described with reference to FIG. 5H. After forming the second protective film 150 shown in FIG. 5H of the first embodiment, A transparent conductive material is deposited and patterned to form a second capacitor electrode 175 connected to the drain electrode 134 exposed by the sixth contact hole CH6 and corresponding to the first capacitor electrode 144. [ Thereafter, an overcoat layer 160 is formed on the substrate, and a pixel electrode 170 connected to the drain electrode 134 is formed on the overcoat layer 160. Finally, a reflective film 180 is formed on the pixel electrode 170 to manufacture an organic light emitting display.

As described above, the organic light emitting display device and the method of manufacturing the same according to embodiments of the present invention can improve the transparency and reliability as a transparent display by enlarging the area of the transparent part by forming a capacitor with transparent electrodes, There is an advantage.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood that the invention may be practiced. It is therefore to be understood that the embodiments described above are to be considered in all respects only as illustrative and not restrictive. In addition, the scope of the present invention is indicated by the following claims rather than the detailed description. Also, all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

100: organic electroluminescent display device 110: substrate
112: first gate electrode 124: semiconductor layer
126: etch stopper 132: source electrode
134: drain electrode 144: first capacitor electrode
148: second gate electrode 170: pixel electrode
180:

Claims (7)

Board; And
A pixel region located on the substrate and including a light emitting portion and a transparent portion,
Wherein the light emitting portion includes a thin film transistor and a pixel electrode,
Wherein the transparent portion includes a capacitor, and the capacitor comprises two transparent electrodes.
The method according to claim 1,
The thin film transistor includes a first gate electrode located on the substrate, a semiconductor layer located on the gate electrode, a source electrode and a drain electrode connected to the semiconductor layer, and a second gate electrode located on the semiconductor layer The organic light emitting display device comprising:
3. The method of claim 2,
Wherein the capacitor including the two transparent electrodes comprises a first capacitor electrode and a second capacitor electrode connected to the drain electrode.
The method of claim 3,
Wherein the pixel electrode is connected to the drain electrode and is integrated with the second capacitor electrode.
Preparing a substrate on which a pixel region including a light emitting portion and a transparent portion is partitioned;
Forming a thin film transistor including a first gate electrode, a semiconductor layer, a source electrode, and a drain electrode in the light emitting portion;
Forming a first protective film on the thin film transistor;
A transparent conductive material and a metal material are sequentially deposited on the first protective film, and then the metal material corresponding to the transparent portion is selectively removed and patterned to form a second gate electrode connected to the first gate electrode, Forming an electrode;
Forming a second protective film on the second gate electrode and the first capacitor electrode;
Forming an overcoat layer on the second protective film corresponding to the light emitting portion; And
Depositing a transparent conductive material and a metal material on the overcoat layer sequentially and then selectively removing and patterning the metal material in a region other than the light emitting portion to form a pixel electrode and a reflective film connected to the drain electrode, Wherein the organic light emitting display device comprises a plurality of organic light emitting display devices.
6. The method of claim 5,
The pixel electrode functions as a second capacitor electrode integrally formed with the light emitting portion and the transparent portion and serving as a pixel electrode in the light emitting portion and forming a capacitance with the first capacitor electrode in the transparent portion Wherein the organic electroluminescent display device is a display device.
6. The method of claim 5,
Wherein the step of forming the second gate electrode and the first capacitor electrode and the reflective film with the pixel electrode is performed by a diffraction exposure technique using a halftone mask.

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