KR102242982B1 - Organic light emitting diode device and method for fabricating the same - Google Patents

Abstract

The present invention relates to an organic light emitting display device and a method of manufacturing the same. An overcoat layer formed over the entire back plan substrate including the thin film transistor; An anode electrode formed on the overcoat layer and connected to the thin film transistor; A bus electrode formed on the overcoat layer and spaced apart from the anode electrode; A bank film formed on the overcoat layer between the anode electrode and the bus electrode; A light emitting layer formed on the anode electrode between the bank layers; And a cathode electrode formed on the back plan substrate and in electrical contact with the bus electrode.

Description

Organic light emitting display device and its manufacturing method {ORGANIC LIGHT EMITTING DIODE DEVICE AND METHOD FOR FABRICATING THE SAME}

The present invention relates to an organic light emitting device, and more particularly, an organic light emitting display capable of reducing the sheet resistance of a cathode electrode of a top emission type organic light emitting diode (OLED). It relates to an apparatus and a method of manufacturing the same.

As the information society develops, demands for display devices for displaying images are increasing in various forms, and in recent years, liquid crystal displays (LCDs), plasma display panels (PDPs), and organic light-emitting diodes have been developed. Various flat panel displays such as devices (OLED: organic light emitting diodes) are being used.

Among such display devices, the organic light-emitting device is a self-luminous device and does not require a backlight used in a liquid crystal display device that is a non-light-emitting device, and thus can be lightweight and thin.

In addition, the organic light emitting device has superior viewing angle and contrast ratio compared to the liquid crystal display device, and is advantageous in terms of power consumption. In addition, DC low voltage driving is possible, response speed is fast, and internal components are solid, so it is resistant to external shocks, has a wide operating temperature range, and has an advantage of being inexpensive, especially in terms of manufacturing cost.

Organic light-emitting display devices having the characteristics of such organic light-emitting devices are largely divided into a passive matrix type and an active matrix type, and the passive matrix type crosses signal lines and constructs the device in a matrix form. On the other hand, in the active matrix type, a thin film transistor, which is a switching element that turns on/off a pixel, a driving thin film transistor that passes current, and a capacitor that maintains voltage for one frame, is located for each pixel. Configure the device.

In recent years, the passive matrix type has many limiting factors such as resolution, power consumption, and lifespan, and thus active matrix type organic light emitting devices capable of realizing high resolution or large screen are actively being studied.

In addition, such an organic light emitting display device is divided into a top emission type and a bottom emission type according to a transmission direction of emitted light.

Among them, a conventional organic light emitting display device to which the top emission method is applied will be schematically described with reference to FIG. 1 as follows.

1 is a schematic cross-sectional view of a top emission type organic light emitting display device according to the prior art.

Referring to FIG. 1, an organic light emitting display device 10 according to the prior art includes a plurality of thin film transistors (TFTs (, organic light emitting device E) and a storage capacitor (not shown)).

The plurality of thin film transistors (TFT) is composed of a switching thin film transistor (not shown) and a driving thin film transistor (Td), these thin film transistors, for example, the driving thin film transistor (Td) is It is composed of a gate electrode 13, a gate insulating film 15, an active layer 17, a source electrode 21, and a drain electrode 23 on the entire surface.

A passivation layer 24 (ILD: inter layer dielectric) and an overcoat layer 25 are formed on the entire surface of the back plan substrate 11 to cover the driving thin film transistor Td.

A drain contact hole (not shown) exposing the drain electrode 23 is formed on the overcoat layer 25 by etching a portion of the overcoat layer 25 and the passivation layer 24, and through the drain contact hole An anode electrode 27 made of a transparent conductive material such as indium-tin-oxide (ITO) is formed in contact with the drain electrode 23.

A bank film 29 is formed on an upper surface of the overcoat layer 25 between the anode electrodes 27 to define a display area in which an image is displayed, that is, an opening.

A light emitting layer 31 that emits light by an applied current is formed on the anode electrode 27, and a transparent cathode electrode 33 is formed on the front surface of the back plan substrate 11 including the light emitting layer 31. In this case, the emission layer 31 includes a red emission layer 31R, a green emission layer 31G, and a blue emission layer 31B formed in each sub-pixel.

The anode electrode 27, the light emitting layer 31, and the cathode electrode 33 constitute an organic light emitting device (E), and light is emitted by supplying current to the organic light emitting device (E) by switching of the thin film transistor (Td). Then, an image is displayed by the organic light emitting elements E formed in a plurality of pixels.

Although not shown in the drawing, an encapsulation substrate (not shown) is formed on the front surface of the back plan substrate 11 including the cathode electrode 33 to seal the organic light emitting device E from external factors such as moisture.

As described above, in the conventional top emission type organic light emitting display device 10, since the transparent cathode electrode 33 is used, electrical conductivity is lowered and the surface resistance of the organic light emitting display device 10 increases. It is done.

Accordingly, when the surface resistance of the organic light emitting display device 10 increases, power consumption of the organic light emitting display device increases.

The present invention is to solve the above problems, and an object of the present invention is the surface resistance of a cathode electrode of a top emission type organic light emitting diode (OLED) and power consumption of the display device. It is to provide an organic electroluminescent display device capable of reducing the value and a method of manufacturing the same.

An organic light emitting display device according to the present invention for solving the above technical problem is an organic light emitting display device including a plurality of pixels, comprising: a back plan substrate in which a plurality of pixel regions and dummy regions are defined; A thin film transistor provided in a pixel area of the back plan substrate; An overcoat layer formed on the entire surface of a back plan substrate including the thin film transistor and exposing a portion of the thin film transistor; An anode electrode formed on the overcoat layer in the pixel region and connected to the thin film transistor; A bus electrode formed on the overcoat layer in the dummy region; A bank film formed on the overcoat layer between the anode electrode and the bus electrode; A light emitting layer formed on the anode electrode between the bank layers; A first cathode electrode formed on a back plan substrate including the light emitting layer and exposing the bus electrode; And a second cathode electrode formed on the first cathode electrode and in contact with the bus electrode.

An organic light emitting display device according to the present invention for solving the above technical problem is an organic light emitting display device including a plurality of pixels, comprising: a back plan substrate in which a plurality of pixel regions and dummy regions are defined; A thin film transistor provided in a pixel area of the back plan substrate; An overcoat layer formed on the entire surface of a back plan substrate including the thin film transistor and exposing a portion of the thin film transistor; An anode electrode formed on the overcoat layer in the pixel region and connected to the thin film transistor; A bus electrode formed on the overcoat layer in the dummy region; A bank film formed on the overcoat layer between the anode electrode and the bus electrode; A light emitting layer formed on the anode electrode between the bank layers; A first cathode electrode formed on a back plan substrate including the light emitting layer and having a via hole exposing the bus electrode; And a second cathode electrode formed on the first cathode electrode and in contact with the bus electrode through the via hole.

An organic light emitting display device according to the present invention for solving the above technical problem is an organic light emitting display device including a plurality of pixels, comprising: a back plan substrate in which a plurality of pixel regions and dummy regions are defined; A thin film transistor provided in a pixel area of the back plan substrate; An overcoat layer formed on the entire surface of a back plan substrate including the thin film transistor and exposing a portion of the thin film transistor; An anode electrode formed on the overcoat layer in the pixel region and connected to the thin film transistor; A bus electrode formed on the overcoat layer in the dummy region; A bank film formed on the overcoat layer between the anode electrode and the bus electrode; A hole injection layer, a hole transport layer, and an organic layer stacked on the anode electrode between the bank layers; An electron transport layer and an electron injection layer stacked on an entire surface of the back plan substrate including the organic layer, the bank layer, and the bus electrode; A first cathode electrode formed on a back plan substrate including the electron injection layer and having a via hole exposing the bus electrode through the electron injection layer and the electron transport layer; And a second cathode electrode formed on the first cathode electrode and in contact with the bus electrode through the via hole.

In an organic light emitting display device manufacturing method according to the present invention for solving the above technical problem, in a method of manufacturing an organic light emitting display device including a plurality of pixels, a back plan substrate in which a pixel region and a dummy region are defined is provided. The step of doing; Forming a thin film transistor on the back plan substrate in the pixel region; Forming an overcoat layer on the entire surface of a back plan substrate including the thin film transistor; Forming a drain contact hole exposing the drain electrode of the thin film transistor in the overcoat layer; Forming an anode electrode connected to the drain electrode on the overcoat layer in the pixel region and forming a bus electrode on the overcoat layer in the dummy region; Forming a bank film on the overcoat layer between the anode electrode and the bus electrode; Sequentially laminating a hole injection layer, a hole transport layer, and an organic material layer on an anode electrode between the bank layers; Sequentially laminating an electron transport layer and an electron injection layer on the entire surface of a back plan substrate including the organic material layer and the bank layer; Forming a first cathode electrode layer on an entire surface of a back plan substrate including the electron injection layer; Forming a via hole exposing the bus electrode to a first cathode electrode layer on the dummy region, an electron injection layer, an electron transport layer, and a bus electrode below the dummy region; And forming a second cathode electrode layer contacting the bus electrode through the via hole on a back plan substrate including the first cathode electrode layer.

An organic light emitting display device according to the present invention and a method of manufacturing the same include forming a bus electrode in a dummy region defined adjacent to a subpixel located at an outer side among a plurality of subpixels constituting a pixel, thereby forming a bus electrode and a cathode electrode. By making contact, the sheet resistance of the cathode electrode is reduced, so that power consumption of the display device can be reduced.

In addition, according to the present invention, since the sheet resistance of the cathode electrode is reduced due to electrical contact between the cathode electrode and the bus electrode, heat generation of the cathode electrode is reduced, thereby increasing the lifetime of the organic light emitting diode (OLED).

1 is a schematic cross-sectional view of a top emission type organic light emitting display device according to the prior art.
2 is a schematic circuit diagram of an organic light emitting display device according to the present invention.
3 is a schematic cross-sectional view of an organic light emitting display device according to the present invention.
4A to 4M are cross-sectional views illustrating a manufacturing process of an organic light emitting display device according to the present invention.

Hereinafter, an organic light emitting display device according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

In describing the embodiments of the present invention, when it is described that a structure is formed'on or above' and'below or below' other structures, such a substrate is not only a case in which the structures are in contact with each other, but also these structures. It should be interpreted as including the case where a third structure is interposed between them.

2 is a schematic circuit diagram of an organic light emitting display device according to the present invention.

Referring to FIG. 2, in the organic light emitting display device according to the present invention, a gate line (GL), a data line (DL), a power line (PL), a red sub-pixel area (R-PA), and a green sub-pixel area (G) -PA), a blue sub-pixel area (B-PA), and a bus electrode 117b.

The gate line GL is arranged to extend in a first direction on a substrate (not shown), and the data line DL is arranged to extend in a second direction by crossing the gate line GL on the substrate. The line PL is arranged in parallel with the data line DL while being spaced apart from the data line DL.

The plurality of gate lines GL and data lines DL are arranged crosswise to each other to define a red sub-pixel area R-PA, a green sub-pixel area G-PA, and a blue sub-pixel area B-PA. .

The thin film transistor includes a switching thin film transistor Ts and a driving thin film transistor Td. The switching thin film transistor Ts is connected to a gate line GL and a data line DL to receive a gate signal and a data signal.

One end of the switching thin film transistor Ts is connected to the driving thin film transistor Td, and the driving thin film transistor Td is connected to the power line PL and the organic light emitting diode E.

The bus electrode 117b is arranged in parallel with the data line DL to contact the cathode electrode (not shown, see 140 of FIG. 3) of the organic light emitting diode E.

3 is a schematic cross-sectional view of an organic light emitting display device according to the present invention.

Referring to FIG. 3, each of a plurality of pixels constituting the organic light emitting display device 100 according to the present invention includes an organic light emitting diode (OLED) (E) emitting light by a current applied according to an image signal, and A plurality of thin film transistors for supplying current to the light emitting diode E, that is, a switching thin film transistor Ts, a driving thin film transistor Td, and a storage capacitor (not shown; see Cst of FIG. 2).

In FIG. 3, switching thin film transistors among a plurality of thin film transistors are not shown, and description will be made on the assumption that only the driving thin film transistor TD for switching the current supplied to the organic light emitting diode E is shown.

The driving thin film transistor Td is on the back plan substrate 101 in which a plurality of red sub-pixel regions R-PA, green sub-pixel regions G-PA, and blue sub-pixel regions B-PA are defined. It comprises a gate electrode 103, a gate insulating film 105, an active layer 107, a source electrode 109a, and a drain electrode 109b to be stacked.

The back plan substrate 101 may be a transparent glass substrate or a flexible plastic substrate.

The gate electrode 103 is formed in each sub-pixel region of the back plan substrate 101 and is connected to a gate line (not shown, see GL in FIG. 2 ). The gate electrode 103 is in the group consisting of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu). It may be a multilayer made of any one selected or an alloy thereof.

The gate insulating film 105 is formed on the back plan substrate 101 including the gate electrode 103. The gate insulating layer 105 may be a silicon oxide layer (SiOx), a silicon nitride layer (SiNx), or multiple layers thereof, but is not limited thereto.

The active layer 107 is formed on the gate insulating layer 105 on the gate electrode 103 and may include amorphous silicon or polycrystalline silicon crystallized therefrom.

The source electrode 109a and the drain electrode 109b are formed on the active layer 107. The source electrode 109a and the drain electrode 109b may be formed of a single layer or multiple layers, and molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel ( Ni), neodymium (Nd) and copper (Cu) may be made of any one selected from the group consisting of, or an alloy thereof.

The protective layer 112 is formed on the back plan substrate 101 including the source electrode 109a and the drain electrode 109b. The protective layer 113 may be a silicon oxide layer (SiOx), a silicon nitride layer (SiNx), or multiple layers thereof, but is not limited thereto.

The overcoat layer 113 is formed on the protective layer 112 and may be a silicon oxide layer (SiOx), a silicon nitride layer (SiNx), or multiple layers thereof, but is not limited thereto. That is, the overcoat layer 113 may be formed of an organic insulating material such as photo-acryl or polyimide.

The anode electrode 117a is formed on the overcoat layer 113, and transparent Indium Tin Oxide (ITO) or Indium Zinc Oxide (IZO), ITO/Ag, ITO/Ag/ITO, ITO/Wox, etc. may be used. Not limited. The anode electrode 117a is electrically connected to the drain electrode 109b, and for this purpose, a drain contact hole 115 is formed in a predetermined region of the overcoat layer 113 and the protective layer 112 under it.

The bus electrode 117b is formed on the overcoat layer 113, and is transparent ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide), ITO/Ag, ITO/Ag/ which is the same material as the anode electrode 117a. ITO, ITO/Wox, etc. may be used, but are not limited thereto. The bus electrode 117b is formed to be spaced apart from the anode electrode 117a, and does not contact the anode electrode 117a, but is in contact with the cathode electrode 140, which will be described later. In addition, the bus electrode 117b is one of a red sub-pixel area (R-PA: Red Pixel Area), a green sub-pixel area (G-PA: Red Pixel Area), and a blue sub-pixel area (B-PA: Red Pixel Area). It is formed in a dummy area (DA) provided adjacent to a blue sub-pixel area (B-PA) located outside. Since the bus electrode 117b comes into contact with the second transparent conductive layer 133 of the cathode electrode 140, the surface resistance of the cathode electrode 140 decreases. In addition, due to the electrical contact between the second transparent conductive layer 133 of the cathode electrode 140 and the bus electrode 117b, the sheet resistance of the cathode electrode 133 is reduced. It is possible to increase the life of the electroluminescent device (OLED).

The bank film 119 is formed on the overcoat layer 113 between the anode electrodes 117b and may include an organic material such as a benzocyclobutene (BCB) resin, an acrylic resin, or a polyimide resin. The bank film 117b is formed to have a predetermined opening on the anode electrode 117a so that light generated from the light emitting layer 121 can escape.

The light-emitting layer 121 is formed on the bank layer 119 and includes a red light-emitting layer (not shown), a green light-emitting layer (not shown), and a blue light-emitting layer (not shown), although not shown in the drawing. Each of these red, green, and blue light-emitting layers is formed for each of the red sub-pixel area (R-PA), the green sub-pixel area (G-PA), and the blue sub-pixel area (B-PA).

Although not shown in the drawing, the emission layer 121 is a hole injection layer (HIL) 121a, a hole transport layer (HTL) 121b, and an emission layer (EL) 121c. , An electron transport layer (ETL) 121d and an electron injection layer (EIL) 121e.

The cathode electrode 140 is formed on the front side of the back plan substrate 101 including the light emitting layer 121, and uses a metal material such as _{magnesium (Mg), aluminum (Al), calcium (Ca), WO 3} and MnO _3. Alternatively, a transparent material such as Indium Tin Oxide (ITO) or Indium Zinc Oxide (IZO) may be used. The cathode electrode 140 has a stacked structure of the first transparent conductive layer 123 and the second transparent conductive layer 133 and is in electrical contact with the bus electrode 117b. As the cathode electrode 140 comes into contact with the bus electrode 117b, the surface resistance of the cathode electrode 140 decreases.

The encapsulation substrate 135 is formed on the entire surface of the back plan substrate 101 including the cathode electrode 133, and encapsulates the organic light emitting diode E from external factors such as moisture.

Therefore, when a driving voltage is applied to the anode electrode 117a and the cathode electrode 140, holes passing through the hole transport layer 121b and electrons passing through the electron transport layer 121d are moved to the organic layer 121c to form excitons. As a result, the light emitting layer 121 emits visible light.

As described above, in the organic light emitting display device according to the present invention, a bus electrode is formed in a dummy region defined adjacent to a subpixel located at an outer side among a plurality of subpixels constituting a pixel to be electrically connected to the cathode electrode. By making contact, the sheet resistance of the cathode electrode is reduced, thereby reducing power consumption of the display device.

In addition, according to the present invention, due to electrical contact between the second transparent conductive layer of the cathode electrode and the bus electrode, the sheet resistance of the cathode electrode is reduced, so that heat generation of the cathode electrode is reduced, thereby increasing the lifespan of the organic light-emitting device (OLED). have.

Meanwhile, a method of manufacturing an organic light emitting display device according to the present invention having the above configuration will be described with reference to FIGS. 4A to 4M as follows.

4A to 4M are cross-sectional views illustrating a manufacturing process of an organic light emitting display device according to the present invention.

In FIGS. 4A to 4M, switching thin film transistors among a plurality of thin film transistors are not shown, and description will be made on the assumption that only the driving thin film transistor TD for switching the current supplied to the organic light emitting diode E is shown.

As shown in FIG. 4A, first, a back plan substrate in which a red sub-pixel area (R-PA), a green sub-pixel area (G-PA), a blue sub-pixel area (B-PA), and a dummy area DA are defined. Prepare 101. The back plan substrate 101 may be a glass substrate made of a transparent material or a flexible plastic substrate.

Thereafter, a first metal material is deposited on the back plan substrate 101 and patterned to form a gate electrode 103 in each sub-pixel area of the back plan substrate 101. The gate electrode 103 is connected to a gate line (not shown, see GL in FIG. 2 ). The first metal material for the gate electrode 103 is molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu ) It may be a multilayer made of any one selected from the group consisting of or an alloy thereof.

Subsequently, as shown in FIG. 4B, a gate insulating film 105 is formed on the back plan substrate 101 including the gate electrode 103. The gate insulating layer 105 may be a silicon oxide layer (SiOx), a silicon nitride layer (SiNx), or multiple layers thereof, but is not limited thereto.

Thereafter, a semiconductor layer (not shown) is formed on the gate insulating layer 105 and then patterned to form an active layer 107 on the gate insulating layer 105 on the gate electrode 103. The semiconductor layer may include amorphous silicon or polycrystalline silicon obtained by crystallizing the same.

Subsequently, as shown in FIG. 4C, after depositing a second metal material on the gate insulating layer 105 including the active layer 107 and patterning the second metal material, source electrodes spaced apart from each other on the active layer 107 ( 109a) and a drain electrode 109b are formed. The source electrode 109a and the drain electrode 109b may be formed of a single layer or multiple layers. The second metal material is from the group consisting of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu). It may be made of any one selected or an alloy thereof.

The gate electrode 103, the gate insulating film 105, the active layer 107, the source electrode 109a, and the drain electrode 109b constitute a driving thin film transistor Td, and the driving thin film transistor Td is It is formed in a plurality of red sub-pixel areas R-PA, green sub-pixel areas G-PA, and blue sub-pixel areas B-PA.

Then, as shown in FIG. 4D, a protective layer 112 and an overcoat layer 113 are sequentially formed on the back plan substrate 101 including the source electrode 109a and the drain electrode 109b. The protective layer 112 and the overcoat layer 113 may be a silicon oxide layer (SiOx), a silicon nitride layer (SiNx), or multiple layers thereof, but are not limited thereto.

Subsequently, partial regions of the overcoat layer 113 and the passivation layer 112 are etched to form a drain contact hole 115 exposing the drain electrode 109b of each sub-pixel region.

Then, as shown in FIG. 4D, a transparent conductive material layer 117 is deposited on the overcoat layer 113 including the drain contact hole 115. In this case, the transparent ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide), ITO/Ag, ITO/Ag/ITO, ITO/Wox, etc. may be used, but the present invention is not limited thereto.

Subsequently, as shown in FIG. 4E, the transparent conductive material layer 117 is selectively patterned to form the red sub-pixel area R-PA, the green sub-pixel area G-PA, and the blue sub-pixel area B. A bus electrode 117b is simultaneously formed in the dummy region DA together with the anode electrode 117a connected to the drain electrode 109b in -PA). In this case, the bus electrode 117b is separated from the anode electrode 117a without being in electrical contact. In addition, the bus electrode 117b is in a dummy area DA that occupies a smaller area than the red sub-pixel area (R-PA), the green sub-pixel area (G-PA), and the blue sub-pixel area (B-PA). Formed, and has little effect on the aperture ratio of the display device. In addition, since the bus electrode 117b is also formed when the anode electrode 117a is formed, a separate additional process for forming the bus electrode 117b is not required, thereby simplifying the manufacturing process.

Then, as shown in FIG. 4F, a bank film 119 is formed on the overcoat layer 113 between the anode electrode 117a and the bus electrode 117b. The bank film 119 may include an organic material such as a benzocyclobutene (BCB) resin, an acrylic resin, or a polyimide resin. The bank layer 117b is formed to be spaced apart from a display area on the anode electrode 117a in which an image is displayed, that is, a predetermined opening so that light generated from the organic light emitting layer 121 to be described later can escape.

Subsequently, inkjet printing a first liquid material for a hole injection layer (HIL) and a second liquid material for a hole transport layer (HTL) on the anode electrode 117a between the bank films 119 A hole injection layer (HIL) 121a and a hole transport layer (HTL) 121b are sequentially formed by sequentially discharging and drying using a method.

Then, as shown in FIG. 4G, a light-emitting liquid material, for example, red, green, and blue light-emitting liquid material, is discharged and dried using an inkjet printing method on the hole transport layer 121b to form an organic layer 121c. To form. Although not shown in the drawing, the organic layer 121c includes a red organic layer, a green organic layer, and a blue organic layer. Each of these red, green, and blue organic layers is formed in each of the red subpixel area R-PA, the green subpixel area G-PA, and the blue subpixel area B-PA.

Subsequently, as shown in FIG. 4H, an electron injection layer (EIL) and an electron transport layer (ETL) on the front of the back plan substrate 101 including the organic layer 121c and the bank layer 119 ) Solution material is sequentially deposited to sequentially form an electron transport layer 121d and an electron injection layer 121e. In this case, the electron transport layer 121d and the electron injection layer 121e are formed on the entire surface of the bus electrode 117b as well as the organic layer 121c and the bank layer 119. The hole injection layer (HIL) (121a), the hole transport layer (HTL) (121b), the organic layer (121c), the electron transport layer (121d) and the electron injection layer (121e) is a light emitting layer (121) To achieve.

Then, as shown in FIG. 4I, a first transparent conductive layer 123 is deposited on the entire surface of the back plan substrate 101 including the electron injection layer 121e. At this time, the first transparent conductive layer 123 may be formed of a metal material such as magnesium (Mg), aluminum (Al), calcium (Ca), WO ₃ , MnO ₃ , Indium Tin Oxide (ITO) or IZO ( Transparent materials such as Indium Zinc Oxide) can also be used. The first transparent conductive layer 123 does not come into contact with the bus electrode 117b formed in the dummy area DA because of the electron transport layer 121d and the electron injection layer 121e.

Subsequently, as shown in Figs. 4j and 4k, a punching process is performed using a punching tool 125 to form the first transparent conductive layer 123 on the upper portion of the bus electrode 117b and the electron transport layer thereunder. (121c), the electron injection layer 121d, and the bus electrode 117b are sequentially punched to form a via hole 131 exposing the surface of the bus electrode 117b. At this time, since the anode electrode 117a has an overcoat layer 113 on its lower surface, it has a degree of freedom with respect to the punching depth. In this case, when the via hole 131 is formed, the via hole can be easily formed through a punching process without an etching process using a separate mask, thereby simplifying the manufacturing process.

Next, as shown in FIG. 4L, a second transparent conductive layer 133 is deposited on the first transparent conductive layer 123 on which the via hole 131 is formed, and the bus electrode ( 117b). The second transparent conductive film 133 may be formed of a metal material such as magnesium (Mg), aluminum (Al), calcium (Ca), WO ₃ , MnO _{3, and ITO} A transparent material such as (Indium Tin Oxide) or IZO (Indium Zinc Oxide) may be used. In this case, the stacked first transparent conductive film 123 and second transparent conductive film 133 form a cathode electrode 140.

In this way, the surface resistance of the cathode electrode 140 is reduced by bringing the second transparent conductive layer 133 constituting the cathode electrode 140 into contact with the bus electrode 117b through the via hole 131. In addition, due to the electrical contact between the second transparent conductive layer 133 of the cathode electrode 140 and the bus electrode 117b, the sheet resistance of the cathode electrode 133 is reduced. It is possible to increase the life of the electroluminescent device (OLED).

In this way, when the driving voltage is applied to the anode electrode 117a and the cathode electrode 140, holes passing through the hole transport layer 121b and electrons passing through the electron transport layer 121d are moved to the organic layer 121c to form excitons. As a result, the light emitting layer 121 emits visible light.

Subsequently, as shown in FIG. 4M, the organic light-emitting diode E is encapsulated on the entire surface of the back plan substrate 101 including the second transparent conductive film 133 constituting the cathode electrode 140 from external factors such as moisture. In order to do so, by forming the encapsulation substrate 135, the manufacturing process of the organic light emitting display device 100 according to the present invention is completed.

As described above, in the method of manufacturing an organic light emitting display device according to the present invention, a bus electrode is formed in a dummy area defined adjacent to a subpixel located at an outer side among a plurality of subpixels constituting a pixel, thereby forming a bus electrode and a cathode electrode. By making electrical contact, the sheet resistance of the cathode electrode can be reduced, and thus, power consumption of the display device can be reduced.

In addition, according to the present invention, due to electrical contact between the second transparent conductive layer of the cathode electrode and the bus electrode, the sheet resistance of the cathode electrode is reduced, so that heat generation of the cathode electrode is reduced, thereby increasing the lifespan of the organic light-emitting device (OLED). have.

Those skilled in the art to which the present invention pertains will be able to understand that the above-described present invention can be implemented in other specific forms without changing the technical matters or essential features thereof. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not limiting.

The scope of the present invention is indicated by the claims to be described later rather than the detailed description, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention. do.

100: organic light emitting display device 101: back plan substrate
DESCRIPTION OF SYMBOLS 103 Gate electrode 105 Gate insulating film 107 Active layer 109a Source electrode 109b Drain electrode 112 Protective film
113: overcoat layer 115: drain contact hole 117a: anode electrode 117b: bus electrode 119: bank film 121a: hole injection layer
121b: hole transport layer 121c: organic layer
121d: electron transport layer 121e: electron injection layer
121: light emitting layer 123: first transparent conductive film
125: punching tool 131: via hole
133: second transparent conductive film 135: encapsulation substrate
140: cathode electrode

Claims (10)

In the organic light emitting display device including a plurality of pixels,
A back plan substrate in which a plurality of pixel areas and dummy areas are defined;
A thin film transistor provided in a pixel area of the back plan substrate;
An overcoat layer formed on the entire surface of a back plan substrate including the thin film transistor and exposing a portion of the thin film transistor;
An anode electrode formed on the overcoat layer in the pixel region and connected to the thin film transistor;
A bus electrode formed on the overcoat layer in the dummy region;
A bank film formed on the overcoat layer between the anode electrode and the bus electrode;
A light emitting layer formed on the anode electrode between the bank layers;
A first cathode electrode formed on a back plan substrate including the light emitting layer and exposing the bus electrode; And
And a second cathode electrode formed on the first cathode electrode and in contact with the bus electrode,
An electron transport layer and an electron injection layer are sequentially formed on the bus electrode, and the first cathode electrode is formed on the electron injection layer,
Via holes are formed in the first cathode electrode, the electron injection layer, the electron transport layer, and the bus electrode,
The second cathode electrode is in electrical contact with the bus electrode through the via hole. The organic light emitting display device of claim 1, wherein the bus electrode is made of the same material as the anode electrode. In the organic light emitting display device including a plurality of pixels,
A back plan substrate in which a plurality of pixel areas and dummy areas are defined;
A thin film transistor provided in a pixel area of the back plan substrate;
An overcoat layer formed on the entire surface of a back plan substrate including the thin film transistor and exposing a portion of the thin film transistor;
An anode electrode formed on the overcoat layer in the pixel region and connected to the thin film transistor;
A bus electrode formed on the overcoat layer in the dummy region;
A bank film formed on the overcoat layer between the anode electrode and the bus electrode;
A light emitting layer formed on the anode electrode between the bank layers;
A first cathode electrode formed on a back plan substrate including the light emitting layer and having a via hole exposing the bus electrode; And
And a second cathode electrode formed on the first cathode electrode and in contact with the bus electrode through the via hole,
An electron transport layer and an electron injection layer are sequentially formed on the bus electrode, and the first cathode electrode is formed on the electron injection layer,
An organic light emitting display device in which the via hole is formed in the first cathode electrode, the electron injection layer, the electron transport layer, and the bus electrode. The organic light emitting display device of claim 3, wherein the bus electrode is made of the same material as the anode electrode. In the organic light emitting display device including a plurality of pixels,
A back plan substrate in which a plurality of pixel areas and dummy areas are defined;
A thin film transistor provided in a pixel area of the back plan substrate;
An overcoat layer formed on the entire surface of a back plan substrate including the thin film transistor and exposing a portion of the thin film transistor;
An anode electrode formed on the overcoat layer in the pixel region and connected to the thin film transistor;
A bus electrode formed on the overcoat layer in the dummy region;
A bank film formed on the overcoat layer between the anode electrode and the bus electrode;
A hole injection layer, a hole transport layer, and an organic layer stacked on the anode electrode between the bank layers;
An electron transport layer and an electron injection layer stacked on an entire surface of the back plan substrate including the organic layer, the bank layer, and the bus electrode;
A first cathode electrode formed on a back plan substrate including the electron injection layer and having a via hole exposing the bus electrode through the electron injection layer and the electron transport layer; And
And a second cathode electrode formed on the first cathode electrode and in contact with the bus electrode through the via hole,
The electron transport layer and the electron injection layer are sequentially formed on the bus electrode, and the first cathode electrode is formed on the electron injection layer,
An organic light emitting display device in which the via hole is formed in the first cathode electrode, the electron injection layer, the electron transport layer, and the bus electrode. The organic light emitting display device of claim 5, wherein the bus electrode is made of the same material as the anode electrode. delete In the method of manufacturing an organic light emitting display device including a plurality of pixels,
Providing a back plan substrate in which pixel regions and dummy regions are defined;
Forming a thin film transistor on the back plan substrate in the pixel region;
Forming an overcoat layer on the entire surface of a back plan substrate including the thin film transistor;
Forming a drain contact hole exposing the drain electrode of the thin film transistor in the overcoat layer;
Forming an anode electrode connected to the drain electrode on the overcoat layer in the pixel region and forming a bus electrode on the overcoat layer in the dummy region;
Forming a bank film on the overcoat layer between the anode electrode and the bus electrode;
Sequentially laminating a hole injection layer, a hole transport layer, and an organic material layer on an anode electrode between the bank layers;
Sequentially laminating an electron transport layer and an electron injection layer on the entire surface of a back plan substrate including the organic material layer and the bank layer;
Forming a first cathode electrode layer on an entire surface of a back plan substrate including the electron injection layer;
Forming a via hole exposing the bus electrode in a first cathode electrode layer on the dummy region, an electron injection layer, an electron transport layer, and a bus electrode below the dummy region; And
And forming a second cathode electrode layer on the back plan substrate including the first cathode electrode layer, which is in contact with the bus electrode through the via hole, and
A method of manufacturing an organic light emitting display device in which the via hole is formed in the first cathode electrode above the dummy region, the electron injection layer below the electron injection layer, the electron transport layer, and the bus electrode by a punching process using a punching tool. 9. The method of claim 8, wherein the bus electrode is made of the same material as the anode electrode. delete

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