KR100739068B1 - An organic light emitting display and fabrication method thereof - Google Patents

Abstract

An organic light emitting display and a manufacturing method thereof are provided to prevent a short between an anode electrode and a cathode electrode due to particles by removing the particles. An organic light-emitting display includes a lower structure, an organic light emitting device, and a pixel defined film(28). The lower structure is formed on a substrate. The organic light emitting device is formed on the lower structure. The pixel defined film(28) is formed at a space between the organic light emitting devices. The organic light emitting device includes a first electrode(22), an organic light emitting layer(24), and a second electrode(26). The first electrode(22) includes a metal layer formed on the lower structure, and a transparent conductive film of more than two layers formed on the metal layer. The organic light emitting layer(24) is formed on the first electrode(22). The second electrode(26) is formed on the organic light emitting layer(24), and transmits light generated at the organic light emitting layer(24).

Description

Organic light-emitting display device and method for manufacturing same {AN ORGANIC LIGHT EMITTING DISPLAY AND FABRICATION METHOD THEREOF}

1 is a cross-sectional view illustrating a schematic configuration of a top-emitting organic light emitting diode display according to an exemplary embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a structure in a state where the anode electrode of FIG. 1 is formed. FIG.

3 is a process block diagram illustrating a method of manufacturing a top-emitting organic light emitting display device according to an exemplary embodiment of the present invention.

4 is a conceptual diagram illustrating a method of performing a first process using the electric shock of FIG. 3.

5A to 5C are waveform diagrams illustrating various waveforms of a power supply used in the first process of FIGS. 3 and 4.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting display device and a method for manufacturing the same, and more particularly, to an organic light emitting display device including an anode electrode having a triple layer structure of Ag / ITO / ITO, and a manufacturing method for effectively manufacturing the device. It is about.

Recently, various flat panel displays have been developed to reduce weight and volume, which are disadvantages of cathode ray tubes. Such flat panel displays include Liquid Crystal Display (LCD), Field Emission Display (FED), Plasma Display Panel (PDP) and Organic Light Emitting Display (PDP). Etc.

The organic light emitting diode display is a self-luminous display device that electrically excites an organic compound to emit light. The organic light emitting diode display may display an image by voltage driving or current driving N × M organic light emitting devices.

Since the organic light emitting diode has diode characteristics, it is also called an organic light emitting diode, and includes an anode electrode as a hole injection electrode, an organic thin film as a light emitting layer, and a cathode electrode as an electron injection electrode. When the exciton, which is a combination of holes and electrons injected into the thin film, falls from the excited state to the ground state, light is emitted.

The organic light emitting diode display may be classified into a top emission type, a bottom emission type, and a double emission type according to a light emission type.

Here, the top emission type refers to the manner in which the light of the light emitting layer is transmitted through the cathode electrode and the encap member provided on the upper side of the layer, and the bottom emission type refers to the anode electrode and the substrate provided with the light of the light emitting layer below the layer. The light-emitting layer refers to a method in which light of the light emitting layer is transmitted through both sides of the encap member and the substrate.

Accordingly, in the above-mentioned top emission type organic light emitting diode display, the anode electrode is formed in a multiple structure using a transparent conductive film and a metal film to reflect the light of the light emitting layer toward the cathode electrode.

As an example of the anode electrode described above, an anode electrode having a triple film structure of ITO / Ag / ITO is disclosed.

However, the above-described anode electrode of the conventional structure has particles generated during the formation of the anode electrode in the deposition chamber, in particular particles generated when the metal film (Ag) is deposited on the ITO of the uppermost layer so that the anode electrode and the cathode electrode Short is generated in the liver, resulting in particle dark spots resulting in a decrease in yield.

In order to solve this problem, conventionally, the particles generated inside the deposition chamber are sucked out and discharged to the outside of the chamber, and the particles attached to the surface of the anode electrode are removed by a cleaning operation using a cleaner. In the conventional anode electrode structure, the above cleaning operation alone does not effectively remove particles.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to provide an organic light emitting display having an anode in which particle dark spots are eliminated.

Another object of the present invention is to provide a method of manufacturing an organic light emitting display device capable of effectively removing particles generated in an anode electrode deposition process.

In order to achieve the above object, the present invention provides an organic light emitting device formed on a lower structure on a substrate, the first electrode comprising a metal film and at least two or more transparent conductive films formed on the metal film, on the first electrode An organic light emitting display device includes: an organic light emitting layer formed on the organic light emitting layer; and a second electrode formed on the organic light emitting layer and transmitting light generated from the organic light emitting layer.

According to a preferred embodiment of the present invention, the transparent conductive film may be composed of a first transparent conductive film on a metal film and a second transparent conductive film on the first transparent conductive film.

The first transparent conductive film and the second transparent conductive film may be made of ITO, and the metal film may be made of Ag.

The first electrode and the second electrode may be formed of an anode electrode and a cathode electrode, respectively, and the lower structure may include a thin film transistor for driving the organic light emitting diode and a planarization film covering the thin film transistor.

In the organic light emitting diode display having the above configuration, forming a metal film on a lower structure provided on a substrate, forming a first transparent conductive film on the metal film, and performing a first grinding process to form particles on the first transparent conductive film. Grinding, performing a first cleaning process to remove particles on the first transparent conductive film, forming a second transparent conductive film on the first transparent conductive film, and performing a second grinding process to perform the second grinding process. According to the method of manufacturing an organic light emitting display device, a first electrode may be manufactured by pulverizing particles on a transparent conductive film, and removing particles on the second transparent conductive film by performing a second cleaning process.

Here, in the first and second grinding processes, an alternating voltage of 20 to 30 volts may be applied to the edges of the substrate, and pure or megasonic may be used in the first and second cleaning processes.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

1 is a cross-sectional view illustrating a schematic configuration of an organic light emitting diode display according to an exemplary embodiment of the present invention. In particular, FIG. 1 is a cross-sectional view of an active organic light emitting diode display having a top emission type, and FIG. It is sectional drawing which shows a structure.

3 is a process block diagram illustrating a method of manufacturing an organic light emitting display device according to an exemplary embodiment of the present invention. FIG. 4 is a conceptual diagram illustrating a method of performing the first and second grinding processes of FIG. 3. 5C is a waveform diagram illustrating various waveforms of power sources used in the first and second grinding processes of FIG. 4.

An organic light emitting diode display according to an exemplary embodiment of the present invention includes a substrate 30 on which a plurality of thin film transistors 10 and organic light emitting diodes 20 are provided in a display area, and a substrate by a sealant to seal the display area. It includes an encap glass 40 sealed to 30.

Here, the substrate 30 may be a glass substrate of a transparent material, a resin material of a opaque material or a metal substrate.

A buffer layer 32 is provided on the substrate 30, a thin film transistor 10 is provided in a portion of the buffer layer 32, and an organic light emitting device 20 is formed on the thin film transistor 10. Is placed.

Hereinafter, configurations of the thin film transistor 10 and the organic light emitting diode 20 will be described in more detail.

The semiconductor layer 10a is provided on the buffer film 32, and the gate insulating film 10b is provided on the semiconductor layer 10a and the buffer film 32.

A gate electrode 10c is provided on the gate insulating film 10b, an interlayer insulating film 10d is provided on the gate electrode 10c and the gate insulating film 10b, and a source / drain electrode 10e is provided on the interlayer insulating film 10d. Is provided. In this case, the source / drain electrode 10e is electrically connected to the semiconductor layer 10a through a connection hole of the interlayer insulating layer 10d.

A planarization film 10f is provided on the source / drain electrode 10e and the interlayer insulating film 10d, and an anode electrode 22 as a first electrode is provided on the planarization film 10f, and the anode electrode 22 is provided. Is electrically connected to the source / drain electrode 10e through a connection hole of the planarization film 10f.

The anode electrode 22 includes a metal film formed on the planarization film 10f and at least two or more transparent conductive films formed on the metal film.

FIG. 2 illustrates an anode 22 formed of a triple layer structure of the metal film 22a / first transparent conductive film 22b / second transparent conductive film 22c as an example of the anode electrode 22.

The metal layer 22a may be formed of Ag, and the first and second transparent conductive layers 22b and 22c may be formed of ITO.

As such, disposing two or more layers of the transparent conductive film on the metal film Ag effectively removes the particles P generated when the metal film 22a is deposited and deposited on the transparent conductive film. According to the structure of the anode electrode 22, the particle crushing and removal process can be performed first after the formation of the first transparent conductive film 22b, and secondly after the formation of the second transparent conductive film 22c.

Therefore, particle dark spots due to particles P on the transparent conductive film can be minimized.

A pixel defining layer 28 exposing the anode electrode 22 is formed on the planarization film 10f. An organic light emitting layer 24 and a cathode electrode as a second electrode are formed on the exposed anode electrode 22. 26 is formed sequentially.

Here, the cathode electrode 26 may be formed of a transparent conductive material, for example, ITO, to transmit the light emitted from the organic light emitting layer 24.

The organic light emitting layer 24 is configured to display any one of red (R), green (G), and blue (B), and includes a hole injection layer, a hole transport layer, It may have a multi-layer structure including an electron transport layer.

Although not shown, an electron injection layer (EIL) may be further formed between the electron transport layer and the cathode electrode 26.

In addition, the positions of the anode electrode 22 and the cathode electrode 26 may be interchanged. In this case, the cathode electrode can be formed in the same structure as the anode electrode of the above-described structure.

Hereinafter, a method of manufacturing the organic light emitting display device having the above configuration will be described.

First, the lower structure A is formed on the substrate 30. Although the lower structure A may be displayed in various forms according to the driving method and the light emitting method of the device, since the active light emitting display of the top emission type is described as an example, the present embodiment is described. The lower structure A in E includes a planarization film 10f and components provided under the film 10f.

After the lower structure A is formed, the electrode forming material Ag is deposited on the planarization film 10f in the deposition chamber to form the metal film 22a.

Subsequently, an electrode forming material (ITO) different from the metal film 22a is deposited on the metal film 22a to form the first transparent conductive film 22b.

In this case, particles generated when the metal film 22a is deposited are deposited on the first transparent conductive film 22b.

Therefore, after the first transparent conductive film 22b is formed, a process for removing the particles is performed.

More specifically, after the first transparent conductive film 22b is formed, a first grinding process is performed.

The first crushing process is a process using an electric shock, and as shown in FIG. 4, a voltage of 20 to 30 volts is applied to four corners of the substrate 30. When the voltage is applied, various waveforms shown in FIGS. 5A to 5C may be used.

When the above-mentioned first grinding process is carried out, particles adhering on the first transparent conductive film 22b are separated from the surface of the film 22b or are ground to a small size.

Thereafter, the first cleaning process is performed using pure water cleaning or megasonic cleaning to remove particles separated from the surface of the first transparent conductive film 22b or ground to a small size.

After the above-described first cleaning step, the second transparent conductive film 22c is formed on the first transparent conductive film 22b. The second transparent conductive film 22c may be formed of ITO similarly to the first transparent conductive film 22b.

Thereafter, the second grinding step is performed in the same manner as the first grinding step, and the particles P on the second transparent conductive film 22c are pulverized, and the second cleaning step is performed in the same manner as the first cleaning step. Remove the pulverized particle (P).

According to this method, the particles can be more easily removed by reducing the size and number of clusters generated during particle crushing.

When the second cleaning process is completed, the upper structure B is formed on the planarization film 10f. Here, the upper structure B may include a pixel defining layer 28, a light emitting layer 24, and a cathode electrode 26.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the scope of the invention.

According to the embodiment of the present invention described above, by effectively removing the particles that act as the main cause of dark spots, it is possible to prevent the short between the anode electrode and the cathode electrode caused by the particles.

Therefore, since the occurrence of particle dark spots can be minimized, there is an effect that can improve the yield.

Claims (14)

A lower structure provided on the substrate; An organic light emitting device formed on the lower structure; And Pixel defining layer formed in the space between the organic light emitting device To include, the organic light emitting device, A first electrode including a metal film formed on the lower structure and at least two or more transparent conductive films formed on the metal film; An organic emission layer formed on the first electrode; And A second electrode formed on the organic emission layer and transmitting light generated from the organic emission layer; An organic light emitting display comprising a. The method of claim 1, And the transparent conductive film comprises a first transparent conductive film on the metal film and a second transparent conductive film on the first transparent conductive film. The method of claim 2, An organic light emitting display device in which the first transparent conductive film and the second transparent conductive film are made of ITO. The method according to any one of claims 1 to 3, An organic light emitting display device in which the metal film is made of Ag. The method of claim 4, wherein And the first electrode is an anode electrode, and the second electrode is a cathode electrode. The method of claim 5, The lower structure includes a thin film transistor for driving the organic light emitting element, and a planarization layer covering the thin film transistor. A lower structure provided on the substrate; An anode electrode formed on the lower structure and having a triple layer structure of Ag / ITO / ITO; A pixel defining layer exposing the anode electrode; An organic emission layer formed on the anode; And A cathode formed on the organic emission layer and transmitting light generated from the organic emission layer An organic light emitting display comprising a. Forming a substructure on the surface of the substrate; Forming a first electrode on the lower structure; And Forming an upper structure on the first electrode Including, wherein forming the first electrode, Forming a metal film on the lower structure; Forming a first transparent conductive film on the metal film; Performing a first grinding process to grind particles on the first transparent conductive film; Performing a first cleaning process to remove particles on the first transparent conductive film; Forming a second transparent conductive film on the first transparent conductive film; Grinding a particle on the second transparent conductive film by performing a second grinding process; And Performing a second cleaning process to remove particles on the second transparent conductive film Method of manufacturing an organic light emitting display device comprising a. The method of claim 8, A method of manufacturing an organic light emitting display device in which the alternating voltage of 20 to 30 volts is applied to the edge of the substrate in the first and second grinding processes. The method of claim 9, A method of manufacturing an organic light emitting display device using pure water or megasonic in the first and second cleaning processes. The method according to any one of claims 8 to 10, The metal layer is formed of Ag. The method of claim 11, The first transparent conductive film and the second transparent conductive film is formed of ITO manufacturing method of an organic light emitting display device. The method of claim 12, And forming a planarization film covering the thin film transistor after forming the thin film transistor on the substrate in the forming of the lower structure. The method of claim 13, The forming of the upper structure may include forming a pixel defining layer exposing the first electrode and then laminating an organic emission layer and a second electrode on the first electrode.

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