WO2012113177A1

WO2012113177A1 - Organic light emitting diode sealed with thin film and preparation method thereof

Info

Publication number: WO2012113177A1
Application number: PCT/CN2011/073515
Authority: WO
Inventors: 狄国庆
Original assignee: 苏州大学
Priority date: 2011-02-25
Filing date: 2011-04-29
Publication date: 2012-08-30
Also published as: CN102651453B; CN102651453A; JP2014509050A

Abstract

An organic light emitting diode (OLED) sealed with a thin film and a preparation method thereof. The OLED comprises: a substrate (101); a transparent electrode layer (102), an organic light emitting material layer (103) and a metal cathode layer (104) which are formed on the surface of the substrate (101) in sequence; and a seal layer (105) formed on the metal cathode layer (104). The seal layer (105) is a tantalic oxide film (Ta₂O₅). The method for preparing the OLED comprises: providing the substrate (101); forming the transparent electrode layer (102), the organic light emitting material layer (103) and the metal cathode layer (104) on the surface of the substrate (101) in sequence; and forming the Ta₂O₅ layer on the surface of the metal cathode layer (104). By forming the Ta₂O₅ layer with a planar surface and high geometrical and optical density on the metal cathode layer of OLED, organic materials inside the OLED are sealed and isolated from vapor or oxygen. The OLED with good sealing and isolation effects and long working life is provide with simple procedure.

Description

The invention relates to a Chinese patent which is submitted to the Chinese Patent Office on February 25, 2011, and whose application number is 201110046398.9, and whose invention name is "film-sealed organic light-emitting diode and its manufacturing method" Priority of the application, the entire contents of which are incorporated herein by reference. Technical field

The present invention relates to the field of display and illumination technologies, and in particular, to an organic light emitting diode (OLED) using a film seal and a method of fabricating the same.

Background technique

Compared with other lighting and display products, OLED (Organic Light-Emitting Diode) has the advantages of ultra-thin, shock resistance, wide viewing angle, wide operating temperature, high contrast and flexible display. Potential advantages such as high efficiency and low cost are recognized as ideal display and lighting products. With the continuous improvement of OLED technology, the working life of OLED products has also been greatly improved, making it gradually enter commercial applications in the field of display and lighting, especially in displays, electronic billboards, mobile phones and GPS devices. usage of. OLED technology has become an important research and development direction in the field of display and lighting technology.

The basic structure of the OLED device comprises two opposite electrode layers and an organic light-emitting material layer disposed between the two electrode layers, wherein one electrode layer is an anode, that is, a transparent electrode layer (usually an indium tin oxide film, ITO), The electrode layer is disposed on the substrate, and the other electrode layer is a cathode metal layer (such as an aluminum film layer); the organic light-emitting material layer is divided into two types. If the small-molecule OLED is used, the organic light-emitting material layer has a layered structure, that is, The hole transport layer, the light-emitting layer and the electron transport layer are composed. If the polymer OLED is used, the organic light-emitting material layer has a single-layer structure. When the OLED device obtains an appropriate power supply, holes and electrons are injected from the anode and the cathode into the organic light-emitting material layer, respectively, and radiation recombination occurs, and the outer layer of the organic light-emitting material layer absorbs the energy released by the carrier recombination. Excited state, radiation transition to achieve luminescence.

Although OLED technology is one of the most ideal display and illumination technologies, the current stage of OLED There are still many technical problems to be solved in technology, especially the working life of OLED products, which restricts the production and popularization of OLED products to a large extent. In order to improve the working life of OLED products, an effective solution is to improve the packaging materials and technology of OLED products, because the organic materials of the organic luminescent material layer are very sensitive to water vapor and oxygen, even a very small amount of water vapor or oxygen corrosion will cause It exhibits extremely poor photochemical and electrochemical stability, while the active cathode metal layer also reacts with oxygen, greatly reducing the working life of OLED products. At present, commonly used packaging techniques include: using a UV-curable epoxy curing agent as a binder, bonding a glass or plastic cover as a cover material to a cathode metal layer for packaging, and adding a desiccant to the cover; or The polymer film is used for packaging. However, the above packaging technology has the defects of low vacuum and complicated process, and the glass or plastic cover has poor characteristics of blocking water vapor or oxygen, and the isolation effect of the organic material from water vapor and oxygen after packaging is still not satisfactory to improve the OLED product. Working life requirements. Therefore, packaging materials and technologies for OLED products require further research and improvement. Summary of the invention

In order to solve the above technical problem, an object of the present invention is to provide an organic light emitting diode having a better packaging effect and a manufacturing method thereof for improving the isolation effect of an organic material of an organic light emitting diode from moisture and oxygen, and improving the operation of the organic light emitting diode. life.

To this end, the embodiments of the present invention provide the following technical solutions:

An organic light emitting diode (OLED) using a film seal, comprising:

Substrate

a transparent electrode layer, an organic light emitting material layer and a cathode metal layer sequentially formed on the substrate; a sealing layer formed on the cathode metal layer;

The sealing layer is a tantalum pentoxide (Ta ₂ 0 ₅ ) film.

Preferably, the ruthenium pentoxide film has a thickness of 50 nm to 500 nm.

Preferably, the organic light emitting diode further includes:

Flexible plastic film, sheet PC plastic or glass;

The flexible plastic film, sheet PC plastic or glass is cured by an ultraviolet curing epoxy curing agent The tantalum pentoxide film is surface bonded to form a flexible or rigid (OLED) device.

Preferably, the organic luminescent material layer is a single luminescent layer structure, or a layered structure in which a multi-color luminescent layer is superposed.

Embodiments of the present invention also provide a method for fabricating an organic light emitting diode using a film seal, including:

Providing a substrate;

A transparent electrode layer, an organic light emitting material layer and a cathode metal layer are sequentially formed on the substrate; and a tantalum pentoxide film is formed on the cathode metal layer.

Preferably, the tantalum pentoxide film is formed by a magnetron sputtering coating process.

Preferably, the magnetron sputtering coating process is specifically:

The ruthenium pentoxide oxide target was directly sputtered using RF magnetron sputtering.

Preferably, the magnetron sputtering coating process is specifically:

The ruthenium metal target is sputtered in an oxygen-containing atmosphere using direct current or intermediate frequency magnetron sputtering.

Preferably, the antimony pentoxide film is formed by a magnetron sputtering coating process at room temperature. Preferably, the transparent electrode layer and the cathode metal layer are formed by a vacuum coating process; after the transparent electrode layer is formed, the organic light-emitting material layer is formed by a vacuum coating process or by introducing a normal pressure dry nitrogen gas by a solution coating process.

Compared with the prior art, the above technical solution has the following advantages:

According to the technical solution provided by the embodiments of the present invention, a tantalum pentoxide film having high geometric density and optical density and a flat surface is formed on the cathode metal layer of the organic light emitting diode to seal the organic material inside the device. The contact of the organic material with water vapor and oxygen is isolated, and the single-layer process of the invention can obtain an organic light-emitting diode with good sealing and good working life and long working life.

BRIEF DESCRIPTION OF THE DRAWINGS In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art description will be briefly described below, obviously, The drawings in the following description are only some of the embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative work.

1 is a schematic structural view of an organic light emitting diode according to Embodiment 1;

2 is a schematic flow chart of a method for fabricating an organic light emitting diode according to Embodiment 2.

detailed description

In order to improve the isolation effect of the organic material of the organic light emitting diode from the moisture and oxygen, and to improve the working life of the organic light emitting diode, the embodiment of the invention provides an organic light emitting diode using a film sealing and a manufacturing method thereof.

The organic light emitting diode includes: a substrate; a transparent electrode layer, an organic light emitting material layer and a cathode metal layer sequentially formed on the substrate; a sealing layer formed on the cathode metal layer; and the sealing layer is tantalum pentoxide (Ta ₂ 0 ₅ )film.

The method for fabricating an organic light emitting diode includes: providing a substrate; sequentially forming a transparent electrode layer, an organic light emitting material layer and a cathode metal layer on the substrate; and forming a tantalum pentoxide film on the cathode metal layer.

According to the technical solution provided by the embodiments of the present invention, a tantalum pentoxide film having high geometric density and optical density and a flat surface is formed on the cathode metal layer of the organic light emitting diode to seal the organic material inside the device. The organic material and the water vapor and the oxygen are isolated, and the single-layer process of the invention can obtain an organic light-emitting diode having a good sealing and a long working life.

The above is the core idea of the present application. The technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Rather than all embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

Many specific details are set forth in the following description in order to facilitate a full understanding of the invention, but the invention may be practiced in other embodiments other than those described herein. A similar generalization may be made without departing from the spirit of the invention, and thus the invention is not limited by the specific embodiments disclosed below.

2 is a detailed description of the present invention in conjunction with the accompanying drawings. In the detailed description of the embodiments of the present invention, the cross-sectional views showing the structure of the device may not be partially enlarged according to the general proportion, and the schematic diagram is only an example, which should not be limited herein. The scope of protection of the present invention. In addition, the actual production should include the three-dimensional dimensions of length, width and depth. Embodiment 1:

The embodiment provides an organic light emitting diode with a better packaging effect. As shown in FIG. 1 , it is a schematic structural diagram of the organic light emitting diode, which specifically includes:

Substrate 101 ;

a transparent electrode layer 102, an organic luminescent material layer 103 and a cathode metal layer 104 are sequentially formed on the substrate;

a sealing layer 105 formed on the cathode metal layer;

The sealing layer 105 is a tantalum pentoxide (Ta ₂ 0 ₅ ) film.

The substrate 101 may include a transparent substrate and an isolation layer. The transparent electrode 102 is formed on the isolation layer. The transparent substrate is usually a glass or a flexible plastic film.

The transparent electrode layer 102, that is, the anode of the organic light emitting diode, is also referred to as a lower electrode. Since the light is to be emitted through the transparent electrode layer 102, the layer is usually selected from an indium tin oxide film (ITO).

The organic light-emitting material layer 103 is divided into two types. If it is a small-molecule OLED, the organic light-emitting material layer has a layered structure, that is, a hole transport layer, a light-emitting layer, and an electron transport layer. If it is a polymer OLED, it is organic. The luminescent material layer is a single layer structure or a superposition of a multi-color single layer.

The cathode metal layer 104 is also referred to as an upper electrode, which is usually an aluminum thin film layer or an alloy thin film layer or the like. The tantalum pentoxide film has high geometric density and optical density, and has a flat surface, which is very suitable as a sealing layer for insulating organic materials from water vapor and oxygen. The thickness of the tantalum pentoxide film may preferably be between 50 nm and 500 nm.

Meanwhile, when the organic light emitting diode is used to display characters and images, the transparent electrode layer 102 The upper and lower grid-like insulating layers may be further included to form the sub-pixels by isolating the strip-shaped transparent electrodes. In addition, in practical applications, the organic light emitting diode may further include: a flexible plastic film, a sheet of PC plastic or glass;

The flexible plastic film, sheet-like PC plastic or glass is bonded to the tantalum pentoxide film surface by an ultraviolet curing epoxy curing agent.

A flexible or rigid OLED device can be obtained by gluing a flexible plastic film, sheet-like PC plastic or glass on the surface of the tantalum pentoxide film. As shown in Fig. 1, 106 is a transparent or opaque flexible plastic film, sheet-like PC plastic or glass.

In the organic light emitting diode provided in this embodiment, the cathode metal layer is covered with a tantalum pentoxide film having high geometric density and optical density and a flat surface to seal the organic material inside the device, and the organic material is isolated. Water vapor and oxygen, the organic light emitting diode generates a process cartridge, and has a good sealing effect of the organic material, which can effectively improve the working life of the organic light emitting diode.

Embodiment 2:

Corresponding to the organic light emitting diode provided in the first embodiment, the present embodiment provides a method for manufacturing such an organic light emitting diode. As shown in FIG. 2, it is a schematic flowchart of the method, which includes the following steps:

Step S201, providing a substrate; wherein the substrate may include a transparent substrate and a separation layer, and the transparent substrate is usually a glass or a flexible plastic film.

Step S202, sequentially forming a transparent electrode layer, an organic luminescent material layer and a cathode metal layer on the substrate;

Step S203, forming a tantalum pentoxide film on the cathode metal layer.

In the above step S202, the transparent electrode layer may be formed on the isolation layer of the substrate, and specifically, may be formed by a vacuum plating process. The transparent electrode layer may specifically be an Indium Tin Oxides (ITO) film.

After the preparation of the transparent electrode layer, the organic light-emitting material layer is formed by a vacuum coating process or by introducing a normal pressure dry nitrogen gas by a solution coating process. The cathode metal layer may also be formed by a vacuum coating process, and may specifically be an aluminum thin film layer or an alloy thin film layer.

In the above step S203, the antimony pentoxide film may be formed by a process such as thermal oxidation, chemical vapor deposition, ion beam sputtering, magnetron sputtering, electron beam evaporation or pulsed laser deposition, wherein the radio frequency magnetron sputtering is performed. It has the advantages of large film forming area, single process, suitable for continuous production, and the like, and is the preferred method adopted in the present embodiment.

In the above process for preparing a ruthenium pentoxide film by a magnetron sputtering process, a ruthenium pentoxide oxide target can be directly sputtered in a pure Ar or an oxygen-doped atmosphere by RF magnetron sputtering to form a pentoxide. A tantalum film; or a tantalum metal target is sputtered in an oxygen-containing atmosphere using direct current or medium frequency magnetron sputtering to form a tantalum pentoxide film.

Since sputtering power and oxygen are two important parameters for preparing a tantalum pentoxide film, it is preferable to use a low sputtering power and an oxygen-containing working gas working environment in this embodiment to reduce defects of the tantalum pentoxide film. A film having a smooth surface and a high density is obtained.

At the same time, in order to avoid the long and complicated manufacturing process caused by high temperature treatment, the diffusion of components between different functional film layers and the formation of additional compounds at the interface create new disadvantages, affect the structure of the thin film device, and weaken it. Defects such as function and performance. In the method provided in this embodiment, the magnetron sputtering coating process is performed under a room temperature environment.

In this embodiment, it is preferable to control the thickness of the deposited tantalum pentoxide film to be between 50 nm and 500 nm by controlling the sputtering power and time.

In addition, after forming the ruthenium pentoxide film, according to actual application requirements, the method may further include: bonding a flexible plastic film, a sheet of PC plastic or glass to the surface of the ruthenium pentoxide film, and bonding the glue The agent may be an epoxy resin, and through the above steps, a flexible or rigid OLED device can be obtained.

In the method for fabricating an organic light emitting diode provided in this embodiment, a tantalum pentoxide film having a high geometric density and an optical density and having a flat surface is formed on the cathode metal layer to seal the organic material inside the device. The organic material and the water vapor and the oxygen, the method has a single process, and can obtain the organic light-emitting with the better sealing effect of the organic material and the high working life. Diode.

The various parts of this manual are described in a progressive manner. Each part focuses on the differences from the other parts. The same similar parts between the parts can be referred to each other. The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments are obvious to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not intended to be limited to the embodiments shown herein, but the

Claims

Rights request

An organic light emitting diode (OLED) sealed with a film, comprising: a substrate;

The sealing layer is a tantalum pentoxide (Ta ₂ 0 ₅ ) film.

2. The organic light emitting diode according to claim 1, wherein:

The tantalum pentoxide film has a thickness of 50 nm to 500 nm.

3. The OLED according to claim 1, further comprising: a flexible plastic film, a sheet of PC plastic or glass;

The flexible plastic film, sheet-like PC plastic or glass is glued to the tantalum pentoxide film by an ultraviolet curing epoxy curing agent to form a flexible or rigid (OLED) device.

4. The OLED according to claim 1, wherein:

The organic light emitting material layer is a single light emitting layer structure or a layered structure in which a multicolor light emitting layer is superposed.

5. A method of fabricating an organic light emitting diode using a film seal, comprising: providing a substrate;

6. The method of fabricating an organic light emitting diode according to claim 5, wherein the tantalum pentoxide film is formed by a magnetron sputtering coating process.

7. The method of fabricating an organic light emitting diode according to claim 6, wherein the magnetron sputtering coating process is specifically:

8. The method of fabricating an organic light emitting diode according to claim 6, wherein the magnetron sputtering coating process is specifically:

9. The method of fabricating an organic light emitting diode according to claim 6, wherein: The tantalum pentoxide film is formed by a magnetron sputtering coating process at room temperature.

The method of fabricating an organic light emitting diode according to claim 5, wherein: the transparent electrode layer and the cathode metal layer are formed by a vacuum plating process;

After the transparent electrode layer is formed, the organic light-emitting material layer is formed by a vacuum coating process or by introducing a normal-pressure dry nitrogen gas using a solution coating process.