JP3692334B2 - Organic EL panel and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an organic EL panel capable of preventing permeation of oxygen and moisture, and more particularly, to a protective film for protecting an organic EL element from moisture and oxygen, and an inorganic insulating thin film. The present invention relates to an organic EL panel capable of preventing the penetration of oxygen and moisture existing outside an organic EL element by laminating an organic or polymer thin film and a method for manufacturing the same.
[0002]
[Prior art]
In general, an organic electroluminescence display (OELD) using an organic EL element has a response speed that is 30,000 times faster than a liquid crystal display (LCD) that is currently commercialized. Therefore, it is possible to realize a moving image, and has an advantage that a wide viewing angle and high luminance can be obtained as a unique light emitting element.
[0003]
In such an organic EL element, as shown in FIG. 1, an anode electrode 2 is formed on a substrate 1, an organic layer 3 is formed thereon, and a cathode electrode 4 is formed on the organic layer 3. The anode electrode 2 and the cathode electrode 4 are connected to a power source 5.
[0004]
The organic layer of the EL device thus configured must include a light emitting layer, and includes an electron transport layer, an electron injection layer, a hole transport layer, and a hole injection layer in order to improve light emission efficiency.
[0005]
Here, when a positive (+) voltage is applied to the anode electrode 2 and a negative (−) voltage is applied to the cathode electrode 4 by the power source 5, holes are supplied from the anode electrode 2 to the organic layer 3. The light reaches the light emitting layer through the hole injection layer and the hole transport layer present in the organic layer 3.
[0006]
Electrons are supplied from the cathode electrode 4 to the organic layer 3 and reach the light emitting layer through the electron injection layer and the electron transport layer present in the organic layer 3. As a result, the light emitting layer of the organic layer 3 emits light while recombining the injected holes and electrons, and is transmitted to the outside through the substrate.
[0007]
In such an organic EL element, a phenomenon in which the characteristics of the organic EL element are hindered due to the organic substance of the organic layer 3 easily reacting with oxygen and moisture in the atmosphere occurs.
[0008]
FIG. 2 is a view showing that a capsule for protecting an organic layer of a conventional organic EL element from external oxygen and moisture is sealed, and an anode 12 is formed on an upper portion of a substrate 11. An organic layer 13 is formed on the anode 12, and a cathode 14 is formed on the organic layer 13 to form an organic EL element. The polarity of the anode is blocked around the organic layer 13 and the cathode 14. An insulating layer 18 is formed, and a cathode separating partition for isolating the cathodes 19 is formed on the insulating layer 18.
A capsule 15 surrounds the cathode 14 formed on the organic layer 13 and the cathode separation barrier to block the penetration of oxygen and moisture from the outside into the organic layer 13, and is sealed on the anode 12. It is sealed with a stopper 17.
[0009]
Such a capsule 15 contains the absorbent 16 inside, and plays a role of blocking moisture penetrating the organic layer 13 at an early stage.
[0010]
Therefore, the technology for sealing the capsule to the substrate in order to protect the organic EL element from external influences is as follows: 1) increasing the thickness of the panel, and 2) a sealing agent for bonding the capsule and the substrate. The life of the device may be shortened by the gas released from the sealant in the plastic process of 3). 3) There are still factors that allow external oxygen or moisture to penetrate through the sealant. 4) Sealing. There is a possibility that thermal loss of the device may occur depending on the plastic condition of the agent. 5) Increasing the material cost of device fabrication by including a hygroscopic agent to remove the moisture that exists in the capsule or penetrates. 6) There was a problem in that the equipment investment cost for the process of adhering the substrate and capsules to the outside air was increased.
[0011]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described problems, and is a subsequent process of a process for manufacturing an organic EL element, and an inorganic insulating thin film and an organic or polymer thin film for protecting the organic EL element from external influences. It is an object of the present invention to provide a method for manufacturing an organic EL panel that can block oxygen and moisture permeated from the outside by stacking layers.
[0012]
Another object of the present invention is to provide an organic EL panel that can be applied to a portable display by manufacturing an organic EL panel that is lightweight and thin.
[0013]
[Means for Solving the Problems]
In order to achieve the above object, the method of manufacturing an organic EL panel capable of preventing the penetration of oxygen and moisture according to the present invention is to protect an organic EL element on the upper part of the panel on which the organic EL element is formed. Forming a first protective film; forming an inorganic insulating film on the first protective film; and second preventing oxygen and moisture from penetrating from the outside on the inorganic insulating film. And a step of laminating a protective film.
[0014]
The organic EL panel capable of preventing the permeation of oxygen and moisture according to the present invention for achieving the other object includes a panel in which an organic EL element is formed and the organic EL element. A first protective film formed on the upper part of the panel for protecting the organic EL element, an inorganic insulating film formed on the first protective film, and formed on the upper part of the inorganic insulating film. And a second protective film capable of preventing moisture permeation.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings.
[0016]
FIG. 3 is a cross-sectional view of an organic EL panel manufactured by the method of manufacturing an organic EL panel according to the present invention. The organic EL element includes an anode 21 formed on an upper portion of a substrate 20; An organic layer in which a hole injection layer / hole transport layer 22, a light emitting layer 23, and an electron transport layer / electron injection layer 24 are sequentially stacked; a cathode 25 stacked on top of the organic layer; In order to separate the polarities, a partition wall 27 formed on the anode 21 around the organic layer is included.
[0017]
A protective film for preventing permeation of oxygen and moisture is laminated on the upper part of the panel on which the organic EL element is formed. Here, the protective film is formed to protect the organic EL element. A first protective film 28, an inorganic insulating film 29 formed on the first protective film 28, and a second protective film 30 capable of preventing the penetration of moisture from the outside into the upper portion of the inorganic insulating film 29. Are stacked in order.
[0018]
Accordingly, in the present invention, a protective film for preventing the penetration of oxygen and moisture is laminated on a panel on which an organic EL element having an organic layer that emits light and is interposed between an anode and a cathode is formed. It is characterized by that.
[0019]
In order to further prevent the organic EL panel from penetrating oxygen and moisture from the outside, another inorganic insulating film and a second protective film may be sequentially and repeatedly stacked on the second protective film 30. it can.
[0020]
A method of manufacturing an organic EL panel in which such a multilayer protective film is laminated includes a step of forming a first protective film for protecting the organic EL element on the panel on which the organic EL element is formed, A step of forming an inorganic insulating film on the upper portion of the first protective film; and a second protective layer having high strength to prevent external moisture from penetrating the upper portion of the inorganic insulating film and to prevent damage to the device. Laminating the film.
[0021]
In the step of forming the first protective film on the top of the panel on which the organic EL element is formed, the protective film is any one of SiN _x , SiO ₂ , Al ₂ O ₃ , Ta ₂ O ₅ , and Y ₂ O ₃ . One or a combination of two or more of them can be laminated to form.
[0022]
The first protective film is formed of SiN _x capable of preventing damage to the organic EL element and protecting the organic film, and then, SiO ₂ , Al ₂ O ₃ , Ta ₂ O _{5 on the} SiN _x. , Y ₂ O ₃ can also be laminated.
[0023]
Further, in the step of forming a first protective film on the upper part of the panel on which the organic EL element is formed, the first protective film is formed by a chemical vapor deposition process (CVD), thermal evaporation, or electron beam evaporation ( One of E-Beam Evaporation and Sputtering processes is selected and manufactured.
[0024]
In addition, in the step of laminating a second protective film having high strength to prevent oxygen and moisture from permeating from the outside and preventing damage to the element, the second protective film is formed on the inorganic insulating film. May be laminated by selecting any one of an organic film and a polymer film.
[0025]
After the step of laminating a second protective film capable of preventing permeation of moisture from outside on the inorganic insulating film, the step of forming the inorganic insulating film and the step of laminating the second protective film; By repeating the steps one after another, the permeation of oxygen and moisture can be further prevented.
[0026]
A polymer film excellent in preventing permeation of oxygen and moisture from the outside should be formed on the inorganic insulating film, and it is most desirable to use parylene or a fluororesin.
[0027]
Here, the fluororesin polymer film can be formed by depositing a fluororesin by a dipping method or other methods.
[0028]
FIG. 4 is a diagram illustrating a state in which a polymer film using parylene according to the present invention is cured. Parylene in a dimer state is heated at a temperature of about 150 ° C. by a vapor deposition machine. After forming the parylene in the body state, it is heated at a temperature of 680 ° C., and the parylene in the monomer state is sprayed onto the upper part of the panel on which the organic EL element is formed, and cured at the atmospheric temperature and the pressure of 0.1 Torr The final polymer film is formed by forming a polymer state.
[0029]
In addition, an organic EL element is formed on the upper surface of the panel on which the organic EL element on which the inorganic insulating film is formed is formed with a monomer-state parylene at a temperature of about 680 ° C. and a pressure of 0.5 Torr. After vapor deposition on the top of the panel, curing is performed at an atmospheric temperature and a pressure of 0.1 Torr, so that a final polymer film can be formed in a polymer state.
[0030]
【The invention's effect】
As described above, according to the present invention, the organic EL panel on which the protective film for preventing the permeation of oxygen and moisture can be prevented from being penetrated from the outside. It has an effect that it can be applied to a portable display.
[0031]
Although the preferred embodiments of the present invention have been described above, various modifications may be made by those skilled in the art without departing from the scope of the claims of the present invention.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a configuration for explaining a schematic operation of an organic EL element.
FIG. 2 is a cross-sectional view showing that a capsule for protecting an organic layer of a conventional organic EL element from external oxygen and moisture is sealed.
FIG. 3 is a cross-sectional view of an organic EL panel manufactured by an organic EL panel manufacturing method according to the present invention.
FIG. 4 is a view showing a state in which a polymer film according to the present invention is cured.
[Explanation of symbols]
20 substrate 21 anode 22 hole injection layer / hole transport layer 23 light emitting layer 24 electron transport layer / electron injection layer 25 cathode 26 insulating layer 28 first protective film 29 inorganic insulating film 30 second protective film

Claims (8)

Forming a first protective film for protecting the organic EL element on top of the panel on which the organic EL element is formed;
Forming an inorganic insulating film on top of the first protective film;
Laminating a second protective film for preventing penetration of oxygen and moisture from the outside on the inorganic insulating film,
The step of forming the first protective film includes forming SiN _x capable of preventing damage to the organic EL element and protecting the organic film, and then forming SiO ₂ , Al ₂ O ₃ , Ta on the SiN _{x. One of 2} O ₅ and Y ₂ O ₃ is laminated,
A method for producing an organic EL panel capable of preventing permeation of oxygen and moisture.   In the step of forming a first protective film for protecting the organic EL element on the panel on which the organic EL element is formed, the first protective film includes a chemical vapor deposition process, thermal vapor deposition, electron beam vapor deposition, and the like. 2. The method for producing an organic EL panel according to claim 1, wherein the organic EL panel is formed by any one of the steps of the sputtering method.   In the step of laminating a second protective film capable of preventing permeation of oxygen and moisture from the outside on the inorganic insulating film, the second protective film is either an organic film or a polymer film. The method for producing an organic EL panel according to claim 1, wherein:   After the step of laminating the second protective film for preventing the penetration of oxygen and moisture from the outside on the inorganic insulating film, the step of forming the inorganic insulating film and the step of laminating the second protective film are sequentially performed. 2. The method for producing an organic EL panel according to claim 1, which is repeated.   In the step of laminating a second protective film for preventing the penetration of oxygen and moisture from the outside on the inorganic insulating film, the second protective film is cured after depositing a dimer or monomer parylene. 2. The method for producing an organic EL panel according to claim 1, which is a parylene polymer film formed or a fluororesin polymer film formed by a dipping method. A panel on which an organic EL element is formed;
The top of the panel to the organic EL element is formed, for protecting the organic EL device, any on top of SiN _x in SiN _x Toko of _{SiO 2, Al 2 O 3,} Ta 2 O 5, Y 2 O 3 A first protective film that is a multilayer film in which one of the layers is laminated;
An inorganic insulating film formed on the first protective film;
Layered on top of the inorganic insulating film, prevents penetration of oxygen and moisture from the outside, and includes a second protective film having high strength to prevent damage to the element, preventing penetration of oxygen and moisture Organic EL panel that can be.   The organic EL panel according to claim 6, wherein the second protective film is one of an organic film and a polymer film.   8. The organic EL panel according to claim 7, wherein the polymer film is parylene or a fluororesin.

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