TWI286371B - OLED packaging method - Google Patents

Abstract

An OLED packaging method is provided. Separately handle the process of a barrier layer composed by organic adhesion layer and inorganic barrier layer, and OLED device process. Then coat glue seal agent to cover the substrate and let the barrier layer seal the OLED device to achieve the water-proof and moisture-proof purposes, hence lengthen the OLED device lifetime. Finally utilize UV light or low-temperature baking to reach the glass transition temperature of the organic adhesion layer and therefore tightly combine the two parts. The cycle time can be reduced when introducing the said method.

Description

1286371 V. INSTRUCTION DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention: The present invention relates to a method of packaging an organic illuminator (Organic Electro-Luminescence Element; or Light Emitting Diode; 0 LED) wafer, in particular, a protective layer It can be made separately from the organic light-emitting two body, and finally the two are attached together by an adhesive. Prior Art: Organic light-emitting diodes (OLEDs) or EL elements are usually formed by an organic light-emitting material layer as an interlayer formed in a pair of electrically opposite electrode layers, and electrons are emitted from an electrode layer to the organic light-emitting material. The layer, the hole is directed by the other electrode to the layer of organic light-emitting material, and the electrons and holes will thus be combined with the layer of organic light-emitting material to generate light. Compared with conventional bulb-type illuminating elements, EL components have excellent shock resistance and thinness, making them ideal as display components. However, on the other hand, EL elements have also been found to emit light after a period of use - especially the brightness and uniformity of the light and the initial phase of the light-emitting phase.

Than, there is some degree of degradation. According to research, the most important reason is that E L components have been found to easily absorb moisture. And, once adsorbed on the surface of the organic EL element, it becomes a part of the composition of the organic EL element. Water vapor then invades the defects of the organic E L component. It is quickly found that there is dark spot generation that does not emit light because the power supply at this location is blocked by moisture. Therefore, prevention of excessive moisture in organic EL elements is an important issue. Kawami et al. obtained U.S. Patent No. 5,882,761 entitled "Organic EL"

Page 5 1286371 V. Description of the invention (2) E 1 e m e n t is an embodiment for preventing moisture intrusion. Referring to FIG. 1, the organic light-emitting body 6 includes an ITO (indium tin oxide electrode) 3, an organic light-emitting layer 4, and a cathode 5, which are sealed by a transparent sealed container 1 to prevent moisture intrusion. The hermetic container 1 comprises a glass substrate 2 and a glass package 7 carrying a dry material 8 sealed with an encapsulant 9.

The method provided by Kawami is simple, but it has two major drawbacks. One is that this structure will completely lose the flexibility of the entire EL element. In addition, the entire component is also increased in thickness due to the addition of a container. Another conventional method can improve the above problems in the Kawami patent. Please refer to U.S. Patent No. 6,1,8,2,7,7, issued by S u z u k i et al. The title is NORGNIC ELECTROLUMINESCENCENT DEVICE HAVING A PROTECTIVE COVERING COMPRISING ORGANIC AND INORGANIC LAYERS". Basically, the structure proposed by S uzuki, please refer to Figure 2. The organic light-emitting element U comprises an anode 1 一, a hole transmission layer 1 2, an organic The luminescent layer 14 , an electron transport layer 16 and a cathode 18 are sequentially stacked on a substrate 24. The organic light-emitting element U is further protected by an organic barrier layer 20 and an inorganic barrier layer 2 2 as protective layers. In general, the organic barrier layer 20 has a good affinity with a metal or a cathode of a composite material, and can cover the defects of the light-emitting element U and smooth the entire surface. The inorganic barrier layer 2 2 such as S i 〇 2, S i 0, G e 0, A 1 20

1286371 V. DESCRIPTION OF THE INVENTION (3) 3. The T i N or S i 30 shore forms a protective layer after the use of a vapor depos i t i on or a Tibetan clock method (s p u 11 e r i n g ). The organic barrier layer 2 2 has better water repellency than the organic barrier layer 20 . In the above-mentioned process, there are actually no small traps, and we must be especially careful or we will abandon them. For example, the organic barrier layer 20 is typically a multilayer film layer. Among them, the starting material layer is particularly important, and may be selected from photo curable monomers ^ oligomers, thermoplastic type, and glass transition temperature polymers or low molecules. Thermoplastic resins need to be resistant to moisture to a certain extent, while photocurable monomers and ο 1 i g 〇 m e r s require low volatility. It is formed by injection molding (c a s t i n g ), or spin coating or vacuum evaporation, and the injection molding or spin coating productivity is faster than vacuum evaporation, but care must be taken that moisture directly penetrates into the organic light emitting element U. Otherwise, the components will not illuminate until the product is sold. Vacuum evaporation is relatively less of the above problem. Since it is carried out under a reduced pressure condition, the comparison prevents the incorporation of moisture into the air. However, the disadvantage is that for large-area displays, the evaporation time will take a long time and the production capacity will be limited. In addition, when a polymer material is applied, heat treatment is usually required to be close to its glass transition temperature to soften it, and at the same time, the defects of the organic light-emitting element U can be repaired. However, the glass transition temperature of the polymer material must be lower than the glass transition temperature of either layer of the composition of the organic light-emitting element U. Otherwise, the organic light emitting element U will be deteriorated. Summary of the invention:

Page 7 1286371 V. Description of Invention (4) This document discloses a package for an organic EL device, a barrier layer for a de-bonding layer and an inorganic barrier layer, and an EL device for coating a substrate with a sealant. All around, in order to make the barrier layer ^ waterproof and moisture-proof to extend the life of the EL device. External light or low temperature baking to achieve the adhesion of the organic adhesive layer. The method of the present invention can be used to provide a non-stick film. 1 in) 'The inorganic barrier layer and the organic adhesive layer are then applied to the non-stick film, and then a win seal layer is applied to the periphery of the substrate to roll the protective laminate formed on the non-stick film to the containing layer. On the substrate. Finally, after the non-stick film is removed, a UV irradiation treatment is applied to achieve glass transition temperature of the organic adhesive layer. Embodiments: In view of the prior art, the illuminating element is very afraid of the method provided by the water K a warn i, although the flexibility of the EL illuminating element is completely lost, and the volume is also provided by S uzuki. Method < In order to avoid the Kawami method, there are also many questions that must be taken in a special way. In addition, since the organic barrier layer is at least, it will contain organic separation treatment. Then live the EL element, and finally use the purple shift temperature to make the two-stage time (cyc 1 e (release 3 is formed in the 're-rolling or EL element, rubber seal to low temperature baking or degree to make the two tight Intrusion, but intrusion, but it will be too big. But the problem, but lost the original two-layer multilayer film

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1286371 V. INSTRUCTIONS (5) Layers (a starting layer and subsequent coating or deposited layer), together with inorganic barrier layers, must be formed one after the other, especially for large dimensions such as displays. It will be limited, especially if it is formed by evaporation, the productivity will not increase. The present invention can provide a solution to the above problems. The main concept of the present invention is to separately perform the EL element and the protective layer, and finally to bond the two, and recently to achieve the purpose of the two by the illumination heating. As a result, the cycle time of manufacturing can be further shortened. First, as shown in FIG. 3A, the layers required for the EL element include an anode 110, a hole transport layer 112, an organic light-emitting layer 114, an electron transport, a transport layer 1 16 and a cathode 1 18 . The EL element layer 1 is sequentially formed on a substrate 1 2 4. Then, please refer to FIG. 3B to prepare a release fi 1 m 150, and then form a film by evaporation or sputtering. The inorganic barrier layer 1 2 2 having a thickness of less than about 1 // m is on the non-stick film 15 5 . The inorganic barrier layer 12 2 may be selected from one of ITO, Si 〇 2, SiO, GeO, Al 2 〇 3, TiN, or Si 3 〇 4f. Next, an organic adhesive layer 130 is formed on the inorganic barrier layer 1 2 2 . The organic adhesive layer 130 may be selected from the group consisting of polyethylene (PE), polypropylene (p〇lypr〇pylene; pp), epoxy resin (ep〇xy resin), or acyclic resin (acrylic resin) ( Acryiic resin) and the like.

Brief Description of the Drawings The preferred embodiment of the present invention will be explained in more detail in the following description with the following figures. Fig. 1 is a schematic view showing the first moisture-proof package of a conventional EL element. FIG. 2 is a schematic diagram showing a second moisture-proof package of a conventional EL element. 3A to 3C are schematic views showing the process of moisture-proof packaging according to a preferred embodiment of the present invention. Figure number comparison description: 2 Glass substrate 3 IT 0 Anode 4 Organic light-emitting layer 5 Cathode 7 Glass package 8 Dry material 9 Encapsulant 1 Closed container 10 Anode 12 Hole transport layer 14 Organic light-emitting layer 16 Electron transport layer 18 Cathode 20 Organic Barrier layer 22 inorganic barrier layer U light-emitting element 24 substrate 110 anode 112 hole transport layer 114 organic light-emitting layer 116 electron transport layer 118 cathode 122 inorganic barrier layer 130 organic adhesive layer 124 substrate 150 non-stick film 140 glue sealant 100 EL light-emitting element

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Claims (1)

1286371 VI. Patent Application Range 1. A method for packaging an organic light-emitting (EL) device, comprising at least the steps of: providing a substrate and an EL element formed on the substrate; providing a release film; forming an inorganic a barrier layer on the non-stick film; forming an organic adhesive layer on the inorganic barrier layer; forming a seal layer around the substrate; using the sealant layer and the organic adhesive layer to bond the organic adhesive layer An outer surface of the EL element; removing the non-stick layer; Heat treatment is applied to bring the organic adhesive layer into close contact with the outer surface of the EL element. 2. The method of claim 1, wherein the inorganic barrier layer is selected from the group consisting of IT〇, SiO2, Si〇, Ge〇, A1 2〇3, TiN, and Si 3〇4. One of the groups and any combination thereof. 3. The method of claim 1, wherein the organic barrier layer is selected from the group consisting of polyethylene (PE), polypropylene (PP), epoxy resin, and One of a group consisting of a cyclic resin (A cry 1 icresi η ) and any combination thereof. 4. The method of claim 1, wherein the above sealing layer Page 12 1286371 VI. The scope of application for the patent is selected from the group consisting of polyethylene (PE), polypropylene (PP), epoxy resin and acyclic resin (A cry 1 icresi η ). One of the groups and any combination thereof. 5. The method of claim 1, wherein the bonding step is performed by roller pressing. 6. The method of claim 1, wherein the bonding step is performed by roller pressing. 7. The method of claim 1, wherein the heat treatment is performed by baking at less than 120 °C. 8. The method of claim 1, wherein the heat treatment is performed by irradiation with ultraviolet light of less than 120 °C.