JP3826076B2 - Organic electroluminescent device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a kind of organic electroluminescent device, and more particularly, to an organic electroluminescent device capable of increasing the moisture absorption conduit to suppress the generation of dark spots and ensure the light emission quality.
[0002]
[Prior art]
An organic electroluminescent device (hereinafter referred to as an organic EL device) has a large viewing angle, a short response time, a thin display, a low power consumption, a simple manufacturing process, and an impact resistance. Since it has the advantage that it can emit a full-color light source without the need for a backlight light source, it is used in a new generation display panel and attracts attention in various directions.
[0003]
FIG. 1 is a structural cross-sectional view of a known organic EL device, in which a lower electrode (transparent electrode) 12 is formed on a substrate 11, and a hole injection layer and a hole transport layer are disposed at appropriate positions of the lower electrode 11. An organic layer 13 having an organic launch layer or an electron transport layer, a counter electrode 14 and an isolation sealing layer 15 are sequentially formed. In the organic EL device, electrons or holes generated individually by the two electrodes 11 and 14 are combined in the organic layer 13 to excite the organic emitting layer and emit light. It is not possible to prevent the generation of a heat source during this process, and this heat source is combined with moisture or oxygen gas already present in the isolation sealing layer 15 and is oxidized on the surface of the organic layer 13. In addition to forming a phenomenon, a dark spot is generated, and the presence of the dark spot affects the light emission quality such as the light emission intensity and light emission uniformity of the organic EL device. In severe cases, the service life of the organic EL device is greatly shortened. did.
[0004]
In order to solve the defect in the visible image where dark spots occur, the industry is making efforts to improve the structure of various organic EL devices. For example, in JP-A-363890 or JP-A-5-114486. Describes that liquid fluorocarbon (liquid fluorinated crbon) is placed in the isolation sealing layer 15, thereby effectively removing a heat source generated during light emission. In JP-A-5-41281, a liquid dehydrating agent such as synthetic zeolite in the isolation sealing layer 15 is mixed into liquid fluorine carbide, and thereby the apparatus. It describes the neutralization and removal of moisture and moisture present in the vicinity. In US Pat. No. 5,962,962 “Method of encapsulating organic electroluminescence device and organic electroluminescence device”, silicon oil or silicon oil is used to protect the liquid by using gas to protect the liquid. Are listed.
[0005]
Each of the patents described above has an effective reduction effect on the occurrence of dark spots. However, all the dehydrating agents such as fluorine carbide to be used exist in a liquid state and have certain difficulties in the manufacturing process, which is disadvantageous for IC matching and manufacturing cost reduction.
For this reason, there is a structure of the second type organic EL device. For example, US Pat. No. 5,882,761 “Organic EL element” in FIG. 2 has a dry substrate 17 on the inner surface of the isolation sealing layer 15. The internal gap 19 is fixed between the fixed electrode 14 and the counter electrode 14, and the moisture and moisture present in the isolation sealing layer 15 is absorbed by the dry substrate 17 existing in a solid form, and the effect of suppressing the occurrence of dark spots is achieved. is doing.
[0006]
Although this patent solves some of the drawbacks of the above-described technology, the following disadvantages existed in this light emitting device technology.
1. The demand for high precision cannot be achieved with respect to the pattern of the organic EL device, and the two electrode edges tend to cause a short-circuit, which causes a crosstalk problem.
2. Since the isolation sealing layer directly covers the substrate surface and there is no support column between them, it is difficult to withstand the impact of external force, and has certain problems even for light and thin device designs.
3. Such an organic EL device structure is difficult to achieve a basic structure of full-color light emission, and the device use range has a certain limitation.
[0007]
[Problems to be solved by the invention]
This provides a kind of new solution to the problems of the above-mentioned various conventional organic EL devices, and provides high precision, impact resistance, and effective dark spot generation suppression with a simple manufacturing process. The problem is whether to achieve the light emission quality.
[0008]
The main object of the present invention is to provide a kind of organic EL device, in which a drying flange having a moisture absorption function is fixed on the upper surface of the isolation rib, thereby making it necessary to refine the device pattern. In addition to helping to achieve this, it is assumed that the device has an enhanced function to absorb moisture and suppress the generation of dark spots.
[0009]
Another object of the present invention is to provide a kind of organic EL device, which is provided with different light emitting layers corresponding to different light emitting regions due to the presence of the separating convex columns, and easily fulfills the requirement of full color light emission. It is assumed that the device is capable.
[0010]
Another object of the present invention is to provide a kind of organic EL device, which is composed of parts that can be obtained by existing manufacturing processes and is therefore advantageous for IC matching.
[0011]
Another object of the present invention is to provide a kind of organic EL device, in which the isolation rib can be a heat radiating rib having a heat radiating function, effectively removing a heat source generated during the light emitting action of the device. At the same time, it is assumed that the device suppresses the generation of dark spots.
[0012]
[Means for Solving the Problems]
Invention 請 Motomeko 1 is an organic electroluminescent device,
A substrate,
At least one lower electrode formed on the substrate;
A plurality of insulating layers having moisture absorption characteristics and insulating characteristics are formed on the partial surface of the lower electrode, and are crossed with the lower electrode, and further have moisture absorption characteristics on the upper surface of the insulating layer. A plurality of insulating layers provided with a dry substrate and having a light emitting region formed between the two insulating layers;
At least one organic layer comprising an organic electroluminescent launch layer and provided on the lower electrode surface of the light emitting region;
At least one counter electrode provided on the surface of the organic layer;
The organic electroluminescent device is characterized by comprising:
A second aspect of the present invention, in the organic electroluminescent device according to claim 1, vertical insulating layer altitude may be higher than the altitude vertical organic layer, and an organic electroluminescent device.
A third aspect of the present invention, in the organic electroluminescent device of claim 1, drying the substrate, characterized in that disposed in succession on the upper surface of the counter electrode, and an organic electroluminescent device .
[0013]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 3 is a structural cross-sectional view of a preferred embodiment of the present invention. As shown in the figure, first, a lower electrode 32 made of a transparent material, for example, ITO is formed on a substrate 31, and various film formation and patterning such as spin coating, dipping, vapor deposition, sputtering, and etching are performed. Using the method, the isolation rib 38 present in a crossing manner on the partial surface of the lower electrode 32, and the drying flange 35 having a cross-sectional area larger than the isolation rib 38 on the upper surface of the isolation rib 38 are formed. The bottom is a non-light emitting region 337, the space between the two non-light emitting regions 337 is a light emitting region 335, and then, generally, the surface of the lower electrode 32 of the light emitting region 335 is formed by a known film deposition method such as vapor deposition or sputtering. In turn, an organic layer 33 with at least one organic emitting layer, a counter electrode 34 and all Isolating sealing layer 36 covering the formed requirement is formed.
[0014]
Among them, the organic layer 33 can be selected from one of an organic layer (B) capable of projecting blue light, a green light organic layer (G), a red light organic layer (R), or a combination thereof. The isolation rib 38 is made of a material having an insulating property, for example, silicon oxide, silicon nitride, nitrogen silicon oxide, TEOX-oxide, USG, silicon oxide / silicon nitride composite stack layer (ON), silicon oxide / silicon nitride. Formed with elemental / silicon oxide composite stack layer (ONO), PSG, BPSG and BSG, and due to its insulating isolation characteristics, a minute amount between the two electrodes caused by the contact between the lower electrode 32 and the counter electrode 34 is thoroughly The occurrence of short-circuiting and crosstalk is prevented, and the presence of the isolation rib 38 supports the isolation rib 38 at multiple locations to enhance the impact resistance against the external force and achieve the requirement for pattern refinement.
[0015]
In addition, since the drying flange 35 achieves the requirement to absorb moisture and moisture existing in the isolation sealing layer 36, the material to be selected is PSG, BPSG, BSG, MgO, CaO, SrO, BaO and the like having a moisture absorbing function. These materials are made of one of the alkaline earth metal oxides of these materials, and these materials belong to chemical absorption when combined with moisture and therefore once absorbed, the water molecules are once again absorbed. Without being released, it is possible to meet the dry environment requirements in the isolation sealing layer 36, which is very useful for suppressing the occurrence of dark spots and ensuring display quality. The materials described above also have insulating isolation properties, thereby helping to reduce crosstalk problems.
[0016]
Naturally, one important purpose of the drying flange 35 is to refine the pattern of the organic EL device, and therefore can be separated from the organic layer 33 and the counter electrode 34, and therefore the height position at which it exists is the US patent. It can be substituted for the internal gap 19 of the conventional structure described in US Pat. No. 5,882,761 (see FIG. 2) . Thus, in another embodiment of the present invention, the drying flange 35 is made of a fully dry material as described in US Pat. No. 5,882,761, such as alkali metal oxide compound, alkaline earth metal oxide ( Alkaline earth metal oxide compound, sulfate, metal halide, and perchlorate, and by isolating contact between the above-described chemical and organic layer 38 at the height of the isolation rib 38, The organic layer 33 is not damaged, and the isolation sealing layer 36 is supported to have a function of enhancing the impact resistance.
[0017]
In addition, the drying flange 35 and the isolation rib 38 of the present invention can select a polymer material, and achieve the purpose of maintaining the drying in the isolation sealing layer 36 by utilizing the moisture absorption characteristics of the polymer material. However, when selecting a polymer material, the components are put in an oven before the organic layer 33 is deposited and baked at a high temperature (about 100 ° C. to 300 ° C.) to adsorb the adsorbed water molecules or oxygen gas. Remove.
[0018]
Further, shown in FIG. 4 is a structural display diagram of another embodiment of the present invention. As shown in the figure, an insulating layer 41 having an insulating property is provided between the bottom end of the isolation rib 385 and the lower electrode 32, and the insulating layer 41 is tightly adhered to the organic layer 33, and the lower portion is thoroughly removed. All possible short circuit paths between the electrode 32 and the counter electrode 34 are blocked, so that the isolation rib 385 and the drying flange 35 are made of the same material, for example PSG, BPSG, BSG, MgO, CaO, SrO, BaO and other alkalis. It can be formed of earth metal oxide compound, alkali metal oxide compound, sulfate, metal halide, perchlorate, and isolation layer 36. Reaching the demand to keep dry forever Can be made.
[0019]
Of course, the isolation rib 385 and the drying flange 35 can be formed into an integral conical isolation rib by direct etching.
[0020]
Also shown in FIG. 5 is a structural cross-sectional view of another embodiment of the present invention, and as shown, this embodiment provides good heat dissipation instead of the isolation rib 385 in the above-described embodiment. A heat radiating rib 387 having a function is adopted, and the heat radiating rib 387 is made of a metal-containing compound such as copper, gold, silver, tungsten, molybdenum, aluminum nitride, aluminum oxide, magnesium oxide, beryllium oxide, titanium diboride, or boron nitride, Any of non-metal heat dissipation compounds such as silicate resin and silicon carbide can be formed. In this way, the heat radiation rib 387 is used to remove the heat source generated during the light emitting action of the organic layer 33, and the moisture present in the isolation sealing cover 365 is absorbed using the drying flange 35 located on the upper surface of the heat radiation rib 387. The organic layer 33 and the counter electrode 34 are protected under a double protection action to prevent oxidative attack and suppress the occurrence of dark spots.
[0021]
Finally, shown in FIG. 6 is a structural cross-sectional view of another embodiment of the present invention. As shown, in this embodiment, a dry substrate 357 formed of a dry material is directly connected to the insulating layer 41. And the organic layer 33 is covered and protected by the second electrode (counter electrode 34) and the insulating layer 41, so that the dry substrate 357 can be prevented from being damaged. Then, the requirement for absorption of moisture and moisture already existing in the isolation sealing layer 367 is completed without using the heat radiating rib 387 in combination. Of course, it is also possible to lay the dry material directly on the surface of the counter electrode 34 and the insulating layer 41 so that the dry substrate 367 having a larger area can be obtained.
[0022]
【The invention's effect】
In summary, the present invention provides a kind of organic EL device, which is an organic EL device that increases the number of moisture ducts and suppresses the generation of dark spots and ensures the light emission quality. Therefore, the present invention has novelty, inventive step and industrial utility value. It should be noted that the embodiments described above do not limit the scope of the present invention, and any modification or alteration of details that can be made based on the present invention shall belong to the claims of the present invention.
[Brief description of the drawings]
FIG. 1 is a structural cross-sectional view of a known first type organic EL device.
FIG. 2 is a structural cross-sectional view of a known second type organic EL device.
FIG. 3 is a structural cross-sectional view of a preferred embodiment of the present invention.
FIG. 4 is a structural cross-sectional view of another embodiment of the present invention.
FIG. 5 is a structural sectional view of still another embodiment of the present invention.
FIG. 6 is a structural cross-sectional view of still another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 Substrate 12 Lower electrode 13 Organic layer 14 Counter electrode 15 Isolation sealing layer 17 Dry substrate 19 Internal gap 31 Substrate 32 Lower electrode 33 Organic layer 335 Non-light emitting region 337 Light emitting region 34 Counter electrode 35 Drying flange 355 Dry substrate 357 Dry substrate 36 Isolation Sealing layer 365 Isolation sealing cover 367 Isolation sealing layer 38 Isolation rib 385 Isolation rib 387 Heat radiation rib 41 Insulating layer

Claims (3)

In organic electroluminescent equipment,
A substrate,
At least one lower electrode formed on the substrate;
A plurality of insulating layers having moisture absorption characteristics and insulating characteristics are formed on the partial surface of the lower electrode, and are crossed with the lower electrode, and further have moisture absorption characteristics on the upper surface of the insulating layer. A plurality of insulating layers provided with a dry substrate and having a light emitting region formed between the two insulating layers;
At least one organic layer comprising an organic electroluminescent launch layer and provided on the lower electrode surface of the light emitting region;
At least one counter electrode provided on the surface of the organic layer;
An organic electroluminescent device characterized by comprising: 2. The organic electroluminescent device according to claim 1 , wherein the vertical height of the insulating layer is higher than the vertical height of the organic layer. 2. The organic electroluminescent device according to claim 1 , wherein the dry substrate is continuously installed on the upper surface of the counter electrode.

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