Organic electroluminescent device and method for fabricating the same
View Patent ↗An organic EL device based on top emission and a method for fabricating the same are disclosed. The organic EL device includes a substrate, a thin film transistor (TFT) formed on the substrate, a planarization film formed on the entire surface of the substrate including the TFT, a first electrode formed on the planarization film, having a surface at a corner area higher than a surface at a center area, an organic EL layer formed on the first electrode, and a second electrode formed on the organic EL layer.
1. A method for fabricating an organic EL device comprising the steps of:
forming a TFT on a substrate;
forming a planarization film on the entire surface of the substrate including the TFT;
forming a first electrode having a concave shaped surface by forming a metal material having tensile stress on the planarization film and patterning the metal material, forming at least a second layer including one of a resistance reducing film and a reflecting film, and floating a corner portion of the first electrode from the surface of the planarization film by tensile stress of the first electrode;
forming an organic EL layer on the first electrode; and
forming a second electrode on the organic EL layer,
wherein the forming of the first electrode includes: forming a metal material having tensile stress on the planarization film at a temperature of 200° C., forming a mask film on the metal material and patterning the mask film, removing the metal material using the patterned mask film as a mask, and forming the first electrode having a concave shaped surface by removing the mask film remaining on the metal material, wherein the metal material includes at least one of Al, Au, Mo, Ti, and Ag, and an alloy thereof.
2. The method according to claim 1 , wherein the mask film is a photoresist.
3. The method according to claim 1 , wherein the first electrode is an anode, and the second electrode is a cathode.
4. The method according to claim 1 , wherein the tensile stress of the metal material is controlled by varying at least one or more of pressure, power, the distance between a target and the substrate, temperature, bias applied to the substrate, type of the substrate, deposition material, when the first electrode is formed.
5. The method according to claim 1 , wherein the first electrode is formed using at least one of E-beam and sputtering.