Light emitting display apparatus having plurality of structures under light emitting element
A light emitting display apparatus can include a substrate; an over coating layer disposed on the substrate; a plurality of structures on the over coating layer, each of the plurality of structures including a flat upper surface; a reflective layer disposed on the plurality of structures; and a light emitting element disposed on the plurality of structures and the reflective layer.
1. A light emitting display apparatus, comprising:
a substrate including an emission area and a non-emission area;
an over coating layer disposed on the substrate;
a plurality of structures on the over coating layer in the emission area, each of the plurality of structures including a flat upper surface;
an intermediate layer disposed between the over coating layer and the plurality of structures;
a reflective layer disposed on the plurality of structures and covering the flat upper surface of each of the plurality of structures; and
a light emitting element disposed on the plurality of structures and the reflective layer, the light emitting element including a first electrode on the reflective layer, a light emitting layer on the first electrode, and a second electrode on the light emitting layer,
wherein the plurality of structures are separated from the over coating layer,
wherein the intermediate layer is formed of a metal material, and
wherein the plurality of structures are aperiodically disposed and the plurality of structures have various sizes so that the reflective layer has an irregular concave-convex structure.
2. The light emitting display apparatus of claim 1 , wherein each of the plurality of structures has a mesa shape including a flat top surface and sloped sides.
3. The light emitting display apparatus of claim 1 , wherein an upper surface of the reflective layer has a flat shape.
4. The light emitting display apparatus of claim 1 , wherein the plurality of structures are formed of a dry-etchable material.
5. The light emitting display apparatus of claim 1 , wherein the intermediate layer is formed of a material having a different dry etching condition from a material which forms the plurality of structures.
6. The light emitting display apparatus of claim 1 , wherein an upper surface of the intermediate layer has a flat shape.
7. The light emitting display apparatus of claim 1 , wherein the plurality of structures include one of a circular trapezoidal shape or a cylindrical shape.
8. A light emitting display apparatus, comprising:
a substrate including an emission area and a non-emission area;
an over coating layer disposed on the substrate;
a light emitting element disposed on the over coating layer, the light emitting element including a first electrode, a light emitting layer on the first electrode, and a second electrode on the light emitting layer;
a reflective layer disposed between the over coating layer and the first electrode of the light emitting element;
a plurality of structures disposed between the over coating layer and the reflective layer in the emission area, the plurality of structures being spaced apart from each other and configured to enhance light extraction efficiency of the light emitting element; and
an etch stopper disposed between the over coating layer and the plurality of structures and formed of a metal material,
wherein each of the plurality of structures has a shape configured to reduce a scattering reflectance of the light emitting element and enhance a visual sense of black for the light emitting element when the light emitting element is off,
wherein the plurality of structures are separated from the over coating layer and a surface of the plurality of structures is covered with the reflective layer, and
wherein the plurality of structures are aperiodically disposed and the plurality of structures have various sizes so that the reflective layer has an irregular concave-convex structure.
9. The light emitting display apparatus of claim 8 , wherein each of the plurality of structures has a mesa shape including a flat top surface and sloped sides.
10. The light emitting display apparatus of claim 8 , wherein an upper surface of each of the plurality of structures is flat.
11. The light emitting display apparatus of claim 8 , wherein the etch stopper is configured to reduce damage of the over coating layer when the over coating layer and the plurality of structures are dry-etched using an simultaneously etchable material.
12. The light emitting display apparatus of claim 11 , wherein the etch stopper is formed of a material having a different etching ratio for dry etching than the plurality of structures, and
wherein the etch stopper has a flat upper surface.
13. The light emitting display apparatus of claim 12 , wherein the reflective layer has a flat shape over an upper surface of each of the plurality of structures and an upper surface of the etch stopper exposed by the plurality of structures, and
wherein the reflective layer is configured to maintain a micro cavity effect of the light emitting element.