Organic light emitting diode display and method for manufacturing the same

1. An organic light emitting diode (OLED) display comprising:

a substrate member including a plurality of pixel areas;

a thin film transistor (TFT) including a gate electrode, a source electrode, and a drain electrode and formed on the substrate member;

a planarization layer formed on the TFT and having a contact hole through which the drain electrode is partially exposed;

a pixel electrode formed on the planarization layer, and connected to the drain electrode of the TFT through the contact hole;

an organic emission layer formed on the pixel electrode;

a common power line formed over the substrate member and at least partially covered by the planarization layer;

a common electrode formed on the organic emission layer and comprising a plurality of curved portions at least two of which are formed substantially directly above the common power line;

a pixel defining layer formed on the planarization layer and having a through opening; and

a light scattering spacer formed on the pixel defining layer, wherein the light scattering spacer comprises a plurality of sub-spacers formed in each of the pixel areas and extending from the pixel defining layer, and wherein the sub-spacers are adjacent to and separated from each other by the curved portions of the common electrode.

2. The OLED display of claim 1 , further comprising a conductive layer that is formed on the same layer as at least one of the gate electrode, the source electrode, and the pixel electrode with a same material thereof, and at least a part of the conductive layer is disposed under the light scattering spacer.

3. The OLED display of claim 2 , wherein the light scattering spacer is shaped as at least one of a frustum of a pyramid, a prism, a truncated circular cone, a cylinder, a hemisphere, and a hemispheroid.

4. The OLED display of claim 2 , wherein the sub-spacers are irregularly disposed in each pixel area.

5. The OLED display of claim 2 , wherein each pixel area includes one pixel electrode and a plurality of light scattering spacers, and wherein a ratio of the entire bottom dimension of the sub-spacers to each pixel area is greater than 30% of a ratio of an area of the pixel defining layer to the pixel area.

6. The OLED display of claim 5 , wherein a bottom dimension of one sub-spacer is in a range between 1% to 20% of the ratio of the area of the pixel defining layer to the pixel area.

7. The OLED display of claim 1 , further comprising a sealing member disposed facing the substrate member with the thin film transistor interposed therebetween, wherein the light scattering spacer maintains a distance between the substrate member and the sealing member.

8. The OLED display of claim 7 , wherein the light scattering spacer is integrally formed with the pixel defining layer with a same material as the pixel defining layer.

9. The OLED display of claim 1 , wherein at least two of the sub-spacers are located substantially directly above the common power line.

10. A manufacturing method of an organic light emitting diode (OLED) display, comprising:

forming a thin film transistor (TFT) that includes a gate electrode, a source electrode, and a drain electrode on a substrate member that includes a plurality of pixel areas;

forming a planarization layer that covers the TFT and has a contact hole through which the drain electrode is partially exposed;

forming a pixel electrode connected to the drain electrode of the TFT through the contact hole on the planarization layer;

forming an organic emission layer on the pixel electrode;

forming a common power line over the substrate member to be at least partially covered by the planarization layer;

forming a common electrode on the organic emission layer, wherein the common electrode comprises a plurality of curved portions at least two of which are formed substantially directly above the common power line;

coating a photo-sensitive material layer on the planarization layer and the pixel electrode; and

forming a pixel defining layer by patterning the photo-sensitive material layer with a photolithography process using a mask on the planarization layer and simultaneously forming a light scattering spacer on the pixel defining layer, the pixel defining layer having an opening through which the pixel electrode is exposed, wherein light scattering spacer comprises a plurality of sub-spacers formed in each of the pixel areas and extending from the pixel defining layer, and wherein the sub-spacers are adjacent to and separated from each other by the curved portions of the common electrode.

11. The manufacturing method of claim 10 , wherein the photolithography process comprises a half-tone exposure process.

12. The manufacturing method of claim 10 wherein the light scattering spacer is shaped as at least one of a frustum of a pyramid, a prism, a truncated circular cone, a cylinder, a hemisphere, and a hemispheroid.

13. The manufacturing method of claim 10 , wherein at least two of the sub-spacers are located substantially directly above the common power line.