ORGANIC LIGHT EMITTING DISPLAY DEVICE HAVING REFLECTION STRUCTURE AND METHOD OF MANUFACTURING ORGANIC LIGHT EMITTING DISPLAY DEVICE HAVING REFLECTION STRUCTURE

• US 20130049028A1
• Filed: 03/08/2012
• Published: 02/28/2013
• Est. Priority Date: 08/30/2011
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Mobile Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: PARK, Won-Sang, KIM, II-Nam, KIM, Min-Woo, BAEK, Soo-Min, KIM, Jae-Kyoung
• Granted Patent: US 8,975,636 B2
• Time in Patent Office: Days
• US Class Current: 257/88
• CPC Class Codes: H10K 50/813 characterised by their shape
• CPC Class Codes: H10K 50/818 Reflective anodes, e.g. ITO combined with thick metallic layers
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks

Abstract

An organic light emitting display device may include a substrate having a switching device, a first electrode including a reflection structure and being electrically connected to the switching device, a pixel defining layer disposed on the first electrode to define a luminescent region and a nonluminescent region, an organic light emitting structure disposed over the pixel defining layer, and a second electrode disposed over the organic light emitting structure. The first electrode may include the reflection structure such as a recess structure or a protrusion structure, so that the organic light emitting display device may ensure an enhanced light efficiency. Additionally, pixels of the organic light emitting display device may have improved uniformity because an opening of the pixel defining layer may have a rounded shape.

Claims

1. An organic light emitting display device comprising:

a substrate comprising a switching device;

a first electrode electrically connected to the switching device, the first electrode comprising a reflection structure;

a pixel defining layer disposed over the first electrode, the pixel defining layer defining a luminescent region and a nonluminescent region;

an organic light emitting structure disposed over the pixel defining layer; and

a second electrode disposed over the organic light emitting structure.

2. The organic light emitting display device of claim 1, wherein the reflection structure of the first electrode is configured to reflect at least part of a light generated from the organic light emitting structure and headed to the nonluminescent region toward the luminescent region.

3. The organic light emitting display device of claim 1, wherein the reflection structure comprises a recess structure and wherein the pixel defining layer comprises an opening exposing at least a portion of the first electrode in the luminescent region.

4. The organic light emitting display device claim 3, wherein the opening of the pixel defining layer comprises a rounded sidewall and wherein the organic light emitting structure is located over the exposed portion of the first electrode along a shape of the opening of the pixel defining layer.

5. The organic light emitting display device of claim 3, wherein the first electrode comprises:

a first electrode film pattern electrically connected to the switching device;

a second electrode film pattern disposed over the first electrode film pattern;

the recess structure being formed on the second electrode film pattern in the luminescent region; and

a third electrode film pattern disposed in the recess structure.

6. The organic light emitting display device of claim 5, wherein each of the first and third electrode film patterns comprises a transparent conductive material.

7. The organic light emitting display device of claim 6, wherein the second electrode film pattern comprises a reflective material.

8. The organic light emitting display device of claim 6, wherein the second electrode comprises a material same as that of at least one of the first and the third electrode film patterns.

9. The organic light emitting display device of claim 5, wherein a sidewall of the reflection structure has a first angle of inclination relative to a plane parallel to the substrate, and wherein the opening of the pixel defining layer has a second angle of inclination greater than the first angle of inclination.

10. The organic light emitting display device of claim 9, wherein a ratio between the first angle of inclination and the second angle of inclination is in a range of about 0.3:

1.0 to about 1.0;

4.0.

11. The organic light emitting display device of claim 5, wherein a ratio of a thickness of the first electrode in the nonluminescent region relative to a thickness of the pixel defining layer in the nonluminescent region is below about 1.0.

12. The organic light emitting display device of claim 1, wherein the reflection structure of the first electrode comprises a protrusion structure.

13. The organic light emitting display device of claim 12, wherein the first electrode comprises:

a first electrode film pattern electrically connected to the switching device; and

a second electrode film pattern comprising the protrusion structure which protrudes from the first electrode film pattern.

14. The organic light emitting display device of claim 13, wherein the first electrode film pattern comprises a transparent conductive material and the second electrode film pattern comprises a reflective material.

15. The organic light emitting display device of claim 14, wherein the second electrode comprises a material same as that of the second electrode film pattern.

16. The organic light emitting display device of claim 13, wherein the pixel defining layer comprises a first portion covering the second electrode film pattern and defining the luminescent region, and a second portion disposed on the first electrode film pattern and defining the nonluminescent region.

17. The organic light emitting display device of claim 16, wherein the first portion of the pixel defining layer has a rounded shape.

18. The organic light emitting display device of claim 16, wherein a ratio of a width of the first portion relative to a thickness of the first portion is above about 1.0.

19. The organic light emitting display device of claim 16, wherein a ratio of a thickness of the second portion relative to a thickness of the second electrode film pattern is equal to or smaller than about 1.0.

20. A method of manufacturing an organic light emitting display device, comprising:

forming a switching device over a substrate;

forming an insulation layer over the substrate to cover the switching device;

forming a first electrode comprising a recess structure over the insulation layer, the first electrode being electrically connected to the switching device;

forming a pixel defining layer over the insulation layer to partially expose a portion of the first electrode;

forming an organic light emitting structure over the exposed portion of the first electrode and the pixel defining layer; and

forming a second electrode over the organic light emitting structure.

21. The method of claim 20, wherein forming the first electrode comprises:

forming a first electrode film over the insulation layer;

forming a second electrode film over the first electrode layer;

forming a first electrode film pattern and a second electrode film pattern over the insulation layer by patterning the first electrode layer and the second electrode layer;

forming the recess structure on the second electrode film pattern; and

forming a third electrode film pattern in the recess structure.

22. The method of claim 21, wherein forming the recess structure comprises a dry etching process.

23. The method of claim 21, wherein the recess structure is formed while patterning the first and the second electrode layers to form the first and the second electrode film patterns.

24. The method of claim 21, wherein forming the pixel defining layer comprises forming an opening exposing at least a portion of the third electrode film pattern by partially etching the pixel defining layer.

25. A method of manufacturing an organic light emitting display device, comprising:

forming a switching device over a substrate;

forming an insulation layer over the substrate to cover the switching device;

forming a first electrode comprising a protrusion structure over the insulation layer, the first electrode being electrically connected to the switching device;

forming a pixel defining layer over the insulation layer and the first electrode;

forming an organic light emitting structure over the pixel defining layer; and

forming a second electrode over the organic light emitting structure.

26. The method of claim 25, wherein forming the first electrode comprises:

forming a first electrode film over the insulation layer;

forming a second electrode film over the first electrode film;

forming a second electrode film pattern comprising the protrusion structure by patterning the second electrode film; and

forming a first electrode film pattern over the insulation layer by patterning the first electrode film.

27. The method of claim 26, wherein the second electrode film pattern is formed while forming the first electrode film pattern.

28. The method of claim 26, wherein the pixel defining layer is formed over the first electrode film pattern to cover the second electrode film pattern.