Structure to enhance light extraction and lifetime of OLED devices

• US 9,130,195 B2
• Filed: 11/22/2013
• Issued: 09/08/2015
• Est. Priority Date: 11/22/2013
• Status: Active Grant

• Current Assignee: Universal Display Corporation
• Original Assignee: Universal Display Corporation
• Inventors: Ma, Ruiqing, McGraw, Gregory, Quinn, William E., Harikrishna Mohan, Siddharth
• Primary Examiner(s): LE, DUNG ANH
• Application Number:
  US14/087,940
• Publication Number:
  US 20150144890A1
• Time in Patent Office: 655 Days
• Field of Search: 257 12- 13, 257/40, 257/81, 257/84, 257 87- 89, 257 98-100, 257347-348, 257433-434, 311/112, 311/501, 311/503, 311506-507
• US Class Current: 1/1
• CPC Class Codes: H10K 50/858 comprising refractive means, e.g. lenses

Abstract

A device having high index layers is provided. The device includes an organic light emissive device, an air interface, a first planarization layer, and a first barrier layer. The first planarization layer is disposed between the air interface and the organic light emissive device and has an index of refraction of at least 1.6. The first barrier layer is disposed between the first planarization layer and the organic emissive device and has an index of refraction of at least 1.6.

Claims

1. A device comprising:

an organic light enlitting device having a first electrode, a second electrode, and a light emitting layer disposed between the first and second electrodes;

an air interface;

a first planarization layer disposed between the air interface and the organic light emitting device, the first planarization layer having an index of refraction of at least 1.6; and

a first barrier layer disposed between the first planarization layer and the organic light emitting device, the first barrier layer having an index of refraction of at least 1.6;

wherein the first planarization layer planarizes a non-planar surface of a layer of the device.

2. The device of claim 1, wherein the device further comprises:

a substrate having a first surface and a second surface;

wherein;

the first planarization layer is disposed over the first surface of the substrate;

the first barrier layer is disposed over the first planarization layer; and

the organic light emitting device is disposed over the first barrier layer.

3. The device of claim 1, wherein the first planarization layer has an index of refraction of at least 1.7.

4. The device of claim 1, wherein the first barrier layer has an index of refraction of at least 1. 7.

5. The device of claim 2, wherein the first planarization layer is in physical contact with the substrate.

6. The device of claim 2, wherein the first barrier layer is in physical contact with the first planarization layer.

7. The device of claim 2, further comprising a light extraction layer disposed between the organic light emitting device and the air interface.

8. The device of claim 7, wherein the light extraction layer is disposed between the first surface of the substrate and the first planarization layer.

9. The device of claim 7, wherein the light extraction layer is disposed over the second surface of the substrate.

10. The device of claim 7, wherein the light extraction layer comprises a surface with topographical features.

11. The device of claim 1, further comprising at least one layer disposed between the first planarization layer and the air interface.

12. The device of claim 11, wherein the refractive index of the at least one layer disposed between the first planarization layer and the air interface is not greater than the refractive index of the first planarization layer.

13. The device of claim 1, wherein for every interface between the organic light emitting device and the air interface, the interface is defined by a first layer and a second layer, the first layer is closer to the organic light emitting device than the second layer, and the second layer has a refractive index not greater than the refractive index of the first layer.

14. The device of claim 1, wherein for every interface between the organic light emitting device and the air interface, the interface is defined by a first layer and a second layer, the first layer is closer to the organic light emitting device than the second layer, and the second layer has a refractive index not more than 0.05 greater than the refractive index of the first layer.

15. The device of claim 1, wherein for every interface between the organic light emitting device and the air interface, the interface is defined by a first layer and a second layer, the first layer is closer to the organic light emitting device than the second layer, and the second layer has a refractive index not more than 0.1 greater than the refractive index of the first layer.

16. The device of claim of claim 2, wherein the second surface of the substrate has a plurality of topographical features.

17. The device of claim 1, wherein the indices of refraction of the first planarization layer and the first barrier layer are higher than the index of refraction of the substrate.

18. The device of claim 2, further comprising a second planarization layer disposed over the first barrier layer, wherein the second planarization layer is disposed between the first barrier layer and the organic light emitting device.

19. The device of claim 18, further comprising a second barrier layer disposed over the second planarization layer, wherein the second barrier layer is disposed between the second planarization layer and the organic light emitting device.

20. The device of claim 1, wherein the substrate comprises a flexible material.

21. The device of claim 2, wherein the index of refraction of the first planarization layer is less than the index of refraction of the first barrier layer and greater than the index of refraction of the substrate.

22. The device of claim 2, wherein the first surface of the substrate has a plurality of topographical features, and the planarization layer planarizes the first surface of the substrate.