Organic EL display and manufacturing method thereof

• US 20080129194A1
• Filed: 10/25/2007
• Published: 06/05/2008
• Est. Priority Date: 10/26/2006
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: Kyocera Corporation
• Inventors: Ogawa, Hiromitsu, Abe, Shinichi, Asano, Motohiko
• Granted Patent: US 8,053,983 B2
• Time in Patent Office: Days
• US Class Current: 313/504
• CPC Class Codes: H10K 50/841 Self-supporting sealing arrangements
• CPC Class Codes: H10K 50/844 Encapsulations

Abstract

An organic EL display comprises an element substrate, an organic EL element formed on the element substrate, comprising an organic layer including a light emitting layer and a pair of electrode layers disposed on both sides of the organic layer. The organic layer comprises a first organic material. The organic EL display further comprises a capping layer comprising a second organic material having a glass transition point lower than one of the first organic material and a protective layer on the capping layer.

Claims

1. A manufacturing method of an organic EL display comprising:

preparing an organic EL element comprising an organic layer including a light emitting layer, and a pair of electrode layers disposed on both upper and lower sides of the organic layer, the organic layer comprising a first organic material;

depositing an organic material layer comprising a second organic material having a glass transition point lower than that of the first organic material, on the organic EL element;

heating the organic material layer at a temperature which is lower than the glass transition point of the first organic material and higher than that of the second organic material, to fluidize at least a part of the organic material layer;

cooling the organic material layer to a temperature which is lower than the glass transition point of the second organic material, to change the fluidized organic material layer into a capping layer by solidifying the fluidized organic material layer; and

forming a protective layer on the capping layer.

2. A manufacturing method of an organic EL display according to claim 1,

wherein, when a foreign matter is adhered to the organic EL element, a first gap is formed between the foreign matter and the organic material layer on the organic EL element before fluidizing the organic material layer.

3. A manufacturing method of an organic EL display according to claim 2,

wherein the fluidized organic material layer enters the first gap.

4. A manufacturing method of an organic EL display according to claim 2,

wherein the organic material layer comprises a first portion on the organic EL element and a second portion disposed on the foreign matter and separated from the first portion before fluidizing the organic material layer, and

wherein the second portion enters the first gap while fluidizing the organic material layer.

5. A manufacturing method of an organic EL display according to claim 1, further comprising:

forming a partition wall around the organic EL element before depositing the organic material layer,

wherein a second gap is formed between the partition wall and the organic material layer before fluidizing the organic material layer.

6. A manufacturing method of an organic EL display according to claim 5,

wherein the fluidized organic material layer enters the second gap.

7. A manufacturing method of an organic EL display according to claim 5,

wherein the organic material layer comprises a first portion on the organic EL element and a second portion disposed on the partition wall and separated from the first portion before fluidizing the organic material layer, and

wherein the second portion enters the second gap while fluidizing the organic material layer.

8. An organic EL display comprising:

an organic EL element comprising an organic layer including a light emitting layer, and a pair of electrode layers on both upper and lower sides of the organic layer, the organic layer comprising a first organic material;

a capping layer on the organic EL element, comprising a second organic material having a glass transition point lower than that of the first organic material; and

a protective layer on the capping layer;

wherein the capping layer covers at least a lower part of a first foreign matter between the organic EL element and the protective layer while an upper part of the first foreign matter is exposed from the capping layer.

10. An organic EL display according to claim 8,

wherein a difference in refractive indexes between the capping layer and the protective layer is within 0.7.

11. An organic EL display according to claim 8, further comprising:

a circuit layer configured to control light emission of the organic EL element; and

a planarizing layer covering the circuit layer;

wherein the organic EL element is formed on the planarizing layer and a part of the protective layer is formed on the planarizing layer; and

wherein the capping layer has an extended portion on the planarizing layer, the extended portion covering at least a lower part a second foreign matter between the part of the protective layer and the planarizing layer while an upper part of the second foreign matter is exposed from the extended portion.

17. An organic EL display according to claim 8,

wherein the lower part of the first foreign matter is the lower side surface thereof.

19. An organic EL display according to claim 11,

wherein the lower part of the second foreign matter is the lower side surface thereof.

9. An organic EL display comprising:

an organic EL element comprising an organic layer including a light emitting layer, and a pair of electrode layers on both upper and lower sides of the organic layer, the organic layer comprising first organic material;

a capping layer on the organic EL element, comprising second organic material having a glass transition point lower than that of the first organic material;

a protective layer on the capping layer; and

a partition wall around the organic EL element;

wherein the capping layer covers at least a lower part of the partition wall while an upper part of the partition wall exposed from the capping layer.

12. An organic EL display according to claim 9, further comprising:

a circuit layer configured to control light emission of the organic EL element; and

a planarizing layer covering the circuit layer;

wherein the organic EL element is formed on the planarizing layer and a part of the protective layer is formed on the planarizing layer; and

wherein the capping layer has an extended portion on the planarizing layer, the extended portion covering at least a lower part of a second foreign matter between the protective layer and the planarizing layer while an upper part of the second foreign matter is exposed from the extended portion.

13. An organic EL display according to claim 12, further comprising:

an element substrate comprising the circuit layer;

a cover substrate disposed on the element substrate to be opposite to the element substrate; and

a sealing material disposed between the element substrate and cover substrate, surrounding the organic EL element;

wherein the capping layer is formed inside a region surrounded by the sealing material.

14. An organic EL display according to claim 13, further comprising:

an element substrate comprising the circuit layer;

a cover substrate disposed on the element substrate to be opposite to the element substrate; and

a sealing material disposed between the element substrate and cover substrate, surrounding the organic EL element;

wherein the capping layer is formed inside a region surrounded by the sealing material.

15. An organic EL display according to claim 12, further comprising:

an element substrate comprising the circuit layer;

a cover substrate disposed on the element substrate to be opposite to the element substrate; and

a sealing material disposed between the element substrate and cover substrate, contacting the protective layer on the organic EL element.

16. An organic EL display according to claim 13, further comprising:

an element substrate comprising the circuit layer;

a cover substrate disposed on the element substrate to be opposite to the element substrate; and

a sealing material disposed between the element substrate and cover substrate, contacting the protective layer on the organic EL element.

18. An organic EL display according to claim 9,

wherein the lower part of the partition wall is the lower side surface thereof.

20. An organic EL display according to claim 12,

wherein the lower part of the second foreign matter is the lower side surface thereof.