ORGANIC LIGHT EMITTING DISPLAY DEVICE AND METHOD OF FABRICATING THE SAME

• US 20080150419A1
• Filed: 10/22/2007
• Published: 06/26/2008
• Est. Priority Date: 12/20/2006
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung SDI Company Limited
• Inventors: Kang, Tae-Wook
• Granted Patent: US 7,893,614 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 50/8428 Vertical spacers, e.g. arranged between the sealing arrangement and the OLED
• CPC Class Codes: H10K 50/846 comprising getter material or desiccants
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks
• CPC Class Codes: H10K 59/8723 Vertical spacers, e.g. arranged between the sealing arrangement and the OLED
• CPC Class Codes: H10K 59/874 including getter material or desiccant

Abstract

Disclosed is an organic light emitting display device (OLED). The OLED includes a substrate, an array of pixels, each pixel including a first electrode, an organic layer having an emission layer and a second electrode, an encapsulation substrate, a moisture absorbent layer and a spacer. The moisture absorbent layer is disposed in a predetermined region of the encapsulation substrate, and the spacer is disposed on the moisture absorbent layer. The spacer is formed on the encapsulation substrate or the moisture absorbent layer using a laser induced thermal imaging (LITI) process.

Claims

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

a base substrate;

an array of a plurality of organic light emitting pixels formed on the base substrate;

an encapsulation substrate opposing the base substrate, wherein the array is interposed between the base substrate and the encapsulation substrate;

a moisture absorbent layer formed on the encapsulation substrate and comprising a surface facing the array; and

a spacer disposed between the moisture absorbent layer and the array, wherein the spacer contacts a selected portion but not all of the surface of the moisture absorbent layer.

2. The OLED according to claim 1, further comprising a thin film transistor (TFT) which comprises a semiconductor layer, a gate electrode, and source and drain electrodes.

3. The OLED according to claim 1, further comprising an alignment key disposed on the encapsulation substrate.

4. The OLED according to claim 1, wherein the spacer is formed of an organic material.

5. The OLED according to claim 1, wherein the spacer is formed of an inorganic material.

6. The OLED according to claim 1, wherein the spacer contacts a non-emissive surface of the array.

7. The OLED according to claim 6, wherein the non-emissive surface is interposed between immediately neighboring emissive surfaces of the array.

8. The OLED according to claim 7, wherein the spacer contacts the surface of the moisture absorbent layer at a location that is on an imaginary line perpendicular to the surface of the moisture absorbent layer and passing a point on the non-emissive surface.

9. The OLED according to claim 1, further comprising a seal interposed between and interconnecting the base substrate and the encapsulation substrate, wherein the seal comprises a projection on a surface thereof facing the encapsulation substrate, wherein the encapsulation substrate comprises a groove formed on a surface facing the base substrate and receiving the projection of the seal.

10. A method of fabricating an OLED, comprising:

providing a base substrate and an array of a plurality of organic light emitting pixels formed on the base substrate, wherein the array comprises a plurality of emissive surfaces and a plurality of non-emissive surfaces, wherein one of the non-emissive surfaces interposed between two neighboring emissive surfaces;

providing an encapsulation substrate with a moisture absorbent layer and a spacer, wherein the moisture absorbent layer is formed on the encapsulation substrate, and wherein a spacer is formed on the moisture absorbent layer; and

arranging and interconnecting the encapsulation substrate and the base substrate such that the spacer contacts the moisture absorbent layer and is interposed between the array and the moisture absorbent layer.

11. The method according to claim 10, further comprising forming a TFT on the base substrate, the TFT comprising a semiconductor layer, a gate electrode, and source and drain electrodes.

12. The method according to claim 10, wherein the encapsulation substrate comprises an alignment key.

13. The method according to claim 10, wherein the spacer is formed on the moisture absorbent layer by using a laser induced thermal imaging (LITI) process.

14. The method according to claim 13, wherein the LITI process comprises:

providing a donor substrate comprising a base layer, a light-to-heat conversion (LHC) layer and a transfer layer formed of a spacer, wherein the a light-to-heat conversion (LHC) layer is interposed between the base layer and the transfer layer;

bonding the donor substrate to the moisture absorbent layer formed on the encapsulation substrate; and

irradiating laser beams on a selective region of the donor substrate so as to transfer a portion of the transfer layer and form the spacer.

15. The method according to claim 10, wherein the spacer forming material layer comprises an organic material.

16. The method according to claim 10, wherein the spacer forming material layer comprises an inorganic material.

17. The method according to claim 10, wherein the spacer contacts a non-emissive surface of the array.

18. An organic light emitting display device comprising:

a first substrate;

a second substrate opposing the first substrate;

an array of organic light emitting pixels interposed between the first and second substrates;

a desiccant layer formed on the second substrate; and

a spacer interposed between the array and the desiccant layer, wherein the spacer contacts both the array and the desiccant layer,

wherein the array comprises a plurality of emissive surfaces and a plurality of non-emissive surfaces, and wherein one of the non-emissive surfaces interposed between two neighboring emissive surfaces, wherein the spacer contacts one of the plurality of non-emissive surfaces of the array.

19. A method of making the organic light emitting device of claim 18, which comprises:

providing the first substrate and the array formed on the first substrate;

providing the second substrate, a desiccant layer and a spacer, wherein the desiccant layer is formed on the second substrate, wherein the spacer is formed on a portion of the desiccant layer such that the portion of the desiccant layer is interposed between the second substrate and the spacer; and

arranging the first substrate and the second substrate such that the spacer contacts the array.

20. The method of claim 19, wherein the spacer is formed on the desiccant layer by using a LITI process.