Light emitting device and method of manufacturing the same

• US 8,927,979 B2
• Filed: 05/31/2013
• Issued: 01/06/2015
• Est. Priority Date: 07/05/2002
• Status: Expired due to Term

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Nishi, Takeshi, Nakamura, Yasuo
• Primary Examiner(s): PERT, EVAN T
• Application Number:
  US13/906,577
• Publication Number:
  US 20130256714A1
• Time in Patent Office: 585 Days
• Field of Search: 257/40, 257/100, 438/118
• US Class Current: 257/40
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 2102/3031 Two-side emission, e.g. transparent OLEDs [TOLED]
• CPC Class Codes: H10K 50/82 Cathodes
• CPC Class Codes: H10K 50/84 Passivation; Containers; Encapsulations
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 50/844 Encapsulations
• CPC Class Codes: H10K 59/00 Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]
• CPC Class Codes: H10K 59/8722 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 71/50 Forming devices by joining two substrates together, e.g. lamination techniques

Abstract

A light emitting device having a structure in which oxygen and moisture are prevented from reaching light emitting elements, and a method of manufacturing the same, are provided. Further, the light emitting elements are sealed by using a small number of process steps, without enclosing a drying agent. The present invention has a top surface emission structure. A substrate on which the light emitting elements are formed is bonded to a transparent sealing substrate. The structure is one in which a transparent second sealing material covers the entire surface of a pixel region when bonding the two substrates, and a first sealing material (having a higher viscosity than the second sealing material), which contains a gap material (filler, fine particles, or the like) for protecting a gap between the two substrates, surrounds the pixel region. The two substrates are sealed by the first sealing material and the second sealing material. Further, reaction between electrodes of the light emitting elements (cathodes or anodes) and the sealing materials can be prevented by covering the electrodes with a transparent protective layer, for example, CaF₂, MgF₂, or BaF₂.

Claims

1. A light emitting device comprising:

a first substrate;

a plurality of light emitting elements over the first substrate, the plurality of light emitting elements each comprising;

a first electrode;

a layer comprising an organic compound over the first electrode; and

a second electrode over the layer comprising the organic compound;

a second substrate having a color filter over the first substrate and the plurality of light emitting elements,

a first sealing material interposed between the first and second substrates and disposed surrounding the plurality of light emitting elements; and

a second sealing material in contact with the first sealing material and covering the plurality of light emitting elements,

wherein the first and second sealing materials are different from each other, and

wherein light emitted from the plurality of light emitting elements passes through the second sealing material and the second substrate.

2. The light emitting device according to claim 1, wherein the first sealing material contains a gap material that maintains a gap between the first and second substrates.

3. The light emitting device according to claim 1, wherein the second sealing material has higher transparency than the first sealing material.

4. The light emitting device according to claim 1, further comprising a protective layer between the plurality of light emitting elements and the second sealing material.

5. The light emitting device according to claim 1, wherein the light emitting device is incorporated in at least one selected from the group consisting of a video camera, a digital camera, a goggle-type display, a navigation system, a personal computer, a DVD player, an electronic play equipment, and a portable information terminal.

6. A light emitting device comprising:

a first substrate;

an insulating layer over the first substrate;

a plurality of light emitting elements on the insulating layer, each light emitting element comprising;

a first electrode having a concave portion on the insulating layer;

a light emitting layer over the first electrode; and

a second electrode over the light emitting layer;

a second substrate over the first substrate and the plurality of light emitting elements;

a first sealing material interposed between the first and second substrates and disposed outside the plurality of light emitting elements; and

a second sealing material being in contact with the first sealing material and covering the plurality of light emitting elements,

wherein the first and second sealing materials are different from each other.

7. The light emitting device according to claim 6, further comprising a contact region connecting the second electrode and a wiring, wherein the contact region is covered with the second sealing material.

8. The light emitting device according to claim 6, wherein the first sealing material contains a gap material that maintains a gap between the first and second substrates.

9. The light emitting device according to claim 6, wherein the second sealing material has higher transparency than the first sealing material.

10. The light emitting device according to claim 6, further comprising a protective layer between the plurality of light emitting elements and the second sealing material.

11. The light emitting device according to claim 6, wherein light emitted from the plurality of light emitting elements passes through the second sealing material and the second substrate.

12. The light emitting device according to claim 6, wherein light emitted from the plurality of light emitting elements passes through the second sealing material and the second substrate, and through the first substrate.

13. The light emitting device according to claim 6, wherein the light emitting device is incorporated in at least one selected from the group consisting of a video camera, a digital camera, a goggle-type display, a navigation system, a personal computer, a DVD player, an electronic play equipment, and a portable information terminal.

14. A light emitting device comprising:

a first substrate;

an insulating layer over the first substrate;

a plurality of light emitting elements on the insulating layer, each light emitting element comprising;

a first electrode on the insulating layer, end portions of the first electrode being thicker than a center portion of the first electrode;

a light emitting layer over the first electrode; and

a second electrode over the light emitting layer;

a second substrate having a color filter over the first substrate and the plurality of light emitting elements;

a first sealing material interposed between the first and second substrates and disposed outside the plurality of light emitting elements; and

a second sealing material being in contact with the first sealing material and covering the plurality of light emitting elements,

wherein the first and second sealing materials are different from each other.

15. The light emitting device according to claim 14, further comprising a driver circuit portion over the first substrate, the driver circuit portion covered with the second sealing material.

16. The light emitting device according to claim 14, wherein the first sealing material contains a gap material that maintains a gap between the first and second substrates.

17. The light emitting device according to claim 14, wherein the second sealing material has higher transparency than the first sealing material.

18. The light emitting device according to claim 14, further comprising a protective layer between the plurality of light emitting elements and the second sealing material.

19. The light emitting device according to claim 14, wherein light emitted from the plurality of light emitting elements passes through the second sealing material and the second substrate.

20. The light emitting device according to claim 14, wherein the light emitting device is incorporated in at least one selected from the group consisting of a video camera, a digital camera, a goggle-type display, a navigation system, a personal computer, a DVD player, an electronic play equipment, and a portable information terminal.