Light emitting device and method of manufacturing the same

• US 20050073243A1
• Filed: 06/24/2003
• Published: 04/07/2005
• Est. Priority Date: 06/27/2002
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Noda, Takeshi, Yamazaki, Shunpei
• Granted Patent: US 7,663,305 B2
• Time in Patent Office: Days
• US Class Current: 313/498
• CPC Class Codes: H10K 50/818 Reflective anodes, e.g. ITO combined with thick metallic layers
• CPC Class Codes: H10K 50/824 combined with auxiliary electrodes
• CPC Class Codes: H10K 50/844 Encapsulations
• CPC Class Codes: H10K 50/865 comprising light absorbing layers, e.g. light-blocking layers
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks
• CPC Class Codes: H10K 59/126 Shielding, e.g. light-blocking means over the TFTs
• CPC Class Codes: H10K 59/80522 combined with auxiliary electrodes
• CPC Class Codes: H10K 59/8792 comprising light absorbing layers, e.g. black layers
• CPC Class Codes: H10K 71/135 using ink-jet printing

Abstract

In a top emission structure, there has been a problem in that a wiring, a TFT, or the like is provided in regions other than a light emitting region so that light reflected by the wiring reaches eyes of an observer. The present invention prevents light that is reflected by a wire from reaching eyes of an observer by providing a light-absorbing multilayer film (61) in regions other than a light emitting region. Specifically, the light-absorbing multilayer film (61) is used as an upper layer of a partition wall (also called as a bank or a barrier) that covers ends of a first electrode (66b) whereas an organic resin film (67) is used as a lower layer of the partition wall. The partition wall in the present invention is characterized by being a laminate of three or more layers formed of different materials.

Claims

1. A light emitting device comprising:

a first electrode connected to a thin film transistor over a substrate having an insulating surface;

a partition wall covering an edge of the first electrode;

a layer comprising an organic compound in contact with the first electrode; and

a second electrode in contact with the layer comprising an organic compound,

wherein the partition wall comprises a laminate of an organic resin layer and a light-absorbing multilayer film.

2. A light emitting device according to claim 1, wherein the partition wall covers other regions than a light emitting region in which the first electrode and the organic compound-containing layer are in contact with each other and laid on top of each other.

3. A light emitting device according to claim 1, wherein the light-absorbing multilayer film includes at least one layer comprising a material selected from the group consisting of Al₂O₃, SiO₂, ZrO₂, HfO₂, Sc₂O₃, TiO₂, ITO and ZnO.

4. A light emitting device according to claim 1, wherein the light-absorbing multilayer film includes at least a light-transmissive insulating film comprising nitride.

5. A light emitting device according to claim 1, wherein the light-absorbing multilayer film includes at least a layer comprising a material selected from the group consisting of Al, Cu, Au, Mo, Ni, Pt, Rh, Ag, W, Cr, Co, Si, Zr, Ta, Inconel and Nichrome.

6. A light emitting device according to claim 1, wherein the light-absorbing multilayer film is a laminate of a reflective metal film, a light transmissive insulating film comprising nitride, a metal nitride film and another light-transmissive insulating comprising nitride.

7. A light emitting device according to claim 1, wherein the light-absorbing multilayer film comprises a laminate of a metal film mainly composed of aluminum, a silicon nitride film, a titanium nitride film, and another silicon nitride film.

8. A light emitting device according to claim 1, wherein the second electrode is a conductive film transmissive of light.

9. A light emitting device according to claim 1, wherein the first electrode has a concave shape and is formed in a self-aligning manner using the partition wall as a mask.

10. A light emitting device according to claim 1, wherein the first electrode is an anode and the second electrode is a cathode.

11. A light emitting device according to claim 1, wherein the first electrode is a cathode and the second electrode is an anode.

12. A light emitting device according to claim 1, wherein the layer comprising an organic compound is made of a material emitting red light, green light, or blue light.

13. A light emitting device according to claim 1, wherein the layer comprising an organic compound comprises a material emitting white light, and is combined with a color filter provided in a sealing member.

14. A light emitting device according to claim 1, wherein the layer comprising an organic compound comprises a material emitting monochromatic light, and is combined with one of a color conversion layer and a colored layer provided in a sealing member.

15. A light emitting device according to claim 1, wherein the light emitting device is any one of a video camera, a digital camera, a goggle-type display, a car navigation system, a personal computer, a DVD player, an electronic game machine, and a portable information terminal.

16. A method of manufacturing a light emitting device with a light emitting element, the light emitting element having an anode, an organic compound-containing layer that is in contact with the anode, and a cathode that is in contact with the organic compound-containing layer, comprising:

forming a laminate of an insulating film and a light-absorbing multilayer film on a first electrode that is formed from a metal film;

selectively etching the laminate of the insulating film and the light-absorbing multilayer film to form a partition wall that covers ends of the first electrode;

forming an organic compound-containing film; and

forming on the organic compound-containing film a second electrode from a metal thin film that transmits light.

17. A method of manufacturing a light emitting device according to claim 16, wherein the insulating film comprises an inorganic insulating film or an organic resin film.

18. A method of manufacturing a light emitting device according to claim 16, wherein the first electrode is an anode and comprises a metal layer that is larger in work function than the second electrode.

19. A method of manufacturing a light emitting device according to claim 16, wherein the light-absorbing multiplayer film includes at least a layer comprising a reflective metal film.

20. A method of manufacturing a light emitting device according to claim 16, wherein the light-absorbing multilayer film includes at least a layer comprising a material selected from the group consisting of Al₂O₃, SiO₂, ZrO₂, HfO₂, Sc₂O₃, TiO₂, ITO and ZnO.

21. A method of manufacturing a light emitting device according to claim 16, wherein the light-absorbing multilayer film includes at least a light-transmissive insulating film comprising nitride.

22. A method of manufacturing a light emitting device according to claim 16 wherein the light-absorbing multilayer film includes at least a layer comprising a material selected from the group consisting of Ti, Al, Cu, Au, Mo, Ni, Pt, Rh, Ag, W, Cr, Co, Si, Zr, Ta, Inconel and Nichrome.