Light emitting device and manufacturing method thereof

• US 20050133783A1
• Filed: 01/25/2005
• Published: 06/23/2005
• Est. Priority Date: 11/22/2001
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Seo, Satoshi, Yamazaki, Shunpei
• Granted Patent: US 7,282,734 B2
• Time in Patent Office: Days
• US Class Current: 257/40
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 50/80 Constructional details
• CPC Class Codes: H10K 50/805 Electrodes
• CPC Class Codes: H10K 50/81 Anodes
• CPC Class Codes: H10K 50/814 combined with auxiliary electrodes, e.g. ITO layer combined with metal lines
• CPC Class Codes: H10K 50/824 combined with auxiliary electrodes
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/17 Passive-matrix OLED displays
• CPC Class Codes: H10K 59/805 Electrodes
• CPC Class Codes: H10K 71/841 Applying alternating current [AC] during manufacturing or treatment

Abstract

A light emitting device is provided, which uses alternating current drive as a method of driving the light emitting device, and in which light emission is always obtained when voltages having different polarities are alternately applied, and a method of manufacturing the light emitting device is also provided. A first light emitting element made from an anode, an organic compound layer, and a cathode, and a second electrode made from an anode, an organic compound layer, and a cathode are formed. The light emitting elements are formed sandwiching the same organic compound layer. The anode of the first light emitting element and the anode of the second light emitting element, and the cathode of the first light emitting element and the cathode of the second light emitting element, are formed on opposite sides of the organic compound layer, respectively, thus sandwiching the organic compound layer. Note that voltages having an inverse polarity are applied alternately by the alternating current drive, and therefore light can always be emitted by any one of the first light emitting element or the second light emitting element.

Claims

1. A light emitting device comprising:

a first electrode comprising a material for an anode arranged in a stripe form;

a second electrode comprising the material for the anode arranged in a stripe form perpendicularly to the first electrode; and

a layer comprising an organic compound between the first electrode and the second electrode,

wherein a part of the first electrode and a part of the second electrode function as cathodes.

2. The light emitting device according to claim 1,

wherein the layer comprising the organic compound has bipolar characteristics.

3. The light emitting device according to claim 1,

wherein the layer comprising an organic compound comprises a material having hole transporting characteristics and a material having electron transporting characteristics.

4. The light emitting device according to claim 1,

wherein the light emitting device is one selected from the group consisting of a display device, a digital still camera, a notebook personal computer, a mobile computer, a portable image playback device provided with a recording medium, a goggle display, a video camera and a portable telephone.

5. A light emitting device comprising:

a first electrode arranged in a stripe form;

a first auxiliary electrode on a part of the first electrode;

a layer comprising an organic compound on the first electrode and the first auxiliary electrode;

a second auxiliary electrode on the layer comprising the organic compound and over another part of the first electrode; and

a second electrode arranged in a stripe form perpendicularly to the first electrode on the layer comprising the organic compound and the second auxiliary electrode.

6. The light emitting device according to claim 5,

wherein the layer comprising the organic compound has bipolar characteristics.

7. The light emitting device according to claim 5,

wherein the layer comprising the organic compound comprises a material having hole transporting characteristics and a material having electron transporting characteristics.

8. The light emitting device according to claim 5,

wherein the light emitting device is one selected from the group consisting of a display device, a digital still camera, a notebook personal computer, a mobile computer, a portable image playback device provided with a recording medium, a goggle display, a video camera and a portable telephone.

9. The light emitting device according to claim 5,

wherein the first auxiliary electrode is arranged in a stripe form perpendicularly to the first electrode.

10. The light emitting device according to claim 5,

wherein the second auxiliary electrode is arranged in a stripe form perpendicularly to the first electrode.

11. A light emitting device comprising:

a first electrode comprising a material for an anode arranged in a stripe form;

a first auxiliary electrode comprising a material for a cathode on a part of the first electrode;

a layer comprising an organic compound on the first electrode and the first auxiliary electrode;

a second auxiliary electrode comprising the material for the cathode on the layer comprising the organic compound and over another part of the first electrode; and

a second electrode comprising the material for the anode arranged in a stripe form perpendicularly to the first electrode on the layer comprising the organic compound and the second auxiliary electrode.

12. The light emitting device according to claim 11,

wherein the layer comprising the organic compound has bipolar characteristics.

13. The light emitting device according to claim 11,

Wherein the layer comprising the organic compound comprises a material having hole transporting characteristics and a material having electron transporting characteristics.

14. The light emitting device according to claim 11,

wherein the light emitting device is one selected from the group consisting of a display device, a digital still camera, a notebook personal computer, a mobile computer, a portable image playback device provided with a recording medium, a goggle display, a video camera and a portable telephone.

15. The light emitting device according to claim 11,

wherein the first auxiliary electrode is arranged in a stripe form perpendicularly to the first electrode.

16. The light emitting device according to claim 11,

wherein the second auxiliary electrode is arranged in a stripe form perpendicularly to the first electrode.

17. A light emitting device comprising:

a first electrode arranged in a stripe form;

a second electrode arranged in a stripe form perpendicularly to the first electrode; and

a layer comprising an organic compound between the first electrode and the second electrode,

wherein a first part of the first electrode in a first part of a crossover of the first electrode and the second electrode contacts with the layer comprising the organic compound,

wherein a first auxiliary electrode is interposed between a first part of the second electrode in the first part of the crossover of the first electrode and the second electrode and the layer comprising the organic compound,

wherein a second part of the second electrode in a second part of the crossover of the first electrode and the second electrode contacts with the layer comprising the organic compound,

wherein a second auxiliary electrode is interposed between a second part of the first electrode in the second part of the crossover of the first electrode and the second electrode and the layer comprising the organic compound.

18. The light emitting device according to claim 17,

wherein the layer comprising the organic compound has bipolar characteristics.

19. The light emitting device according to claim 17,

wherein the layer comprising an organic compound comprises a material having hole transporting characteristics and a material having electron transporting characteristics.

20. The light emitting device according to claim 17,

wherein the light emitting device is one selected from the group consisting of a display device, a digital still camera, a notebook personal computer, a mobile computer, a portable image playback device provided with a recording medium, a goggle display, a video camera and a portable telephone.

21. The light emitting device according to claim 17,

wherein the first auxiliary electrode is arranged in a stripe form perpendicularly to the first electrode.

22. The light emitting device according to claim 17,

wherein the second auxiliary electrode is arranged in a stripe form perpendicularly to the first electrode.