Electro-optical device and electronic device

• US 9,368,680 B2
• Filed: 08/02/2012
• Issued: 06/14/2016
• Est. Priority Date: 06/04/1999
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei, Koyama, Jun, Yamamoto, Kunitaka, Konuma, Toshimitsu
• Primary Examiner(s): GEBREMARIAM, SAMUEL A
• Application Number:
  US13/565,226
• Publication Number:
  US 20120299471A1
• Time in Patent Office: 1,412 Days
• Field of Search: 257/59, 257/72, 257/344
• US Class Current: 1/1
• CPC Class Codes: H01L 27/1218 with a particular composition or structure of the substrate
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 29/42384 for thin film field effect transistors, e.g. characterised by the thickness or the shape of the insulator or the dimensions, the shape or the lay-out of the conductor
• CPC Class Codes: H01L 29/78621 with LDD structure or an extension or an offset region or characterised by the doping profile
• CPC Class Codes: H01L 29/78627 with a significant overlap between the lightly doped drain and the gate electrode, e.g. GOLDD
• CPC Class Codes: H01L 29/78645 with multiple gate
• CPC Class Codes: H01L 29/78696 characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel H01L29/78612 takes precedence; transistors having a drain offset region or a lightly doped drain [LDD] H01L29/78621
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 50/84 Passivation; Containers; Encapsulations
• CPC Class Codes: H10K 50/841 Self-supporting sealing arrangements
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 50/846 comprising getter material or desiccants
• CPC Class Codes: H10K 50/87 Arrangements for heating or cooling
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/1213 the pixel elements being TFTs
• CPC Class Codes: H10K 59/123 Connection of the pixel electrodes to the thin film transistors [TFT]
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]

Abstract

An object of the present invention is to provide an EL display device having a high operation performance and reliability.

The switching TFT 201 formed within a pixel has a multi-gate structure, which is a structure which imposes an importance on reduction of OFF current value. Further, the current control TFT 202 has a channel width wider than that of the switching TFT to make a structure appropriate for flowing electric current. Moreover, the LDD region 33 of the current control TFT 202 is formed so as to overlap a portion of the gate electrode 35 to make a structure which imposes importance on prevention of hot carrier injection and reduction of OFF current value.

Claims

1. A light emitting device comprising:

a plastic substrate;

a thin film transistor comprising a semiconductor film over the plastic substrate, a gate insulating film over the semiconductor film, and a gate electrode over the semiconductor film;

an insulating film over the thin film transistor;

a light emitting element over the insulating film, the light emitting element comprising;

a first electrode over the plastic substrate;

an emitting layer over the first electrode, the emitting layer including an organic material; and

a second electrode over the emitting layer;

a passivation film over the light emitting element, the passivation film comprising an aluminum oxide; and

a resin film over the passivation film,

wherein light emitted from the light emitting element is emitted in a direction opposite to the plastic substrate, and

wherein the thin film transistor is electrically connected to the light emitting element.

2. The light emitting device according to claim 1, wherein the second electrode is an anode of the light emitting element.

3. The light emitting device according to claim 1, wherein the passivation film possesses a heat radiation effect.

4. The light emitting device according to claim 1, wherein the emitting layer comprises phosphorescence material.

5. The light emitting device according to claim 1, further comprising a protecting electrode between the passivation film and the second electrode.

6. The light emitting device according to claim 1, wherein the thin film transistor is an n channel transistor.

7. A semiconductor device comprising the light emitting device of claim 1, wherein the semiconductor device is at least one member selected from a group consisting of a video camera, a digital camera, a goggle type display, a car navigation system, a personal computer, and a portable information terminal.

8. The light emitting device according to claim 1, wherein the insulating film is a leveling film.

9. The light emitting device according to claim 1, wherein the resin film has an irregular shape.

10. The light emitting device according to claim 1, further comprising, a silicon nitride film between the plastic substrate and the semiconductor film.

11. A light emitting device comprising:

a plastic substrate;

a thin film transistor comprising a semiconductor film over the plastic substrate, a gate insulating film over the semiconductor film, and a gate electrode over the semiconductor film;

an insulating film over the thin film transistor, the insulating film comprising a resin material;

a light emitting element over the insulating film, the light emitting element comprising;

a first electrode;

an emitting layer over the first electrode, the emitting layer including an organic material; and

a second electrode over the emitting layer;

a passivation film over the light emitting element, the passivation film comprising aluminum oxide; and

a resin film over the passivation film,

wherein light emitted from the light emitting element is emitted in a direction opposite to the plastic substrate, and

wherein the thin film transistor is electrically connected to the light emitting element.

12. The light emitting device according to claim 11, wherein the second electrode is an anode of the light emitting element.

13. The light emitting device according to claim 11, wherein the passivation film possesses a heat radiation effect.

14. The light emitting device according to claim 11, wherein the emitting layer comprises phosphorescence material.

15. The light emitting device according to claim 11, further comprising a protecting electrode between the passivation film and the second electrode.

16. The light emitting device according to claim 11, wherein the thin film transistor is an n channel transistor.

17. A semiconductor device comprising the light emitting device of claim 11, wherein the semiconductor device is at least one member selected from a group consisting of a video camera, a digital camera, a goggle type display, a car navigation system, a personal computer, and a portable information terminal.

18. The light emitting device according to claim 11, wherein the insulating film is a leveling film.

19. The light emitting device according to claim 11, wherein the resin film has an irregular shape.

20. The light emitting device according to claim 11, further comprising, a silicon nitride film between the plastic substrate and the semiconductor film.

21. A light emitting device comprising:

a plastic substrate;

a thin film transistor comprising a semiconductor film over the plastic substrate, a gate insulating film over the semiconductor film, and a gate electrode over the semiconductor film;

an insulating film over the thin film transistor, the insulating film comprising a resin material;

a light emitting element over the thin film transistor and the insulating film, the light emitting element comprising;

a first electrode;

an emitting layer over the first electrode, the emitting layer including an organic material; and

a second electrode over the emitting layer;

a first passivation film over the light emitting element, the first passivation film comprising aluminum oxide;

a second passivation film over the first passivation film, the second passivation film comprising a resin material; and

a resin film over the second passivation film,

wherein light emitted from the light emitting element is emitted in a direction opposite to the plastic substrate, and

wherein the thin film transistor is electrically connected the light emitting element.

22. The light emitting device according to claim 21, wherein the first electrode is an anode.

23. The light emitting device according to claim 21, wherein the first passivation film possesses a heat radiation effect.

24. The light emitting device according to claim 21, wherein the emitting layer comprises phosphorescence material.

25. The light emitting device according to claim 21, further comprising a protecting electrode between the first passivation film and the second electrode.

26. The light emitting device according to claim 21, wherein the thin film transistor is an n channel transistor.

27. A semiconductor device comprising the light emitting device of claim 21, wherein the semiconductor device is at least one member selected from a group consisting of a video camera, a digital camera, a goggle type display, a car navigation system, a personal computer, and a portable information terminal.

28. The light emitting device according to claim 21, wherein the insulating film is a leveling film.

29. The light emitting device according to claim 21, wherein the resin film has an irregular shape.

30. The light emitting device according to claim 21, further comprising, a silicon nitride film between the plastic substrate and the semiconductor film.