Emissive element and display device using such element

• US 6,246,179 B1
• Filed: 11/30/1999
• Issued: 06/12/2001
• Est. Priority Date: 12/01/1998
• Status: Expired due to Term

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Yamada, Tsutomu
• Primary Examiner(s): Philogene, Haissa
• Application Number:
  US09/451,457
• Time in Patent Office: 560 Days
• Field of Search: 315/169.3, 315/169.1, 313/500, 313/503, 313/504, 313/498, 313/506, 345/76, 345/92
• US Class Current: 315/169.3
• 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

Abstract

An EL element (60) comprises an anode (61), a cathode (67), and an emissive element layer (66) interposed between the two electrodes. A TFT is connected to the anode (61) at its source electrode (33s). The peripheral portion of the anode (61) and the entire region over the TFT are covered with a planarizing insulating film (17), and a part of the exposed portion of the anode (61) is connected to the emissive element layer (66). According to the above arrangement, it is possible to prevent disconnection of the emissive element layer (66) which may be caused by an uneven surface created by the thickness of the anode (61), and to avoid formation of a short circuit between the anode (61) and the cathode (67).

Claims

1. An emissive element comprising a first electrode, an emissive element layer, a second electrode, and an insulating film wherein:

said insulating film is disposed on at least a peripheral portion of said first electrode for separating said first electrode from said emissive element layer and/or said second electrode, and said insulating film has a planarized surface.

2. The emissive element defined in claim 1, wherein:

said insulating film is formed between said first electrode and said emissive element layer.

3. The emissive element defined in claim 1, wherein:

said insulating film covers the peripheral portion of said first electrode, and includes an opening over said first electrode, said opening having an edge portion forming a slope.

4. The emissive element defined in claim 3, wherein:

said edge portion of said opening slopes at an angle of elevation between 20° and

80°

with respect to a horizontal plane of said first electrode.

5. The emissive element defined in claim 1, wherein:

said insulating film overlaps said first electrode along entire peripheral portion outlining said first electrode.

6. The emissive element defined in claim 1, wherein:

said emissive element is an electroluminescence element.

7. The emissive element defined in claim 1, wherein:

said first electrode is connected to a thin-film transistor.

8. The emissive element defined in claim 1, wherein:

said insulating film is colored.

9. The emissive element defined in claim 8, wherein:

said insulating film is colored black.

10. The emissive element defined in claim 1, wherein:

said insulating film possesses a light-shielding property and/or a light-absorbing property.

11. An emissive element, comprising a first electrode, an emissive element layer, and a second electrode, wherein:

an insulating film is disposed on at least a peripheral portion of said first electrode for separating said first electrode from said emissive element layer and/or said second electrode; and

said first electrode is connected to a thin-film transistor, and said first electrode is located in a layer over said thin-film transistor with an insulating film for interlayer isolation disposed between said first electrode and said thin-film transistor.

12. An emissive element, comprising a first electrode, an emissive element layer, and a second electrode, wherein:

an insulating film is disposed on at least a peripheral portion of said first electrode for separating said first electrode from said emissive element layer and/or said second electrode wherein;

said film possess a light-shielding property and/or a light-absorbing property; and

a thin-film transistor is connected to said first electrode and disposed in a layer below said first electrode; and

in addition to covering a peripheral portion of said first electrode, said insulating film covers a region where said thin-film transistor is formed.

13. A display device, comprising

an emissive element comprising a first electrode, an emissive element layer, a second electrode, and an insulating film, wherein:

said insulating film is disposed on at least a peripheral portion of said first electrode for separating said first electrode from said emissive element layer and/or said second electrode, and said insulating film has a planarized surface.

14. The display device defined in claim 13, wherein:

said insulating film possesses a light-shielding property and/or a light-absorbing property.

15. The display device defined in claim 13, wherein:

said insulating film covers the peripheral portion of said first electrode, and includes an opening over said first electrode, said opening having an edge portion forming a slope.

16. The display device defined in claim 15, wherein:

said edge portion of said opening slopes at an angle of elevation between 20° and

80°

with respect to a horizontal plane of said first electrode.

17. The display device defined in claim 13, wherein:

said emissive element is an electroluminescence element.

18. The display device defined in claim 13, wherein:

said first electrode is connected to a thin-film transistor.

19. The display device defined in claim 13, wherein:

said insulating film is a planarizing insulating film, and covers a peripheral portion of said first electrode.

20. The display device defined in claim 13, wherein:

said insulating film is colored.

21. The display device defined in claim 20, wherein:

said insulating film is colored black.

22. A display device, comprising an emissive element including a first electrode, an emissive element layer, and a second electrode, wherein:

an insulating film is disposed on at least a peripheral portion of said first electrode for separating said first electrode from said emissive element layer and/or said second electrode; and

said first electrode is connected to a thin-film transistor; and

said first electrode is located in a layer over said thin-film transistor with an insulating film for interlayer isolation disposed between said first electrode and said thin-film transistor.

23. A display device, comprising an emissive element including a first electrode, an emissive element layer, and a second electrode, wherein:

an insulating film is disposed on at least a peripheral portion of said first electrode for separating said first electrode form said emissive element layer and/or said second electrode; and

said insulating film possesses a light-shielding property and/or a light-absorbing property; and

a thin-film transistor is connected to said first electrode and disposed in a layer below said first electrode; and

in addition to covering a peripheral portion of said first electrode, said insulating film disposed between said first electrode and said emissive element layer covers a region where said thin-film transistor is formed.

24. An emissive element comprising a first electrode, an emissive element layer, a second electrode, an insulating film, and a planarizing insulating film, wherein:

said insulating film is disposed on at least a peripheral portion of said first electrode for separating said first electrode from said emissive element layer and/or said second electrode; and

said planarizing insulating film is disposed under said first electrode for planarizing an upper surface thereof.

25. The emissive element defined in claim 24, wherein:

said insulating film is a planarized surface.

26. The emissive element defined in claim 24, wherein:

said insulating film is formed between said first electrode and said emissive element layer.

27. The emissive element defined in claim 24, wherein:

said insulating film covers the peripheral portion of said first electrode, and includes an opening over said first electrode, said opening having an edge portion forming a slope.

28. The emissive element defined in claim 24, wherein:

said edge portion of said opening slopes at an angle of elevation between 20° and

80°

with respect to a horizontal plane of said first electrode.

29. The emissive element defined in claim 24, wherein:

said insulating film overlaps said first electrode along entire peripheral portion outlining said first electrode.

30. The emissive element defined in claim 24, wherein:

said emissive element is an electroluminescence element.

31. The emissive element defined in claim 24, wherein:

said first electrode is connected to a thin-film transistor.

32. The emissive element defined in claim 31, wherein:

said first electrode is located in a layer over said thin-film transistor with an insulating film for interlayer isolation disposed between said first electrode and said thin-film transistor.

33. The emissive element defined in claim 24, wherein:

said insulating film is colored.

34. The emissive element defined in claim 33, wherein:

said insulating film is colored black.

35. The emissive element defined in claim 24, wherein:

said insulating film possesses a light-shielding property and/or a light-absorbing property.

36. The emissive element defmed in claim 35, further comprising:

a thin-film transistor connected to said first electrode and disposed in a layer below said first electrode, wherein, in addition to covering a peripheral portion of said first electrode, said insulating film covers a region where said thin-film transistor is formed.

37. A display device comprising:

an emissive element including a first electrode, an emissive element layer, a second electrode, an insulating film, and a planarizing insulating film, wherein;

said insulating film is disposed on at least a peripheral portion of said first electrode for separating said first electrode from said emissive element layer and/or said second electrode; and

said planarizing insulating film is disposed under said first electrode.

38. The display device defined in claim 37, wherein:

said insulating film has a planarized surface.

39. The display device defined in claim 37, wherein:

said insulating film is formed between said first electrode and said emissive element layer.

40. The display device defined in claim 37, wherein:

said insulating film covers the peripheral portion of said first electrode, and includes an opening over said first electrode, said opening having an edge portion forming a slope.

41. The display device defined in claim 37, wherein:

said edge portion of said opening slopes at an angle of elevation between 20° and

80°

with respect to a horizontal plane of said first electrode.

42. The display device defined in claim 37, wherein:

said insulating film overlaps said first electrode along entire peripheral portion outlining said first electrode.

43. The display device defined in claim 37, wherein:

said emissive element is an electroluminescence element.

44. The display device defined in claim 37, wherein:

said first electrode is connected to a thin-film transistor.

45. The display device defined in claim 44, wherein:

said first electrode is located in a layer over said thin-film transistor with an insulating film for interlayer isolation disposed between said first electrode and said thin-film transistor.

46. The display device defined in claim 37, wherein:

said insulating film is colored.

47. The display device defined in claim 46, wherein:

said insulating film is colored black.

48. The display device defined in claim, 37, wherein:

said insulating film possesses a light-shielding property and/or a light-absorbing property.

49. The display device defined in claim 48, further comprising:

a thin-film transistor connected to said first electrode and disposed in a layer below said first electrode, wherein

in addition to covering a peripheral portion of said first electrode, said insulating film covers a region where said thin-film transistor is formed.