EL display device

• US 6,593,691 B2
• Filed: 12/11/2000
• Issued: 07/15/2003
• Est. Priority Date: 12/15/1999
• Status: Expired due to Term

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Nishi, Takeshi, Ishimaru, Noriko
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): TRAN, THUY V
• Application Number:
  US09/735,096
• Publication Number:
  US 20010004190A1
• Time in Patent Office: 946 Days
• Field of Search: 313/506, 313/505, 313/311, 313/483, 313/306, 313/307, 313/310, 313/346.R, 315/169.6, 315/167
• US Class Current: 313/506
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 50/814 combined with auxiliary electrodes, e.g. ITO layer combined with metal lines
• CPC Class Codes: H10K 50/86 Arrangements for improving contrast, e.g. preventing reflection of ambient light
• CPC Class Codes: H10K 50/865 comprising light absorbing layers, e.g. light-blocking layers
• 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 59/123 Connection of the pixel electrodes to the thin film transistors [TFT]

Abstract

An EL display device capable of reducing an average film resistance of an anode in an EL device as well as displaying an image with high definition, and electrical equipment including such an EL display device are provided. A light-shielding metal film (109) is provided on an anode (108) so as to conceal gaps between the pixels. Thus, an average film resistance of the anode (108) in the EL device is reduced. Furthermore, light leakage from the gaps between the pixels can be prevented, resulting in an image display with high definition.

Claims

1. An EL display device comprising:

an active-matrix substrate over which pixels are arranged, each of said pixels having a pixel electrode electrically connected to a thin-film transistor; and

an EL element comprising said pixel electrode as a cathode, an EL layer, and an anode,

wherein a metal film is provided in contact with said anode so as to conceal edges of said pixels and gaps between said pixels.

2. An EL display device according to claim 1, wherein a film resistance of said metal film is lower than a film resistance of said anode.

3. An EL display device according to claim 1, wherein said metal film functions as a light-shielding film.

4. An EL display device according to claim 1, wherein said metal film has a layered structure.

5. An EL display device according to claim 1, wherein raised portions are provided on a surface of said cathode of said EL element.

6. An EL display device according to claim 1, wherein an element of said metal film is one selected from a group consisting of Ti, Al, Ta, W, Cr, Cu, and Ag.

7. An EL display device according to claim 1, wherein said anode comprises indium tin oxide.

8. An EL display device according to claim 1, wherein said cathode comprises aluminum.

9. An EL display device according to claim 1, wherein said EL display device is incorporated in one selected from a group consisting of a video camera, a head-mount display, an image reproduction apparatus, a portable computer, a personal computer, a car navigation system, a mobile telephone, and a car audio equipment.

10. An EL display device comprising:

an active-matrix substrate over which pixels are arranged, each of said pixels having a pixel electrode electrically connected to a thin-film transistor; and

an EL element comprising said pixel electrode as a cathode, an EL layer, and an anode,

wherein a metal film is provided between said anode and a counter substrate so as to conceal edges of said pixels and gaps between said pixels.

11. An EL display device according to claim 10, wherein a film resistance of said metal film is lower than a film resistance of said anode.

12. An EL display device according to claim 10, wherein said metal film functions as a light-shielding film.

13. An EL display device according to claim 10, wherein said metal film has a layered structure.

14. An EL display device according to claim 10, wherein raised portions are provided on a surface of said cathode of said EL element.

15. An EL display device according to claim 10, wherein an element of said metal film is one selected from a group consisting of Ti, Al, Ta, W, Cr, Cu, and Ag.

16. An EL display device according to claim 10, wherein said anode comprises indium tin oxide.

17. An EL display device according to claim 10, wherein said cathode comprises aluminum.

18. An EL display device according to claim 10, wherein said EL display device is incorporated in one selected from the group consisting of a video camera, a head-mount display, an image reproduction apparatus, a portable computer, a personal computer, a car navigation system, a mobile telephone, and a car audio equipment.

19. An EL display device comprising:

an active-matrix substrate over which pixels are arranged, each of said pixels having a pixel electrode electrically connected to a thin-film transistor; and

an EL element comprising said pixel electrode as a cathode, an EL layer, and an anode,

wherein a metal film is provided in contact with a portion of said anode so as to conceal gaps between said pixel electrodes.

20. An EL display device according to claim 19, wherein a film resistance of said metal film is lower than a film resistance of said anode.

21. An EL display device according to claim 19, wherein said metal film functions as a light-shielding film.

22. An EL display device according to claim 19, wherein said metal film has a layered structure.

23. An EL display device according to claim 19, wherein raised portions are provided on a surface of said cathode of said EL element.

24. An EL display device according to claim 19, wherein an element of said metal film is one selected from a group consisting of Ti, Al, Ta, W, Cr, Cu, and Ag.

25. An EL display device according to claim 19, wherein said anode comprises indium tin oxide.

26. An EL display device according to claim 19, wherein said cathode comprises aluminum.

27. An EL display device according to claim 19, wherein said EL display device is incorporated in one selected from a group consisting of a video camera, a head-mount display, an image reproduction apparatus, a portable computer, a personal computer, a car navigation system, a mobile telephone, and a car audio equipment.

28. An EL display device comprising:

an active-matrix substrate over which pixels are arranged, each of said pixels having a pixel electrode electrically connected to a thin-film transistor; and

an EL element comprising said pixel electrode as a cathode, an EL layer, and an anode,

wherein a metal film is provided between a portion of said anode and a counter substrate so as to conceal gaps between said pixel electrodes.

29. An EL display device according to claim 28, wherein a film resistance of said metal film is lower than a film resistance of said anode.

30. An EL display device according to claim 28, wherein said metal film functions as a light-shielding film.

31. An EL display device according to claim 28, wherein said metal film has a layered structure.

32. An EL display device according to claim 28, wherein raised portions are provided on a surface of said cathode of said EL element.

33. An EL display device according to claim 28, wherein an element of said metal film is one selected from a group consisting of Ti, Al, Ta, W, Cr, Cu, and Ag.

34. An EL display device according to claim 28, wherein said anode comprises indium tin oxide.

35. An EL display device according to claim 28, wherein said cathode comprises aluminum.

36. An EL display device according to claim 28, wherein said EL display device is incorporated in one selected from a group consisting of a video camera, a head-mount display, an image reproduction apparatus, a portable computer, a personal computer, a car navigation system, a mobile telephone, and a car audio equipment.

37. An EL display device comprising:

a thin film transistor formed over a substrate;

an EL element comprising a cathode and an anode with an EL layer interposed therebetween, said EL element electrically connected to said thin film transistor; and

a metal film in contact with said anode, said metal film provided so as to be overlapped with

a portion of said cathode.

38. An EL display device according to claim 37, wherein a film resistance of said metal film is lower than a film resistance of said anode.

39. An EL display device according to claim 37, wherein said metal film functions as a light-shielding film.

40. An EL display device according to claim 37, wherein said metal film has a layered structure.

41. An EL display device according to claim 37, wherein raised portions are provided on a surface of said cathode of said EL element.

42. An EL display device according to claim 37, wherein an element of said metal film is one selected from a group consisting of Ti, Al, Ta, W, Cr, Cu, and Ag.

43. An EL display device according to claim 37, wherein said anode comprises indium tin oxide.

44. An EL display device according to claim 37, wherein said cathode comprises aluminum.

45. An EL display device according to claim 37, wherein said EL display device is incorporated in one selected from a group consisting of a video camera, a head-mount display, an image reproduction apparatus, a portable computer, a personal computer, a car navigation system, a mobile telephone, and a car audio equipment.

46. An EL display device comprising:

a thin film transistor formed over a substrate;

an EL element comprising a cathode and an anode with an EL layer interposed therebetween, said EL element electrically connected to said thin film transistor; and

a metal film in contact with a portion of said anode, said metal film provided so as to be overlapped with a portion of said cathode.

47. An EL display device according to claim 46, wherein a film resistance of said metal film is lower than a film resistance of said anode.

48. An EL display device according to claim 46, wherein said metal film functions as a light-shielding film.

49. An EL display device according to claim 46, wherein said metal film has a layered structure.

50. An EL display device according to claim 46, wherein raised portions are provided on a surface of said cathode of said EL element.

51. An EL display device according to claim 46, wherein an element of said metal film is one selected from a group consisting of Ti, Al, Ta, W, Cr, Cu, and Ag.

52. An EL display device according to claim 46, wherein said anode comprises indium tin oxide.

53. An EL display device according to claim 46, wherein said cathode comprises aluminum.

54. An EL display device according to claim 46, wherein said EL display device is incorporated in one selected from a group consisting of a video camera, a head-mount display, an image reproduction apparatus, a portable computer, a personal computer, a car navigation system, a mobile telephone, and a car audio equipment.