Liquid crystal display device

• US 20030164910A1
• Filed: 02/28/2003
• Published: 09/04/2003
• Est. Priority Date: 03/01/2002
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Eguchi, Shingo, Shionoiri, Yutaka, Yamazaki, Shunpei, Fujimoto, Etsuko
• Granted Patent: US 7,053,969 B2
• Time in Patent Office: Days
• US Class Current: 349/113
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 2201/123 pixel
• 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

Abstract

It is an object to provide a display having high visibility and a transflective type liquid crystal display device having a reflection electrode having a concavo-convex structure formed without especially increasing the process. During manufacturing a transflective liquid crystal display device, a reflection electrode of a plurality of irregularly arranged island-like patterns and a transparent electrode of a transparent conductive film are layered in forming an electrode having transparent and reflection electrodes thereby having a concavo-convex form to enhance the scattering ability of light and hence the visibility of display. Furthermore, because the plurality of irregularly arranged island-like patterns can be formed simultaneous with an interconnection, a concavo-convex structure can be formed during the manufacturing process without especially increasing the patterning process only for forming a concavo-convex structure. It is accordingly possible to greatly reduce cost and improve productivity.

Claims

1. A liquid crystal display device comprising:

a transparent conductive film formed on an insulating surface; and

an interconnection and a plurality of island-like conductive films that are formed on the transparent conductive film,

wherein the transparent conductive film, the interconnection and the plurality of irregularly arranged island-like patterns are electrically connected.

2. A liquid crystal display device according to claim 1, wherein the plurality of island-like conductive films each have a pattern end having a taper angle of 5-60 degrees.

3. A liquid crystal display device according to claim 1, wherein the plurality of island-like conductive films have an area ratio of 50-90% of an area occupied by the transparent conductive film.

4. A liquid crystal display device according to claim 1, wherein the liquid crystal display device is incorporated into an electronic apparatus selected from the group consisting of a digital still camera, a notebook personal computer, a mobile computer, a portable type image reproducing apparatus having a recording medium, a video camera and a cellular phone.

33. A liquid crystal display device according to claim 1, wherein the transparent conductive film is a pixel electrode.

41. A liquid crystal display device according to claim 1, wherein the plurality of island-like conductive films are irregularly arranged.

5. A liquid crystal display device comprising:

a transparent conductive film formed on an insulating surface; and

an interconnection and a plurality of island-like conductive films that are simultaneously formed on the transparent conductive film,

wherein the transparent conductive film, the interconnection and the plurality of irregularly arranged island-like patterns are electrically connected.

6. A liquid crystal display device according to claim 5, wherein the plurality of island-like conductive films each have a pattern end having a taper angle of 5-60 degrees.

7. A liquid crystal display device according to claim 5, wherein the plurality of island-like conductive films have an area ratio of 50-90% of an area occupied by the transparent conductive film.

8. A liquid crystal display device according to claim 5, wherein the liquid crystal display device is incorporated into an electronic apparatus selected from the group consisting of a digital still camera, a notebook personal computer, a mobile computer, a portable type image reproducing apparatus having a recording medium, a video camera and a cellular phone.

34. A liquid crystal display device according to claim 5, wherein the transparent conductive film is a pixel electrode.

42. A liquid crystal display device according to claim 5, wherein the plurality of island-like conductive films are irregularly arranged.

9. A liquid crystal display device comprising:

a thin-film transistor formed over a substrate;

a transparent conductive film formed over the thin-film transistor through an insulating film; and

an interconnection and a plurality of island-like conductive films that are formed on the transparent conductive film,

wherein the thin-film transistor and the transparent conductive film are electrically connected via the interconnection.

10. A liquid crystal display device according to claim 9, wherein the plurality of island-like conductive films each have a pattern end having a taper angle of 5-60 degrees.

11. A liquid crystal display device according to claim 9, wherein the plurality of island-like conductive films have an area ratio of 50-90% of an area occupied by the transparent conductive film.

12. A liquid crystal display device according to claim 9, wherein the liquid crystal display device is incorporated into an electronic apparatus selected from the group consisting of a digital still camera, a notebook personal computer, a mobile computer, a portable type image reproducing apparatus having a recording medium, a video camera and a cellular phone.

35. A liquid crystal display device according to claim 9, wherein the transparent conductive film is a pixel electrode.

43. A liquid crystal display device according to claim 9, wherein the plurality of-island-like conductive films are irregularly arranged.

13. A liquid crystal display device comprising:

a thin-film transistor formed over a substrate;

a transparent conductive film formed over the thin-film transistor through an insulating film; and

an interconnection and a plurality of island-like conductive films that are simultaneously formed on the transparent conductive film,

wherein the thin-film transistor and the transparent conductive film are electrically connected via the interconnection.

14. A liquid crystal display device according to claim 13, wherein the plurality of island-like conductive films each have a pattern end having a taper angle of 5-60 degrees.

15. A liquid crystal display device according to claim 13, wherein the plurality of island-like conductive films have an area ratio of 50-90% of an area occupied by the transparent conductive film.

16. A liquid crystal display device according to claim 13, wherein the liquid crystal display device is incorporated into an electronic apparatus selected from the group consisting of a digital still camera, a notebook personal computer, a mobile computer, a portable type image reproducing apparatus having a recording medium, a video camera and a cellular phone.

36. A liquid crystal display device according to claim 13, wherein the transparent conductive film is a pixel electrode.

44. A liquid crystal display device according to claim 13, wherein the plurality of island-like conductive films are irregularly arranged.

17. A liquid crystal display device comprising:

a first substrate having a first transparent conductive film, an interconnection and a plurality of island-like conductive films;

a second substrate having a second transparent conductive film; and

a liquid crystal between the first substrate and the second substrate;

wherein the interconnection and the plurality of island-like conductive films are formed on the first transparent conductive film,

wherein the transparent conductive film, the interconnection and the plurality of island-like conductive films are electrically connected,

wherein a film forming surface of the first substrate and a film forming surface of the second substrate are arranged opposite to each other.

18. A liquid crystal display device according to claim 17, wherein the plurality of island-like conductive films each have a pattern end having a taper angle of 5-60 degrees.

19. A liquid crystal display device according to claim 17, wherein the plurality of island-like conductive films have an area ratio of 50-90% of an area occupied by the transparent conductive film.

20. A liquid crystal display device according to claim 17, wherein the liquid crystal display device is incorporated into an electronic apparatus selected from the group consisting of a digital still camera, a notebook personal computer, a mobile computer, a portable type image reproducing apparatus having a recording medium, a video camera and a cellular phone.

37. A liquid crystal display device according to claim 17, wherein the transparent conductive film is a pixel electrode.

45. A liquid crystal display device according to claim 17, wherein the plurality of island-like conductive films are irregularly arranged.

21. A liquid crystal display device comprising:

a first substrate having a first transparent conductive film, an interconnection and a plurality of island-like conductive films;

a second substrate having a second transparent conductive film; and

a liquid crystal between the first substrate and the second substrate;

wherein the interconnection and the plurality of island-like conductive films are simultaneously formed on the first transparent conductive film;

wherein the transparent conductive film, the interconnection and the plurality of island-like conductive films are electrically connected;

wherein a film forming surface of the first substrate and a film forming surface of the second substrate are arranged opposite to each other.

22. A liquid crystal display device according to claim 21, wherein the plurality of island-like conductive films each have a pattern end having a taper angle of 5-60 degrees.

23. A liquid crystal display device according to claim 21, wherein the plurality of island-like conductive films have an area ratio of 50-90% of an area occupied by the transparent conductive film.

24. A liquid crystal display device according to claim 21, wherein the liquid crystal display device is incorporated into an electronic apparatus selected from the group consisting of a digital still camera, a notebook personal computer, a mobile computer, a portable type image reproducing apparatus having a recording medium, a video camera and a cellular phone.

38. A liquid crystal display device according to claim 21, wherein the transparent conductive film is a pixel electrode.

46. A liquid crystal display device according to claim 21, wherein the plurality of island-like conductive films are irregularly arranged.

25. A liquid crystal display device comprising:

a first substrate having a thin-film transistor, a first transparent conductive film, an interconnection and a plurality of island-like conductive films;

a second substrate having a second transparent conductive film; and

a liquid crystal between the first substrate and the second substrate,

wherein the interconnection and the plurality of island-like conductive films are formed on the first transparent conductive film,

wherein the thin-film transistor, the first transparent conductive film and the plurality of island-like conductive films are electrically connected via the interconnection,

wherein a film forming surface of the first substrate and a film forming surface of the second substrate are arranged opposite to each other.

26. A liquid crystal display device according to claim 25, wherein the plurality of island-like conductive films each have a pattern end having a taper angle of 5-60 degrees.

27. A liquid crystal display device according to claim 25, wherein the plurality of island-like conductive films have an area ratio of 50-90% of an area occupied by the transparent conductive film.

28. A liquid crystal display device according to claim 25, wherein the liquid crystal display device is incorporated into an electronic apparatus selected from the group consisting of a digital still camera, a notebook personal computer, a mobile computer, a portable type image reproducing apparatus having a recording medium, a video camera and a cellular phone.

39. A liquid crystal display device according to claim 25, wherein the transparent conductive film is a pixel electrode.

47. A liquid crystal display device according to claim 25, wherein the plurality of island-like conductive films are irregularly arranged.

29. A liquid crystal display device comprising:

a first substrate having a thin-film transistor, a first transparent conductive film, an interconnection and a plurality of island-like conductive films;

a second substrate having a second transparent conductive film; and

a liquid crystal between the first substrate and the second substrate;

wherein the interconnection and the plurality of island-like conductive films are simultaneously formed on the first transparent conductive film,

wherein the thin-film transistor, the first transparent conductive film and the plurality of island-like conductive films are electrically connected via the interconnection,

wherein a film forming surface of the first substrate and a film forming surface of the second substrate are arranged opposite to each other.

30. A liquid crystal display device according to claim 29, wherein the plurality of island-like conductive films each have a pattern end having a taper angle of 5-60 degrees.

31. A liquid crystal display device according to claim 29, wherein the plurality of island-like conductive films have an area ratio of 50-90% of an area occupied by the transparent conductive film.

32. A liquid crystal display device according to claim 29, wherein the liquid crystal display device is incorporated into an electronic apparatus selected from the group consisting of a digital still camera, a notebook personal computer, a mobile computer, a portable type image reproducing apparatus having a recording medium, a video camera and a cellular phone.

40. A liquid crystal display device according to claim 29, wherein the transparent conductive film is a pixel electrode.

48. A liquid crystal display device according to claim 29, wherein the plurality of island-like conductive films are irregularly arranged.