Substrate for electro-optical apparatus, electro-optical apparatus, method for driving electro-optical apparatus, electronic device and projection display device

• US 6,066,860 A
• Filed: 12/23/1998
• Issued: 05/23/2000
• Est. Priority Date: 12/25/1997
• Status: Expired due to Term

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Yasukawa, Masahiro, Katayama, Shigenori
• Primary Examiner(s): Ngo , Ngan V.
• Application Number:
  US09/219,708
• Time in Patent Office: 517 Days
• Field of Search: 257/71, 257/296, 257/350, 257/59, 257/72
• US Class Current: 257/71
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G09G 3/3659 the addressing of the pixel involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependant on signal of two data electrodes
• CPC Class Codes: H01L 27/12 the substrate being other than a semiconductor body, e.g. an insulating body
• CPC Class Codes: H01L 27/1203 the substrate comprising an insulating body on a semiconductor body, e.g. SOI three-dimensional layout H01L27/0688
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/78609 for preventing leakage current H01L29/78618 takes precedence
• 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 29/78633 with a light shield

Abstract

In a conventional MOS semiconductor device of a thin film SOI structure, excessive carriers accumulated in the channel region cause some problems, such as a decreased drain breakdown voltage and formation of kink in the current-voltage relationship, resulting in malfunction. Accordingly, drainage of the excessive carriers accumulated in the semiconductor layer functioning as a channel region of the thin film transistor on a substrate for electro-optical apparatuses is achieved.

Claims

1. An electro-optical apparatus comprising;

a substrate;

a matrix of pixel regions formed on the substrate;

a transistor having a gate electrode and a channel region provided to each of the matrix of pixel regions;

a first scanning signal line electrically connected to the sate electrode of said transistor; and

a semiconductor layer constituting the channel region of the transistor formed on the substrate, the semiconductor layer being electrically connected to a second scanning signal line.

2. The electro-optical apparatus according to claim 1, said second scanning signal line being positioned at a preceding side of the first scanning signal line.

3. The electro-optical apparatus according to claim 2, the transistor being an N-channel type transistor and a potential which is equal to or lower than that of an image signal supplied to the transistor being applied to the preceding side of the first scanning signal line.

4. The electro-optical apparatus according to claim 2, the transistor being a P-channel type transistor and a potential which is equal to or higher than that of an image signal supplied to the transistor being applied to the preceding side of the first scanning signal line.

5. The electro-optical apparatus according to claim 1, the transistor further having a source/drain region, and the semiconductor layer constituting the channel region of the transistor being a conductive type different from a conductive type of a semiconductor layer constituting the source/drain region.

6. The electro-optical apparatus according to claim 5, the semiconductor layer constituting the channel region of the transistor being doped with an impurity having a lower concentration than a concentration in the semiconductor layer constituting the source/drain region of the transistor.

7. The electro-optical apparatus according to claim 1, the semiconductor layer constituting the channel region having an extended section and the extended section being electrically connected to the second scanning signal line.

8. The electro-optical apparatus according to claim 7, the transistor further having a source/drain region, and the semiconductor layer constituting the channel region and the semiconductor layer constituting the extended section being a conductive type different from a conductive type of the semiconductor layer constituting the source/drain region.

9. The electro-optical apparatus according to claim 8, the semiconductor layer constituting the extended section being doped with an impurity having a higher concentration than a concentration of the semiconductor layer constituting the channel region.

10. The electro-optical apparatus according to claim 1, the transistor being an N-channel type transistor and a non-selection potential equal to or lower than that of the image signal supplied to the transistor being applied to said second scanning signal line.

11. The electro-optical apparatus according to claim 1, the transistor being a P-channel type transistor and a non-selection potential equal to or higher than that of the image signal supplied to the transistor being applied to said second scanning signal line.

12. The electro-optical apparatus according to claim 1, the channel region of the transistor comprising a single-crystal silicon layer.

13. The electro-optical apparatus according to claim 12, charges accumulated in the channel region of the transistor being drained through said second scanning signal line.

32. The electro-optical apparatus according to claim 1, the channel region being electrically connected to a wiring branched from said second scanning signal line or a wiring connected to said second scanning signal line.

33. The electro-optical apparatus according to claim 32, the wiring branched from said second scanning signal line or the wiring connected to the second scanning signal line being arranged along a periphery of a pixel region.

34. The electro-optical apparatus according to claim 33, the wiring branched from said second scanning signal line or the wiring connected to said second scanning signal line being arranged along an image signal line crossing the first scanning signal line and along a scanning signal line provided in a vicinity of the channel region of the transistor.

35. The electro-optical apparatus according to claim 34, the wiring branched from said second scanning signal line or the wiring connected to said second scanning line being arranged so as to overlap in a planar manner with a light shielding layer formed on the substrate below the semiconductor layer.

36. The electro-optical apparatus according to claim 8, the semiconductor layer constituting the channel region and the semiconductor layer constituting the extended section being arranged so as to overlap in a planar manner with a light shielding layer formed on the substrate below the semiconductor layer constituting the channel region.

37. The electro-optical apparatus according to claim 1, the substrate comprising a transparent substrate.

38. The electro-optical apparatus according to claim 37, the transparent substrate comprising glass.

39. The electro-optical apparatus according to claim 37, further comprising a pixel electrode connected to the transistor, the pixel electrode being a transparent electrode.

40. The electro-optical apparatus according to claim 37, further comprising a pixel electrode connected to the transistor, the pixel electrode being a reflective electrode.

41. The electro-optical apparatus according to claim 1, the substrate being a semiconductor substrate.

42. The electro-optical apparatus according to claim 41, the semiconductor substrate comprising single-crystal silicon.

43. The electro-optical apparatus according to claim 42, further comprising a pixel electrode connected to the transistor, the pixel electrode being a reflective electrode.

44. The electro-optical apparatus according to claim 1, further comprising:

a planarized insulating film formed above the transistors, and

a pixel electrode formed on the planarized insulating film.

45. The electro-optical apparatus according to claim 1, further comprising:

an insulating film having a plurality of insulating layers formed above the transistor, an upper layer among the insulating layers being planarized, and

a pixel electrode formed on the planarized upper insulating layer.

46. The electro-optical apparatus according to claim 1, said substrate being a first substrate, the electro-optical apparatus further comprising:

a second substrate provided opposing the first substrate with a gap therebetween, and

an electro-optical material disposed in the gap.

47. An electronic apparatus comprising the electro-optical apparatus according to claim 46 as a display.

48. A projection display apparatus comprising:

a light source,

the electro-optical apparatus according to claim 46 that modulates light from the light source, and

a projection optical device that projects the light modulated by the electro-optical apparatus.

14. An electro-optical apparatus comprising:

a substrate;

a matrix of pixel regions formed on the substrate;

an N-channel type transistor having a channel region provided to each of the matrix of pixel regions; and

a semiconductor layer constituting the channel region of the N-channel type transistor formed on the substrate, the semiconductor layer being electrically connected to a conductive layer and a potential equal to or lower than that of an image signal supplied to the transistor being applied to the semiconductor layer.

15. The electro-optical apparatus according to claim 14, the transistor further having a gate electrode, and the conductive layer being positioned at a preceding side of a scanning signal line electrically connected to the gate electrode.

16. The electro-optical apparatus according to claim 14, further comprising a capacitor having a first electrode and a second electrode, the conductive layer being the first electrode, and the second electrode being electrically connected to the transistor.

17. The electro-optical apparatus according to claim 14, further comprising a semiconductor layer constituting an extended section electrically connected to the semiconductor layer constituting the channel region, the semiconductor layer constituting the channel region and the semiconductor layer constituting the extended section being doped with a p-type impurity.

50. The electro-optical apparatus according to claim 14, the substrate comprising a transparent substrate.

51. The electro-optical apparatus according to claim 14, the substrate being a semiconductor substrate.

52. The electro-optical apparatus according to claim 14, further comprising:

a planarized insulating film formed above the transistor, and

a pixel electrode formed on the planarized insulating film.

53. The electro-optical apparatus according to claim 14, further comprising:

an insulating film having a plurality of insulating layers formed above the transistor, an upper layer among the insulating layers being planarized, and

a pixel electrode formed on the planarized upper insulating layer.

54. The electro-optical apparatus according to claim 14, said substrate being a first substrate, the electro-optical apparatus further comprising:

a second substrate provided opposing the first substrate with a gap therebetween, and

an electro-optical material disposed in the gap.

18. An electro-optical apparatus comprising:

a substrate;

a matrix of pixel regions formed on the substrate;

a P-channel type transistor having a channel region provided to each of the matrix of pixel regions; and

a semiconductor layer constituting the channel region of the P-channel type transistor formed on the substrate, the semiconductor layer being electrically connected to a conductive layer and a potential equal to or higher than that of an image signal supplied to said transistor being applied to the semiconductor layer.

19. The electro-optical apparatus according to claim 18, the transistor further having a gate electrode, and the conductive layer being positioned at a preceding side of a scanning signal line electrically connected to the gate electrode of the transistor.

20. A substrate for electro-optical apparatus according to claim 18, further comprising a capacitor having a first electrode and a second electrode, the conductive layer being the first electrode and the second electrode being electrically connected to the transistor.

21. The electro-optical apparatus according to claim 18, further comprising a semiconductor layer constituting an extended section electrically connected to the semiconductor layer constituting the channel region, the semiconductor layer constituting the channel region and the semiconductor layer constituting the extended section being doped with an n-type impurity.

55. The electro-optical apparatus according to claim 18, the substrate comprising a transparent substrate.

56. The electro-optical apparatus according to claim 18, the substrate being a semiconductor substrate.

57. The electro-optical apparatus according to claim 18, further comprising:

a planarized insulating film formed above the transistor, and

a pixel electrode formed on the planarized insulating film.

58. The electro-optical apparatus according to claim 18, further comprising:

an insulating film having a plurality of insulating layer formed above the transistor, an upper layer among the insulating layers being planarized, and

a pixel electrode formed on the planarized upper insulating layer.

59. The electro-optical apparatus according to claim 18, said substrate being a first substrate, the electro-optical apparatus further comprising:

a second substrate provided opposing the first substrate with a gap therebetween, and

an electro-optical material disposed in the gap.

22. An electro-optical apparatus comprising:

a substrate;

a matrix of pixel regions formed on the substrate;

a transistor having a source and drain and a channel region, and a capacitor having a first electrode and a second electrode provided to each of the matrix of pixel regions, one of the source and drain of the transistor being electrically connected to the first electrode of the capacitor; and

a semiconductor layer constituting the channel region of the transistor formed on the substrate, the semiconductor layer constituting the channel region being electrically connected to the second electrode of the capacitor.

23. The electro-optical apparatus according to claim 22, the transistor being an N-channel type transistor and a potential equal to or lower than that of the image signal supplied to the transistor being applied to the second electrode of the capacitor.

24. The electro-optical apparatus according to claim 22, the transistor being a P-channel type transistor and a potential equal to or higher than that of the image signal supplied to the transistor being applied to the second electrode of the capacitor.

25. The electro-optical apparatus according to claim 22, the transistor further having a source/drain region, and the semiconductor layer constituting the channel region of the transistor being a conductive type different from of a conductive type a semiconductor layer constituting the source/drain region.

26. The electro-optical apparatus according to claim 25, the semiconductor layer constituting the channel region of the transistor being doped with an impurity having a lower concentration than a concentration in the semiconductor layer constituting the source/drain region.

27. The electro-optical apparatus according to claim 22, the semiconductor layer constituting the channel region having an extended section and the extended section being electrically connected to the second electrode of the capacitor.

28. The electro-optical apparatus according to claim 27, the transistor further having a source/drain region, and the semiconductor layer constituting the channel region and a semiconductor layer constituting the extended section being a different conductive type from a conductive type of a semiconductor layer constituting the source/drain region.

29. The electro-optical apparatus according to claim 28, the semiconductor layer constituting the extended section being doped with an impurity having a higher concentration than a concentration of the semiconductor layer constituting in the channel region.

30. The electro-optical apparatus according to claim 22, the channel region of the transistor comprising a single-crystal silicon layer.

31. The electro-optical apparatus according to claim 30, charges accumulated in the channel region of the transistor being drained through the second electrode of the capacitor.

49. The electro-optical apparatus according to claim 28, the semiconductor layer constituting the channel region and the semiconductor layer constituting the extended section being arranged so as to overlap in a planar manner with a light shielding layer formed on the substrate below the semiconductor layer constituting the channel region.

60. The electro-optical apparatus according to claim 22, the substrate comprising a transparent substrate.

61. The electro-optical apparatus according to claim 22, the substrate being a semiconductor substrate.

62. The electro-optical apparatus according to claim 22, further comprising:

a planarized insulating film formed above the transistor, and

a pixel electrode formed on the planarized insulating film.

63. The electro-optical apparatus according to claim 22, further comprising:

an insulating film having a plurality of insulating layers formed above the transistor, an upper layer among the insulating layer being planarized, and

a pixel electrode formed on the planarized upper insulating layer.

64. The electro-optical apparatus according to claim 22, said substrate being a first substrate, the electro-optical apparatus further comprising:

a second substrate provided opposite from the first substrate with a gap therebetween, and

an electro-optical material disposed in the gap.