Display device

• US 6,115,088 A
• Filed: 09/03/1997
• Issued: 09/05/2000
• Est. Priority Date: 09/04/1996
• Status: Expired due to Term

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Teramoto, Satoshi, Zhang, Hongyong
• Primary Examiner(s): MALINOWSKI, WALTER J
• Application Number:
  US08/922,951
• Time in Patent Office: 1,098 Days
• Field of Search: 349/38, 349/39, 349/111, 349/138, 349/42, 349/43, 257/59, 257/72
• US Class Current: 349/39
• CPC Class Codes: G02F 1/136209 Light shielding layers, e.g. black matrix, incorporated in the active matrix substrate, e.g. structurally associated with the switching element
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer

Abstract

The present invention provides an active matrix type display device having a high aperture ratio and a required auxiliary capacitor. A source line and a gate line are overlapped with part of a pixel electrode. This overlapped region functions to be a black matrix. Further, an electrode pattern made of the same material as the pixel electrode is disposed to form the auxiliary capacitor by utilizing the pixel electrode. It allows a required value of auxiliary capacitor to be obtained without dropping the aperture ratio. Also, it allows the electrode pattern to function as a electrically shielding film for suppressing the cross-talk between the source and gate lines and the pixel electrode.

Claims

1. An active matrix type display device, comprising:

a pixel electrode;

at least one switching element connected to said pixel electrode;

an electrode pattern made of a transparent conductive film disposed between source and gate lines and said pixel electrode; and

an auxiliary capacitor formed between said electrode pattern and said pixel electrode,

wherein said electrode pattern extends over at least a portion of said source line.

2. A device according to claim 1, wherein said electrode pattern made of the transparent conductive film functions as a shield film for electrically shielding said source and gate lines from said pixel electrode.

3. A device according to claim 1, wherein said switching element is a thin film transistor.

4. A device according to claim 1, wherein a material of said electrode pattern is ITO.

5. An active matrix type display device, comprising:

a pixel electrode;

at least one switching element connected to said pixel electrode;

an electrode pattern made of a transparent conductive film disposed between source and gate lines and said pixel electrode;

an edge of said pixel electrode being disposed so as to overlap with said source and gate lines;

an auxiliary capacitor formed between said electrode pattern made of said transparent conductive film and said pixel electrode.

6. A device according to claim 5, wherein said electrode pattern made of the transparent conductive film functions as a shield film for electrically shielding said source and gate lines from said pixel electrode.

7. A device according to claim 5, wherein said switching element is a thin film transistor.

8. A device according to claim 5, wherein a material of said electrode pattern is ITO.

9. An active matrix type display device comprising:

a transparent pixel electrode;

at least one switching element connected to said transparent pixel electrode; and

an electrode pattern made of a transparent conductive film disposed between said switching element so as to cover source and gate lines.

10. A device according to claim 9, wherein said electrode pattern made of said transparent conductive film overlaps partially with said pixel electrode to form an auxiliary capacitor.

11. A device according to claim 9, wherein said electrode pattern made of the transparent conductive film functions as a shield film for electrically shielding said source and gate lines from said pixel electrode.

12. A device according to claim 9, wherein said switching element is a thin film transistor.

13. A device according to claim 9, wherein a material of said electrode pattern is ITO.

14. An active matrix type display device comprising:

a semiconductor film over a substrate having an insulating surface thereon;

a gate insulating film over said semiconductor film;

a first interlayer insulating film over said gate insulating film;

a wiring formed on said first interlayer film and connected to said semiconductor layer via a contact;

a second interlayer insulating film over said wiring and first interlayer;

an electrode pattern on said second interlayer insulating film so as to cover said wiring;

a third interlayer insulating film over said electrode pattern and said second interlayer insulating film; and

a pixel electrode on said third interlayer insulating film so as to overlap with said electrode pattern,

wherein a material of said electrode pattern is the same as that of the pixel electrode.

15. A device according to claim 14, wherein said material of said electrode pattern is transparent.

16. A device according to claim 14, wherein said first interlayer insulating film is laminate film comprising a silicon nitride film and a polyimide film.

17. A device according to claim 14, wherein said second and third interlayer insulating films comprise polyimide.

18. An active matrix type display device comprising:

a semiconductor film over a substrate having an insulating surface thereon;

a gate insulating film over said semiconductor film;

a first interlayer insulating film over said gate insulating film;

a wiring formed on said first interlayer film and connected to said semiconductor layer via a contact;

a second interlayer insulating film over said wiring and first interlayer;

a black matrix on said second interlayer insulating film so as to cover said wiring;

an electrode pattern on said black matrix and said second interlayer insulating film so as to cover said wiring and said black matrix;

a third interlayer insulating film over said electrode pattern and said second interlayer insulating film; and

a pixel electrode on said third interlayer insulating film so as to overlap with said electrode pattern,

wherein a material of said electrode pattern is the same as that of the pixel electrode.

19. A device according to claim 18, wherein said black matrix comprising a metal selected from titanium and chromium.

20. A device according to claim 18, wherein said material of said electrode pattern and said pixel electrode is transparent.

21. A device according to claim 18, wherein said first interlayer insulating film is laminate film comprising a silicon nitride film and a polyimide film.

22. A device according to claim 18, wherein said second and third interlayer insulating films comprise polyimide.

23. An active matrix type display device comprising:

a semiconductor film over a substrate having an insulating surface;

a gate electrode adjacent to said semiconductor film with a gate insulating film interposed therebetween;

source and drain wirings connected to said semiconductor layer, respectively;

an transparent electrode pattern so as to cover at least a portion of said source wiring;

an insulating film over said transparent electrode pattern; and

a pixel electrode on said interlayer insulating film.

24. A device according to claim 23, wherein said electrode pattern comprises ITO.

25. A device according to claim 23, wherein said source and drain wirings are connected to said semiconductor layer through an insulating film comprising at least silicon and nitrogen.

26. A device according to claim 23, wherein said interlayer insulating film comprises polyimide.

27. An active matrix type display device comprising:

a semiconductor film over a substrate having an insulating surface;

a gate electrode adjacent to said semiconductor film with a gate insulating film interposed therebetween;

an insulating film over said semiconductor film and said gate electrode;

source and drain wirings connected to said semiconductor layer via contact holes in said insulating film;

a black matrix adjacent to at least said source wiring;

an transparent electrode pattern over at least said source wiring;

an interlayer insulating film over said electrode pattern; and

a pixel electrode over said transparent electrode pattern.

28. A device according to claim 27, wherein said black matrix comprises a metal selected from titanium and chromium.

29. A device according to claim 27, wherein said electrode pattern and said pixel electrode comprise ITO.

30. A device according to claim 27, wherein said insulating film comprises at least silicon and nitrogen.

31. A device according to claim 27, wherein said interlayer insulating film comprises polyamide.

32. An active matrix type display device, comprising:

at least one thin film transistor having a U-shaped active layer;

an electrode pattern made of a conductive film disposed between source and gate lines and a pixel electrode; and

an auxiliary capacitor formed between said electrode pattern and said pixel electrode.

33. A device according to claim 32, wherein said electrode pattern made of the conductive film functions as a shield film for electrically shielding said source and gate lines from said pixel electrode.

34. A device according to claim 32, wherein a material of said electrode pattern is the same as that of the pixel electrode.

35. A device according to claim 32, wherein a material of said electrode pattern is transparent.

36. An active matrix type display device, comprising:

at least one thin film transistor having a semiconductor active layer having a plurality of channel regions therein, said thin film transistor connected to a pixel electrode;

source and gate lines connected to said thin film transistor;

an electrode pattern made of a conductive film disposed over at least said source lines;

an auxiliary capacitor formed between said electrode pattern made of said conductive film and said pixel electrode.

37. A device according to claim 36, wherein said electrode pattern made of the conductive film functions as a shield film for electrically shielding said source and gate lines from said pixel electrode.

38. A device according to claim 36, wherein a material of said electrode pattern is the same as that of the pixel electrode.

39. A device according to claim 36, wherein a material of said electrode pattern is transparent.

40. An active matrix type display device comprising:

at least one semiconductor island over a substrate having an insulating surface, said semiconductor island having at least one curved portion;

a gate electrode adjacent to said semiconductor island;

a wiring connected to said semiconductor island;

an insulating film over said wiring;

an electrode pattern covering at least a portion of said wiring;

an interlayer insulating film over said electrode pattern; and

a pixel electrode on said interlayer insulating film so as to overlap with at least a portion of said electrode pattern,

wherein said semiconductor island has a plurality of channel regions.

41. A device according to claim 40, wherein said electrode pattern and said pixel electrode are transparent.

42. A device according to claim 40, wherein said electrode pattern and said pixel electrode comprise ITO.

43. A device according to claim 40, wherein said interlayer insulating film comprises polyamide.