Display device including a transparent electrode pattern covering and extending along gate & source lines

• US 6,421,101 B1
• Filed: 04/07/2000
• Issued: 07/16/2002
• 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): Sikes, William L.
• Assistant Examiner(s): Chowdhury, Tarifur R.
• Application Number:
  US09/546,636
• Time in Patent Office: 830 Days
• Field of Search: 349/39, 349/111, 349/43, 349/138, 349/42, 349/38, 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. A semiconductor device comprising:

at least one thin film transistor formed over a substrate, said thin film transistor having an active layer comprising at least channel, source, and drain regions;

source and gate lines intersecting each other and connected to said thin film transistor, said source line overlapping with a contact portion in said source region of said thin film transistor; and

an electrode pattern covering and extending along said source and gate lines, said electrode pattern comprises a transparent material; and

a pixel electrode formed over said electrode pattern and connected to said drain region of said thin film transistor, ends of said pixel electrode overlapping said source and gate lines with the electrode pattern interposed therebetween.

2. A device according to claim 1, wherein said electrode pattern comprises ITO.

3. A device according to claim 1, wherein a material of said electrode pattern is the same as that of the pixel electrode.

4. A device according to claim 1, wherein an auxiliary capacitor is formed between said electrode pattern and said pixel electrode.

5. A device according to claim 1, wherein said pixel electrode comprises a transparent material.

6. A device according to claim 1, wherein said thin film transistor comprises at least two channel regions.

7. A semiconductor display device comprising:

at least one thin film transistor formed over a substrate, said thin film transistor having an active layer comprising al least channel, source, and drain regions;

source and gate lines intersecting each other and connected to said thin film transistor;

an electrode pattern covering and extending along said source and gate lines, said electrode pattern comprises a transparent material; and

a pixel electrode connected to said drain region of said thin film transistor, ends of said pixel electrode overlapping said source and gate lines with the electrode pattern interposed therebetween,

wherein a contact portion in said source region does not overlap with said pixel electrode.

8. A device according to claim 7, wherein said electrode pattern comprises ITO.

9. A device according to claim 7, wherein a material of said electrode pattern is the same as that of the pixel electrode.

10. A device according to claim 7, wherein an auxiliary capacitor is formed between said electrode pattern and said pixel electrode.

11. A device according to claim 7, wherein said pixel electrode comprises a transparent material.

12. A device according to claim 7, wherein said thin film transistor comprises at least two channel regions.

13. A semiconductor display device comprising:

at least one thin film transistor formed over a substrate, said thin film transistor having an active layer comprising at least channel, source, and drain regions;

source and gate lines intersecting each other and connected to said thin film transistor;

an electrode pattern covering and extending along said source and gate lines, said electrode pattern comprises a transparent material; and

a pixel electrode directly connected with said drain region, ends of said pixel electrode overlapping said source and gate lines with the electrode pattern interposed therebetween,

wherein said electrode pattern covers an intersection of the source and gate lines.

14. A device according to claim 13, wherein said electrode pattern comprises ITO.

15. A device according to claim 13, wherein a material of said electrode pattern is the same as that of the pixel electrode.

16. A device according to claim 13, wherein an auxiliary capacitor is formed between said electrode pattern and said pixel electrode.

17. A device according to claim 13, wherein said pixel electrode comprises a transparent material.

18. A device according to claim 13, wherein said thin film transistor comprises at least two channel regions.

19. An active matrix type display device, comprising:

at least one thin film transistor formed over a substrate;

source and gate lines intersecting each other and connected to said thin film transistor;

an electrode pattern covering and extending along said source and gate lines, said electrode pattern comprises a transparent material; and

a pixel electrode formed over said electrode pattern, ends of said pixel electrode overlapping said source and gate lines with said electrode pattern interposed therebetween,

wherein said electrode pattern functions as a shield film for electrically shielding said source and gate lines from said pixel electrode.

20. A device according to claim 19, wherein said electrode pattern comprises ITO.

21. A device according to claim 19, wherein a material of said electrode pattern is the same as that of the pixel electrode.

22. A device according to claim 19, wherein an auxiliary capacitor is formed between said electrode pattern and said pixel electrode.

23. A device according to claim 19, wherein said pixel electrode comprises a transparent material.

24. A device according to claim 19, wherein said thin film transistor comprises at least two channel regions.

25. A semiconductor device comprising:

at least one thin film transistor formed over a substrate, said thin film transistor having an active layer comprising at least channel, source, and drain regions;

source and gate lines intersecting each other and connected to said thin film transistor, said source line overlapping with a contact portion in said source region of said

thin film transistor; and

an electrode pattern extending along said source and gate lines, said electrode pattern comprising a first layer and a second layer; and

a pixel electrode formed over said electrodes and connected to said drain region of said thin film transistor, ends of said pixel electrode overlapping with said source and gate lines,

wherein said first layer comprises metal and said second layer comprises a transparent material.

26. A device according to claim 25, wherein said first layer comprises Ti or Cr.

27. A device according to claim 25, wherein said second layer comprises ITO.

28. A device according to claim 25, wherein a material of said electrode pattern is the same as that of the pixel electrode.

29. A device according to claim 25, wherein an auxiliary capacitor formed between said electrode pattern and said pixel electrode.

30. A device according to claim 25, wherein said pixel electrode comprises a transparent material.

31. A device according to claim 25, wherein said thin film transistor comprises at least two channel regions.