Display device having capacitor wiring

• US 8,253,140 B2
• Filed: 01/24/2011
• Issued: 08/28/2012
• Est. Priority Date: 08/31/1999
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Shibata, Hiroshi, Isobe, Atsuo
• Primary Examiner(s): NGO, NGAN V
• Application Number:
  US13/012,448
• Publication Number:
  US 20110114964A1
• Time in Patent Office: 582 Days
• Field of Search: 257/59, 257/72, 257/350, 257/E29.151
• US Class Current: 257/59
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/13454 Drivers integrated on the active matrix substrate G02F1/136277 takes precedence
• 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
• CPC Class Codes: G02F 1/136277 formed on a semiconductor substrate, e.g. of silicon
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: H01L 27/12 the substrate being other than a semiconductor body, e.g. an insulating body
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/786 Thin film transistors, i.e. transistors with a channel being at least partly a thin film transistors having only the source or the drain region on an insulator layer H01L29/0653; thin film FinFETs H01L29/785
• CPC Class Codes: H01L 29/78633 with a light shield
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/1213 the pixel elements being TFTs
• CPC Class Codes: H10K 59/1216 the pixel elements being capacitors
• CPC Class Codes: H10K 59/123 Connection of the pixel electrodes to the thin film transistors [TFT]
• CPC Class Codes: H10K 59/131 Interconnections, e.g. wiring lines or terminals

Abstract

To provide a liquid crystal display device having high quality display by obtaining a high aperture ratio while securing a sufficient storage capacitor (Cs), and at the same time, by dispersing a load (a pixel writing-in electric current) of a capacitor wiring in a timely manner to effectively reduce the load. A scanning line is formed on a different layer from a gate electrode and the capacitor wiring is arranged so as to be parallel with a signal line. Each pixel is connected to the individually independent capacitor wiring via a dielectric. Therefore, variations in the electric potential of the capacitor wiring caused by a writing-in electric current of a neighboring pixel can be avoided, whereby obtaining satisfactory display images.

Claims

1. A display device comprising:

a scanning line over a substrate;

a first insulating film over the scanning line;

a semiconductor layer over the first insulating film;

a second insulating film over the semiconductor layer;

a gate electrode over the second insulating film, wherein the gate electrode is electrically connected to the scanning line;

a third insulating film over the gate electrode;

a source wiring over the third insulating film, wherein the source wiring is electrically connected to the semiconductor layer; and

a capacitor wiring including a portion extending in parallel with the source wiring.

2. The display device according to claim 1, further comprising a scanning line driver circuit and a signal line driver circuit over the substrate.

3. The display device according to claim 1, wherein the semiconductor layer contains crystalline silicon.

4. The display device according to claim 1, wherein the capacitor wiring contains at least one of poly-silicon and tungsten silicide as an upper electrode, and the semiconductor layer as a lower electrode.

5. The display device according to claim 1, wherein the source wiring contains at least one of aluminum and titanium.

6. The display device according to claim 1, wherein the display device is incorporated in one selected from the group consisting of a personal computer, a video camera, a mobile computer, a goggle type display, a player using a recording medium and a digital camera.

7. The display device according to claim 1, wherein the display device is incorporated in one of a front type projector and a rear type projector.

29. The display device according to claim 1, wherein the second insulating film is a gate insulating film.

8. A display device comprising:

a scanning line over a substrate;

a first insulating film over the scanning line;

a semiconductor layer over the first insulating film;

a second insulating film over the semiconductor layer;

a gate electrode over the second insulating film, wherein the gate electrode is electrically connected to the scanning line;

a third insulating film over the gate electrode;

a source wiring over the third insulating film, wherein the source wiring is electrically connected to the semiconductor layer; and

a capacitor wiring including a first portion extending in parallel with the source wiring and a second portion extending in parallel with the scanning line.

9. The display device according to claim 8, further comprising a scanning line driver circuit and a signal line driver circuit over the substrate.

10. The display device according to claim 8, wherein the semiconductor layer contains crystalline silicon.

11. The display device according to claim 8, wherein the capacitor wiring contains at least one of poly-silicon and tungsten silicide as an upper electrode, and the semiconductor layer as a lower electrode.

12. The display device according to claim 8, wherein the source wiring contains at least one of aluminum and titanium.

13. The display device according to claim 8, wherein the display device is incorporated in one selected from the group consisting of a personal computer, a video camera, a mobile computer, a goggle type display, a player using a recording medium and a digital camera.

14. The display device according to claim 8, wherein the display device is incorporated in one of a front type projector and a rear type projector.

30. The display device according to claim 8, wherein the second insulating film is a gate insulating film.

15. A display device comprising:

a scanning line over a substrate;

a first insulating film over the scanning line;

a semiconductor layer over the first insulating film;

a second insulating film over the semiconductor layer;

a gate electrode over the second insulating film, wherein the gate electrode is electrically connected to the scanning line;

a third insulating film over the gate electrode;

a source wiring over the third insulating film, wherein the source wiring is electrically connected to the semiconductor layer; and

a capacitor wiring including a portion extending in parallel with the source wiring, wherein the portion is overlapped with the source wiring.

16. The display device according to claim 15, further comprising a scanning line driver circuit and a signal line driver circuit over the substrate.

17. The display device according to claim 15, wherein the semiconductor layer contains crystalline silicon.

18. The display device according to claim 15, wherein the capacitor wiring contains at least one of poly-silicon and tungsten silicide as an upper electrode, and the semiconductor layer as a lower electrode.

19. The display device according to claim 15, wherein the source wiring contains at least one of aluminum and titanium.

20. The display device according to claim 15, wherein the display device is incorporated in one selected from the group consisting of a personal computer, a video camera, a mobile computer, a goggle type display, a player using a recording medium and a digital camera.

21. The display device according to claim 15, wherein the display device is incorporated in one of a front type projector and a rear type projector.

31. The display device according to claim 15, wherein the second insulating film is a gate insulating film.

22. A display device comprising:

a scanning line over a substrate;

a first insulating film over the scanning line;

a semiconductor layer over the first insulating film;

a second insulating film over the semiconductor layer;

a gate electrode over the second insulating film, wherein the gate electrode is electrically connected to the scanning line;

a third insulating film over the gate electrode;

a source wiring over the third insulating film, wherein the source wiring is electrically connected to the semiconductor layer; and

a capacitor wiring including a first portion extending in parallel with the source wiring and a second portion extending in parallel with the scanning line, wherein the first portion is overlapped with the source wiring and the second portion is overlapped with the scanning line.

23. The display device according to claim 22, further comprising a scanning line driver circuit and a signal line driver circuit over the substrate.

24. The display device according to claim 22, wherein the semiconductor layer contains crystalline silicon.

25. The display device according to claim 22, wherein the capacitor wiring contains at least one of poly-silicon and tungsten silicide as an upper electrode, and the semiconductor layer as a lower electrode.

26. The display device according to claim 22, wherein the source wiring contains at least one of aluminum and titanium.

27. The display device according to claim 22, wherein the display device is incorporated in one selected from the group consisting of a personal computer, a video camera, a mobile computer, a goggle type display, a player using a recording medium and a digital camera.

28. The display device according to claim 22, wherein the display device is incorporated in one of a front type projector and a rear type projector.

32. The display device according to claim 22, wherein the second insulating film is a gate insulating film.