Liquid crystal display device including light shielding film

• US 9,250,490 B2
• Filed: 10/29/2014
• Issued: 02/02/2016
• Est. Priority Date: 08/31/1999
• Status: Expired due to Term

• 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:
  US14/527,020
• Publication Number:
  US 20150049278A1
• Time in Patent Office: 461 Days
• US Class Current: 1/1
• 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 liquid crystal display device comprising:

a first substrate;

a second substrate;

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

a pixel including a light shielding film, a first insulating film over the light shielding film, a semiconductor film containing a source region, a channel forming region, and a drain region over the first insulating film, a gate insulating film over the semiconductor film, a gate electrode over the gate insulating film, a second insulating film over the gate electrode, an electrode over the second insulating film, a signal line over the second insulating film, an organic resin film over the electrode and the signal line, and a pixel electrode over the organic resin film,

wherein a contact hole is provided in the organic resin film,

wherein one of the source region and the drain region includes a first region not overlapping the light shielding film,

wherein the electrode is in contact with at least a portion of the first region,

wherein a width of the channel forming region is smaller than a largest width of the first region,

wherein the signal line is electrically connected to the other of the source region and the drain region,

wherein the electrode and the signal line are electrically connected to the semiconductor film,

wherein the pixel electrode is electrically connected to the electrode through the contact hole,

wherein each of the light shielding film and the gate electrode contains at least one of Al, Ta, Mo, W, and Cr,

wherein each of the signal line and the electrode contains at least one of Al, W, and Ti, and

wherein the light shielding film includes a region overlapped with the channel forming region, a region overlapped with the gate electrode, a region overlapped with the signal line, a region overlapped with the electrode, a region overlapped with the contact hole, and a region overlapped with the pixel electrode.

2. The liquid crystal display device according to claim 1, wherein the light shielding film is a scanning line.

3. The liquid crystal display device according to claim 2, wherein the gate electrode is electrically connected to the scanning line.

4. The liquid crystal display device according to claim 1, wherein the liquid crystal 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.

5. A liquid crystal display device comprising:

a first substrate;

a second substrate;

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

a pixel including a light shielding film, a first insulating film over the light shielding film, a semiconductor film containing a source region, a channel forming region, and a drain region over the first insulating film, a gate insulating film over the semiconductor film, a gate electrode over the gate insulating film, a second insulating film over the gate electrode, an electrode over the second insulating film, a signal line over the second insulating film, an organic resin film over the electrode and the signal line, a conductive film over the organic resin film, a third insulating film over the conductive film, and a pixel electrode over the third insulating film,

wherein a contact hole is provided in the organic resin film,

wherein a capacitor is formed by at least the pixel electrode, the third insulating film, and the conductive film,

wherein one of the source region and the drain region includes a first region not overlapping the light shielding film,

wherein the electrode is in contact with at least a portion of the first region,

wherein a width of the channel forming region is smaller than a largest width of the first region,

wherein the signal line is electrically connected to the other of the source region and the drain region,

wherein the electrode and the signal line are electrically connected to the semiconductor film,

wherein the pixel electrode is electrically connected to the electrode through the contact hole,

wherein each of the light shielding film and the gate electrode contains at least one of Al, Ta, Mo, W, and Cr,

wherein each of the signal line and the electrode contains at least one of Al, W, and Ti, and

wherein the light shielding film includes a region overlapped with the channel forming region, a region overlapped with the gate electrode, a region overlapped with the signal line, a region overlapped with the electrode, a region overlapped with the contact hole, a region overlapped with the conductive film, and a region overlapped with the pixel electrode.

6. The liquid crystal display device according to claim 5, wherein the light shielding film is a scanning line.

7. The liquid crystal display device according to claim 6, wherein the gate electrode is electrically connected to the scanning line.

8. The liquid crystal display device according to claim 5, wherein the conductive film has light blocking characteristics.

9. The liquid crystal display device according to claim 5, wherein the liquid crystal 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.

10. A liquid crystal display device comprising:

a first substrate;

a second substrate;

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

a pixel including a light shielding film, a first insulating film over the light shielding film, a semiconductor film containing a source region, a channel forming region, and a drain region over the first insulating film, a gate insulating film over the semiconductor film, a gate electrode over the gate insulating film, a second insulating film over the gate electrode, an electrode over the second insulating film, a signal line over the second insulating film, an organic resin film over the electrode and the signal line, and a pixel electrode over the organic resin film,

wherein a contact hole is provided in the organic resin film,

wherein one of the source region and the drain region includes a first region not overlapping the light shielding film,

wherein the electrode is in contact with at least a portion of the first region,

wherein a width of the channel forming region is smaller than a largest width of the first region,

wherein the signal line is electrically connected to the other of the source region and the drain region,

wherein the electrode and the signal line are electrically connected to the semiconductor film,

wherein the pixel electrode is electrically connected to the electrode through the contact hole,

wherein each of the light shielding film and the gate electrode contains at least one of Al, Ta, Mo, W, and Cr,

wherein each of the signal line and the electrode contains at least one of Al, W, and Ti,

wherein the light shielding film includes a second region overlapped with the semiconductor film, and

wherein the second region includes a region overlapped with the gate electrode, a region overlapped with the signal line, a region overlapped with the electrode, a region overlapped with the contact hole, and a region overlapped with the pixel electrode.

11. The liquid crystal display device according to claim 10, wherein the light shielding film is a scanning line.

12. The liquid crystal display device according to claim 11, wherein the gate electrode is electrically connected to the scanning line.

13. The liquid crystal display device according to claim 10, wherein the liquid crystal 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. A liquid crystal display device comprising:

a first substrate;

a second substrate;

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

a pixel including a light shielding film, a first insulating film over the light shielding film, a semiconductor film containing a source region, a channel forming region, and a drain region over the first insulating film, a gate insulating film over the semiconductor film, a gate electrode over the gate insulating film, a second insulating film over the gate electrode, an electrode over the second insulating film, a signal line over the second insulating film, an organic resin film over the electrode and the signal line, a conductive film over the organic resin film, a third insulating film over the conductive film, and a pixel electrode over the third insulating film,

wherein a contact hole is provided in the organic resin film,

wherein a capacitor is formed by at least the pixel electrode, the third insulating film, and the conductive film,

wherein one of the source region and the drain region includes a first region not overlapping the light shielding film,

wherein the electrode is in contact with at least a portion of the first region,

wherein a width of the channel forming region is smaller than a largest width of the first region,

wherein the signal line is electrically connected to the other of the source region and the drain region,

wherein the electrode and the signal line are electrically connected to the semiconductor film,

wherein the pixel electrode is electrically connected to the electrode through the contact hole,

wherein each of the light shielding film and the gate electrode contains at least one of Al, Ta, Mo, W, and Cr,

wherein each of the signal line and the electrode contains at least one of Al, W, and Ti,

wherein the light shielding film includes a second region overlapped with the semiconductor film, and

wherein the second region includes a region overlapped with the gate electrode, a region overlapped with the signal line, a region overlapped with the electrode, a region overlapped with the contact hole, a region overlapped with the conductive film, and a region overlapped with the pixel electrode.

15. The liquid crystal display device according to claim 14, wherein the light shielding film is a scanning line.

16. The liquid crystal display device according to claim 15, wherein the gate electrode is electrically connected to the scanning line.

17. The liquid crystal display device according to claim 14, wherein the conductive film has light blocking characteristics.

18. The liquid crystal display device according to claim 14, wherein the liquid crystal 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.