Electro-optical device

• US 6,246,453 B1
• Filed: 07/22/1999
• Issued: 06/12/2001
• Est. Priority Date: 06/25/1996
• Status: Expired due to Term

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Takemura, Yasuhiko, Zhang, Hongyong, Yamaguchi, Naoaki
• Primary Examiner(s): Dudek, James A.
• Application Number:
  US09/360,841
• Time in Patent Office: 691 Days
• Field of Search: 349/138, 349/122, 349/43, 349/39, 349/38
• 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
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 2201/121 common or background
• CPC Class Codes: G02F 2201/40 Arrangements for improving the aperture ratio

Abstract

An auxiliary capacitor for a pixel of an active matrix type liquid crystal display is provided without decreasing the aperture ratio. A transparent conductive film for a common electrode is formed under a pixel electrode constituted by a transparent conductive film with an insulation film provided therebetween. Further, the transparent conductive film for the common electrode is maintained at fixed potential, formed so as to cover a gate bus line and a source bus line, and configured such that signals on each bus line are not applied to the pixel electrode. The pixel electrode is disposed so that all edges thereof overlap the gate bus line and source bus line. As a result, each of the bus lines serves as a black matrix. Further, the pixel electrode overlaps the transparent conductive film for the common electrode to form a storage capacitor.

Claims

1. A semiconductor device comprising:

a transistor formed on an insulating surface, said transistor including;

a semiconductor film having source and drain regions, a channel forming region between the source and drain regions,

a gate insulating film,

a gate electrode adjacent to the channel forming region having the gate insulating film therebetween;

a first organic resin film formed over the transistor;

a conductive film formed on the first organic resin film;

a second organic resin film formed on the conductive film; and

a pixel electrode formed on the second organic resin film.

2. A device according to claim 1 further comprising:

a first inorganic layer formed below said first organic resin film; and

a second inorganic layer formed on said first inorganic layer,

wherein each of said first and second inorganic layers comprises a material selected from the group consisting of silicon oxide and silicon nitride.

3. A device according to claim 1, wherein said semiconductor film comprises crystalline silicon.

10. A device according to claim 1, wherein each of the conductive film and the pixel electrode is a transparent conductive film.

11. A device according to claim 1, wherein each of the conductive film and the pixel electrode comprises at least one selected from the group consisting of ITO (indium tin oxide) and SnO₂.

4. A display device comprising:

a transistor formed on an insulating surface, said transistor including;

a semiconductor film having source and drain regions, a channel forming region between said source and drain regions,

a gate insulating film,

a gate electrode adjacent to said channel forming region having the gate insulating film therebetween;

a first organic resin film formed over said transistor;

a common electrode formed on said first organic resin film;

a second organic resin film formed on said common electrode;

a pixel electrode formed on said second organic resin film.

5. A device according to claim 4 further comprising:

a first inorganic layer formed below said first organic resin film; and

a second inorganic layer formed on said first inorganic layer,

wherein each of said first and second inorganic layers comprises a material selected from the group consisting of silicon oxide and silicon nitride.

6. A device according to claim 4, wherein said semiconductor film comprises crystalline silicon.

12. A device according to claim 4, wherein each of the common electrode and the pixel electrode is a transparent conductive film.

13. A device according to claim 4, wherein each of the common electrode and the pixel electrode comprises at least one selected from the group consisting of ITO (indium tin oxide) and SnO₂.

7. A semiconductor device comprising:

a transistor formed over an insulating surface, said transistor including source and drain regions, a channel forming region between the source and drain regions, and a gate electrode adjacent to the channel forming region having a gate insulating film therebetween;

a first organic resin film formed over the transistor;

a conductive film on the first organic resin film;

a second organic resin film on the conductive film; and

a pixel electrode formed on the second organic resin film.

8. A device according to claim 7 further comprising:

a first inorganic layer formed below said first organic resin film; and

a second inorganic layer formed on said first inorganic layer,

wherein each of said first and second inorganic layers comprises a material selected from the group consisting of silicon oxide and silicon nitride.

9. A device according to claim 7 wherein said source and drain regions, and said channel forming region are formed in a crystalline semiconductor island.

14. A device according to claim 7, wherein each of the conductive film and the pixel electrode is a transparent conductive film.

15. A device according to claim 7, wherein each of the conductive film and the pixel electrode comprises at least one selected from the group consisting of ITO (indium tin oxide) and SnO₂.