Liquid crystal display device

• US 9,904,127 B2
• Filed: 01/04/2017
• Issued: 02/27/2018
• Est. Priority Date: 12/05/2005
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Kimura, Hajime, Uochi, Hideki
• Primary Examiner(s): Wong, Tina
• Application Number:
  US15/397,813
• Publication Number:
  US 20170115538A1
• Time in Patent Office: 419 Days
• Field of Search: None
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/133371 Cells with varying thickness of the liquid crystal layer
• CPC Class Codes: G02F 1/133553 Reflecting elements associated to illuminating devices G02F1/133605
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/134372 for fringe field switching [FFS] where the common electrode is not patterned
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• 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 1/136222 Colour filters incorporated in the active matrix substrate
• 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 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 2201/121 common or background
• CPC Class Codes: G02F 2201/123 pixel
• CPC Class Codes: G02F 2201/124 interdigital

Abstract

It is an object of the present invention to apply a sufficient electrical field to a liquid crystal material in a horizontal electrical field liquid crystal display device typified by an FFS type. In a horizontal electrical field liquid crystal display, an electrical field is applied to a liquid crystal material right above a common electrode and a pixel electrode using plural pairs of electrodes rather than one pair of electrodes. One pair of electrodes includes a comb-shaped common electrode and a comb-shaped pixel electrode. Another pair of electrodes includes a common electrode provided in a pixel portion and the comb-shaped pixel electrode.

Claims

1. A semiconductor device comprising:

a first pixel comprising;

a first common electrode over an insulating surface;

a gate electrode over the insulating surface;

a common wiring in contact with a top surface of the first common electrode;

a gate insulating layer over the first common electrode, the gate electrode, and the common wiring;

a semiconductor layer over the gate insulating layer;

an insulating layer over the gate insulating layer and the semiconductor layer;

a pixel electrode over the insulating layer; and

a connection electrode over the insulating layer; and

a second pixel adjacent to the first pixel,

wherein the first common electrode comprises a region overlapping with the connection electrode and a region not overlapping with the connection electrode,

wherein the first common electrode is electrically connected to a second common electrode of the second pixel though the connection electrode,

wherein the first common electrode and the second common electrode are formed by processing a first transparent conductive layer,

wherein the gate electrode and the common wiring are formed by processing a second light-shielding conductive layer, and

wherein the pixel electrode and the connection electrode are formed by processing a third transparent conductive layer.

2. The semiconductor device according to claim 1, wherein each of the pixel electrode and the connection electrode is in contact with a top surface of the insulating layer.

3. The semiconductor device according to claim 1,

wherein the pixel electrode has a slit,

wherein the first common electrode overlaps with the slit,

wherein a width of the first common electrode is larger than a width of the slit, and

wherein the gate insulating layer is in contact with the top surface of the first common electrode in both sides of the common wiring.

4. A semiconductor device comprising:

a first pixel comprising;

a first common electrode over an insulating surface;

a gate electrode over the insulating surface;

a common wiring in contact with a top surface of the first common electrode;

a gate insulating layer over the first common electrode, the gate electrode, and the common wiring;

a semiconductor layer over the gate insulating layer;

an insulating layer over the gate insulating layer and the semiconductor layer;

a pixel electrode over the insulating layer; and

a connection electrode over the insulating layer; and

a second pixel adjacent to the first pixel,

wherein the first common electrode comprises a region overlapping with the connection electrode and a region not overlapping with the connection electrode,

wherein the first common electrode is electrically connected to a second common electrode of the second pixel though the connection electrode,

wherein the first common electrode and the second common electrode comprise a transparent conductive material and are in contact with the insulating surface,

wherein the gate electrode and the common wiring comprise a light-shielding conductive material and are in contact with a bottom surface of the gate insulating layer, and

wherein the pixel electrode and the connection electrode comprise a transparent conductive material.

5. The semiconductor device according to claim 4,

wherein the transparent conductive material comprised in the first common electrode and the second common electrode is an indium tin oxide, and

wherein the transparent conductive material comprised in the pixel electrode and the connection electrode is an indium tin oxide.

6. The semiconductor device according to claim 4, wherein each of the pixel electrode and the connection electrode is in contact with a top surface of the insulating layer.

7. The semiconductor device according to claim 4,

wherein the pixel electrode has a slit,

wherein the first common electrode overlaps with the slit,

wherein a width of the first common electrode is larger than a width of the slit, and

wherein the gate insulating layer is in contact with the top surface of the first common electrode in both sides of the common wiring.

8. A semiconductor device comprising:

a first pixel comprising;

a first common electrode over an insulating surface;

a gate electrode over the insulating surface;

a common wiring in contact with a top surface of the first common electrode;

a gate insulating layer over the first common electrode, the gate electrode, and the common wiring;

a semiconductor layer over the gate insulating layer;

a first insulating layer over the gate insulating layer and the semiconductor layer;

a pixel electrode over the first insulating layer;

a connection electrode over the first insulating layer; and

a second insulating layer over the pixel electrode; and

a second pixel adjacent to the first pixel,

wherein the first common electrode comprises a region overlapping with the connection electrode and a region not overlapping with the connection electrode,

wherein the first common electrode is electrically connected to a second common electrode of the second pixel though the connection electrode,

wherein the first common electrode and the second common electrode are formed by processing a first transparent conductive layer,

wherein the gate electrode and the common wiring are formed by processing a second light-shielding conductive layer,

wherein the pixel electrode and the connection electrode are formed by processing a third transparent conductive layer,

wherein the second insulating layer is capable of adjusting cell gap, and

wherein the second insulating layer comprise a region overlapping with the common wiring.

9. The semiconductor device according to claim 8, wherein each of the pixel electrode and the connection electrode is in contact with a top surface of the first insulating layer.

10. The semiconductor device according to claim 8,

wherein the pixel electrode has a slit,

wherein the first common electrode overlaps with the slit,

wherein a width of the first common electrode is larger than a width of the slit, and

wherein the gate insulating layer is in contact with the top surface of the first common electrode in both sides of the common wiring.