INPUT/OUTPUT DEVICE AND ELECTRONIC DEVICE

• US 20160349557A1
• Filed: 05/12/2016
• Published: 12/01/2016
• Est. Priority Date: 05/29/2015
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: WATANABE, Kazunori, KANEYASU, Makoto, SHISHIDO, Hideaki, KUSUNOKI, Koji, TOYOTAKA, Kouhei
• Granted Patent: US 10,139,663 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/134345 Subdivided pixels, e.g. for grey scale or redundancy
• 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 1/13624 having more than one switching element per pixel
• CPC Class Codes: G06F 2203/04108 Touchless 2D- digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface without distance measurement in the Z direction
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/041661 using detection at multiple resolutions, e.g. coarse and fine scanning; using detection within a limited area, e.g. object tracking window
• CPC Class Codes: G06F 3/04184 Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

An input/output device is provided. The input/output device includes a first pixel electrode, a second pixel electrode, a first common electrode, a second common electrode, a liquid crystal, a first insulating film, a second insulating film, and a transistor. The first common electrode can serve as one electrode of a sensor element. The second common electrode can serve as the other electrode of the sensor element. The transistor includes a first gate, a second gate, and a semiconductor layer. The pixel electrode, the common electrodes, and the second gate are positioned on different planes. The second gate contains one or more kinds of metal elements included in the semiconductor layer. The second gate, the pixel electrode, and the common electrodes preferably contain one or more kinds of metal elements included in the semiconductor layer.

Claims

1. An input/output device comprising:

a first pixel electrode;

a second pixel electrode;

a first common electrode;

a second common electrode;

a liquid crystal;

a first insulating film;

a second insulating film; and

a transistor,

wherein the first common electrode serves as one electrode of a sensor element,

wherein the second common electrode serves as the other electrode of the sensor element,

wherein the transistor comprises a first gate, a semiconductor layer over the first gate, and a second gate over the semiconductor layer,

wherein the semiconductor layer comprises a channel formation region that comprises an oxide semiconductor,

wherein the second gate comprises an oxide conductor,

wherein the oxide conductor comprises one or more kinds of metal elements comprised in the oxide semiconductor,

wherein the first insulating film is positioned over the second gate,

wherein the first pixel electrode, the second pixel electrode, the first common electrode, and the second common electrode are positioned over the first insulating film,

wherein the first pixel electrode overlaps with the first common electrode with the second insulating film positioned between the first pixel electrode and the first common electrode,

wherein the second pixel electrode overlaps with the second common electrode with the second insulating film positioned between the second pixel electrode and the second common electrode,

wherein the liquid crystal is positioned over the first pixel electrode, the second pixel electrode, the first common electrode, and the second common electrode,

wherein the first pixel electrode and the second pixel electrode are apart from each other and are positioned on a same plane, and

wherein the first common electrode and the second common electrode are apart from each other and are positioned on a same plane.

2. The input/output device according to claim 1, further comprising a second transistor,

wherein a source or a drain of one of the transistor and the second transistor is electrically connected to the first pixel electrode, and

wherein a source or a drain of the other of the transistor and the second transistor is electrically connected to the second pixel electrode.

3. The input/output device according to claim 1, wherein the transistor is positioned in a driver circuit portion.

4. The input/output device according to claim 1, wherein the second gate is electrically connected to the first gate.

5. The input/output device according to claim 1,

wherein the second insulating film is positioned over the first pixel electrode and the second pixel electrode, and

wherein the first common electrode and the second common electrode are positioned over the second insulating film.

6. The input/output device according to claim 1, wherein the first pixel electrode, the second pixel electrode, the first common electrode, and the second common electrode each comprise one or more kinds of metal elements comprised in the oxide semiconductor.

7. The input/output device according to claim 1, wherein the oxide semiconductor, the oxide conductor, the first pixel electrode, the second pixel electrode, the first common electrode, and the second common electrode each comprise an oxide comprising indium.

8. The input/output device according to claim 1, wherein the first pixel electrode, the second pixel electrode, the first common electrode, and the second common electrode each have a function of transmitting visible light.

9. The input/output device according to claim 1,

wherein the oxide semiconductor and the oxide conductor each comprise an In-M₁-Zn oxide, and

wherein the M₁ is Al, Ti, Ga, Y, Zr, La, Ce, Nd, Sn, or Hf.

10. The input/output device according to claim 1,

further comprising a first conductive film between the first insulating film and the first common electrode,

wherein the first conductive film has a lower resistivity than the first common electrode, and

wherein the first conductive film is electrically connected to the first common electrode.

11. The input/output device according to claim 10,

further comprising a second conductive film between the first insulating film and the second common electrode,

wherein the second conductive film has a lower resistivity than the second common electrode,

wherein the second conductive film is electrically connected to the second common electrode, and

wherein the first conductive film and the second conductive film are apart from each other and are positioned on a same plane.

12. The input/output device according to claim 11,

further comprising a light-blocking film,

wherein the light-blocking film overlaps with one of the first conductive film and the second conductive film with the liquid crystal positioned between the light-blocking film and the one of the first conductive film and the second conductive film.

13. An electronic device comprising:

the input/output device according to claim 1; and

an antenna, a battery, a housing, a speaker, a microphone, an operation switch, or an operation button.

14. A device comprising:

a first transistor;

a second transistor;

a first insulating film over the first transistor and the second transistor;

a first pixel electrode over the first insulating film;

a second pixel electrode over the first insulating film;

a first common electrode over the first insulating film;

a second common electrode over the first insulating film;

a second insulating film between the first pixel electrode and the first common electrode and between the second pixel electrode and the second common electrode;

a liquid crystal over the first pixel electrode, the second pixel electrode, the first common electrode, and the second common electrode,

wherein the first common electrode serves as one electrode of a sensor element, and

wherein the second common electrode serves as the other electrode of the sensor element.

15. The device according to claim 14, further comprising:

an auxiliary wiring in contact with the first common electrode,

wherein the auxiliary wiring has a lower resistivity than the first common electrode.

16. The device according to claim 14, further comprising:

a signal line under the first insulating film.

17. The device according to claim 14, wherein each of the first transistor and the second transistor comprises a channel formation region that comprises an oxide semiconductor.

18. The device according to claim 14, wherein each of the first transistor and the second transistor comprises a channel formation region that comprises indium, gallium and zinc.

19. The device according to claim 14,

wherein the first common electrode is located over the first pixel electrode, and

wherein the second common electrode is located over the second pixel electrode.

20. The device according to claim 14,

wherein the first common electrode is located under the first pixel electrode, and

wherein the second common electrode is located under the second pixel electrode.