Display device, display module, and electronic device

Patent metadata

Field	Value
Publication number	US-9964799-B2
Application number	US-201615066040-A
Country	US
Kind code	B2
Filing date	Mar 10, 2016
Priority date	Mar 17, 2015
Publication date	May 8, 2018
Grant date	May 8, 2018

Abstract

A reflective liquid crystal display device capable of favorable display is provided. A reflective liquid crystal display device having a high aperture ratio is provided. A reflective film is provided on the counter substrate side. An oxide conductor film is used as an electrode of a capacitor or a liquid crystal element. Specifically, a display device includes a transistor, an insulating film, a capacitor, a liquid crystal element, and a reflective film. The transistor is electrically connected to the capacitor and the liquid crystal element. The transistor includes an oxide semiconductor film. The capacitor transmits visible light. The capacitor or the liquid crystal element includes an oxide conductor film as at least one of a pair of electrodes. The oxide semiconductor film is opposite to the oxide conductor film with the insulating film therebetween. The reflective film is opposite to the transistor with the liquid crystal element therebetween.

First claim

What is claimed is:

1. A display device comprising:
a transistor comprising an oxide semiconductor film;
an insulating film over the transistor;
a liquid crystal element electrically connected to the transistor, over the insulating film, the liquid crystal element comprising a pixel electrode, a common electrode, and a liquid crystal layer;
a color filter layer;
a reflective film over the liquid crystal element and the color filter layer; and
a counter substrate over the reflective film,
wherein the pixel electrode of the liquid crystal element comprises a first oxide conductor film comprising gallium, and
wherein the reflective film is positioned between the common electrode of the liquid crystal element and the counter substrate, and between the color filter layer and the counter substrate.

2. The display device according to claim 1 ,
wherein the oxide semiconductor film comprises an In-M-Zn oxide, and
wherein the M is Al, Ti, Ga, Y, Zr, La, Ce, Nd, Sn, or Hf.

3. The display device according to claim 1 ,
wherein the transistor comprises a first gate electrode and a second gate electrode with the oxide semiconductor film therebetween, and
wherein one of the first gate electrode and the second gate electrode comprises a second oxide conductor film comprising gallium.

4. The display device according to claim 1 , further comprising a touch sensor.

5. A display module comprising:
the display device according to claim 1 ; and
a flexible printed circuit.

6. An electronic device comprising:
the display device according to claim 1 ;
a flexible printed circuit; and
at least one of an antenna, a battery, a housing, a speaker, a microphone, an operation switch, and an operation button.

7. A display device comprising:
a transistor comprising an oxide semiconductor film;
an insulating film over the transistor;
a capacitor electrically connected to the transistor;
a liquid crystal element electrically connected to the transistor, over the insulating film, the liquid crystal element comprising a pixel electrode, a common electrode, and a liquid crystal layer;
a color filter layer;
a reflective film over the liquid crystal element and the color filter layer; and
a counter substrate over the reflective film,
wherein the pixel electrode of the liquid crystal element comprises a first oxide conductor film comprising an In—Ga—Zn oxide,
wherein one of a pair of electrodes of the capacitor comprises a second oxide conductor film comprising an In—Ga—Zn oxide, and
wherein the reflective film is positioned between the common electrode of the liquid crystal element and the counter substrate, and between the color filter layer and the counter substrate.

8. The display device according to claim 7 ,
wherein the oxide semiconductor film comprises an In-M-Zn oxide, and
wherein the M is Al, Ti, Ga, Y, Zr, La, Ce, Nd, Sn, or Hf.

9. The display device according to claim 7 ,
wherein the transistor comprises a first gate electrode and a second gate electrode with the oxide semiconductor film therebetween, and
wherein one of the first gate electrode and the second gate electrode comprises a third oxide conductor film comprising an In—Ga—Zn oxide.

10. The display device according to claim 7 , further comprising a touch sensor.

11. A display module comprising:
the display device according to claim 7 ; and
a flexible printed circuit.

12. An electronic device comprising:
the display device according to claim 7 ;
a flexible printed circuit; and
at least one of an antenna, a battery, a housing, a speaker, a microphone, an operation switch, and an operation button.

13. The display device according to claim 1 , wherein the common electrode of the liquid crystal element is electrically connected to the reflective film.

14. The display device according to claim 1 , wherein the common electrode of the liquid crystal element comprises a second oxide conductor film comprising an In—Ga—Zn oxide.

15. The display device according to claim 1 , further comprising a coloring film between the reflective film and the common electrode of the liquid crystal element.

16. The display device according to claim 7 , wherein the common electrode of the liquid crystal element is electrically connected to the reflective film.

17. The display device according to claim 7 , wherein the common electrode of the liquid crystal element comprises a third oxide conductor film comprising an In—Ga—Zn oxide.

18. The display device according to claim 7 , further comprising a coloring film between the reflective film and the common electrode of the liquid crystal element.

Assignees

• Semiconductor Energy Lab

Inventors

• Hirakata Yoshiharu

Classifications

• G02F2001/13356

  Physics · mapped topic

• G02F1/13338

  Input devices, e.g. touch panels · CPC title

• G02F1/133553 Primary

  Reflecting elements (associated to illuminating devices G02F1/133605) · CPC title

• G02F2001/133562

  Physics · mapped topic

• G02F1/13356

  characterised by the placement of the optical elements · CPC title