Display device

• US 9,431,428 B2
• Filed: 02/19/2015
• Issued: 08/30/2016
• Est. Priority Date: 04/19/2013
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei
• Primary Examiner(s): Lebentritt, Michael
• Application Number:
  US14/626,011
• Publication Number:
  US 20150162360A1
• Time in Patent Office: 558 Days
• Field of Search: 257/347
• US Class Current: 1/1
• CPC Class Codes: B81B 2201/047 Optical MEMS not provided for in B81B2201/042 - B81B2201/045
• CPC Class Codes: B81B 2203/0163 Spring holders
• CPC Class Codes: B81B 2203/051 Translation according to an axis parallel to the substrate
• CPC Class Codes: B81B 2207/012 the micromechanical device and the control or processing electronics being separate parts in the same package
• CPC Class Codes: B81B 3/0083 Optical properties
• CPC Class Codes: B81B 7/008 MEMS characterised by an electronic circuit specially adapted for controlling or driving the same B81B7/0087 takes precedence; arrangements for starting, regulating, braking, or otherwise controlling an actuator H02N; control arrangements or circuits for visual indicators G09G3/00
• CPC Class Codes: G02B 26/02 for controlling the intensity of light G02B26/004 takes precedence
• CPC Class Codes: G02B 26/04 by periodically varying the intensity of light, e.g. using choppers shutters, diaphragms for cameras G03B9/00; devices for eliminating or reducing the effect of flicker in projection systems G03B21/40
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133723 Polyimide, polyamide-imide
• 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 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 29/24 including, apart from doping materials or other impurities, only semiconductor materials not provided for in groups H01L29/16, H01L29/18, H01L29/20, H01L29/22 including organic materials H10K99/00
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

A display device capable of operating at high speed and with low power consumption is provided. A miniaturized display device occupying a small area is also provided. The display device includes a support; a display portion which includes a pixel; a light-blocking unit which is in the support and includes a light-blocking layer having a first opening overlapping with at least part of the pixel, and a movable light-blocking layer blocking light passing through the first opening; a transistor which is electrically connected to the light-blocking unit and includes an oxide semiconductor film; and a capacitor electrically connected to the transistor.

Claims

1. A display device comprising:

a display element between a pair of electrodes; and

a MEMS shutter capable of moving to block light,

wherein the MEMS shutter is electrically connected to a switching element,

wherein the switching element comprises at least a transistor and a capacitor,

wherein the transistor comprises an oxide semiconductor film, and

wherein the capacitor comprises a conductive film, an insulating film, and one of the pair of electrodes.

2. The display device according to claim 1, wherein the display element is a liquid crystal element.

3. The display device according to claim 1, wherein one of the pair of electrodes is electrically connected to the transistor.

4. The display device according to claim 1, wherein the MEMS shutter comprises:

a first layer having an opening overlapping with at least part of the display element;

a second layer configured to block light passing through the opening; and

an actuator configured to move the second layer.

5. The display device according to claim 4, wherein the actuator is electrically connected to the transistor.

6. The display device according to claim 1, wherein the oxide semiconductor film and the conductive film are on a same surface.

7. The display device according to claim 1, wherein the oxide semiconductor film comprises at least one of In, Ga, and Zn.

8. The display device according to claim 1, wherein the conductive film comprises at least one of In, Ga, and Zn.

9. A display device comprising:

a display element between a pair of electrodes; and

a MEMS shutter capable of moving to block light,

wherein the MEMS shutter is electrically connected to a first switching element and a second switching element,

wherein the first switching element comprises at least a first transistor and a first capacitor,

wherein the second switching element comprises at least a second transistor and a second capacitor,

wherein the first transistor comprises a first oxide semiconductor film,

wherein the second transistor comprises a second oxide semiconductor film,

wherein the first capacitor comprises a first conductive film, a first insulating film, and one of the pair of electrodes, and

wherein the second capacitor comprises a second conductive film, a second insulating film, and the one of the pair of electrodes.

10. The display device according to claim 9, wherein the display element is a liquid crystal element.

11. The display device according to claim 9, wherein one of the pair of electrodes is electrically connected to the first transistor and the second transistor.

12. The display device according to claim 9, wherein the MEMS shutter comprises:

a first layer having an opening overlapping with at least part of the display element;

a second layer configured to block light passing through the opening; and

an actuator configured to move the second layer.

13. The display device according to claim 12, wherein the actuator is electrically connected to the first transistor and the second transistor.

14. The display device according to claim 9, wherein the first oxide semiconductor film, the second oxide semiconductor film, the first conductive film, and the second conductive film are on a same surface.

15. The display device according to claim 9, wherein each of the first oxide semiconductor film and the second oxide semiconductor film comprises at least one of In, Ga, and Zn.

16. The display device according to claim 9, wherein each of the first conductive film and the second conductive film comprises at least one of In, Ga, and Zn.

17. A semiconductor device comprising:

a first transistor comprising a first semiconductor film;

a second transistor comprising a second semiconductor film;

a capacitor; and

a MEMS shutter,

wherein the first transistor is electrically connected to the MEMS shutter,

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

wherein the capacitor is electrically connected to the other of source and drain of the second transistor.

18. The semiconductor device according to claim 17, wherein the second transistor is positioned over the first transistor.

19. The semiconductor device according to claim 17, wherein the second semiconductor film is an oxide semiconductor film.

20. The semiconductor device according to claim 19, wherein the oxide semiconductor film comprises at least one of In, Ga, and Zn.

21. The semiconductor device according to claim 17,

wherein the capacitor comprises a first conductive film, a second conductive film, and an insulating film,

wherein the first conductive film and the second semiconductor film are on a same surface, and

wherein the second conductive film is electrically connected to the other of source and drain of the second transistor.

22. The semiconductor device according to claim 17,

wherein the MEMS shutter is capable of moving to block light, and

wherein the MEMS shutter comprises:

a first layer having an opening;

a second layer configured to block light passing through the opening; and

an actuator configured to move the second layer.

23. The semiconductor device according to claim 22, wherein the actuator is electrically connected to the first transistor.