Light-emitting device

• US 9,230,996 B2
• Filed: 12/23/2014
• Issued: 01/05/2016
• Est. Priority Date: 12/27/2013
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Miyake, Hiroyuki, Koezuka, Junichi, Jintyou, Masami, Shima, Yukinori, Yamazaki, Shunpei
• Primary Examiner(s): TAYLOR, EARL N
• Application Number:
  US14/580,949
• Publication Number:
  US 20150187818A1
• Time in Patent Office: 378 Days
• Field of Search: 257/43
• US Class Current: 1/1
• 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 27/1237 with a different composition, shape, layout or thickness of the gate insulator in different devices
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1251 comprising TFTs having a different architecture, e.g. top- and bottom gate TFTs
• 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
• CPC Class Codes: H10K 59/1213 the pixel elements being TFTs

Abstract

A light-emitting device capable of suppressing variation in luminance among pixels is provided. A light-emitting device includes a pixel and first and second circuits. The first circuit has a function of generating a signal including a value of current extracted from the pixel. The second circuit has a function of correcting an image signal by the signal. The pixel includes at least a light-emitting element and first and second transistors. The first transistor has a function of controlling supply of the current to the light-emitting element by the image signal. The second transistor has a function of controlling extraction of the current from the pixel. A semiconductor film of each of the first and second transistors includes a first semiconductor region overlapping with a gate, a second semiconductor region in contact with a source or a drain, and a third semiconductor region between the first and second semiconductor regions.

Claims

1. A light-emitting device comprising:

a pixel comprising a light-emitting element, a first transistor and a second transistor;

a first circuit configured to generate a signal including a value of current extracted from the pixel; and

a second circuit configured to correct an image signal by the signal,

wherein the first transistor is configured to control supply of current to the light-emitting element by the image signal,

wherein the second transistor is configured to control extraction of current from the pixel, and

wherein a semiconductor film of each of the first transistor and the second transistor comprises;

a first semiconductor region overlapping with a gate electrode;

a second semiconductor region in contact with a source electrode or a drain electrode; and

a third semiconductor region containing higher concentration of hydrogen than the first semiconductor region and the second semiconductor region between the first semiconductor region and the second semiconductor region.

2. The light-emitting device according to claim 1, wherein the semiconductor film is an oxide semiconductor film.

3. The light-emitting device according to claim 2,

wherein the oxide semiconductor film contains indium, zinc, and M, and

wherein M is Mg, Al, Ti, Ga, Y, Zr, La, Ce, Nd, or Hf.

4. An electronic device comprising the light-emitting device according to claim 1, a microphone, and an operation key.

5. A light-emitting device comprising:

a wiring;

a first transistor comprising a first semiconductor film, and a first gate electrode and a second gate electrode overlapping with each other with the first semiconductor film therebetween;

a second transistor comprising a second semiconductor film;

a first capacitor configured to hold a potential difference between one of a first source electrode and a first drain electrode of the first transistor and the first gate electrode;

a second capacitor configured to hold a potential difference between the one of the first source electrode and the first drain electrode of the first transistor and the second gate electrode; and

a light-emitting element supplied with drain current of the first transistor;

wherein the second transistor is configured to control conduction between the second gate electrode and the wiring,

wherein the first semiconductor film comprises;

a first semiconductor region overlapping with the first gate electrode;

a second semiconductor region in contact with the first source electrode or the first drain electrode of the first transistor; and

a third semiconductor region containing higher concentration of hydrogen than the first semiconductor region and the second semiconductor region between the first semiconductor region and the second semiconductor region, and

wherein the second semiconductor film comprises;

a fourth semiconductor region overlapping with a third gate electrode of the second transistor;

a fifth semiconductor region in contact with a second source electrode or a second drain electrode of the second transistor; and

a sixth semiconductor region containing higher concentration of hydrogen than the fourth semiconductor region and the fifth semiconductor region between the fourth semiconductor region and the fifth semiconductor region.

6. The light-emitting device according to claim 5, wherein the first semiconductor film and the second semiconductor film are each an oxide semiconductor film.

7. The light-emitting device according to claim 6,

wherein the oxide semiconductor film contains indium, zinc, and M, and

wherein M is Mg, Al, Ti, Ga, Y, Zr, La, Ce, Nd, or Hf.

8. An electronic device comprising the light-emitting device according to claim 5, a microphone, and an operation key.

9. A light-emitting device comprising:

a first wiring and a second wiring;

a capacitor;

a light-emitting element;

a first transistor configured to control conduction between the first wiring and a first electrode of the capacitor;

a second transistor configured to control conduction between the second wiring and a gate electrode of a fifth transistor;

a third transistor configured to control conduction between the first electrode of the capacitor and the gate electrode of the fifth transistor;

a fourth transistor configured to control conduction between one of a source electrode and a drain electrode of the fifth transistor and an anode of the light-emitting element; and

the fifth transistor,

wherein a second electrode of the capacitor is electrically connected to the one of the source electrode and the drain electrode of the fifth transistor, and

wherein a semiconductor film of each of the first transistor, the second transistor, the third transistor, the fourth transistor, and the fifth transistor comprises;

a first semiconductor region overlapping with a gate electrode;

a second semiconductor region in contact with a source electrode or a drain electrode; and

a third semiconductor region containing higher concentration of hydrogen than the first semiconductor region and the second semiconductor region between the first semiconductor region and the second semiconductor region.

10. The light-emitting device according to claim 9, wherein the semiconductor film is an oxide semiconductor film.

11. The light-emitting device according to claim 10,

wherein the oxide semiconductor film contains indium, zinc, and M, and

wherein M is Mg, Al, Ti, Ga, Y, Zr, La, Ce, Nd, or Hf.

12. An electronic device comprising the light-emitting device according to claim 9, a microphone, and an operation key.

13. A light-emitting device comprising:

a first wiring, a second wiring, and a third wiring;

a capacitor;

a light-emitting element;

a first transistor configured to control conduction between the first wiring and a first electrode of the capacitor;

a second transistor configured to control conduction between the second wiring and a gate electrode of a fifth transistor;

a third transistor configured to control conduction between the first electrode of the capacitor and the gate electrode of the fifth transistor;

a fourth transistor configured to control conduction between one of a source electrode and a drain electrode of the fifth transistor and the third wiring; and

the fifth transistor,

wherein a second electrode of the capacitor is electrically connected to the one of the source electrode and the drain electrode of the fifth transistor and an anode of the light-emitting element, and

wherein a semiconductor film of each of the first transistor, the second transistor, the third transistor, the fourth transistor, and the fifth transistor comprises;

a first semiconductor region overlapping with a gate electrode;

a second semiconductor region in contact with a source electrode or a drain electrode; and

a third semiconductor region containing higher concentration of hydrogen than the first semiconductor region and the second semiconductor region between the first semiconductor region and the second semiconductor region.

14. The light-emitting device according to claim 13, wherein the semiconductor film is an oxide semiconductor film.

15. The light-emitting device according to claim 14,

wherein the oxide semiconductor film contains indium, zinc, and M, and

wherein M is Mg, Al, Ti, Ga, Y, Zr, La, Ce, Nd, or Hf.

16. An electronic device comprising the light-emitting device according to claim 13, a microphone, and an operation key.