Metal oxide film and method for forming metal oxide film

Patent metadata

Field	Value
Publication number	US-11978742-B2
Application number	US-202318137032-A
Country	US
Kind code	B2
Filing date	Apr 20, 2023
Priority date	Nov 8, 2012
Publication date	May 7, 2024
Grant date	May 7, 2024

Abstract

A metal oxide film including a crystal part and having highly stable physical properties is provided. The size of the crystal part is less than or equal to 10 nm, which allows the observation of circumferentially arranged spots in a nanobeam electron diffraction pattern of the cross section of the metal oxide film when the measurement area is greater than or equal to 5 nmφ and less than or equal to 10 nmφ.

First claim

The invention claimed is:

1. A display device comprising:
an insulating film, a gate electrode, an oxide semiconductor layer, and a gate insulating film between the gate electrode and the oxide semiconductor layer,
wherein a plurality of circumferentially distributed spots are observable in a nanobeam electron diffraction pattern of the oxide semiconductor layer,
wherein the plurality of circumferentially distributed spots do not have regularity that represents crystal parts aligned with a specific plane,
wherein the oxide semiconductor layer is in contact with a top surface of the insulating film,
wherein the insulating film comprises silicon oxide,
wherein the gate electrode comprises at least one element selected from aluminum, chromium, copper, tantalum, titanium, molybdenum, and tungsten, and
wherein the gate insulating film comprises silicon oxide.

2. The display device according to claim 1 , wherein, when the oxide semiconductor layer is irradiated with electron beam whose beam diameter is converged to 1 nmφ for a minute, change in the electron diffraction pattern before and after the irradiation does not occur.

3. The display device according to claim 1 ,
wherein the oxide semiconductor layer comprises carbon, and
wherein a concentration of carbon is less than 4×10 21 atoms/cm 3 .

4. The display device according to claim 1 ,
wherein the oxide semiconductor layer comprises hydrogen, and
wherein a concentration of hydrogen is less than 1×10 22 atoms/cm 3 .

5. The display device according to claim 1 , wherein the nanobeam electron diffraction pattern is measured using electron beam whose beam diameter is 1 nmφ.

6. The display device according to claim 1 ,
wherein the oxide semiconductor layer includes a plurality of crystals,
wherein surface orientations of the plurality of crystals are random, and
wherein a crystalline peak corresponding to the plurality of crystals is not observable in an XRD spectrum with respect to a region of the oxide semiconductor layer.

7. The display device according to claim 6 ,
wherein a size of each of the plurality of crystals is greater than or equal to 1 nm and smaller than or equal to 10 nm.

8. A display device comprising:
an insulating film, an oxide semiconductor layer over the insulating film, a gate insulating film over the oxide semiconductor layer, and a gate electrode over the gate insulating film,
wherein a plurality of circumferentially distributed spots are observable in a nanobeam electron diffraction pattern of the oxide semiconductor layer,
wherein the plurality of circumferentially distributed spots do not have regularity that represents crystal parts aligned with a specific plane,
wherein the insulating film comprises silicon oxide,
wherein the gate electrode comprises at least one element selected from aluminum, chromium, copper, tantalum, titanium, molybdenum, and tungsten, and
wherein the gate insulating film comprises silicon oxide.

9. The display device according to claim 8 ,
wherein, when the oxide semiconductor layer is irradiated with electron beam whose beam diameter is converged to 1 nmφ for a minute, change in the electron diffraction pattern before and after the irradiation does not occur.

10. The display device according to claim 8 ,
wherein the oxide semiconductor layer comprises carbon, and
wherein a concentration of carbon is less than 4×10 21 atoms/cm 3 .

11. The display device according to claim 8 ,
wherein the oxide semiconductor layer comprises hydrogen, and
wherein a concentration of hydrogen is less than 1×10 22 atoms/cm 3 .

12. The display device according to claim 8 , wherein the nanobeam electron diffraction pattern is measured using electron beam whose beam diameter is 1 nmφ.

13. The display device according to claim 8 ,
wherein the oxide semiconductor layer includes a plurality of crystals,
wherein surface orientations of the plurality of crystals are random, and
wherein a crystalline peak corresponding to the plurality of crystals is not observable in an XRD spectrum with respect to a region of the oxide semiconductor layer.

14. The display device according to claim 13 , wherein a size of each of the plurality of crystals is greater than or equal to 1 nm and smaller than or equal to 10 nm.

15. A display device comprising:
a first transistor, a second transistor, a light-emitting element, and a capacitor,
wherein one of a source and a drain of the first transistor is electrically connected to a gate of the second transistor,
wherein the gate of the second transistor is electrically connected to one of a source and a drain of the second transistor through the capacitor,
wherein the other of the source and the drain of the second transistor is electrically connected to the light-emitting element,
wherein at least one of the first transistor and the second transistor comprises a gate electrode, an oxide semiconductor layer, and a gate insulating film between the gate electrode and the oxide semiconductor layer,
wherein a plurality of circumferentially distributed spots are observable in a nanobeam electron diffraction pattern of the oxide semiconductor layer,
wherein the plurality of circumferentially distributed spots do not have regularity that represents crystal parts aligned with a specific plane,
wherein the oxide semiconductor layer is in contact with a top surface of an insulating film,
wherein the insulating film comprises silicon oxide,
wherein the gate electrode comprises at least one element selected from aluminum, chromium, copper, tantalum, titanium, molybdenum, and tungsten, and
wherein the gate insulating film comprises silicon oxide.

16. The display device according to claim 15 , wherein, when the oxide semiconductor layer is irradiated with electron beam whose beam diameter is converged to 1 nmφ for a minute, change in the electron diffraction pattern before and after the irradiation does not occur.

17. The display device according to claim 15 ,
wherein the oxide semiconductor layer comprises carbon, and
wherein a concentration of carbon is less than 4×10 21 atoms/cm 3 .

18. The display device according to claim 15 ,
wherein the oxide semiconductor layer comprises hydrogen, and
wherein a concentration of hydrogen is less than 1×10 22 atoms/cm 3 .

19. The display device according to claim 15 , wherein the nanobeam electron diffraction pattern is measured using electron beam whose beam diameter is 1 nmφ.

20. The display device according to claim 15 ,
wherein the oxide semiconductor layer includes a plurality of crystals,
wherein surface orientations of the plurality of crystals are random, and
wherein a crystalline peak corresponding to the plurality of crystals is not observable in an XRD spectrum with respect to a region of the oxide semiconductor layer.

21. The display device according to claim 20 , wherein a size of each of the plurality of crystals is greater than or equal to 1 nm and smaller than or equal to 10 nm.

22. A display device comprising:
a first transistor, a second transistor, a light-emitting element, and a capacitor,
wherein one of a source and a drain of the first transistor is electrically connected to a gate of the second transistor,
wherein the gate of the second transistor is electrically connected to one of a source and a drain of the second transistor through the capacitor,
wherein the other of the source and the drain of the second transistor is electrically connected t

Assignees

• Semiconductor Energy Lab

Inventors

• Takahashi Masahiro
• Hirohashi Takuya
• Tsubuku Masashi
• Ishihara Noritaka
• Oota Masashi

Classifications

• H10P14/3434

  being oxide semiconductor materials (Group IIB-VIA semiconductor materials H10P14/3424) · CPC title

• H10P14/3426 Primary

  Oxides · CPC title

• H10P14/2922

  being non-crystalline insulating materials, e.g. glass or polymers · CPC title

• H10P14/2901

  Materials · CPC title

• H10P14/22

  using physical deposition, e.g. vacuum deposition or sputtering · CPC title