Oxide semiconductor

Patent metadata

Field	Value
Publication number	US-9771272-B2
Application number	US-201615180695-A
Country	US
Kind code	B2
Filing date	Jun 13, 2016
Priority date	Mar 19, 2013
Publication date	Sep 26, 2017
Grant date	Sep 26, 2017

Abstract

To provide an oxide semiconductor with a novel structure. Such an oxide semiconductor is composed of an aggregation of a plurality of InGaZnO 4 crystals each of which is larger than or equal to 1 nm and smaller than or equal to 3 nm, and in the oxide semiconductor, the plurality of InGaZnO 4 crystals have no orientation. Alternatively, such an oxide semiconductor is such that a diffraction pattern like a halo pattern is observed by electron diffraction measurement performed by using an electron beam with a probe diameter larger than or equal to 300 nm, and that a diffraction pattern having a plurality of spots arranged circularly is observed by electron diffraction measurement performed by using an electron beam with a probe diameter larger than or equal to 1 nm and smaller than or equal to 30 nm.

First claim

What is claimed is:

1. An oxide semiconductor comprising:
an aggregation of a plurality of crystals,
wherein the plurality of crystals includes indium,
wherein each of the plurality of crystals has a size larger than or equal to 1 nm and smaller than or equal to 3 nm, and
wherein half widths at half maximum of a diffraction peak of the oxide semiconductor is 0.4 nm −1 to 0.6 nm −1 .

2. The oxide semiconductor according to claim 1 ,
wherein the plurality of crystals has no orientation, and
wherein a boundary between the plurality of crystals is not observed in a TEM image of the oxide semiconductor.

3. The oxide semiconductor according to claim 1 ,
wherein the plurality of crystals further includes gallium and zinc.

4. The oxide semiconductor according to claim 3 ,
wherein the plurality of crystals is InGaZnO 4 crystals.

5. The oxide semiconductor according to claim 1 ,
wherein a diffraction pattern having a plurality of spots is observed when an electron diffraction measurement is performed on the oxide semiconductor by using an electron beam with a probe diameter larger than or equal to 1 nm and smaller than or equal to 30 nm, and
wherein a diffraction pattern with no spot is observed when an electron diffraction measurement is performed on the oxide semiconductor by using an electron beam with a probe diameter larger than or equal to 300 nm.

6. The oxide semiconductor according to claim 5 ,
wherein the plurality of spots is circularly arranged.

7. An oxide semiconductor comprising:
indium,
wherein a diffraction pattern having a plurality of spots circularly arranged is observed when an electron diffraction measurement is performed on the oxide semiconductor by using an electron beam with a probe diameter larger than or equal to 1 nm and smaller than or equal to 30 nm,
wherein a diffraction pattern with no spot is observed when an electron diffraction measurement is performed on the oxide semiconductor by using an electron beam with a probe diameter larger than or equal to 300 nm,
wherein a grain boundary is not observed in a TEM image of the oxide semiconductor, and
wherein half widths at half maximum of a diffraction peak of the oxide semiconductor is 0.4 nm −1 to 0.6 nm −1 .

8. The oxide semiconductor according to claim 7 , further comprising gallium and zinc.

9. The oxide semiconductor according to claim 8 ,
wherein the plurality of spots circularly arranged is derived from InGaZnO 4 crystals having no orientation.

Assignees

• Semiconductor Energy Lab

Inventors

• Yamazaki Shunpei
• Takahashi Masahiro
• Kimizuka Noboru

Classifications

• C01P2004/04

  obtained by TEM, STEM, STM or AFM · CPC title

• C01P2002/77

  by unit-cell parameters, atom positions or structure diagrams · CPC title

• C01G15/00 Primary

  Compounds of gallium, indium or thallium · CPC title

• C01P2002/70

  defined by measured X-ray, neutron or electron diffraction data · CPC title

• C01P2006/10

  Solid density · CPC title