β-Ga2O3 single-crystal substrate

Patent metadata

Field	Value
Publication number	US-10196756-B2
Application number	US-201515322848-A
Country	US
Kind code	B2
Filing date	Jun 29, 2015
Priority date	Jun 30, 2014
Publication date	Feb 5, 2019
Grant date	Feb 5, 2019

Abstract

A β-Ga2O3-based single-crystal substrate includes a β-Ga2O3-based single crystal, and a principal surface being a plane parallel to a b-axis of the β-Ga2O3-based single crystal. A maximum value of Δω on an arbitrary straight line on the principal surface that passes through a center of the principal surface is not more than 0.7264. The Δω is a difference between a maximum value and a minimum value of values obtained by subtracting ωa from ωs at each of measurement positions, where ωs represents an angle defined by an X-ray incident direction and the principal surface at a peak position of an X-ray rocking curve on the straight line and ωa represents an angle on an approximated straight line obtained by using least-squares method to linearly approximate a curve representing a relationship between the ωs and the measurement positions thereof.

First claim

The invention claimed is:

1. A β-Ga 2 O 3 -based single-crystal substrate, comprising:
a β-Ga 2 O 3 -based single crystal; and
a principal surface being a plane parallel to a b-axis of the β-Ga 2 O 3 -based single crystal, wherein the maximum value of Δω on an arbitrary straight line on the principal surface that passes through the center of the principal surface is not more than 0.7264, and

wherein the Δω is the difference between the maximum value and the minimum value of values obtained by subtracting ωa from ωs at each of measurement positions, where ωs represents an angle defined by an X-ray incident direction and the principal surface at a peak position of an X-ray rocking curve on the straight line and ωa represents an angle on an approximated straight line obtained by using least-squares method to linearly approximate a curve representing a relationship between the ωs and the measurement positions thereof, wherein the β-Ga 2 O 3 -based single-crystal substrate comprises a dopant, wherein the dopant is a Group IV element.

2. A β-Ga 2 O 3 -based single-crystal substrate, comprising:
a β-Ga 2 O 3 -based single crystal; and
a principal surface being a plane parallel to a b-axis of the β-Ga 2 O 3 -based single crystal, wherein the maximum value of α on an arbitrary straight line on the principal surface that passes through the center of the principal surface is not more than 0.141, and

wherein the α is an average value of absolute values obtained by subtracting ωa from ωs at each of measurement positions, where ωs represents an angle defined by an X-ray incident direction and the principal surface at a peak position of an X-ray rocking curve on the straight line and ωa represents an angle on an approximated straight line obtained by using least-squares method to linearly approximate a curve representing a relationship between the ωs and the measurement positions thereof, wherein the β-Ga 2 O 3 -based single-crystal substrate comprises a dopant, wherein the dopant is a Group IV element.

3. The β-Ga 2 O 3 -based single-crystal substrate according to claim 1 , wherein Δω on a straight line perpendicular to the b-axis of the β-Ga 2 O 3 -based single crystal is a maximum among the Δω on the arbitrary straight line.

4. The β-Ga 2 O 3 -based single-crystal substrate according to claim 2 , wherein α on a straight line perpendicular to the b-axis of the β-Ga 2 O 3 -based single crystal is a maximum among the α on the arbitrary straight line.

5. The β-Ga 2 O 3 -based single-crystal substrate according to claim 1 , wherein the dopant is Sn or Si.

6. The β-Ga 2 O 3 -based single-crystal substrate according to claim 1 , wherein the principal surface is a (−201) plane, a (101) plane or a (001) plane.

7. The β-Ga 2 O 3 -based single-crystal substrate according to claim 1 , wherein the substrate is cut out from a flat-plate-shaped β-Ga 2 O 3 -based single crystal grown in the b-axis direction.

8. The β-Ga 2 O 3 -based single-crystal substrate according to claim 1 , wherein the substrate comprises no twinning plane or a region that does not include a twinning plane that is not less than 2 inches in a maximum width in a direction perpendicular to an intersection line between the twinning plane and the principal surface.

Assignees

• Tamura Seisakusho Kk
• Koha Co Ltd

Inventors

• Watanabe Shinya
• Koshi Kimiyoshi
• Yamaoka Yu
• Iizuka Kazuyuki
• Takizawa Masaru
• Masui Takekazu

Classifications

• C30B15/34

  Edge-defined film-fed crystal-growth using dies or slits · CPC title

• C01P2002/77

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

• C01G15/00

  Compounds of gallium, indium or thallium · CPC title

• C30B29/16 Primary

  Oxides · CPC title