Group-III element nitride semiconductor substrate
A Group-III element nitride semiconductor substrate includes: a first surface; and a second surface, wherein warping of a crystal plane of the first surface has a plurality of extremes.
1 . A Group-III element nitride semiconductor substrate, comprising:
a first surface; and
a second surface,
wherein warping of a crystal plane of the first surface has a plurality of extremes.
2 . The Group-III element nitride semiconductor substrate according to claim 1 , wherein warping of a crystal plane in a <11-20> direction passing through a center of the substrate in the crystal plane of the first surface, and warping of a crystal plane in a <1-100> direction perpendicular to the <11-20> direction and passing through the center of the substrate each have a plurality of extremes.
3 . The Group-III element nitride semiconductor substrate according to claim 1 , wherein a number of the extremes is 3 or more.
4 . The Group-III element nitride semiconductor substrate according to claim 1 , wherein the extremes have an interval of 3 mm or more between adjacent extremes.
5 . The Group-III element nitride semiconductor substrate according to claim 1 , wherein an off-angle variation of the Group-III element nitride semiconductor substrate as a whole is 0.40° or less.
6 . The Group-III element nitride semiconductor substrate according to claim 1 , wherein the Group-III element nitride semiconductor substrate has a diameter of 75 mm or more.
7 . A Group-III element nitride semiconductor substrate, comprising:
a first surface; and
a second surface,
wherein warping of a crystal plane in a <11-20> direction passing through a center of the substrate in the crystal plane of the first surface, and warping of a crystal plane in a <1-100> direction perpendicular to the <11-20> direction and passing through the center of the substrate each have 3 or more of extremes,
wherein the extremes have an interval of 3 mm or more between adjacent extremes,
wherein an off-angle variation of the Group-III element nitride semiconductor substrate as a whole is 0.40° or less, and
wherein the Group-III element nitride semiconductor substrate has a diameter of 75 mm or more.