Group III nitride crystal, group III nitride semiconductor, group III nitride substrate, and method for producing group III nitride crystal
AssigneePanasonic Intellectual Property Management Co., Ltd.
InventorsAkio Ueta, Hiroshi Ohno
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Abstract
A group III nitride crystal substrate has a main surface and a back surface opposite to the main surface. The average dislocation density of the main surface and the average dislocation density of the back surface are less than or equal to 6.0×105 cm−2. Furthermore, the difference between the average dislocation density of the main surface and the average dislocation density of the back surface is less than or equal to 5.0×104 cm−2. The warpage of the crystal axis of the main surface has a radius of curvature of more than or equal to 30 m.
Claims13
A group III nitride crystal comprising:
- a main surface;
- and
- a back surface opposite to the main surface,
- wherein the main surface has an average dislocation density of less than or equal to 6.0×105 cm−2, and the back surface has an average dislocation density of less than or equal to 6.0×105 cm−2;
- a difference between the average dislocation density of the main surface and the average dislocation density of the back surface is less than or equal to 5.0×104 cm−2;
- and
- a warpage of a crystal axis of the main surface has a radius of curvature of more than or equal to 30 m.
A method for producing a group III nitride crystal, the method comprising:
- a preparation step of preparing a group III nitride seed substrate containing Na;
- and
- a growth step of growing a group III nitride crystal on the group III nitride seed substrate by vapor phase growth,
- wherein a start temperature of the growth step is 950° C. or higher and 970° C. or lower;
- and
- growth of the group III nitride crystal in the growth step is performed at a temperature of 950° C. or higher and 1,020° C. or lower.
A group III nitride crystal produced by a method comprising:
- a preparation step of preparing a group III nitride seed substrate containing Na;
- and
- a growth step of growing a group III nitride crystal on the group III nitride seed substrate by vapor phase growth,
- wherein a start temperature of the growth step is 950° C. or higher and 970° C. or lower;
- and
- growth of the group III nitride crystal in the growth step is performed at a temperature of 950° C. or higher and 1,020° C. or lower.
Dependencies are inferred from the claim text.