Patent ID: 8536030

Claim:
A method of manufacturing a semipolar semiconductor crystal comprising a group-III-nitride (III-N), the method comprising: providing a substrate comprising sapphire (Al 2 O 3 ) having a first surface that intersects c-planes of the sapphire; forming a plurality of trenches in the first surface, each trench having a wall whose surface is substantially parallel to a c-plane of the substrate; epitaxially growing a (III-N) material in the trenches on the c-plane surfaces of their walls until the material overgrows the trenches to form a second surface, substantially parallel to the first surface; wherein the first and second surfaces are planar surfaces substantially parallel to crystallographic planes denoted respectively by first and second crystallographic notations in a pair of notations chosen from the group consisting of: {11-23}/{10-11}; {22-43}/{20-21}; {11-26}/{10-12}; and {10-11}/{11-21}.