Patent ID: 8228963

Claim:
A gallium nitride-based semiconductor optical device, comprising: a support base comprising a first gallium nitride-based semiconductor, a reference axis extending in a direction of one of an m-axis and an a-axis of the first gallium nitride-based semiconductor, a reference plane being orthogonal to the reference axis, the support base having a primary surface, the primary surface tilting with reference to the reference plane toward the other of the m-axis and the a-axis of the first gallium nitride-based semiconductor by a tilt angle in a range of 0.05 degree or more to less than 15 degrees; a first conductive type gallium nitride-based semiconductor region provided on the primary surface; a semiconductor epitaxial layer provided for an active layer on the first conductive type gallium nitride-based semiconductor region, the semiconductor epitaxial layer comprising a second gallium nitride-based semiconductor, the second gallium nitride-based semiconductor including indium as a constituent element, an indium content of the semiconductor epitaxial layer being more than 0.1, an m-plane and an a-plane of the second gallium nitride-based semiconductor tilting with reference to a normal axis, and the normal axis extending in a direction of a normal line of the primary surface.