Patent ID: 8488642

Claim:
A gallium nitride based semiconductor light-emitting device comprising: a semiconductor region of a gallium nitride based semiconductor; an InGaN layer provided directly on a primary surface of the semiconductor region; an active layer comprising a well layer of InGaN, the active layer being provided on a primary surface of the InGaN layer; and a support base comprising a hexagonal gallium nitride and having a primary surface, the primary surface of the support base being inclined at an angle of not less than 10 degrees and not more than 80 degrees with respect to a plane perpendicular to a reference axis, and the reference axis extending in a direction of a [0001] axis of the gallium nitride, the InGaN layer being provided between the active layer and the semiconductor region, the primary surface of the semiconductor region being inclined to have semipolar nature and being inclined with respect to a plane perpendicular to an axis which extends in a direction of a [0001] axis in the primary surface thereof, the semiconductor region comprising one or more gallium nitride based semiconductor layers, each gallium nitride based semiconductor layer comprising one of GaN, AlGaN, InGaN and InAlGaN, a material of the primary surface of the semiconductor region being different from that of the InGaN layer, a thickness of the semiconductor region being larger than a thickness of the InGaN layer, the thickness of the InGaN layer being not less than 100 nm, the semiconductor region being provided on the primary surface of the support base, the InGaN layer having a first InGaN lattice constant in a first direction perpendicular to the reference axis and a second InGaN lattice constant in a second direction perpendicular to the reference axis, the first direction being perpendicular to the second direction, the support base having a first GaN lattice constant in a first direction perpendicular to the reference axis thereof and a second GaN lattice constant in a second direction perpendicular to the reference axis thereof, the first InGaN lattice constant being equal to the first GaN lattice constant, and the second InGaN lattice constant being different from the second GaN lattice constant.