Patent ID: 8405066

Claim:
A nitride-based semiconductor light-emitting device comprising: a substrate of hexagonal gallium nitride-based semiconductor; an n-type gallium nitride-based semiconductor region disposed on a principal surface of the substrate; a light-emitting layer having a single-quantum-well structure disposed on the n-type gallium nitride-based semiconductor region; and a p-type gallium nitride-based semiconductor region disposed on the light-emitting layer, the light-emitting layer being disposed between the n-type gallium nitride-based semiconductor region and the p-type gallium nitride-based semiconductor region, the light-emitting layer including a well layer and a barrier layer, the well layer comprising InGaN, the principal surface extending along a reference plane tilting from a plane perpendicular to a c-axis of the hexagonal gallium nitride-based semiconductor at a tilt angle in a range of not less than 63 degrees and not more than 80 degrees or in a range of not less than 100 degrees and not more than 117 degrees, and an InGaN layer, wherein the InGaN layer is disposed between the n-type gallium nitride-based semiconductor region and the light-emitting layer, wherein a lattice constant of the InGaN layer in the direction of a first axis is larger than a lattice constant of the substrate in the direction of a second axis wherein a lattice constant of the InGaN layer in the direction of a third axis is equal to a lattice constant of the substrate in the direction of a fourth axis, wherein the first axis is shared by a first interface at the substrate side of the InGaN layer and a surface being perpendicular to the first interface and including the c-axis, wherein the second axis is shared by the principal surface and a surface being perpendicular to the principal surface and including the c-axis, wherein the third axis is perpendicular to the first axis and the c-axis, wherein the fourth axis is perpendicular to the second axis and the c-axis.