Patent ID: 8111350

Claim:
A semiconductor light-emitting device, comprising: a substrate having a corundum crystal structure that has a c-axis facing in a thickness direction, a plurality of protrusions being formed on a surface of the substrate; a base film formed on the surface of the substrate, on which the plurality of protrusions are formed, the base film being made of a III-V compound semiconductor including Ga and N, a surface of the base film being flatter than the surface of the substrate; and a light emitting structure, formed on the base film, that includes an n-type semiconductor layer and a p-type semiconductor layer, which are made of III-V compound semiconductors including Ga and N; wherein when a direction that is tilted by less than 15 degrees with respect to an a-axis of the base film is designated as a first direction and another direction orthogonal to the first direction is designated as a second direction, the protrusions are regularly arranged, in the first direction and the second direction, a planar shape of each protrusion having edges matching the four sides of a quadrangle, the quadrangle having a pair of first sides tiled by less than 15 degrees with respect to an m-axis of the base film and a pair of second sides tilted by less than 15 degrees with respect to the a-axis of the base film, the first sides, which face each other, of quadrangles matching two adjacent protrusions in the first direction are mutually parallel, and the second sides, which face each other, of the quadrangles corresponding to two adjacent protrusions in the second direction are mutually parallel, an interval between the two second sides, which face each other, in the m-axis direction being wider than an interval between the two first sides, which face each other, in the a-axis direction.