Gallium nitride-based semiconductor optical device, method of fabricating gallium nitride-based semiconductor optical device, and epitaxial wafer

Abstract

A gallium nitride-based semiconductor optical device is provided that includes an indium-containing gallium nitride-based semiconductor layer that exhibit low piezoelectric effect and high crystal quality. The gallium nitride-based semiconductor optical deviceincludes a GaN support base, a GaN-based semiconductor region, and well layers. A primary surfacetilts from a surface orthogonal to a reference axis that extends in a direction from one crystal axis of the m-axis and the a-axis of GaN toward the other crystal axis. The tilt angle Ais 0.05 degree or more to less than 15 degrees. The angle Ais equal to the angle defined by a vector VM and a vector VN. The inclination of the primary surface is shown by a typical m-plane Sand m-axis vector VM. The GaN-based semiconductor regionis provided on the primary surface. In the well layersin an active layer, both the m-plane and the a-plane of the well layerstilt from a normal axis Aof the primary surface. The indium content of the well layersis 0.1 or more.