Epitaxial In.sub.x Ga.sub.(1-x) As having a slanted crystallographic plane azimuth

摘要

A semiconductor epitaxial substrate, characterized in that a crystal is formed by epitaxial growth on a gallium arsenide single crystal substrate whose crystallographic plane azimuth is slanted from that of one of {100} planes at an angle of not more than 1, that at least part of the epitaxial crystal is an In.sub.x Ga.sub.(1-x) As crystal (wherein 0 x 1), and that the epitaxial growth is carried out by chemical vapor deposition. Since the In.sub.x Ga.sub.(1-x) As layer has reduced microscopic unevenness and reduced variation in thickness, the epitaxial substrate of the present invention can be used as a channel layer of a field effect transistor or as an active layer of a semiconductor laser to endow these devices with excellent characteristics.