SOS Substrate for semiconductor device

摘要

The invention provides an SOS substrate for a semiconductor device wherein an epitaxial silicon layer which has an index of plane (100) is formed on a single crystal sapphire plate which has an index of plane (1012). An orientation flat is formed at an incline angle of 2.1 to 2.2 DEG with respect to a [011] or [011] direction on the surface of the epitaxial silicon layer which has the index of plane (100). The direction of the orientation flat on the surface of the sapphire plate is aligned with the direction of a cleavage plane of the sapphire plate.