Molecular beam epitaxy of Ge–GaAs superlattices

We have fabricated Ge–GaAs superlattices on (100) GaAs over a wide range of individual layer thickness by molecular beam epitaxy. The superlattices have excellent surface finish, and high epitaxial quality in terms of low defect density and well-resolved periodicity. The effect of interdiffusion significantly affects the periodic structure only for ultrathin layers of the order of a few tens of angstroms.