Ge-GaAs superlattices by molecular beam epitaxy

We have grown Ge-GaAs superlattices on (100) GaAs by molecular beam epitaxy at ∼400°C, with individual layer thicknesses ranging from 25 to 1000 Å. Good surface finish and crystalline quality are obtained, except in the lower thickness limit. For configurations where the effect of interdiffusion is shown to be negligible, well-defined periodicity is observed from both x-ray diffraction measurement and Rutherford backscattering spectrometry.