Single-crystal Sn/Ge superlattices on Ge substrates: Growth and structural properties

Abstract
Short‐period strained‐layer α‐Sn/Ge superlattices lattice matched to Ge(001) substrates have been synthesized for the first time. The thin, tetragonally distorted α‐Sn layers are stabilized by a modified molecular beam epitaxy technique with large modulation of substrate temperature during growth. Optimization of growth conditions is achieved via in situ Auger electron spectroscopy and low‐energy electron diffraction. This new kind of strained‐layer superlattice is characterized by transmission electron microscopy, x‐ray diffraction, and Raman scattering. Distinct superlattice effects are observed in the structural and phonon properties of the samples.