Silicon/Germanium Strained-Layer Superlattices

Abstract

High quality Si/Ge strained layer superlattices are achieved by low temperature molecular beam epitaxy on Si, SixGe1−x and Ge substrates. Various characterization techniques are used to obtain information on critical thickness, strain distribution, misfit dislocations, interface sharpness and superlattice periodicity. The band structure is strongly influenced by strain and zone folding effects. Two-dimensional electron systems can be realized in the wider gap Si layers due to the strain-induced lowering of the conduction band. New optical transitions in the infrared regime are observed with short period Si/Ge superlattices.