Molecular beam epitaxial growth of high quality HgTe and Hg 1-xCdxTe onto GaAs(001) substrates

Abstract

HgTe and Hg1-xCdxTe epilayers have been grown for the first time onto GaAs (001) substrates by molecular beam epitaxy (MBE). A thin MBE CdTe buffer has been first deposited. The (001) orientation of the substrate is conserved during the growth. Despite the important lattice mismatch in situ electron diffraction experiments showed that the films have a high crystal quality. Hall measurements carried out on these layers confirm their high quality because they exhibited high electron Hall mobilities. We have shown also, using a Hall mobility profiling etching technique, that the interfacial disorder zone in a HgCdTe layer deposited on a 0.4-μm CdTe buffer layer could be less than 1 μm. This first report of very good electrical performances for Hg1-xCdxTe layers grown onto GaAs substrates is highly promising for growth and device applications regarding this material and related superlattices.