Metallorganic chemical vapor deposition of InAs/GaSb superlattices on GaAs substrates using a two-step InAs buffer layer

Abstract

InAs/GaSb type II superlattices (T2SLs) were grown heteroepitaxially, via metallorganic chemical vapor deposition (MOCVD), on GaAs substrates. The 7% lattice mismatch between the T2SL and GaAs substrate was accommodated through the use of a two-step InAs buffer layer. The periodicity of the grown structures was confirmed by X-ray diffraction (XRD). FTIR measurements of the structures yielded cutoff wavelength values from 4.9 mu m to 8.7 mu m, which, as expected, scaled with thickness of the InAs in the SL structure. Kronig-Penny modeling of the structures produced the general trend of the experimental data. (C) 2011 Elsevier B.V. All rights reserved