We demonstrate MOVPE-growth of InAs/AlAs0.16Sb0.84/GaSb and InAs/AlAs0.16Sb0.84/InAs heterostructures of excellent quality as observed by transmission electron microscopy and x-ray diffraction 2-theta-omega and rocking curve scans with full width at half maximum routinely below 100 ''. Key points regarding interface control for heteroepitaxial nucleation are reviewed and the choice of suitable precursors to minimize the incorporation of C and O are discussed. (c) 2013 Elsevier B.V. All rights reserved.