Low-pressure metalorganic vapour phase epitaxy growth of InAs/GaAs short period superlattices on InP substrates

Abstract

Short-period strained-layer superlattices (SPSLSs) could potentially find applications as replacements for the corresponding alloys combining superlattice effects with those associated to strain. For more fundamental research, SPSLS have attracted considerable interest due to their capability of exhibiting the physical behaviour of binary in horizontal and of ternary alloy in vertical direction. The characterization of interface qualities in dependence of growth parameters like growth temperature and layer growth time is of particular interest in such highly strained heterostructure systems. In this work we will show the capability of low-pressure metalorganic vapour phase epitaxy (LP-MOVPE) growth for InAs/GaAs ultra-short period superlattices on InP substrates. A detailed study of growth characteristics of highly strained extremely thin InAs and GaAs layers on InP substrates was made. Single strained layer heterostructures as well as SPSLS were grown. InAs/In 0.53Ga 0.47As, GaAs/In 0.53Ga 0.47As and InAs/GaAs/In 0.53Ga 0.47As superlattice structures were grown with respect to the special requirements of high resolution X-ray diffraction (HRXRD). Experimental rocking curves were compared with computer aided simulations which confirmed our method for individual layer thickness evaluation on the base of experimental data solely.