Photoluminescence Imaging of III-V Substrates and Epitaxial Heterostructures

Abstract

AbstractThe characterization of III-V compound semiconductor substrates and epitaxial layers with photoluminescence imaging is reviewed. The luminescence patterns of semi-insulating GaAs are dominantly determined by the concentration and distribution of nonradiative recombination centers, as shown by comparison with spectroscopic temperature and lifetime topography of photoexcited carriers. Wafers fabricated with various growth and annealing procedures are evaluated. Presently available informations on nonradiative centers in GaAs are summarized and discussed. The correlation of luminescence, absorption and resistivity topograms of InP substrates shows various interrelated influences of the Fe acceptor distribution. High resolution luminescence images of growth induced, strain induced and substrate induced defects in epitaxial heterostructures are obtained. The generation of relaxation dislocations in pseudomorphic layers is influenced by growth parameters, layer structures, layer doping and also by substrate properties. Nonradiative recombination center patterns replicate the arrangement of threading dislocations in the substrate.