OPTICAL CHARACTERIZATION OF HIGHLY MISMATCHED INP GAAS(111)B EPITAXIAL HETEROSTRUCTURES/

In this work, we investigate heteroepitaxial layers of InP with variou s thicknesses grown by metalorganic chemical Vapor deposition on (111) B surfaces of GaAs substrates. We evaluate the heteroepilayers using l ow temperature photoluminescence (PL) and we discuss the dependence of the PL spectrum on temperature for the thick epilayer. We determine t he residual strain for the various layer thicknesses with photolumines cence excitation spectroscopy. The strain is due to different lattice constants of layer and substrate material and is relaxed by the nuclea tion of misfit dislocations during growth. This relaxation process dep ends on substrate orientation, layer thickness and growth conditions. (C) 1997 Elsevier Science Ltd.