INFLUENCE OF SUBSTRATE DOPANT TYPE ON THE OPTICAL-PROPERTIES OF GAINAS INP MULTIQUANTUM-WELL STRUCTURES GROWN BY LOW-PRESSURE MOVPE/

A correlation between substrate dopant type and the absorption spectra of MQW structures has been identified. Optical absorption spectra fro m MQW structures grown on S-doped InP can show poorly resolved exciton ic features with respect to those obtained from structures grown on bo th Sn- and Fe-doped substrates. It is proposed that this degradation i s due to enhanced interfacial diffusion on the Group V sublattice for structures grown on substrates incorporating low defect densities.