A STUDY OF DEEP-LEVEL DEFECTS IN METALORGANIC VAPOR-PHASE-EPITAXY-GROWN ZNSE ON GAAS BY DEEP-LEVEL TRANSIENT SPECTROSCOPY

Deep-level defects in Li+-implanted ZnSe epilayer grown by metalorganic vapor-phase epitaxy (MOVPE) on a GaAs substrate have been characterized by using the deep-level transient spectroscopy method under different post-implantation annealing conditions. Four electron traps with energy levels of Ec-0.3, 0.33, 0.55, and 1.02 eV and one hole trap with an energy level of Ev+0.23 eV were detected. Possible physical origins and formation mechanisms for these defects were discussed using the defect model proposed by Myles and Sankey [Phys. Rev. B 29, 6810 (1984)]. The results showed that interdiffusion between the ZnSe/GaAs heterointerface plays an important role on the formation of native defects in the MOVPE-grown ZnSe epitaxial films on the GaAs substrate.