LOW-TEMPERATURE PHOTOLUMINESCENCE STUDY ON ER-DOPED GAP GROWN BY ORGANOMETALLIC VAPOR-PHASE EPITAXY

Low-temperature photoluminescence spectra of Er-doped GaP grown by low -pressure organometallic vapor phase epitaxy was investigated under bo th above-band gap and below-band gap excitation conditions. Under all experimental conditions, similar Er-related spectra dominated by numer ous sharp emission Lines were obtained for the first time. The intensi ty dependence of the photoluminescence exhibits complicated behavior a nd is modeled using a unique energy-transfer process. The results obta ined indicate that some Er-related luminescence centers are efficientl y activated by direct excitation of electrons to some traps related to the luminescence centers. (C) 1998 American Institute of Physics.