Optical DLTS for the study of recombination centers in GaAsN grown by chemical beam epitaxy

Abstract

New broad DLTS peak signals in GaAsN solar cell, grown by chemical beam epitaxy, were obtained using the combination of optical-irradiation and conventional Deep Level Transient Spectroscopy (DLTS). Those broad peak signals cannot be detected by conventional DLTS method in the dark. The broad peak signals were overlapped with three deep level states at least and showed the increase of DLTS peak intensity. However, the other deep level state (EV+0.60eV) showed no significant change of DLTS peak signals in the dark and optical excitation. The condition of minority carrier injection by optical irradiation indicated that the mechanism of carrier capture and emission at some deep centers had been changed.