Investigation of deep-level defects in semi-insulating GaAs and InP by analysis of photo-induced current transients

A new digital approach to PICTS technique was applied to study deep levels in undoped SI GaAs and Fe-doped InP. For SI Fe-doped InP, the 0.64-eV trap related to Fe2 + /Fe3 + acceptor level as well as the 0.53-eV trap attributed to a native defect, were observed. For SI undoped GaAs, three traps: T1 (0.58 eV), T2 (0.66 eV) and T3 (0.73 eV) assigned to the known centers EL3, HL9, and EL2, respectively, were resolved. The studies were completed by the electron spin resonance (ESR) measurements.