Photoresponse of the AsGa antisite defect in as-grown GaAs

Abstract

The photoresponse of the As+Ga antisite electron-paramagnetic-resonance (EPR) has been studied in as-grown semi-insulating GaAs as a function of illumination time and photon energy hν. The As+Ga EPR signal intensity changes are nonmonotonic in time in the range 1.1≲hν≲1.4 eV. The spectral dependences of As+Ga enhancement and quenching show distinct similarities with the EL2 optical cross sections σ0n (hν) and σ0p (hν), respectively. These results demonstrate that the EL2 defect and the AsGa antisite have practically identical optical and photoelectronic properties.