Lattice location of chromium in semi-insulating GaAs by ion channeling techniques

Abstract

Proton-induced x-ray emission combined with ion channeling techniques has been used to investigate the lattice location of Cr in GaAs grown by the Czochralski method. The angular dependence of Cr x-ray yields about the 〈100〉 and 〈110〉 directions indicated that the Cr atoms occupied the substitutional sites with no trace of well-defined Cr interstitials at the concentrations studied. Fe and Ni impurities in Cr-doped GaAs were located at the substitutional sites whereas Cu impurities were more likely distributed among random sites with respect to the host atoms.