Identification of implantation-induced defects in GaN: A near-edge x-ray absorption fine structure study

Abstract

We apply near-edge x-ray absorption fine structure spectroscopy, at the N K edge, in order to identify the signature of implantation-induced defects in the partial density of empty states in GaN implanted with O, Mg, and Si ions. The dose range was 1014–1018 cm−2. It is found that two of the implantation-induced defects introduce characteristic resonances (hereafter called RL1 and RL2) in the near-edge x-ray absorption fine structure spectra. RL1 appears 1.7 eV below the absorption edge, its formation is independent of the projectile and the implantation dose, and is attributed to nitrogen interstitials. RL2, which appears at about 1.0 eV above the absorption edge, is generated when the dose exceeds 1016 cm−2 and is attributed to nitrogen dangling bonds.