Concentration of interstitial and substitutional nitrogen in GaNxAs1−x

The interstitial to substitutional nitrogen atoms as a function of concentration in GaNAs were determined by nuclear reaction analysis utilizing the N14(d,p) N15 and N14(d,α) C12 reactions using ion channeling technique. The GaNAs films with mean nitrogen concentration between 0.3% and 3%, measured with secondary ion mass spectrometry and time-of-flight elastic recoil detection analysis, were grown using gas-source molecular-beam epitaxy. The fraction of nitrogen atoms occupying substitutional sites was observed to increase linearly with increasing nitrogen amount, while the concentration of interstitial nitrogen was nearly constant at 2×1019 cm−3 throughout the concentration region. Annealing at 750 °C decreases the concentration of interstitial nitrogen.