Mg implantation in AlN layers on sapphire substrates

Abstract

Mg ions were implanted in 1 μm thick AlN layers grown on sapphire substrates. The Mg implantation with a total dose of 5 × 1014 cm−2 introduced Al-vacancy related defects, which were decreased by annealing at temperatures over 1400 °C in an N2 ambient. We found that annealing temperatures over 1400 °C were necessary for an electrically conductive Mg-implanted AlN layer. The Mg-implanted AlN layer annealed at 1500 °C showed 1.1 nA at a bias of 100 V at room temperature and 7 nA at a bias of 10 V at 300 °C.