Published online by Cambridge University Press: 15 February 2011
The effects of thermal annealing at 400°C in 5 MTorr of N2 on the structural and electrical properties of thin films of InN grown at 100°C on native and AIN-nucleated (00.1) sapphire by reactive magnetron sputtering have been studied. The variations in the properties of the two sets of films have qualitatively similar, yet quantitatively different dependencies on anneal time. In each case, surface decomposition to give (101) textured rods of elemental indium is seen at short anneal times, and markedly so in the more highly strained films on the AIN-nucleated substrates. The electrical properties in both cases improve with annealing time, yielding a Hall Mobility that is enhanced 2–3 times relative to as-deposited films and similar to that for films grown at a substrate temperature of 400°C. The evolution of the electrical properties appears to be relatively insensitive to the surface decomposition and to largely reflect the nature of the bulk InN Matrix.