Lattice location of Si in ion implanted GaN

The lattice location of Si in GaN has been investigated by ion channeling in combination with Rutherford backscattering spectrometry, particle induced x-ray emission, and nuclear reaction analysis. Metalorganic chemical vapor deposition grown GaN on c-plane sapphire substrates and implanted with Si28 at a dose of 7×1014 cm−2 with postimplant annealing were investigated. It was found that almost 100% of Si goes into the Ga site at 1100 °C. Our results directly indicate that the electrical activation of Si implanted GaN with postimplant annealing is due to the formation of substitutional Si at this temperature.