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 Si-28 at a dose of 7 x 10(14) cm(-2) with postimplant annealing were investigated. It was found that almost 100% of Si goes into the Ga site at 1100 degrees 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. (C) 1998 American Institute of Physics. [S0003-6951(98)04836-0].