A study was made of Ni/n-GaN Schottky contacts, implanted with 25keV protons. The defects thus introduced were studied by using deep level transient spectroscopy. It was found that 25keV proton implantation introduced a complex set of electron traps into GaN; most of which were different to the defects which were observed after high-energy (MeV) electron or proton implantation. Two prominent defects, which could be clearly distinguished from each other, had energy levels at 0.22 and 0.30eV below the conduction band. At least 3 of the defects which were detected after 25keV proton implantation exhibited a metastable nature, in that they could be reproducibly removed and re-introduced during reverse- and zero-bias annealing cycles.

Electron Traps Created in n-Type GaN during 25keV Hydrogen Implantation. F.D.Auret, W.E.Meyer, S.A.Goodman, M.Hayes, M.J.Legodi, B.Beaumont, P.Gibart: Materials Science and Engineering B, 2002, 93[1-3], 6-9