Deep-level transient spectroscopic and capacitance-voltage analyses were made of the intrinsic defects and n-type carrier concentrations that were generated by N ion implantation into n-type material. The samples were grown onto sapphire by using metalorganic vapor-phase epitaxy. The effects of implantation to various doses, and of post-implantation rapid thermal annealing, were investigated. It was observed that an increasing n-type carrier concentration and increasing defect concentration occurred with increasing N implantation dose. After rapid thermal annealing, the concentrations of free carriers and deep levels that were found in the as-grown state were regained.

D.Haase, M.Schmid, W.Kürner, A.Dörnen, V.Härle, F.Scholz, M.Burkard, H.Schweizer: Applied Physics Letters, 1996, 69[17], 2525-7