Ion beam and photoluminescence studies of Er and O implanted GaN

The annealing behavior and the lattice site location of Er and Er+O (only E r was localized) implanted into GaN single crystalline epilayers were studi ed with the RBS/channeling and photoluminescence techniques. After implanta tion the results show that for doses of 6x10(14) Er+/cm(2) the Er ions occu py substitutional sites in the GaN lattice as revealed by detailed angular scans along the [1 0 (1) over bar 1] and [0 0 0 1] axes. An increase of the dose to 6x10(15) Er+/cm(2) produces a continuous amorphous layer. The dama ge produced by the implantation starts to anneal at 600 degrees C, For the samples implanted with the lower dose the recovery is significant after 2 m in annealing at 900 degrees C. During the annealing process Er remains in s ubstitutional sites. The presence of O seems to slightly increase the subst itutional fraction after annealing at 900 degrees C, Further the photolumin escence signal is more intense for the sample co-doped with oxygen. (C) 199 9 Elsevier Science B.V. All rights reserved.