Gallium nitride (GaN), grown by HVPE, was implanted with 300 keV Eu ions and then
annealed at 1000 oC . Deep level transient spectroscopy (DLTS) and Laplace DLTS (L-DLTS) were
used to characterise the ion implantation induced defects in GaN. Two of the implantation induced
defects, E1 and E2, with DLTS peaks in the 100 – 200 K temperature range, had DLTS signals that
could be studied with L-DLTS. We show that these two defects, with energy levels of 0.18 eV and
0.27 eV below the conduction band, respectively, are two configurations of a metastable defect.
These two defect states can be reproducibly removed and re-introduced by changing the pulse, bias
and temperature conditions, and the transformation processes follow first order kinetics.