Donor-acceptor pair luminescence decay in Mg-doped GaN

The photoluminescence decay measurements of donor-acceptor pairs (DAP) reco mbination in Mg-doped GaN grown by MOCVD are presented. The DAP luminescenc e decays with several hole concentrations (<1x10(17) cm(-3) to similar to 4 x10(17) cm(-3)) were observed. The decay time of the DAP transition in the annealed sample is faster than in as-grown. It is considered as due to the increase of nonradiative process by the enhancement of the interactions amo ng DA pairs. This shows another aspect of the activation of Mg accepters af ter thermal annealing. The characteristics of DAP recombination dynamics in Mg-doped GaN are also described.