INCORPORATION OF NITROGEN IN ZNSE GROWN BY METALORGANIC VAPOR-PHASE EPITAXY

The incorporation processes and efficiencies of nitrogen doping for p- type conductivity in metalorganic vapour phase epitaxy (MOVPE) grown Z nSe/GaAs epilayers are investigated by means of time-integrated and ti me-resolved photoluminescence (PL) spectroscopy. Two nitrogen-doping m ethods are compared, plasma-enhanced doping during growth, and ion imp lantation of nitrogen with annealing after growth. Both types of doped layers exhibit the I1N transition from a neutral acceptor bound excit on complex (A(N)0, X), indicating an effective nitrogen embedding on s elenium sites. With increasing nitrogen doping rates, a deeper bound e xciton line I1C appears, lowering the intensity of the I1N. An observe d reduction of the I1N and I1C lifetimes for higher nitrogen doping co ncentrations results from an enhanced overlap of the bound exciton wav e functions with those of other impurity centres.