An almost 100&percent; activation ratio{(NA-ND)/[N]}for a nitrogen-doped ZnSe molecular beam epitaxy (MBE) layer with the highest net acceptor concentration(NA-ND)of1.2×1018 cm−3was obtained using a high-power rf plasma source. Even at this highNA-NDvalue, a 4.2 K photoluminescence spectrum shows bound exciton emission and deep donor–acceptor pair emission with well-resolved phonon replicas. The high activation in nitrogen doping could be ascribed to the generation of the predominant atomic nitrogen and to the suppressed extraction of nitrogen ions and excited neutral nitrogen molecules due to the structure of the orifice placed between the MBE growth chamber and the plasma discharge tube of the high-power plasma source. ©1997 American Institute of Physics.