First-principles pseudopotential calculations were used to study N-doping levels. The formation energy of a N acceptor was found to be lower by about 0.13eV, and the hole carrier density higher by about 5 times, as compared with ZnSe. At doping levels above 1019/cm3, the doping efficiency fell rapidly. This was due to neutralization by inert N2 molecules, or to compensation by split-interstitial N-N complexes; depending upon the stoichiometry.

B.H.Cheong, K.J.Chang: Materials Science Forum, 1995, 196-201, 303-8