The deactivation of nitrogen accepters in ZnSxSe1-x and MgyZn1-ySxSe1-x studied by combining positron annihilation, SIMS, and CV measurements

We show that quantitative information on the electrical deactivation of dop ing can be obtained by combining the results of positron annihilation, seco ndary ion-mass spectrometry and capacitance-voltage measurements. We have a pplied this method to study the nitrogen doping in ZnSxSe1-x and MgyZn1-ySx Se1-x and we conclude that in addition to isolated acceptor impurities N-Se (-), nitrogen atoms are also situated at high concentrations in compensatin g donors, most probably in (ZniNSe)(1+) and (VSeNSe)(1+) pairs, or in elect rically neutral form, leading to electrical compensation of p-type material . (C) 1999 Elsevier Science B.V. All rights reserved.