AN OPTICAL METHOD FOR EVALUATION OF THE NET ACCEPTOR CONCENTRATION INP-TYPE ZNSE

We report photoluminescence (PL) results obtained on p-type ZnSe epila yers grown by molecular beam epitaxy. As an acceptor dopant, we used a n active nitrogen beam produced by a free radical nitrogen source. On the basis of a detailed analysis of PL data we propose a simple semiqu antitative method for a quick and contactless evaluation of the net ac ceptor concentration in p-type ZnSe. In particular, we show that the i ntensity ratio of the donor-acceptor pair (DAP) emission to the accept or-bound exciton (I1) emission strongly depends on both the excitation power and the quality of the sample, and because of that it cannot by itself be regarded as a good measure of the net acceptor concentratio n. On the other hand, the intensity of the DAP emission under saturati on excitation shows a simple direct proportionality to the net accepto r concentration, thus providing a reliable tool for determining the re lative doping level in p-type ZnSe films.