NITROGEN DOPANT SITE WITHIN THE ZNSE LATTICE AS STUDIED BY ION-BEAM ANALYSIS

The N dopant site within the ZnSe lattice was investigated using the c hanneling technique in combination with nuclear reaction analysis (cha nneling-NRA). We used the nuclear reaction N-15 (p,alpha) C-12 for non -destructive N detection and improved the detection limit of N up to 1 x 10(17) cm(-3). Molecular beam epitaxy (MBE) grown ZnSe doped with N -15 as high as 2-6 x 10(18) cm(-3) was the subject of investigation. W e found that a large fraction of N is distributed randomly and that so me N are in tetrahedral interstitial sites. Our analysis established t hat the fraction ofN distributed randomly and the fraction in the tetr ahedral sites are increased and the fraction in the substitutional sit es is decreased as the activation ratio ((N-a-N-d)/[N]) decreases. We think that the randomly distributed N are likely to be neutral N-N com plex defects such as N in Se sites combining with N in Zn sites (N-Se- N-Zn) and that N in the tetrahedral sites (N-tet) might form N-Se-N-te t complex defects that neutralize the N-Se acceptor activity. (C) 1998 Elsevier Science B.V. All rights reserved.