DEEP HOLE TRAPS IN P-TYPE NITROGEN-DOPED ZNSE GROWN BY MOLECULAR-BEAMEPITAXY

P-type nitrogen,doped ZnSe grown on n+ -GaAs by molecular beam epitaxy has been studied by deep-level transient spectroscopy (DLTS) and doub le correlation DLTS. To achieve p-type doping of ZnSe, we employed an active nitrogen beam produced by a free-radical plasma source. Four ho le traps-with activation energies of 0.22, 0.51, 0.63, and 0.70 eV-wer e detected by DLTS. Two of these-those at 0.51 and 0.63 eV-have never been observed before in ZnSe. They are probably introduced to the mate rial by nitrogen doping. The properties of the other two traps-at 0.22 and 0.70 eV-support the hypothesis that both of them are associated w ith native defects, in agreement with earlier reports. To our knowledg e this is the first report about direct experimental investigation of deep states in p-type ZnSe.