Samples of p-type N-doped ZnSe were grown onto n+-type GaAs by means of molecular beam epitaxy, and were studied by using deep-level transient spectroscopy and double correlation deep-level transient spectroscopy. In order to produce p-type doping of ZnSe, an active N beam which was produced by a free-radical plasma source was used. Four hole traps, with activation energies of 0.22, 0.51, 0.63, and 0.70eV, were detected by means of deep-level transient spectroscopy. Two of these, at 0.51 and 0.63eV, had never been observed before in ZnSe. It was suggested that they were probably introduced by N doping. The properties of the other 2 traps, at 0.22 and 0.70eV, supported the hypothesis that both of them were associated with native defects. It was thought that this was the first direct experimental investigation of deep states in p-type ZnSe.

B.Hu, G.Karczewski, H.Luo, N.Samarth, J.K.Furdyna: Applied Physics Letters, 1993, 63[3], 358-60