Layers which were doped with P and I were grown onto (001)GaAs substrates by means of atmospheric-pressure metalorganic vapor-phase epitaxy. Temperature-dependent near-bandgap photoluminescence measurements permitted the ground state of P acceptors (0.062eV) to be determined. Resonant excitation methods such as selective-pair luminescence and 2-hole transitions permitted the investigation of excited acceptor states in epitactically grown layers. It was found that I-doped ZnTe layers exhibited strong emission bands at 2.24 and 2.22eV. Their intensities depended upon the partial pressure ratio of the I organyl to the Te organyl during growth. The first emission band was attributed to the incorporation of impurity atoms with a binding energy of about 0.145eV. This value was in good agreement with the binding energy of Cu in ZnTe. The emission band at 2.22eV was attributed to Zn-vacancy plus I complexes (VZn-I). A binding energy of 0.17eV for these luminescence centers was deduced from temperature-dependent measurements.

K.Wolf, M.Wörz, H.P.Wagner, W.Kuhn, A.Naumov, W.Gebhardt: Journal of Crystal Growth, 1993, 126[4], 643-50