Photoluminescence Properties Of δ-Doped ZnS:Mn Grown By Metal-Organic Molecular Beam Epitaxy

Abstract

AbstractA detailed study is reported of the optical properties of homogeneously and δ-doped ZnS:Mn thin films grown by metal-organic molecular beam epitaxy. Fine structure in the Mn luminescence was observed at low Mn concentrations. The energy of the zero-phonon 4T1→6A1, transition of the Mn ion was determined to be 2.215eV, and the phonon energies associated with the transition to be 10meV and 37meV for the TA and TO phonons, respectively. It was found that the PL intensity depended on the Mn concentration and the δ-doped ZnS:Mn showed much brighter luminescence than the homogeneously doped samples with comparable Mn concentrations. For homogeneously doped ZnS:Mn with low Mn concentrations, the temperature dependence of the linewidth and the peak position was well described by the configuration coordinate model. For δ-doped ZnS:Mn, the antiferromagnetic interaction between Mn ions was invoked to explain the low temperature behavior. The luminescence lifetime measurements suggested that the δ-doping technique resulted in better incorporation of Mn ions in the ZnS host and less defect formation.