High temperature growth of ZnS films on bare Si and transformation of ZnS to ZnO by thermal oxidation

ZnS films were grown on Si (100) at high temperatures by pulsed laser deposition using a KrF excimer laser. The growth temperature was varied from 200 to 700 °C and all films were found to have a specific preferential orientation. With increasing $T_s,$ growth rate decreased but the quality of the film improved. The highest quality ZnS film was obtained at 700 °C. The presence of ${\mathrm{ZnS}}^{+}$ ions among the ablation products of a ZnS target was verified by laser desorption time of flight mass spectroscopy measurements. ZnO was formed by thermal oxidation of ZnS and the films showed strong near band-edge emission at 3.26 eV.