THE PREPARATION OF ZNS THIN-FILMS ON AN INDIUM TIN OXIDE GLASS SUBSTRATE BY LOW-PRESSURE METALORGANIC CHEMICAL-VAPOR-DEPOSITION

The dependence of the crystalline quality of ZnS thin films, deposited on an indium tin oxide/glass (ITO/glass) substrate by a low-pressure metalorganic chemical vapor deposition (MOCVD) system, on deposition c onditions has been studied. High-quality ZnS thin films, with strongly preferred orientation, can be grown under optimized conditions of sub strate temperature, reactor pressure and [H2S]/[DMZn] molar ratio. The X-ray linewidth full width at half maximum (FWHM), DELTA2theta, can b e reduced to below 0.175-degrees under optimized conditions. The atomi c ratio of S/Zn and the lattice constant obtained are 0.96 and 5.42 an gstrom, respectively. The photoluminescence (PL) and transmission spec tra of the ZnS thin films have also been measured. The value of the en ergy gap of the ZnS thin film, which was calculated from the absorptio n edge, was 3.65 eV.