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 conditions has been studied. High-quality ZnS thin films, with strongly preferred orientation, can be grown under optimized conditions of substrate temperature, reactor pressure and [H2S]/[DMZn] molar ratio. The X-ray linewidth full width at half maximum (FWHM), DELTA2theta, can be reduced to below 0.175-degrees under optimized conditions. The atomic ratio of S/Zn and the lattice constant obtained are 0.96 and 5.42 angstrom, respectively. The photoluminescence (PL) and transmission spectra of the ZnS thin films have also been measured. The value of the energy gap of the ZnS thin film, which was calculated from the absorption edge, was 3.65 eV.