This article examines the feasibility of fabricating polycrystalline ZnS and ZnS:Mn films with a size of 9 in. diagonal (190 mm x 130 mm) for use in thin film electroluminescent display via low pressure metallorganic chemical vapor deposition. The uniformities of film thickness and crystallinity are studied as functions of H-2 flow rate, the slit width of inlet nozzles, and the manganese concentration. Uniform polycrystalline ZnS and ZnS:Mn films are also obtained. Film thickness Variance is controlled below +/-3%. Less than +/-5% variation in x-ray full width at half maximum is obtained in the ZnS film as well. The atomic ratio of S/Zn is close to unity value, as estimated by the measurement of electron probe microanalyzer. In addition, the distribution of manganese dopant concentration in ZnS:Mn films is also uniform. The uniform counts of Zn, S, and Mn atoms persist throughout the ZnS:Mn films, as demonstrated by the secondary ion mass spectrometry. Moreover, atomic force microscopy image root-mean-square roughness of film’s surface is measured to be 93 Angstrom.