Thermal decomposition of zinc 2-ethyl-hexanoate solution on glass substrates gave zinc oxide thin films. Zinc sulfide thin films were obtained by sulfidation of the zinc oxide films in a hydrogen sulfide atmosphere. The ZnS films were transparent, had a high degree of crystallinity with {111} preferred orientation, and the breakdown voltage of these films was about 28Vrms at a film thickness of 430nm (breakdown field was about 0.65MV/cm). The microstructure of the cross section of the ZnS thin films formed on a glass substrate was a particle-stacked structure, which is different from the columnar or conical grain structures obtainable by electron beam evaporation or sputtering. MIS (Metal/Insulator/Semiconductor)-type and sandwich (Metal/Insulator/Semiconductor/Insulator)-type thin film EL (electroluminescent) devices fabricated using the ZnS thin films showed EL emission above 100 ft-L at 130Vrms, 5kHz sine wave.