Study of Optical energy band gap of ZnS thin films prepared at different substrate temperature

ZnS thin films are prepared on glass substrate using mixture of Zinc acetate and thiourea dissolved in double distilled water. A spray pyrolysis deposition method at different varying substrate temperature (300 0 C to 450 0 C) was carried out. The prepared ZnS thin films are characterized by optical absorption using UV – Visible Spectrophotometer. X ray diffractrometer recording was carried out using Cuα target. Thin film materials show strong absorption at 410 nm region. The absorption edge is used to calculate the optical energy band gap. The calculated values of energy band gap of ZnS films at different temperature are found to be with little variation. The plots of absorption coefficients vs photon energy at strong absorption edge are helpful to decide the nature of deposited films on glass substrate.