Study of Optical Properties of ZnIn2Se4 Thin Films by Spray Pyrolysis

Spray pyrolysis is a simple and inexpensive method to prepare thin films on large substrate area. ZnIn2Se4 thin films prepared by this method using aqueous solution of Zinc Chloride, Indium Tri-chloride and Selenium di-oxide of 0.02 M of each in the proportion 125.2 by volume. The optical band gap energy calculated from absorption coefficient was found to be decreased with increasing thickness of the films. The optical absorption studies show the existence on indirect allowed transition.