Chemical bath deposition of Cadmiumbarium sulphide (CdBaS) thin film and its thickness effect on bandgapenergy

Abstract

This study was basicallycentred on the chemical bath deposition technique of CdBaS (Cadmium Barium sulphide), and to determine the effect of thin film thickness on the bandgap energy of chemically deposited CdBaS. The thin films of CdBaS were deposited on several samples of glass slides using a chemical bath deposition (CBD) technique. Several precursors were used suchas CadmiumSulphate (CdSO₄ Ammonia (NH₃), Thiourea (T.U) CH₄N₂S and Barium Sulphate (BaSO₄).The deposition of CdBaS depends on the parameters such as volume of precursors, deposition temperature and dip time to uncover the properties of the thin film using spectrophotometer. Annealing of substrate involves heating of films at high temperatures. Annealing was done at 100⁰C, 200⁰C, 300⁰C, 400⁰C and 500⁰C. The concentrations of NH₃ and BaSO₄ were varied in different sample of beakers. The result shows that the bandgap energy increases as temperature and film thickness increases.