Babatunde Rasaq Ayinla & Odunaike Rasaki Kola

Solar cells fabricated from silicon are very expensive because of the high cost of production of silicon waivers. Thin film solar cells require a thin absorbing layer. CdTe and CIGS contained toxic and rare elements which have limitations in their usages. CZTS thin films were deposited as absorber layers of thin film solar cells by the CBD technique. The sources of Cu, Zn, Sn and S were Copper nitrate, zinc nitrate, tin chloride and thiourea, respectively. The copper concentrations varied between 0.2 M and 0.5 M while the concentration of every other constituent of the film was constant. The concentration effect of copper was studied on optical parameters such as absorbance, transmittance, reflectance and band gap energy. The analysis revealed that the films had high absorbance, low reflectance and transmittance between 400 and 700 nm of electromagnetic radiation. The bandgap energy was between 1.56 and 1.62 eV Keywords: Thin films, CZTS, transmittance, bandgap 0150