Synthesis of CZTS solar cell absorber material by chemical spray pyrolysis method

Abstract

Thin films of Cu₂ZnSnS₄ (CZTS) is one of the most promising semiconductor materials for absorption layer in thin film solar cells because of its suitable optical band gap, cost-effective and eco-friendly nature. CZTS thin films were successfully deposited on soda lime glass substrates using spray pyrolysis and the effect of variation of substrate temperature on the structural and optoelectronic properties was investigated. The depositions were carried out on substrate temperature at 400⁰C. The structural, optical, morphological and elemental  composition of the deposited films were characterized by X- ray diffraction (XRD),  UV-visible spectroscopy, Field Emission Scanning Electron Microscope (FESEM) and Energy Dispersive analysis of X-ray(EDAX). The powder X-Ray diffraction of the deposited thin films showed that the crystallinity was improved with increasing substrate temperature and it has a polycrystalline nature with (112), (220) and (312)  phases. Optical band gap of the films had been studied using UV–Vis spectrometer and was found to be 1.95 eV which is close to the ideal band gap for highest theoretical conversion efficiency of solar cell