Growth and characterization of spray-deposited Cu₂ZnSnS₄ thin films by using two different carrier gases

Cu2ZnSnS4 is a promising renewable energy thin film semiconducting material used in heterojunction solar cells. These films have been deposited at the optimized condition of the spray pyrolytic technique. Compressed air and nitrogen are used as carrier gases for the deposition of the films. The X-ray diffraction studies and micro-Raman analysis confirm the structure of these films as kesterite. The crystallinity of the films depends on the nature of the carrier gas. The microstrain and dislocation density in the films is found to decline when the films deposited with nitrogen are used as carrier gas. The optical studies confirm these materials exhibit a direct band gap and are close to 1.53 eV. The material shows p-type conductivity. A heterojunction Cu2ZnSnS4 thin film solar cell is fabricated using simple chemical methods and this cell shows a maximum efficiency of about 0.8%.