Synthesis and structural characterizations of Cu2ZnSnS4 thin films

We investigate the synthesis of kesterite Cu₂ZnSnS₄ (CZTS) thin films using thermal evaporation from copper, zinc and tin pellets and post-annealing in sulfur atmosphere at 600 ^°C. X-ray diffraction and Raman scattering results show that the films produced from a Cu/Sn/Cu/Zn precursor at 600^°C for 4 hours are kesterite phase CZTS with traces of ZnS. Grain sizes of 1 um or above are obtained from SEM images. We explored the effect of the sulfurization temperature, sulfurization time and metal precursor evaporation sequence on the CZTS structure and film morphology. The beneficial effect of impurity diffusion in grain growth has also been observed in this work.