The Influence of Cycle Sputtering Deposition on the Properties of Cu₂ZnSnS₄ Thin Films

Three kinds of precursor thin films with stacking orders of Cu/Sn/ZnS, Cu/Sn/ZnS/Cu/Sn/ZnS and Cu/Sn/ZnS/Cu/Sn/ZnS/Cu/Sn/ZnS were prepared by magnetron sputtering and annealed with sulfur powder. The microstructure, morphology and optical properties of thin films were investigated by X-ray diffraction, the Raman scattering, scanning electron microscopy and UV-visible spectrophotometer. The increase of cycle number decreases the sulfurizing temperature of the formation of Cu₂ZnSnS₄ phase. Chemical composition can be controlled by cycle sputtering deposition. After sulfurizing at 500°C, the particle size and the band gap increase with increasing cycle number.