Copper zinc tin sulfide thin film solar cell device and preparation method thereof

Provided is a copper zinc tin sulfide thin film solar cell device based on a polyimide flexible substrate. 1) The polyimide flexible substrate thin film solar cell has high weight ratio power, has the advantages of flexibility, foldability and bumping and dropping resistance; the cost reduction potential is big, and the method is suitable for large-scale roll-to-roll process; and 2) copper zinc tin sulfide components are rich in reserves and are pollution-free to environment; the preparation cost is low; the forbidden band width is about 1.45eV, very close to the ideal band gap 1.4eV of a photovoltaic cell; the copper zinc tin sulfide is a direct band gap p-type semiconductor material, optical absorption coefficient being more than 10 cm, and is very suitable for serving as the absorbing layer material of the thin film solar cell; and the cell conversion efficiency is high, and conversion efficiency can reaches the highest conversion efficiency of a single junction cell theoretically. The advantages are that the cell preparation method is simple, is easy to carry out, is beneficial for large-scale popularization and application, and has vitally important application prospect in space and special occasions.