Thin-film solar cells are a new type of photovoltaic device to alleviate the energy crisis. Thin-film solar cells can be manufactured using low-cost ceramics, graphite, metal sheets and other materials as substrates. The thickness of the thin film that can generate voltage is only a few μm, and the current conversion efficiency can reach up to 18%. In addition to the plane, the thin-film solar cell can be made into a non-planar structure because of its flexibility. It has a wide range of applications. It can be combined with a building or become a part of a building, and it has a wide range of applications. The main categories are CdTe, CIGS, GaAS, polysilicon film and other types.