Preparation Of Large Scale CdS Thin Films By CBD For Solar Cells

Cd S thin film is widely used in solar cell.It is used as buffer layer in CIGS and CZTS solar cells. Cd S is used as an n-type semiconductor in Cd Te solar cell,as well as it is used in CIGS solar cell as buffer layer,the function is to modify band gap gradient between the CIGS and Zn O.In order to prepare proper Cd S thin film with high transmittance and high resistance,some processes has been used, like chemical vapor deposition,electroplating,ratio frequency magnetron sputtering and chemical bath deposition.Otherwise CBD method is usually used in preparing Cd S buffer layer,and the CBD method is cheap and could prepared Cd S thin film with less lattice mismatch. In the process of the CBD it could be classified by the quantity use of ammonia,there is high ammonia method and less ammonia method and no-ammonia method.We modified process to prepare lager scale Cd S thin films(10×10cm) in order to reduce the resource and accelerate deposition rate.And the Cd S thin film with high transmittance and good uniformity will be used in solar cell.It contains two processes,that is ion by ion heterogeneous reaction and cluster by cluster homogeneous reaction,and the heterogeneous reaction is desirable in preparing Cd S thin films with high transmittance and it could adhere with CIGS well.We modified the rate of the agitator and the ratio of each medicine to adapt this situation, the Cd S thin film with high transmittance and good uniformity will be used in solar cell.