A one-dimensional modeling tool for solar cells called SCAPS on CZTS/ZnS

Abstract

In the study, Zinc sulphide thin films were deposited related to different annealing ambient by ultrasonic spray pyrolysis technique (USP) on soda lime glass substrates. Optical properties of these films were analyzed by using ultraviolet–visible (UV–Vis) spectrophotometry at room temperature. Ultraviolet– visible spectroscopy measurements indicate that all ZnS thin films indicated high extinction coefficient in the NIR region. ZnS thin films, which was un annealed and annealed at N2 atmosphere show higher skin depth in the low and high energy bands. However, the skin depth of ZnS thin film annealed at 500 OC at H2S:Ar (1:10) is the lowest compared to the other thin films. Au/CZTS/ZnS-500&ZnS-550/i-ZnO/AZO solar cells that is modelled by SCAPS simulation. The increase of the shallow donor defect density (ND) and Auger electron/hole capture coefficient that deteriorated photovoltaic performance. After Auger electron/hole capture coefficient=10-24 cm6 /s, there are recombined that more electrons from the charge carriers formed in ZnS thin film annealed at 500 OC at H2S:Ar. SnO2 intermediate layer, is placed between CZTS and ZnS layers, caused more charge separation at the two interfaces and increased V oc and efficiency of the solar cell.