Single step electrochemical deposition for the fabrication of CZTS kesterite thin films for solar cells

The high absorption coefficient and direct optical band gap of a kesterite Cu2ZnSnS4 (CZTS) makes it very promising absorber material in the manufacturing of high efficiency and low-cost thin film photovoltaic cells. Single step electrochemical deposition of CZTS quaternary compound thin films on Indium tin oxide (ITO) substrates is reported in this work. The films were obtained from aqueous solutions at room temperature. The key objective of this work is to examine the effect of annealing temperature on CZTS thin films. Sulfurization of thin films was performed under different temperature range from 400 °C to 550 °C. Good crystal structure was achieved at temperature 500 °C with the complexing agent of trisodium citrate. Deposited films material composition was evaluated by analyzing UV–visible spectroscopy, EDS, FE-SEM and XRD. The thin film with good morphological, structural and optical (1.51 eV) properties was achieved at temperature 500 °C. The results reported in this work will provide an imperative guideline for efficient low-cost design of CZTS thin films.