Compositional, structural, morphological, and optical characterization of magnetron sputtered CZTS thin films from various argon flow rate

In this study, CZTS thin films were fabricated by sputtering a single quaternary target followed by a sulfurization process, the compositional disparity in the sputtered films and sulfurized samples at different argon flow rates was investigated by EDX. The prepared CZTS thin films are then characterized by XRD, Raman scattering, SEM, and UV–Vis spectroscopy. It shows that the CZTS thin film deposited at an Ar flow rate of 300 sccm has the most Cu-poor and Zn-rich composition and the highest level of crystallization. Fewer voids are also observed in the film sputtered at 300 sccm of flow rate and the band gap energy of fabricated CZTS thin film is around 1.5 eV. These results indicate that compositional variation in the sputtered CZTS thin films controlled by the Ar flow rate has a significant impact on the properties of sulfurized CZTS thin films.