Experimental and Numerical Investigation of CZFS Thin Film Absorbers for Photovoltaic Applications

Copper zinc iron sulfide (CZFS) is an earth-abundant semiconductor of interest for use as an absorber layer in thin-film photovoltaic devices. In this study, chemical bath deposition (CBD) a non-vacuum, low-cost technique was used to synthesize CZFS thin films. The structural, optical, and microstructural properties of the films were characterized using X-ray diffraction (XRD), UV-Visible spectroscopy, and transmission electron microscopy (TEM). XRD analysis revealed that the CZFS film possesses a polycrystalline structure with an average crystallite size of ~30.5 nm, UV-vis spectra yielded a direct optical band gap of ~1.6 eV, and TEM provided detailed insights into the film morphology. The device structure was subsequently modelled using SCAPS-1D to evaluate solar cell performance. The simulated current-voltage (I-V) characteristics and photovoltaic parameters were analyzed as a function of absorber layer thickness and interface defect density. Correlating the experimental results with the simulated device performance demonstrates that CZFS is a promising absorber layer for low-cost thin-film solar cells.