Preparation, Characterization, and Performance Optimization of Cu2ZnSnS4 (CZTS) Absorber Layer Deposited by Sol-Gel Spin Coating Technique

This study focuses on the deposition of thin films of copper zinc tin sulphide (CZTS) on uncoated soda lime glass (SLG) substrates, followed by comprehensive characterisations using X-ray diffraction (XRD), Raman spectroscopy, and UV-V is spectroscopy. The XRD and Raman results revealed the presence of kesterite CZTS and secondary phases such as SnS (TS), ZnS, and CuSnS (CTS) of the grown thin films, providing valuable insights into the crystalline structure of the samples. UV-V is spectroscopy demonstrated that the transmittance of some of the samples exceeded 90 % in the visible region, indicating their potential for transparent and efficient electronic and optoelectronic applications. Furthermore, the effect of both thickness and annealing temperature on the optical energy gap () were studied. The allowed direct optical energy gap was found to be in the range of 2.30 to 2.94 eV for the as-deposited samples and 1.82 to 2.91 eV for the annealed samples.