Structural, optical, and magnetic properties of Sn-doped ZnS thin films: role of post-annealing

Tin-doped zinc sulfide was coated onto glass plates and subjected to a post-air annealing treatment at 300 °C for 2 h. The air-annealed thin films were characterized for observing the tailoring in structural, surface, chemical, optical, photoluminescence, and magnetic properties due to annealing. The properties of thin films after air-annealing were compared with as-synthesized Kumar et al. (J. Supercond. Novel Magn. 32(6), 1725-1734, 2019), and vacuum-annealed Kunapalli et al. (Opt. Mater.114, 110961, 2021) thin films. Annealing in presence of air leads to finer crystallite structures of ZnS thin films. The air annealing also enhanced the transmittance property of the thin films. Two prominent peaks at 420 nm and 440 nm were observed in photoluminescence spectra. From magnetic studies, it was found that the films were paramagnetic in nature, and magnetization increased with an increase in the applied field.