Gamma irradiation effects on the electrical and structural properties of SnS/ITO heterojunction for radiation dosimetry applications

This study presents the synthesis and characterization of SnS/ITO thin films for gamma radiation sensing applications. The films were fabricated via a spin-coating method, and X-ray diffraction (XRD) confirmed their polycrystalline trigonal phase. The as-deposited SnS/ITO exhibited a bandgap of ∼1.75 eV, which decreased to ∼1.65 eV after exposure to 5 kGy of gamma irradiation. Electrical properties were evaluated through dark current–voltage (I–V) measurements, showing that the forward-bias turn-on voltage decreased from 2.45 V to 2.23 V with increasing radiation, while current levels increased. The heterojunction's ideality factor was greater than one and decreased with higher gamma doses. Additionally, saturation current, series resistance, and barrier height varied with irradiation, reflecting changes in defect density and charge carrier trapping at the interface. The response of the SnS/ITO system to gamma radiation was analyzed via the generation of carriers in the depletion region. These findings highlight the potential of the fabricated heterostructure as an effective radiation sensor and dosimeter, owing to its responsive thin-film layers.