Improve the photodetector properties of SnS thin films via nebulizer spray pyrolysis (NSP) technique for UV sensor applications

Tin-based chalcogenide semiconductors are highly promising for photodetectors due to their excellent performance and stability in UV light detectors. This study produced SnS thin films at varying substrate temperatures using the nebulizer spray pyrolysis (NSP) method to apply as UV light photodetectors. The characterization of SnS thin films investigated the influence of substrate temperature on crystallite size, morphology, absorbance, bandgap, and photosensing properties. The XRD studies showed that the thin films exhibits an orthorhombic SnS phase, with a Sn₂S₃ impurity phase appearing at a deposition temperature of 375 °C. The largest crystallite size (59 nm) was observed for the sample deposited at 350 °C. The FESEM results exhibits that the SnS thin films have a homogeneous surface with spherical-shaped grains of various sizes. UV-Vis spectroscopy reveals that increasing substrate temperature decreases the sample's bandgap value. The SnS thin films exhibits higher photosensing properties at 350 °C, with a responsivity (R) value of 17.4 × 10⁻² AW⁻¹, an external quantum efficiency (EQE) of 41 %, and detectivity ⁽D*) of 5.89 × 10⁹ Jones. The results show that the substrate temperature has a crucial role in SnS thin films, which are necessary to produce high-quality films for photodetectors.