Annealing effect on single-phase SnS film grown via spray pyrolysis method

Present paper reported on SnS films to growth via spray pyrolysis technique onto glass substrate at 350 °C temperature. One of two as-grown SnS samples was annealed at 400 °C to investigate the annealing effect on SnS properties. XRD revealed a single orthorhombic phase for both SnS samples with (020) as preferential orientation. Elemental analysis showed an increased Sn/S atomic ratio to 1.07 for annealed SnS rather than 0.95 for as as-grown-SnS. SEM and AFM analysis revealed a decrement in grain size, therefore a decrement of average roughness form 46.5 nm to 27.1 nm, as well thickness from 1200 nm to 920 nm, respectively. Annealing enhanced the SnS absorption in the visible range; however, it caused an apparent shift in absorption edge towards longer wavelengths for annealed SnS sample. SnS annealing increased the direct bandgap, carrier concentration and Hall mobility up to 1.56 eV, 6.57 × 10¹⁷ cm^− 3, and 42.91 cm²V^− 1s^− 1, respectively.