Effect of Annealing on Optical Crystallinity and Gas Sensing Characteristics of Tin Monosulfide Thin Films Deposited by DC Sputtering

Tin monosulfide (SnS) was prepared via DC magnetron sputtering on glass substrates and annealed at two temperatures (200, 300) degrees C. The annealing effect on crystallinity, optical and gas sensing characteristics of Tin monosulfide films were examined. The morphology and structure of creating SnS thin films have been researched via scanning electron microscopy (SEM), X-ray diffractions (XRD), and Atomic Force Microscopy (AFM). XRD results explain that the increasing annealing temperature from 200 degrees C to 300 degrees C caused an increase incrystallite size, while the Microstrain and the dislocation density werereduced. SEM showed that the increasing in the SnS cluster distribution with particle size increases with increasing the annealing temperature. Optical properties provethat the energy gap decreases 2.185 eV to 1.967 eV as the annealing temperature increasesfrom 200oC to 300oC, and the annealed samples exhibited enhanced gas sensitivity up to 75%