Preparation and characterization of sodium-doped SnS2 semiconductor thin films for optoelectronic applications

Tin (Sn) and sulfur (S) are abundant in nature and environmentally friendly elements. The SnS2 compound consisting of these elements has inherent n-type electrical conductivity and a direct- transition band gap of approximately 2.2 eV. Therefore, this compound is a very promising material for visible light optoelectronic applications. In this study, SnS2thin films were prepared by the sol-gel chemical solution method. Sodium chemical was added to the solutions at molar rates of 1%, 2%, 3%, and .4%, respectively. It is known in previous studies that sodium doping significantly improves the physical properties of films such as optical, electrical and structural. In this study, the morphological, structural, optical and some electrical properties of SnS2 films were examined depending on the amount of sodium doping. According to X-ray diffraction (XRD), scanning electron microscope (SEM), UV Vis spectrometry and Hall measurement results, particle sizes, XRD peak intensities, forbidden band gaps and electrical conductivity types change with sodium doping. While samples with 1% and 4% Na doped films coated on p-type silicon substrate do not show heterojunction diode characteristic structure, 2% and 3% Na doped SnS2films show n-type features and show excellent diode characteristics with silicon. The results obtained show that sodium-doped SnS2films can be used in optoelectronic applications.