Development of tin (II) sulfide nanostructured films with uniform surface morphology by two-step growth process

Tin (II) sulfide (SnS), one of the most abundant materials, is being considered as an absorber material for the development of low-cost and nontoxic solar cell devices. In this direction, we have developed nanocrystalline films of SnS with uniform morphology on different substrates by adopting two-step thermal evaporation process. The surface studies show that irrespective of substrate nature, the as-grown SnS films possess uniform surface-morphology with well-defined facets. Structural studies reveal that SnS films grown on various substrates possess an orthorhombic crystal structure. However, as compared to other substrates, the structures developed on sapphire and copper exhibit 〈010〉 as preferential growth direction. From the electrical measurements, it is noticed that the films deposited on highly-conductive substrates consist of low electrical resistance, whereas the films are slightly resistive on insulating substrates. Based on these investigations it is emphasized that high-quality SnS films can be developed with uniform morphology on any substrates by adopting our two-step process.