Raman imaging studies on perforated MoS2 films prepared by RF sputtering method

We investigated the spatial distribution of the crystallinity for sputtered-MoS2 films by Raman imaging technique. MoS2 lattice could not be structured in as-sputtered sample prepared at room temperature. The crystallinity could be improved by thermal annealing at 630 oC in vacuum condition. However, annealed MoS2 films had two kinds of circular perforated areas on their top surface. In one area, MoS2 film was evaporated and the substrate was exposed. In another area, MoS2 films formed a hillock shape and showed tensile strain. In addition, the crystallinity was deteriorated in hillock formed area, which is due the generation of sulfur vacancies by thermal annealing.