Atomic Resolution Imaging of ReS2 by AFM/LFM

AFM and LFM images were obtained for the first time on the layered dichalcogenide rhenium disulfide (ReS2. ReS2 is of special interest for the investigation of the AFM/LFM imaging process, as the rhenium and the sulphur sublattices have different structures and as the surface consists of alternating rows of sulphur atoms with different height. The AFM/LFM images show typical signs of atomic scale friction like scan hystereses and saw-tooth profiles. In most cases, a dominating stick and slip behaviour of the cantilever tip is observed, leading only to elementary cell resolution instead of atom-by-atom resolution in both the AFM and the LFM images. However, if the atomic-scale stick and slip processes are suppressed by applying a z-modulation technique, atom-by-atom resolution is obtained. The the lattice constants being in good agreement with the x-ray data.