Aspects of dynamic force microscopy on NaCl/Cu(111) : resolution, tip-sample interactions and cantilever oscillation characteristics

Ultrathin films of NaCl on Cu(111) have been studied using a dynamic force microscope. We present images with atomic resolution at step sites on the NaCl films, Force spectroscopy measurements of the tip-sample interaction on NaCl-covered areas and the Cu substrate are analysed with respect to electrostatic, van der Waals and short-range contributions, The interaction contrast between NaCl and Cu is shown to be reflected in the oscillation characteristics of the cantilever, First results of a resonance analysis with the help of a novel digital oscillation control system are presented.