Getting adhesion force maps with an amplitude-modulation AFM in tapping mode

Abstract

Here we demonstrate how to get adhesion force maps with an amplitude-modulation AFM in tapping mode. Our method is tapping mode but it is carried out at ultra-small amplitudes in the presence of surface water layers. The tip is made to vibrated under the water layer in what we call Small Amplitude Small Set-point AM AFM. We show how this is done with an example based on the Cypher scanning probe microscope from Asylum Research. We also show that the elastic modulus can be simultaneously estimated while scanning by performing bimodal SASS. On top of being a quantitative method, it might enhance resolution.