Interpretation of tapping mode atomic force microscopy data using amplitude-phase-distance measurements

Vibrating mode force measurements, or amplitude–phase–distance measurements, have been used to experimentally investigate contrast mechanisms in tapping mode atomic force microscopy. Gelatin adsorbed on polystyrene and mica surfaces have been taken as examples to show that the amplitude–phase–distance curves and amplitude–energy loss–distance curves enable the interpretation of artifacts in height images and contrast in phase images. The principles are applicable in general to tapping mode imaging, and are discussed in the context of previously proposed theoretical models, i.e., those based on solution of equations of motion or on energy conservation.