HOW DOES A TIP TAP

There is a demand for good theoretical understanding of the response o f an atomic force microscope cantilever to the extremely nonlinear imp acts received while tapping a sample. A model and numerical simulation s are presented in this paper which provide a very pleasing comparison with experimental results. The dependence of the cantilever amplitude and phase upon the sample stiffness, adhesion and damping are investi gated using these simulations, and it is found that 'topographic' tapp ing images are not independent of sample properties, nor will it be tr ivial to measure materials' properties from the tapping data. The simu lation can be applied to other probe microscope configurations as well .