Multi-harmonic atomic force microscopy with micro cantilever incorporating the intentional internal resonance

Abstract

A new microcantilever design concept for higher harmonic atomic force microscopy, designed with intentional internal resonance, has greatly amplified the higher harmonic signals in dynamic tapping mode operation. An inner paddle coupled to the AFM microcantilever is designed to have a 1:3 ratio between the eigenfrequencies of the leading bending modes of the new cantilever system. Due to the nonlinear nature of the cantilever tip-sample interaction and the intentional internal resonance, the nonlinear energy transfers from the fundamental bending mode to the higher frequency mode. Through theoretical and experimental studies, it is shown that the higher harmonic phase term is greatly enhanced when compared to the fundamental harmonic response.