Vibration response of an atomic force microscopy piezoelectrically actuated microcantilever in liquid environment

Piezoelectric microcantilevers (MCs) are a new generation of atomic force microscopy (AFM) beams. They are capable of imaging at a high speed and consuming low energy. These MCs are also built commercially, with non-uniform geometry; and they can be utilised in different environments (gases and liquid). The objective of this Letter is to investigate the vibration behaviour of these types of MCs in liquid. The modelling of the MCs´ vibrating motion has been carried out by using the non-uniform beam model, and also by the proposed lumped mass model consisting of three spheres. The obtained results of these two models are compared with each other and with the experimental results. In addition, the effects of liquid mechanical properties, the distance of the MC to the sample surface and also the MC inclined angle at higher fundamental modes are investigated. Sensitivity analysis was performed through the Sobol method to study the effect of the MCs´ geometrical dimensions on Reynolds number. Such information can be used to choose appropriate parameters to apply an AFM piezoelectric MC in a liquid environment.