ibration Analysis of an AFM microcantilever with sidewall and top surface probes based on the couple stress theory

Document Type : Research Article

Authors

Abstract

In this paper, the resonant frequency and sensitivity of vibration modes of an atomic force microscope (AFM) with an assembled cantilever probe (ACP) are analyzed utilizing the modified couple stress theory. The proposed ACP comprises a horizontal microcantilever, a vertical extension and two tips located at the free ends of the cantilever and the extension, which make AFM capable of scanning the top surface and the sidewall of the sample, simultaneously. To derive the exact solution of the proposed ACP vibration behaviour, the horizontal cantilever is modeled as two beam. Having obtained the equation of motion, boundary and continuity conditions, the resonant frequency and sensitivity are studied. The results predicted by the current theory are compared to those obtained by the numerical methods presented by Kahrobaiyan et al. and the comparison shows that there is some errors in the numerical method results. The results of the couple stress theory are also compare with those of the classical beam theory. The evaluation indicates that the vibration behaviour of the proposed ACP is completely size-dependent.

Keywords


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