A new insight into the vibrational modeling of contact mode for atomic force microscope beams in various immersion ambiances.

Abstract

In this article, the vibrations of V-shaped beam as the most usable atomic force microscope (AFM) beam in contact mode has been modeled using finite element method. This work is a fundamental issue for contact resonance AFM. We have considered carbon tetrachloride (CCL4 ), methanol, acetone, water, and vacuum the immersion ambiences. For modeling of the beam dynamics, both of the Timoshenko and Euler-Bernoulli beam principles have been used. For presenting the best theoretical model all specifications for AFM beam and sample surface has been assumed. The outcomes show that by raising the interaction force between AFM beam and sample surface, the resonant frequency increases. By diluting the liquid surroundings, the resonant frequency and amplitude of frequency response functions (FRF) of vertical movement increase. The amplitude of FRF increases by raising the beam thickness and rectangular part breadth, but reduces by increasing the rectangular and tapered part lengths. The resonant frequency reduces by boosting the rectangular and tapered parts lengths and rectangular part width, but raises by increasing the beam thickness. Theoretical model in attendance and lack of tip-sample interaction force have been evaluated with experimental works for vacuum and water as the immersion ambiances. Results show good agreement.