Effect of contact position and tip properties on the torsional vibration responses of atomic force microscope cantilevers
In this paper, the characteristic equation of the torsional vibration for an AFM cantilever with different contact position is given. By considering the effects of length, mass and contact position of the tip the resonant frequency and amplitude of the torsional vibration of the cantilever were analyzed. Because the tip is not exactly located at one end of the cantilever, the cantilever is modeled as two beams. The results show, that the effect of increasing the contact position on the resonant frequency are apparent for the high-order modes. Increasing the tip length, effective mass and contact stiffness can decrease the resonant frequency.