Dynamics of high quality factor force microscope microcantilevers operated in contact mode

In AFM system with contact mode operation, the surface structure is determined by measuring the variation of the microcantilever tip deflection as the tip scans across the sample. Therefore, the dynamic characteristics of the microcantilever, including the stability, rapidity and accuracy performances, are extremely important parameters in determining the performance of AFM. In this paper, we obtain the analytical expressions of the deflection, overshoot, and adjustment time of the cantilever by using the Laplace transform theorem. The influence of the intrinsic parameters on the system dynamics is discussed in detail, which provides theoretical guidance for selecting samples in the experiments. Moreover, we propose a new control method based on the velocity feedback control in order to enhance the dynamic features of the system. The results indicate that the new control method can effectively improve the dynamic characteristics of the microcantilever.