Out-of-plane vibration measuring technique based on dynamic AFM

摘要

The theory modal of dynamic AFM probe under vibration surface and also the corresponding normalized form are set up, while the frequency range of the out-of-plain vibration of the sample (i.e. the frequency ratio of the sample vibration frequency and the probe's working frequency in the normalized form) that dynamic AFM can measure is the most important to analyzed. Runge-Kutta numerical method is used to analyze the feasibility and the bandwidth of AFM vibration measuring technique. Taking fixed-fixed nanobeam resonator under electrostatic actuation as the measured sample, its out-of-plane amplitude frequency response characteristics are measured using micro-laser Doppler vibrometer (microLD), scanning tapping mode (TM) AFM and force-curve tapping mode (F-TM) AFM respectively. The accordant resonant frequency of 1.73 MHz are gained and the vibration-amplitude test results have small deviations. The frequency speciality of vibration measurement errors of dynamic AFM related with the quality and strength of the vibration sample is strongly put up.