Design and measurement of AFM probe based on MEMS resonator

In order to effectively prompt the resonance frequency and the quality factor of atomic force microscope (AFM) probes simultaneously, a novel oscillating probe based on a I2 shaped MEMS resonator was conceived, designed, fabricated and evaluated. To further improve the imaging capability of this kind of probe, structure design and measurement improvements were studied and presented in this work, including new detection scheme based on simple differential measurement and using locally doped piezoresistors at maximum strain locations. Experimental results showed that with these improvements, the feedthrough coupling effect between driving and sensing is effectively eliminated and the measurement sensitivity is improved by at least 10 times.