Parameter Optimization for Amplitude-Modulated Resonant Mems Sensors Featuring Blue Sideband Excitation

This paper reports a strategy for further improving the sensitivity and resolution of amplitude-modulated (AM) resonant MEMS sensors subject to blue-sideband excitation (BSE). The implementation of BSE on a vacuum-packaged resonant accelerometer demonstrates that the AM sensitivity changes with a range of BSE parameters, i.e., the amplitude and frequency of the BSE signal. Therefore, optimized BSE parameters are employed for improved performance of the resonant accelerometer. As a result, the AM sensitivity can be enhanced by over 8-fold, from 1.2 V/g to 9.7 V/g; and the noise floor can be reduced by approximately 85%, from 16 μg/rtHz to 2.5 μg/rtHz, compared to raw BSE without optimization. This work shows a further investigation of BSE and represents an important step toward further advancing AM-based resonant MEMS sensors, including but not limited to atomic force microscopy (AFM).