Ultrasensitive resonant MEMS transducers with tuneable coupling

This paper investigates the enhanced sensitivity to external perturbations through mode localization in a coupled resonant MEMS transducer device. An energy-based framework is developed to analytically study energy localization in the MEMS device by using a novel, electrostatically-induced stiffness perturbation. Specifically, we analyze the mode localization associated with eigenvalue veering phenomenon, resulting from a symmetry-breaking perturbation in a coupled two-resonators MEMS device. The measured mode shape sensitivities are compared with predictions made by both a simplified analytical model and a more detailed Simulink model. The mode shape sensitivity to perturbations is shown to be an order of magnitude higher than that of resonant frequency shifting. The sensitivity can be further increased by decreasing the coupling strength between the two resonators, but with a reduced dynamic range of the external perturbations.