Influences of MEMS Fabrication Tolerance on the Sensitivity of the Weakly Coupled Resonators

A new sensing mechanism based on mode localization phenomenon has been applied to various resonant sensors in recent years, which shows high sensitivity and good robustness, and is compatible with the Micro-Electromechanical Systems (MEMS) fabrication technology. In this paper, the influence of fabrication tolerance on the sensitivity of the four degree of freedom (DoF) weakly coupled resonators (WCRs) with two types of coupling beam was simulated by the finite element software COMSOL. The simulation results show that the sensitivity of WCRs changed with the change of coupling beam width and the sensitivity of the WCRs with “E” coupling beam is less affected compared with the WCRs with “bridge” coupling beam. WCRs with two types of coupling beam are measured under open-loop circumstance and the experiment results show that the sensitivity difference between the designed value and measured value is smaller for the WCRs with “E” coupling beam which verified that the WCRs with “E” coupling beam is less affected by the fabrication tolerance.