A MEMS inertial switch with electrostatic force assistance and multi-step pull-in for eliminating bounce and prolonging contact time

A novel MEMS inertial switch with electrostatic force assistance and multi-step pull-in behavior has been designed, which can help the electrodes weaken the bounce and keep a long contact in the inertial switch before the leakage of electricity ends compared with the traditional rigid contact between electrodes. The dynamic switching and pull-in performance is simulated by finite element method. The designed structure is completed by multi-layer metal electroplating based on Surface micromachining technology. Finally, the fabricated device is tested by dropping hammer system. It's indicated that compared to the inertial switch with electrostatic force assistance has no bounce behavior, and realizes ~512μs long stable contact compared to that without the applied electrostatic force.