Microelectromechanical z-axis out-of-plane stopper

Abstract

The present invention relates to a microelectromechanical structure, and more particularly, to systems, devices and methods of incorporating z-axis out-of-plane stoppers that are controlled to protect the structure from both mechanical shock and electrostatic disturbance. The z-axis out-of plane stoppers include shock stoppers and balance stoppers. The shock stoppers are arranged on a cap substrate that is used to package the structure. These shock stoppers are further aligned to a proof mass in the structure to reduce the impact of the mechanical shock. The balance stoppers are placed underneath the proof mass, and electrically coupled to a balance voltage, such that electrostatic force and torque imposed by the shock stoppers is balanced by that force and torque generated by the balance stoppers. This structure is less susceptible to mechanical shock, and shows a negligible offset that may be induced by electrostatic disturbance caused by the shock stoppers.