A resettable polysilicon MEMS-based circuit breaker

This work presents a novel resettable microelectromechanical systems-based circuit breaker (MCB) that utilizes electrostatic actuation for switching and Joule heating for reset functionality. The device integrates a dual air gap and a straight beam suspension structure to enhance contact force, reduce resistance, and improve switching efficiency. Fabricated using the PolyMUMPs process, the MCB features a polysilicon microbridge that achieves stable contact at an electrostatic actuation voltage of approximately 75 V. The circuit-interruption threshold was experimentally determined to be 14–17 mA. Experimental results further validate that the device achieves an average single contact resistance of 162.5  (Formula presented) (Formula presented), and a total MCB resistance of 325  (Formula presented) (Formula presented), demonstrating its suitability for current-limiting and protection applications.