Design and implementation of a bistable microcantilever actuator for magnetostatic latching relay

This paper presents the design, fabrication, and implementation of a microcantilever actuator with magnetostatic latching for performing low power bistable relay applications. This unique bistable feature consists of a low-stiffness torsion/cantilever beam system with circular-shaped support and a permanent magnet for holding the closed state with a permalloy soft magnetic circuit. The special circular support is designed to enhance the stiffness of the overhang beams. First, mechanical modeling of the leveraged torsion/cantilever beams was performed by Castigliano’s theorem so as to deduce the spring stiffness of system. Then the device has been prepared by a laminated photoresist sacrificial layer process (LPSLP). Finally, mechanical performance was characterized by atomic force microscopy (AFM), combined with finite element simulation using ANSYS™ package and analysis model as well. Switching between two stable states of the microactuator was successfully validated with WYKO NT1100 optical profiling system.