Electrostatic comb-drive actuator for MEMS relays/switches with double-tilt comb fingers and tilted parallelogram beams

MEMS relays/switches have been some of the most interesting hotspots in all kinds of MEMS devices for decades. Electrostatic actuation is the most popular actuation principle. A novel in-plane electrostatic comb-drive actuator for MEMS relays/switches was designed and fabricated. Double-tilt comb fingers and tilted parallelogram beams were proposed to achieve the requirements of MEMS relays/switches. The restoring force curve, actuation force curve, and pull-in voltage were measured. Double-tilt fingers were found to have a larger actuation force than traditional rectangular fingers, and the pull-in voltage was decreased by 25% by replacing rectangular fingers with double-tilt fingers. In addition, tilted parallelogram beams provided a convex upward restoring force curve, which was more suitable for MEMS relays/switches than the conventional force curve.