Pull-in suppression and torque magnification in parallel plate electrostatic actuators with side electrodes

In this paper we introduce a new electrostatic actuator that provides a large increase in neutral position (no rotation) torque and suppression of pull-in compared to a conventional parallel-plate structure. The actuator geometry incorporates raised electrodes on the side of the rotating element that generate torque versus angle behavior much different than convention parallel plate actuators. Using this electrode configuration we have demonstrated 17-degree stable mechanical rotation on large (950 /spl mu/m diameter) mirrors with 100 V single ended drive-a rotation of 60% of the gap. Driving the mirrors with a differential drive scheme we have demonstrated stable 8-degree rotation with as little as /spl plusmn/18 V.