DRIE-fabricated curved-electrode zipping actuators with low pull-in voltage

This paper presents the modeling, design, fabrication and testing of monolithic electrostatic curved-electrode zipping actuators fabricated by deep reactive ion etching (DRIE). In contrast to traditional curved-electrode zipping actuators, they utilize compliant starting cantilevers to significantly reduce the initial pull-in voltage. Thus, the actuators simultaneously achieve high actuation force and large displacement at a relatively low voltage. For example, two actuators each with dimensions of 4.5 mm/spl times/100 /spl mu/m/spl times/300 /spl mu/m are used to drive a bistable MEMS relay. Both actuators provide between 3/spl sim/10 mN of force over their 80 /spl mu/m stroke. Experiments with these actuators confirm theoretical expectations.