Tri-electrode MEMS electrostatic actuator with lower control voltage and higher stroke for actuator array implementations

Abstract Employing a tri-electrode actuator in place of a conventional parallel plate electrostatic actuator, can enable significantly lower control voltage operation for applications such as deformable mirrors or MEMS switches. The effect of the tri-electrode design parameters, including intermediate electrode spacings, background electrode voltage and gap spacing between the driving electrodes, are studied. It is shown possible to reduce the control voltage by approximately two times for a unipolar voltage supply, and four times for a bipolar supply. Extension of travel range before snap-down of 70% is shown.