Large angle silicon-on-insulator tilting actuator with kinematic excitation and simple integrated parallel-plate electrostatic transducer

We report on the novel architecture and operational principle of an electrostatically actuated large angle tilting microelectromechanical (MEMS) actuator with kinematic excitation. The device transforms and amplifies small linear out-of-plane motion of a parallel-plate transducer into a large angular motion of a tilting element attached to the transducer with a certain offset using an elastic torsion axis. The actuator, which is distinguished by the single layer robust architecture and incorporating the simple integrated electrostatic transducer, was fabricated from a silicon-on-insulator (SOI) substrate using a common deep reactive ion etching (DRIE) based process. Detailed modeling of the device was followed by the experimental characterization of the actuator. Large tilting angles were observed in experiments, consistenty with the theoretical prediction. An optical peak to peak angle of 37.5° was measured under relatively low actuation voltages. Our theoretical and experimental results collectively demonstate the feasibility of the suggested apporach and show that simple electrostatic actuation combined with the dynamic amplification results in efficient large amplitude operation of tilting devices.