Large-amplitude MEMS electret generator with nonlinear spring

A MEMS electret generator with nonlinear spring has been developed for energy harvesting applications. By using hybrid high-aspect-ratio parylene springs, a large-amplitude oscillation over 1.0 mm
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has been obtained in a broad frequency range of 46-73 Hz. By using our mechanical model of the nonlinear spring, we have confirmed that the model can mimic frequency response of the mass-spring system. With the aid of electrostatic levitation mechanisms for keeping the air gap, power output of 1.0 ¿W has been obtained at 63 Hz.