Design and simulation of polysilicon micro tuning fork for ultrasonic frequency operation

The present work describes a theoretical design of a micro electro thermal resonator based on a tuning fork that can be tuned by design at ultrasound frequencies, from 30 kHz up to 200 kHz. The device is proposed on PolyMUMPS process where the minimum feature dimension is four micro meters. This design is aimed as a platform for physical or chemical sensors, operated with lower voltage than electrostatic tuning forks. The proposal is validated by a finite element analysis performed in COMSOL Multiphysics, the results show that electro thermal actuation is an alternative strategy for resonator designs without temperature restrictions with a power dissipation of 29 mW and operation voltage lower than 20 V.