Thermal actuation with piezoresistive sensing in mechanical resonators

Abstract

This report is to study the comprehensive simulation model to describe the characteristics of the thermally actuated electromechanical dog-bone resonator by the software Comsol 4.2a. The results show that the resonator in small size around 80μm*50μm*10μm can be actuated under high resonant frequency around 64MHz with desirable high Q factor around 50000. The amplitude of the mechanical vibration (Xa) due to the thermal actuation is proportional to the amplitude of the input voltage. The relative resistance change (∆R / R) caused by the mechanical vibration is proportional to the amplitude of the mechanical vibration. What is more, the amplitude response is largest at resonant frequency for the dog-bone. The most important thing is that the amplitude response at resonant frequency cannot be derived from that at low frequency by the equation Xar = Q * Xal, where Xar is the amplitude response at resonant frequency, Xal is the amplitude response at low frequency.