Damping effects in MEMS resonators

Abstract

Damping effects are very important in MEMS-based sensors and actuators. In this paper we use analytical models and finite element (FE) computations to quantify the energy losses due to viscous fluid damping, acoustic radiation and thermo-elastic damping. To treat the case where squeeze/slide film models can not be applied, we have implemented in a commercial FE package a new incompressible flow solver based on a gauge formulation. We are thus able to solve for full flows around complex 3D geometries in the frequency domain and predict viscous damping of resonant MEMS structures. The full methodology is exemplified on the response of a MEMS silicon resonator, including acoustic driving and piezoelectric sensing.