Authors: M. Turowski, Z. Chen and A. Prezekwas
Affilation: CFD Research Corporation, United States
Pages: 241 - 244
Keywords: MEMS, air damping, squeeze film, 3D simulation, circuit/behavioral models
The paper presents simulations of air damping in MEMS, including squeeze-film and viscous dissipation, using different level models: 3D numerical solution of Navier-Stokes equations (using CFD-ACE from CFDRC), and circuit/behavioral model (in SPICE and Saber/MAST formats). Results of the squeeze film compact model, based on an equivalent circuit, agree very well with the 3D results even for very large amplitudes of plate motion (up to 90% of the nominal gap), accompanied by significant changes of pressure (up to 15 times bigger than the static ambient pressure). All previous squeeze film simulations published by other authors were limited to small amplitudes and small pressure changes only. To derive behavioral models for torsional micromirrors, comb-drive resonators, and moving plates with holes, a comprehensive analysis of shear and squeeze forces acting on moving MEMS elements has been performed.