Modelling and validation of air damping in perforated gold and silicon MEMS plates

Abstract

Dynamic behaviour of oscillating perforated plates for MEMS applications under the effect of squeeze film damping is studied. Two geometrical topology types of gold and silicon plates were manufactured with many different geometrical dimensions for the plate and the holes. The structures were electrostatically excited to vibrate at their fundamental modes and the vibration amplitudes were measured optically. The quality factors have been extracted from the measurements using the half-power method. Multiphysics FEM simulations for the structures were performed for comparison. Also, a study to characterize the air flow around the oscillating structure was performed, and a compact model was chosen to estimate the quality factor due to gas damping. Besides the damping, other dissipation mechanisms were also studied.