Analysis of RF-MEMS switches in failure mode: Towards a more robust design

We present comprehensive theoretical and experimental investigations on one of the most relevant failure mechanisms in RF-MEMS switches, namely electrically induced stiction. In particular, we analyze an RF-MEMS switch equipped with an embedded active thermal recovery appliance by deriving and applying a 3D, problem-adapted, coupled finite element (FE) model including all relevant mechanical, electrical, thermal, and fluidic effects. The accuracy and predictive power of the simulations is ensured by a dedicated calibration procedure based on highly accurate characterization techniques such as white light interferometry and laser Doppler vibrometry. Applying the calibrated model, we studied the switch operation during failure and recovery in all details and identified the most important design parameters affecting its reliability with a view to improving the recovery capability as well as optimizing the overall performance towards a more robust switch design.