Experimental analysis and modeling of the mechanical impact during the dynamic pull-in of RF-MEMS switches

The dynamic pull-in and pull-out of an electrostatically actuated and viscously damped ohmic contact RF-MEMS switch is both measured and simulated. Three different models are used for the simulations and evaluated w.r.t. measurements performed with a white light interferometer and a laser vibrometer. The evaluation shows that all models fail in predicting the initial contact phase of the membrane correctly. Further analysis reveals that this is due to the presence of a higher eigenmode that is activated during the first impact of the membrane.