Macromodel-based simulation and measurement of the dynamic pull-in of viscously damped RF-MEMS switches

Three different state-of-the-art approaches are used to generate macromodels of an electrostatically actuated and viscously damped ohmic contact RF-MEMS switch. The capability of the three multi-energy domain coupled models to predict the behavior of the RF-MEMS switch is evaluated w.r.t. white light interferometer and laser vibrometer measurements. The different macromodels show very good agreement concerning the quasi-static measured pull-in/pull-out characteristics. The evaluation of the modeled viscous damping forces demonstrates that tailored physics-based models give significantly better results than simple generic models. However, all approaches fail in capturing the landing phase of the membrane during the dynamic pull-in correctly. Measurements revealed that this is due to the presence of a higher eigenmode that is activated during impact.