Efficient electrostatic-mechanical modeling of C-V curves of RF-MEMS switches

The capacitance versus actuation voltage, the C-V curve, is characteristic for the steady state behavior of a RF-MEMS capacitive switch. It is imperative to have an efficient method to simulate these curves and overcome the convergence problems from pull-in and release instability that is inherent to these electrostatic actuated devices. In this paper we show how the complete CV curve can be calculated in FE code, including conditionally stable parts and zipping regions, which also comprises a non-linear contact model. Efficiency improvement by use of a reduced order model for the electrostatic domain is shown. Validity of the simulation results is shown by comparison to measurements.