Modeling of dielectric charging in RF MEMS capacitive switches

A unified, macroscopic, one‐dimensional model is presented for the quantitative description of the process of dielectric charging in RF MEMS capacitive switches. The model provides for the direct incorporation of various physical factors known to impact dielectric charging, such as surface roughness, material inhomogeneity, and electric field‐dependent conduction in the dielectric. The values of the various parameters used in the model are extracted from experimental data. The proposed model serves as a generalization of various earlier models reported in the literature for the quantitative description of dielectric charging. Its formulation is such that it can be incorporated in a straightforward manner in coupled electro‐mechanical modeling schemes for the computer‐aided analysis of RF MEMS capacitive switches.