A compact model for dielectric charging in RF MEMS capacitive switches

Abstract

A unified, macroscopic, one-dimensional model is presented for the quantitative description of the process of dielectric charging in radio frequency micro-electro-mechanical systems (RF MEMS) switches. The fidelity of the model relies on the utilization of experimentally obtained data to assign values to model parameters that capture the nonlinear behavior of the dielectric charging process. The proposed model can be easily cast in the form of a simple simulation program with integrated circuit emphasis (SPICE) circuit. Its compact, physics-based form enables its seamless insertion in nonlinear, SPICE-like, circuit simulators and makes it compatible with system-level MEMS computer-aided analysis and design tools. The model enables the efficient simulation of dielectric charging under different, complex control voltage waveforms. In addition, it provides the means for expedient simulation of the impact of dielectric charging on switch performance degradation. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009.