System-Level modeling of silicon microphones including distributed effects

We present a hierarchical modeling methodology, which combines short simulation times with the attention to detail as provided by finite element-based techniques. It enables predictive simulation of micro-devices even if exhibiting complex geometries like the MEMS microphone considered in this work. The challenge to properly account for mechanical, electrical and fluidic effects including their respective couplings has been solved by applying a mixed-level approach realized in a commercial system-level simulation environment. This enables to systematically include not only lumped but also distributed effects, like viscous damping and inhomogeneously distributed electrostatic forces. Applying the calibrated and validated model we obtain important microphone characteristics and, moreover, insights into distributed phenomena affecting the device operation. Hence, this constitutes a powerful tool for re-design and optimization as well as for the development of new prototypes.