Electromechanical coupling analysis for MEMS featured by stepped-height structure and concentrated load

A method is presented for MEMS's electromechanical coupling analysis after a discussion about the limitation of traditional methods. Models for stepped-height beam subjected to arbitrary concentrated force or moment, and models for stepped-height circular plate subjected to central concentrated force are developed. Deflections and pull-in voltages obtained from the new method are in good agreement with Ansys FEM simulation results. The new method is also applicable to beam and circular plate with unvaried or smoothly varied height and under distributed load, with an obvious calculation speed advantage over finite difference method when strict convergence criterion is demanded. As same as a numerical method, it can replace finite difference method in electromechanical coupling analysis of beam or circular plate with more functions and better performance.