Authors: X. Rottenberg, B. Nauwelaers, W. De Raedt, D. Elata
Affilation: IMEC, Belgium
Pages: 501 - 504
Keywords: electrostatic, MEMS, high-stability, numerical simulation
This paper presents a novel high-stability algorithm for the simulation of the electromechanical actuation of electrostatic MEMS devices. Its stability improves on that of voltage- and charge-drive algorithms. It further offers a purely electrical simulation alternative to previous work  based on a mechanical domain excitation to drive the simulation. Key in our algorithm are the use of a local charge density as driver for an adapted relaxation algorithm and the adequate selection of the bias node in the mesh. The high stability of this algorithm allows probing the electromechanical equilibrium locus way beyond the voltage-drive and charge-drive pull-in instabilities. The new algorithm facilitates investigation of the effect of dielectric charging in deformable electrostatic MEMS devices and especially the narrowing of their equilibrium locus due to dielectric charging non-uniformities . We implement this algorithm in 2D for clamped-clamped beams of rectangular cross-section and take into account, among other things, distributed dielectric thickness, permittivity, rest air gap, actuation electrode and linearly distributed dielectric roughness.