EXPERIMENTAL VALIDATION OF MODELLING OF THE MECHANICAL BEHAVIOUR OF MICROBEAM ELECTROSTATIC ACTUATORS FOR RADIO-FREQUENCY MEMS

Abstract

A preliminary experimental validation of the numerical models previously developed by the authors, to predict the mechanical behaviour of microelectrostatic actuators, is here presented. Microcantilevers are currently used in RF-MEMS design, thus motivating this research activity. The analysis investigates the static behaviour of a set of plane microcantilevers, bending in the plane of the wafer. This investigation points out the relevant role of the nonlinear geometrical behaviour, exhibited under large displacement condition, on the overall behaviour of the structure. A coupled-field numerical approach is herewith experimentally validated, by means of a Fogale Zoomsurf 3D. Model performance is evaluated on pull-in prediction and on the curve displacement vs. voltage. In particular, experimental results are compared to the FEM nonlinear solution performed by a commercial code and to the original FEM non-incremental approach developed by the authors.