Modelling electrostatic behaviour of microcantilevers incorporating residual stress gradient and non-ideal anchors

The electrostatic behaviour of micromachined cantilevers incorporating residual stress gradient and non-ideal anchors is studied in this work. Using finite-element simulation data, behavioural models that predict the electrostatic deflection and pull-in voltage of such structures have been established. The models account for the effects of residual stress gradient and real supports on the mechanical behaviour of the microcantilevers, and have been validated via comparison with experimental data. For the deflection models, the level of correlation achieved was within 7%, and in the case of pull-in voltage analysis, the calculated and measured values agree to within 4%. The completed models offer an efficient means of design, analysis and optimization of cantilever-based electrostatically actuated MEMS devices. They can also be utilized for material property measurement and analysis.