Pull-in experiments on electrostatically actuated microfabricated meso scale beams

We report on the results of characterization and modeling of electrostatically actuated meso scale beams. The beams with clamped ends were 5000 μm long, 150 μm thick and 10, 12 and 15 μm wide and were operated by a parallel plate electrode located at the distance of 20 μm from the beam. The devices were fabricated using deep reactive ion etching (DRIE) from a silicon on insulator (SOI) wafer with 150 μm thick device layer. The beams were operated in ambient air conditions and the voltage–displacement dependence was built using image processing. In addition, pull-in behavior of the beams was modeled using several approaches, starting from geometrically nonlinear shallow Euler–Bernoulli beam model and up to fully coupled nonlinear large deflection three-dimensional anisotropic elasticity finite elements simulations. Excellent agreement between the results provided by the models and the experimental data was observed. The results of the work demonstrate an ability to achieve large displacements in simple meso scale beam structures and provide a reliable experimental reference for double clamped beams actuated by a parallel-plate electrode.