Towards an evaluation of stiffness parameters of Micro-beams

Microfabricated devices are widely used as sensors, actuators and resonators. The performance of these devices is influenced by the process used for microfabrication and machining. Several models are available in the literature to predict the static and dynamic behavior of MEMS devices. While most of the reported models neglected the effect of flexible boundary conditions on the overall performance of the microdevices, some reported works showed that the characteristics of the micro-beams are significantly influenced by the unavoidable flexibility at the boundaries. Therefore, several recent studies considered the real support conditions by introducing spring elements at the boundary. The stiffness parameters were then estimated by fitting the numerical results with experimental measurements. There is some discrepancy between the stiffness values reported in different studies for the same microbeam. This work also presented a numerical finite element model to investigate the effect of the support on the equivalent stiffness parameters that represent real boundary conditions.