Finite element analysis of tunable Fabry Perot MEMS structures

Finite element modelling of the mechanical response of MEMS structures is essential for device design and optimisation prior to any fabrication steps. We present finite element modelling (FEM) and optimisation of a MEMS Fabry-Perot (FP) optical filter using a commercial FEM package. A variety of membrane geometries have been characterised in order to maximise the tunable range whilst minimising any curvature of the top reflective surface. The analysis, while directed toward a FP tunable filter, is applicable to any MEMS system that relies on the deflection of a membrane or cantilever. MEMS devices such as accelerometers, pressure sensors and mechanical actuators can all be characterised, using this approach.