Optimization of stress induced bending in mems based suspensions

The suspended membrane is currently becoming the trend in Micro-Electro-Mechanical Systems (MEMS) devices. For example, in tunable Fabry-Pérot (FP) Filter, the suspended membrane can be used as a top moveable mirror. The parallelism of the suspension holding the membrane is crucially important, as output characteristics of the filter highly depend on it. However, the adverse effect of residual stress of the material causes bending in the suspension which limits the performance of the FP filter. Therefore for high performance of FP filter, the stress-induced bending must be minimized. This paper reports a novel stress optimized multilayer Suspension(s) design by using Finite Element Method (FEM).In which the bending of the suspension is reduced to 76 nm form several μm, for typically used suspended membrane dimensions.