Mechanical behavior of a novel resonant microstructure for magnetic applications considering the squeeze-film damping

The mechanical behavior of a novel resonant microstructure for magnetic applications through analytical and finite element (FE) models is presented. The squeeze-film damping is included with the development of a theoretical model which considers the parallel and transversal beams of the resonant structure. The response of the microstructure is obtained considering various magnetic fields orientations, and AC excitation currents with different magnitudes and frequencies. The microstructure has thin beam elements of polysilicon, 1.5 μm thickness by 20 μm width. It is suspended by air-gap of 2.5 μm and operates in the first torsional mode taking advantage of the Lorentz force principle. The analytical and FE results indicate a linear behavior of the microstructure deflection with a low consumption of AC current (574 μA) caused for 2 V AC voltage. Optimum response obtained using the mathematical analysis was 530 nm/Tesla with the magnetic field parallel to the microstructure (θ = 90° and α = 0°). These results show good agreement with the FE models.