Simulation and optimization on the squeeze-film damping of a novel high-g accelerometer

The damping characteristics of a packaged high-g accelerometer have been investigated in this paper. Firstly, a multi-segments-plates-approximate (MSPA) model on curved surface damping suitable for this component has been established to obtain the relationship between the parallel-shift-distance (PSD) of curved stop and the damping of component. Subsequently, not only the effect of the PSD of curved protection but also the impact of the characteristics of damping media on the dynamic shock response of the component has been studied with ANSYS FEM technology. Results show that the dynamic output responses of component were in reality the superposition of both the forced vibration under acceleration shock and the vibration of cantilever in its inherent frequency. With the increase of PSD, the inherent frequency vibration became outstanding in output response and both the peak output voltage and displacement of beam end increased linearly whereas its corresponding time decreased nonlinearly. The effects of damping media on the dynamic response characteristics of the component were attributed to the difference of viscosity coefficient of damping medium. Under the same other conditions, with increment of viscosity coefficient, the output response curve become smoother except for lower peak voltage. Therefore, the PSD of curved stop should be controlled between 0.5 and 0.65 μm during the fabrication of chip and if the PSD was about 0.5 μm, air would be the most suitable damping media in the packaging of the component.