Simulation and vibration test for a micro-spiral beam device

A micro-spiral beam device for the vibration-type sensor and actuator structure has been designed. To improve vibration behaviors of the micro-spiral device, beam wave motion and beam deflection need to be suppressed associated with external load. Finite element analysis (FEA) method was carried out to design a spiral beam without beam wave motion. The trapezoidal width spiral was proposed to suppress beam wave motion of a spiral device. It was found from the FEA results that beam wave motion of a spiral was effectively suppressed depend on the trapezoidal beam length and the fixed end width. The FE analysis results were applied to design the photo-mask for MEMS photolithography and MEMS photolithography processing was actually carried out using the photo-mask. Vibration test was carried out using the micro-spiral devices and was compared with the results of FE analysis results which beam wave motion was depended on the trapezoidal beam length and the fixed end width. It was proved that suppression effect of beam wave motion of the spiral device can be mainly obtained associated with the trapezoidal beam by 1.5 π and the spiral beam width at the fixed end.