Piezoelectric Cantilever Micro-accelerometer Sensitivity Enhancement using Uniform Stress Distribution

Nowadays, microelectromechanical (MEMS) accelerometers are diversely used in broad industrial fields due to their low power consumption as well as simple reading circuit and fabrication process. In this study, a MEMS-based piezoelectric microaccelerometer is presented with dramatically increased sensitivity that was achieved by creating a uniform stress distribution in its piezoelectric layer. As compared to other similar microaccelerometers, however, this microaccelerometer exhibits less cross-axis sensitivity. The frequency response and resonance modes of the proposed microaccelerometer were also studied, and its output characteristics determined. The Von Mises stress analysis showed that the proposed design does not fail within an acceleration range of ±45g. In addition, fatigue analysis showed that the proposed microaccelerometer was fatigue-proof when placed under a cyclic acceleration with an amplitude range of ±30g and was capable of withstanding more than 3 million cycles upon being exposed to an alternate acceleration with an amplitude range of ±45g.