Design and Simulation of Stepped Microcantilevers for Energy Harvesting Applications

MEMS piezoelectric energy harvesters have captivated greater attention due to their advantages such as higher energy density, no need of external power, and ease of integration with other micro devices. It can capture the vibration energy of the environment to realize the self-powered micro and small power electronic devices. In this work, the influence of structural parameters on the performance of energy harvester is analyzed to improve the output voltage and efficiency. Three designs namely rectangle, single-stepped and double stepped rectangular microcantilevers are compared. Zinc oxide (ZnO) is used as a piezoelectric material because of its CMOS compatibility and eco-friendly nature. All the proposed structures are designed and analyzed using COMSOL Multiphysics. Among all the designs, double-stepped rectangular microcantilever gives an increased output voltage by 21,928.5% and increase in resonant frequency by 22% for the same length.