Recent progress of piezoelectric MEMS for energy harvesting devices

Abstract

With higher integration, smaller size, and automated processes, sensors and wireless devices have seen dramatic enhancements to their quality, robustness, and reliability. Recent efforts have been made toward developing autonomous, self-powered remote sensor systems that can offer enhanced applicability and performance with cost savings. With the decrease in power requirements for wireless sensors, the application of piezoelectricity to energy harvesting has become viable. The technological challenge of realizing such a system lies in the construction and fabrication of a miniaturized vibration energy harvester. The current design of MEMS-scale devices comprises a seismic mass made of silicon connected to the substrate by a thin PZT cantilever beam. Factors relating to power improvement and reliability of the device are discussed by addressing the shape of the cantilever beam, piezoelectric mode, MEMS process, and environmental temperature. ©2010 Society for Experimental Mechanics Inc.