MEMS based energy scavenger with interdigitated electrodes

Abstract

MEMS-based energy scavengers have attracted industries and researchers as promising solutions to the energy crises which will certainly affect the present and future generations due to increased population and/or pollution. The capability of miniaturized energy scavengers to generate usable energy from ambient vibrations makes them a special and effective alternative to clean energy sources that can be used in many applications like point of care testing devices, and self-power micro-systems, low duty cycle applications, etc. MEMS-based energy scavenger using Zinc Oxide (ZnO) piezoelectric material for active layer is proposed here which can be used to drive the low power applications. The spin coating method with optimized speed was effectively used for ZnO deposition. Aluminum foil-based Interdigitated Electrodes (IDE) were used to ensure good flexibility, no internal defects, and crack-free movement during vibrations. The low-cost, easily available, flexible Polyethylene Terephthalate (PET) substrate used in the passive layer makes the scavenger suitable for energy harvesting from vibrations of many natural surface structures which are not flat such as clothes, human bodies, household equipment, industrial machines, etc. The MEMS-based Energy Scavenger with Interdigitated Electrodes (MEMS-ES-IDE) generated 3 V open-circuit voltage (OCV) at 60 Hz resonant frequency. Based on the obtained values of OCV, it was confirmed that the fabricated MEMS-ES-IDE would be used in a variety of low-duty cycle applications.