Vibration based energy harvester employing ZnO film on the stainless steel substrate

Abstract

We developed the energy harvester employing piezoelectric zinc oxide (ZnO) thin film for application to large vibrational amplitude. To ensure the fracture toughness, stainless steel (SUS304) was employed as a substrate. Also, to prevent the electrical breakdown due to the pinholes in the ZnO film, conformal silicon oxide (SiO2) layer was inserted between the ZnO film and top electrode. By inserting the SiO2 layer, power efficiency was much enhanced. As a result, a generated power of 150 nW was obtained when acceleration and load resistance were 0.7 m/s2 and 670 k, respectively. © 2013 The Institute of Electrical Engineers of Japan.