Design and Fabrication of Flexible Piezoelectric Generators Based on ZnO Thin Films

The piezoelectric transducer for vibration-energy harvesting is constructed of a piezoelectric layer, bottom electrode and a top electrode. In order to obtain an appropriate transducer for the low-frequency operating; environmentally-friendly and long-term, the flexible substrate, the piezoelectric layer, and the additional mass-loading have been investigated thoroughly. Firstly, flexible piezoelectric harvesters based on ZnO (Zinc Oxide) thin films for self-powering and broad bandwidth applications. The design and simulation of a piezoelectric cantilever plate was described by using commercial software ANSYS FEA (finite element analysis) to determine the optimum thickness of PET substrate, internal stress distribution, operation frequency and electric potential. A modified design of a flexible piezoelectric energy-harvesting system with a serial bimorph of ZnO piezoelectric thin film was presented to enhance significantly higher power generation. This high-output system was examined at 15 Hz. The maximum DC (direct current) voltage output voltage with loading was 3.18 V, and the maximum DC power remained at 2.89 µW/cm2. Secondly, this investigation fabricates double-sided piezoelectric transducers for harvesting vibration-power. The double-sided piezoelectric transducer is constructed by depositing piezoelectric thin films. The Ti (titanium) and Pt (platinum) layers were deposited using a dual-gun DC sputtering system between the piezoelectric thin film and the back side of the SUS304 substrate. The maximum open circuit voltage of the double-sided ZnO power transducer is approximately 18 V. After rectification and filtering through a 33 nF capacitor, a specific power output of 1.3 µW/cm2 is obtained from the double-sided ZnO transducer with a load resistance of 6 M?>