Abstract
We fabricated piezoelectric MEMS energy harvesters of PZT thin films on the microfabricated stainless steel cantilevers. The 2.5-μm-thick PZT thin films were directly deposited by RF-magnetron sputtering. Direct deposition of PZT thin films can reduces the complexity of the fabrication process of the piezoelectric MEMS energy harvesters. Furthermore, because of strong fracture toughness of stainless steel, the thickness of the cantilevers could be as thin as 30 μm. We confirmed strong diffraction peaks corresponding to pervskite PZT without a pyrochlore phase by XRD, which indicates that the polycrystalline PZT films with pervskite structures were grown on stainless steel cantilevers. We evaluated the power generation performance of the unimorph cantilever (7.5 mm-long, 5.0 mm-wide) with the tip mass of 2.5×10^<-5> kg. The averaged output power reached 6.0 μW at 10 m/s^2 and a low resonant frequency of 367 Hz.
