Design optimization of MEMS piezoelectric energy cantilever device for environment vibrations harvesting

Piezoelectric MEMS cantilevers have been under strong demand in the last years. Most of them made in the thin film technology and in different configurations like unimorphs, bimorphs or multimorphs are targeted for sensor and actuator applications. Our paper is about the design optimization of piezoelectric harvesting cantilevers able to convert mechanical vibrations from the surrounding environment to electrical energy via direct piezoelectric effect. Different unimorph piezoelectric harvester geometries and materials are proposed, all employing flexure mode. All these models are simulated using CoventorWare software. A double array of cantilevers (2 × 10) is used in order to obtain a greater output power magnitude, up to ~1.46 μW.