Piezoelectric MEMS resonator with magnetic tip mass for energy harvesting from ultra-low intensity magnetic fields

This article addresses the limitation in the implementation of the Internet of Things (IoT) due to its energy dependence on batteries. The central focus of this work is the development and characterization of a magnetoelectric (ME) energy generator for IoT, which combines a piezoelectric microelectromechanical system (MEMS) with a magnetic mass to interact with ambient magnetic fields (MFs). The device's efficiency is validated through finite element modeling (FEM) simulations and electrical characterization. Its applicability in environments with residual magnetic fields, such as near common household appliances, highlights its viability. Specific results, such as a maximum generated power of 0.55 µW, corresponding to a power density of 9.19 µW/cm³, for a magnetic field strength of 5 µT, emphasize its ability to address energy challenges and promote the sustainable autonomy of IoT. [Display omitted] •A new MEMS device for harvesting energy from magnetic fields with ultra-low strength has been proposed.•The device consists of a cantilever resonator fabricated with an SOI wafer and a magnetic tip mass.•The first prototype obtains a maximum power density of 9.19 µW/cm³ for a magnetic field of 5 µT, corresponding to a current of 15 A carried by a straight conductor at a distance of 60 cm.