Energy harvesters exploiting vibrational and mechanical energy sources are promising building blocks for the realization of sustainable energy systems to be employed in different application environments including indoor and harsh environments as well as in living systems and human body.
Piezoelectric transducers are a good choice for such application due to the ability of piezoelectric materials to directly convert applied strain energy into electrical energy. Aluminum nitride (AlN), by virtue of its good piezoelectric and dielectric properties, CMOS technology compatibility and biocompatibility is a good candidate to realize compact and efficient piezoelectric devices based on microelectromechanical systems (MEMS) technologies. It can be also effectively deposited by low temperature and low cost processes like sputtering technique on soft/flexible substrates thus enabling the fabrication of compact and lightweight microgenerators. The development of AlN-based microgenerators find application in wireless sensor nodes to be deployed in remote locations and self-powered systems for portable and wearable electronics or implantable biomedical devices thus overcoming problems related to the employment of conventional batteries such as toxicity, limited lifetime and periodic replacing/recharging operations.
This research line aims at the development of AlN-based microgenerators/nanogenerators capturing low level-low frequency vibrations, realized on different material platforms including Si-based substrates and soft substrates.
Current research work concerns the realization of flexible biomechanical microgenerators/nanogenerators and high performance Si-based vibrational energy harvesters by introducing new device architectures and by improving piezoelectric AlN thin film properties.
This activity is carried out in the frame of a collaboration agreement with the Center for Biomolecular Nanotechnologies of the Istituto Italiano di Tecnologia.