TY - JOUR
T1 - Flexible piezoelectric AlN transducers buckled through package-induced preloading for mechanical energy harvesting
AU - Mariello, M.
AU - Blad, T. W.A.
AU - Mastronardi, V. M.
AU - Madaro, F.
AU - Guido, F.
AU - Staufer, U.
AU - Tolou, N.
AU - De Vittorio, M.
PY - 2021
Y1 - 2021
N2 - There is a high demand for novel flexible micro-devices for energy harvesting from low-frequency and random mechanical sources. The research of new functional designs is required to strategically enhance the performances and to increase the control on mechanical flexibility. In this work we report the fabrication and characterization of bi-stable and statically balanced thin-film piezoelectric transducers based on Aluminum Nitride (AlN). The device consists of a piezoelectric layer sandwiched between two thin Molybdenum electrodes that were deposited on a Kapton substrate by reactive sputtering and patterned by UV lithography. In order to improve the out-of-plane flexibility, the mechanical design is distinguished by a post-buckled flexure that introduces a negative stiffness to compensate the otherwise positive stiffness of the system. The buckling was introduced by a new method, called Package-Induced Preloading (PIP) where the mechanisms are laminated over a package with a geometry extending out-of-plane. The induced buckling resulted in bi-stable and statically balanced mechanisms which demonstrated an enhanced voltage output during a triggered snapping step. A preliminary study shows potential for the statically balanced designs and the PIP method for wind energy harvesting, revealing prospective applications and future improvements for the development of energy harvesters.
AB - There is a high demand for novel flexible micro-devices for energy harvesting from low-frequency and random mechanical sources. The research of new functional designs is required to strategically enhance the performances and to increase the control on mechanical flexibility. In this work we report the fabrication and characterization of bi-stable and statically balanced thin-film piezoelectric transducers based on Aluminum Nitride (AlN). The device consists of a piezoelectric layer sandwiched between two thin Molybdenum electrodes that were deposited on a Kapton substrate by reactive sputtering and patterned by UV lithography. In order to improve the out-of-plane flexibility, the mechanical design is distinguished by a post-buckled flexure that introduces a negative stiffness to compensate the otherwise positive stiffness of the system. The buckling was introduced by a new method, called Package-Induced Preloading (PIP) where the mechanisms are laminated over a package with a geometry extending out-of-plane. The induced buckling resulted in bi-stable and statically balanced mechanisms which demonstrated an enhanced voltage output during a triggered snapping step. A preliminary study shows potential for the statically balanced designs and the PIP method for wind energy harvesting, revealing prospective applications and future improvements for the development of energy harvesters.
KW - Aluminum Nitride (AlN)
KW - Buckling
KW - Compliant micro-mechanisms
KW - Mechanical energy harvesting
KW - Package-induced preloading
KW - Piezoelectric transducers
UR - http://www.scopus.com/inward/record.url?scp=85103116294&partnerID=8YFLogxK
U2 - 10.1016/j.nanoen.2021.105986
DO - 10.1016/j.nanoen.2021.105986
M3 - Article
AN - SCOPUS:85103116294
SN - 2211-2855
VL - 85
JO - Nano Energy
JF - Nano Energy
M1 - 105986
ER -