Citation
González Castilla, Sheila and Olivares Roza, Jimena and Clement Lorenzo, Marta and Iborra Grau, Enrique and Sangrador García, Jesús and Malo Gomez, Javier and Izpura Torres, José Ignacio
(2008).
Electrical detection of the mechanical resonances in AlN-actuated microbridges for mass sensing applications.
"Applied Physics Letters", v. 92
(n. 18);
pp. 183506-1.
ISSN 0003-6951.
https://doi.org/10.1063/1.2924284.
Abstract
We report the fabrication and frequency characterization of mechanical resonators piezoelectrically actuated with aluminum nitride films. The resonators consist of a freestanding unimorph structure made up of a metal/AlN/metal piezoelectric stack and a Si3N4 supporting layer. We show that the electrical impedance of the one-port device can be used to assess the vibrational behavior of the resonators, provided that the modes do not exhibit specific symmetries, for which the impedance variations cancel. Frequency shifts arise when loading the resonators with small masses. As gravimetric sensors, the microbridges exhibit mass sensitivities of 0.18 fg/Hz for vibrational modes around 2 MHz.
