Energy dissipation mechanisms in lead zirconate titanate thin film transduced micro cantilevers

A high quality factor (Q-factor) is most desirable for resonant mass sensors because their sensitivity greatly depends on the detectable frequency shift after mass adsorption. The authors fabricated lead zirconate titanate (PZT) thin film transduced micro cantilevers and studied the energy dissipation mechanisms to better understand the essential aspects affecting the Q-factor. It was found that energy dissipation induced by the multi-layered device structure and the PZT thin film was noteworthy even under atmospheric pressure conditions. The effects of the PZT film on the energy dissipation became dominant under reduced pressure. Accordingly, the Q-factors of cantilevers without PZT film became larger than those with PZT film when pressure was reduced into the molecular flow region. The single-layered SiO₂ cantilever exhibited the largest intrinsic Q-factor. The electro-mechanical conversion in the PZT film and the thermoelastic damping caused by the property difference between each layer contributed significantly to the energy dissipation.