High Quality Factor Silicon Cantilever Driven by PZT Actuator for Resonant Based Mass Detection

TL;DR

This paper presents a PZT-actuated silicon cantilever with a high Q-factor for ultra-sensitive mass detection, achieved by separating the PZT actuator from the resonant structure to reduce energy loss.

Contribution

The study introduces a novel PZT-actuated silicon cantilever design with significantly improved Q-factor by minimizing energy dissipation, enabling enhanced mass sensing sensitivity.

Findings

Q-factor up to 1113 at atmospheric pressure

Q-factor up to 7279 under reduced pressure

Optimized node-point actuation suppresses energy dissipation

Abstract

A high quality factor (Q-factor) piezoelectric lead zirconat titanate (PZT) actuated single crystal silicon cantilever was proposed in this paper for resonant based ultra-sensitive mass detection. Energy dissipation from intrinsic mechanical loss of the PZT film was successfully compressed by separating the PZT actuator from resonant structure. Excellent Q-factor, which is several times larger than conventional PZT cantilever, was achieved under both atmospheric pressure and reduced pressures. For a 30 micrometer-wide 100 micrometer-long cantilever, Q-factor was measured as high as 1113 and 7279 under the pressure of 101.2 KPa and 35 Pa, respectively. Moreover, it was found that high-mode vibration can be realized by the cantilever for the pursuit of great Q-factor, while support loss became significant because of the increased vibration amplitude at the actuation point. An optimized structure using node-point actuation was suggested then to suppress corresponding energy dissipation.