An AlN Micromachined Mass Sensor: Modeling and Characterization

This article presents a mass sensor based on a low-frequency MEMS resonator. Its mechanical structure grants a linear relationship between the measured mass and resonance frequency. The presence of an embedded AlN layer allows for exploiting piezoelectric actuation and sensing and for using a simple and low-cost read-out electronics. In this article, the linear behavior of the sensor is demonstrated by finite-element method (FEM) modal analysis, by developing a simple lumped parameter model and by experimental campaigns. Moreover, in this article, the device performance in terms of piezoelectric transduction is theoretically analyzed and demonstrated using both FEM analysis and experiments, showing that the proposed MEMS device is suitable also for applications in the low-power electronics scenario.