A Sub-Micro-G Resolution Frequency-Modulated Piezoelectric In-Plane Accelerometer

This paper reports on the design, implementations and preliminary characterization of an ultra-sensitive frequency modulated (FM) resonant accelerometer. The accelerometer consists of a pair of piezoelectrically actuated clamped-clamped beam resonators implemented in the device layer of an SOI wafer, and a proof-mass with mechanical coupler and force amplifier defined in both the device and handle layer of an SOI substrate. The device is designed to detect minimum acceleration in the range of 10s of nano-g while having a linear upper range of 25g with 0.5% of scale factor nonlinearity. Fabricated devices measure 660 nano-g/Hz VRW and 2μg BI using discrete electronics with projected bandwidth of 260Hz.