High-Stability Quartz Resonant Accelerometer With Micro-Leverages

This study proposes a highly stable differential resonant accelerometer that is monolithically micro-machined from a piece of ultrapure, single z-cut crystal quartz. The overall structure of quartz accelerometer is centrally symmetrical, which comprises two double-ended tuning forks (DETFs), two link beams, two micro-leverages, a proof mass, and a quartz frame. Micro-leverages and DETFs are perpendicular to each other and are located around the chip, which maximizes the utilization of the sensor area and is conducive to the miniaturization of the sensor. The effectiveness of the structure was verified by theoretical analysis, simulation, and experiment. The structure with differential arrangement can eliminate common mode disturbances, such as temperature, to improve sensitivity to acceleration. Within the measurement range of ±100 g, the sensor's sensitivity, which is measured by experiments, is 17.72 Hz/g, with a velocity random walk of 0.84 μg/√ Hz and bias instability of 3.05 μg, which is consistent with the theoretical analysis results. [2020-0309]