Thermal Characterization of Scale-Factor and Zero-Rate Offset in Near-Navigation-Grade Nems-Based Gyroscopes

This work presents further advancements on miniaturized gyroscopes based on NEMS sensing, towards navigation grade applications, discussing in particular the thermal characterization of scale-factor (SF) and zero-rate-offset (ZRO). The gyroscope design, fitting in 1.3 mm(2) only, maximizes the electromechanical transduction with resistive NEMS-gauge sensing. In terms of input-referred rate, this approach reduces both noise and drift effects originating after the conversion from rate into electrical signals. Besides reaching navigation-grade performance for noise (0.005 degrees/vhr) and bias instability (0.015 degrees/hr), the gyroscope shows native offset drift of 275 mu dps/K only (average of absolute values over 6 samples), an unrivaled result for devices of this size, package cost and consumption. After linear calibration, offsets remain within +/- 5 mdps (5 degrees C-85 degrees C range) and scale factor drifts are limited to +/- 1500 ppm.