Ultrasensitive Reduced Vanadium Dioxide-Based MEMS Pirani Gauge with Extended Dynamic Range

The paper presents an ultrasensitive vanadium dioxide (VO2)-based MEMS Pirani gauge for vacuum detection of packaged electronic devices. The active element consists of a reduced VO2 formed by reducing the vanadium pentoxide (V2O5) via a vacuum annealing process. The monoclinic phase of VO2 under critical temperature (~ 67 °C) is exploited for the given application. Favorable properties of VO2 include lower thermal conductivity, high resistance, and high-temperature coefficient of resistance, which reflects high sensitivity and extended dynamic range at lower power consumption. Simulations are carried out in COMSOL multiphysics and results show that the presented gauge can be used for vacuum detection from 0.1 to 105 Pa. Moreover, the average overheat temperature is ~  40 °C which follows the safe limit to avoid thermal interaction with onboard electronics.