Passive Method for Reducing Temperature Sensitivity of a Microelectromechanical Seismic Accelerometer for Marsquake Monitoring Below 1 Nano- g

Abstract

The passive technology described in this paper is important for reducing the thermoelastic response of silicon-based high-precision accelerometers and gravimeters. This study uses the angular strain induced by mismatched coefficients of thermal expansion to passively compensate for the sag displacement in Si-based spring-mass systems in environments with fluctuating temperature. The hundredfold reduction in temperature sensitivity allows a top acceleration sensitivity of less than 10${}^{\ensuremath{-}9}$ $g$. Such a temperature-compensated seismic accelerometer has already been used as a science payload of the InSight Mars lander, which touched down in November 2018, for marsquake monitoring.