Test and calibration of MEMS convective accelerometers with a fully electrical setup

MEMS devices are expected to be used in a growing number of high-volume and low-cost applications. However because they typically requires the application of physical test stimuli to verify their specifications, test and calibration costs are actually a bottleneck to reduce the overall production cost of MEMS sensor. This paper presents an alternative electrical-only solution for testing and calibrating the sensitivity of MEMS convective accelerometers. It is based on simple impedance measurements performed both at ambient temperature and under nominal biasing conditions. The method is evaluated through Monte-Carlo simulations considering typical process fluctuations and mismatch. Results show the potentialities of the technique that permits to reduce the dispersion of sensitivity by a factor higher than 11 after calibration. As a consequence, a production yield of more than 99.8% can be expected for low-cost products using only electrical measurements for the calibration scheme.