Abstract:
This paper reports on the design and optimization of a 2-axis, single proof mass MEMS capacitive accelerometer, using the Inertial Measurement Unit (IMU) platform of Glob...Show MoreMetadata
Abstract:
This paper reports on the design and optimization of a 2-axis, single proof mass MEMS capacitive accelerometer, using the Inertial Measurement Unit (IMU) platform of GlobalFoundries. The accelerometer consists of a square proof mass suspended using crab leg springs. As dual axis accelerometers are designed to work in both in-plane directions, they are prone to cross-coupling between in-plane acceleration and Z-axis acceleration. This is due to the structural design that makes them sensitive to cross-axis acceleration. Moreover, low stiffness in Z-axis causes the proof-mass to sag due to gravity. In the present paper, we address the cross-axis sensitivity issue in the context of a high-sensitivity, differential capacitive accelerometer in a small footprint of 1.5mm × 1.5 mm, with reduced in-plane cross-axis sensitivity and high frequency separation among the in-plane and Z-axis modes. Simulation results show a differential capacitive sensitivity of 59fF/g (g=9.8 m/s2) can be achieved. The device also has a mode separation of 10 kHz between in-plane and out-of-the plane modes. The average cross-axis sensitivity in XY is 1.33% and the cross-axis sensitivity due to Z-axis acceleration is zero.
Date of Conference: 16-19 October 2016
Date Added to IEEE Xplore: 06 March 2017
ISBN Information:
Electronic ISSN: 1558-3899