Paper Info
Title
A CMOS-MEMS BEOL 2-axis Lorentz-Force Magnetometer with Device-Level Offset Cancellation.
Abstract
Lorentz-force Microelectromechanical Systems (MEMS) magnetometers have been proposed as a replacement for magnetometers currently used in consumer electronics market. Being MEMS devices, they can be manufactured in the same die as accelerometers and gyroscopes, greatly reducing current solutions volume and costs. However, they still present low sensitivities and large offsets that hinder their performance. In this article, a 2-axis out-of-plane, lateral field sensing, CMOS-MEMS magnetometer designed using the Back-End-Of-Line (BEOL) metal and oxide layers of a standard CMOS (Complementary Metal-Oxide-Semiconductor) process is proposed. As a result, its integration in the same die area, side-by-side, not only with other MEMS devices, but with the readout electronics is possible. A shielding structure is proposed that cancels out the offset frequently reported in this kind of sensors. Full-wafer device characterization has been performed, which provides valuable information on device yield and performance. The proposed device has a minimum yield of 85.7% with a good uniformity of the resonance frequency fr over bar =56.8 kHz, sigma fr=5.1 kHz and quality factor Q over bar =7.3, sigma Q=1.6 at ambient pressure. Device sensitivity to magnetic field is 37.6fA center dot mu T-1 at P=1130 Pa when driven with I=1mApp.
Year
DOI
Venue
2020
10.3390/s20205899
SENSORS
Keywords
DocType
Volume
MEMS,magnetic sensor,magnetometer,Lorentz-force,offset suppression,micromachined Resonator,micromechanical oscillator
Journal
20
Issue
ISSN
Citations 
20
1424-8220
0
PageRank 
References 
Authors
0.34
0
4
Name
Order
Citations
PageRank
Josep Maria Sánchez-Chiva100.34
Juan Valle200.34
Daniel Fernández3276.82
Jordi Madrenas415027.87