Towards picoTesla Magnetic Field Detection Using a GMR-MEMS Hybrid Device

Author

Guedes, A. ; Jaramillo, G. ; Buffa, C. ; Vigevani, G. ; Cardoso, S. ; Leitão, D.C. ; Freitas, P.P. ; Horsley, D.A.

Author_Institution

Berkeley Sensor & Actuator Center, Univ. of California, Davis, CA, USA

Volume

48

Issue

11

fYear

2012

Firstpage

4115

Lastpage

4118

Abstract

We are developing a novel MEMS-magnetoresistive hybrid device aimed at ultra low magnetic field detection. The hybrid device combines magnetoresistive (MR) sensors and AlN based piezoelectric MEMS resonators. The MR sensor can achieve highly sensitive magnetic field detection but suffers from high magnetic and electrical 1/f noise, limiting its applicability for dc and low-frequency field detection. We overcome this problem by using two piezoelectric cantilevers with integrated magnetic flux concentrators (MFC) to mechanically modulate the external magnetic fields into the high frequency region where the 1/f noise in the MR device vanishes. In this paper we report our fabrication approach and preliminary characterization of the hybrid device.

Keywords

1/f noise; SQUIDs; crystal resonators; giant magnetoresistance; magnetic field effects; magnetic noise; magnetoresistive devices; micromechanical devices; AlN based piezoelectric MEMS resonators; GMR-MEMS hybrid device; MEMS-magnetoresistive hybrid device; MR sensor; dc field detection; electrical 1/f noise; external magnetic fields; highly sensitive magnetic field detection; integrated magnetic flux concentrators; low-frequency field detection; magnetic 1/f noise; magnetoresistive sensors; picotesla magnetic field detection; piezoelectric cantilevers; ultra low magnetic field detection; Amplitude modulation; Frequency modulation; Magnetic devices; Magnetic recording; Micromechanical devices; Noise; Sensitivity; 1/f noise cancelation; Low magnetic field sensing; magnetoresistive sensors; piezoelectric MEMS;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2012.2203297

Filename

6332723