Journal article
Low-frequency noise in planar Hall effect bridge sensors
Uppsala University1
MEMS-AppliedSensors Group, MicroElectroMechanical Systems Section, Department of Micro- and Nanotechnology, Technical University of Denmark2
MicroElectroMechanical Systems Section, Department of Micro- and Nanotechnology, Technical University of Denmark3
Department of Micro- and Nanotechnology, Technical University of Denmark4
The low-frequency characteristics of planar Hall effect bridge sensors are investigated as function of the sensor bias current and the applied magnetic field. The noise spectra reveal a Johnson-like spectrum at high frequencies, and a 1/f-like excess noise spectrum at lower frequencies, with a knee frequency of around 400Hz.
The 1/f-like excess noise can be described by the phenomenological Hooge equation with a Hooge parameter of γH=0.016. The detectivity is shown to depend on the total length, width and thickness of the bridge branches. The detectivity is improved by the square root of the length increase. Moreover, the detectivity is shown to depend on the amplitude of the applied magnetic field, revealing a magnetic origin to part of the 1/f noise.
Language: | English |
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Year: | 2011 |
Pages: | 212-218 |
ISSN: | 18733069 and 09244247 |
Types: | Journal article |
DOI: | 10.1016/j.sna.2011.09.014 |
ORCIDs: | Hansen, Mikkel Fougt |