Low-frequency noise in planar Hall effect bridge sensors
2011 (English)In: Sensors and Actuators A-Physical, ISSN 0924-4247, Vol. 171, no 2, 212-218 p.Article in journal (Refereed) Published
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 400 Hz. 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.
Place, publisher, year, edition, pages
Elsevier, 2011. Vol. 171, no 2, 212-218 p.
Magnetoresistance, Planar Hall effect, Low-frequency noise, Detectivity
Research subject Engineering Science with specialization in Microsystems Technology; Engineering Science with specialization in Solid State Physics
IdentifiersURN: urn:nbn:se:uu:diva-163740DOI: 10.1016/j.sna.2011.09.014ISI: 000297454400022OAI: oai:DiVA.org:uu-163740DiVA: diva2:464746
FunderKnut and Alice Wallenberg FoundationSwedish Research Council