A novel micro-Fluxgate sensor based on the AMR effect of ferromagnetic film-resistors

Dimitropoulos, PD; Avaritsiotis, JN; Hristoforou, E

dc.contributor.author	Dimitropoulos, PD	en
dc.contributor.author	Avaritsiotis, JN	en
dc.contributor.author	Hristoforou, E	en
dc.date.accessioned	2014-03-01T01:18:33Z
dc.date.available	2014-03-01T01:18:33Z
dc.date.issued	2003	en
dc.identifier.issn	0924-4247	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/15080
dc.subject	AMR sensors	en
dc.subject	Fluxgates	en
dc.subject	Magnetometers	en
dc.subject	MEMS	en
dc.subject	Spin-valves	en
dc.subject.classification	Engineering, Electrical & Electronic	en
dc.subject.classification	Instruments & Instrumentation	en
dc.subject.other	Ferromagnetic materials	en
dc.subject.other	Magnetic anisotropy	en
dc.subject.other	Magnetic films	en
dc.subject.other	Magnetic flux	en
dc.subject.other	Magnetometers	en
dc.subject.other	Magnetoresistance	en
dc.subject.other	Mathematical models	en
dc.subject.other	Spin-valves	en
dc.subject.other	Microscopes	en
dc.title	A novel micro-Fluxgate sensor based on the AMR effect of ferromagnetic film-resistors	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/S0924-4247(03)00378-9	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S0924-4247(03)00378-9	en
heal.language	English	en
heal.publicationDate	2003	en
heal.abstract	A novel magnetic field sensor is presented in this paper. It combines the classical Fluxgate principle with the anisotropic magneto-resistance (AMR) effect exhibited by barber-pole biased AMR film-resistors. It is shown that such film-resistors can be used as Fluxgate magnetic cores, because they exhibit one high-resistivity state and one low-resistivity state depending on the film magnetization polarity. Periodical alteration of the magnetization polarity, forced by an excitation field, makes the film-resistivity become a rectangular function of time, whose duty-cycle is proportional to the measured ambient field intensity. The proposed design helps with the suppression of repeatability and time-drift errors that are common in AMR sensors; the excitation field enhances the spin-alignment along the easy-axis of the film-resistor. The design also provides excellent temperature stability. Moreover, it is shown how a single AMR film-resistor can be employed for simultaneous sensing of two field components (i.e. on a x-y plane); the first component modulates the duty-cycle of the rectangular function (Fluxgate principle) and the latter its amplitude (conventional AMR effect). A complete mathematical modeling of the proposed sensor is presented in this work. The theoretical results have been verified by the use of a Honeywell HMC1021 single-chip sensor. The calibration data fairly agrees with the theory. (C) 2003 Elsevier B.V. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE SA	en
heal.journalName	Sensors and Actuators, A: Physical	en
dc.identifier.doi	10.1016/S0924-4247(03)00378-9	en
dc.identifier.isi	ISI:000186376400005	en
dc.identifier.volume	107	en
dc.identifier.issue	3	en
dc.identifier.spage	238	en
dc.identifier.epage	247	en