Self biased multilayer magnetoresistance sensor

US5635835A · kind A · utility

Assignee

• COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES · FR

Inventors

• Jean Mouchot · Grenoble, FR
• Bernard Dieny · Le Pont-de-Claix, FR

Key dates

• Filing date: Jul 10, 1995
• Grant date: Jun 3, 1997
• Expiry date: Jul 10, 2015

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10N50/10
• WIPO field: Micro-structural and nano-technology
• WIPO sector: Chemistry

Abstract

A self-bias sensor including a current source, a resistance measuring device and a sensor element sensitive to a magnetic field to be measured. The sensor element receives from the current source a current which creates a self-biasing field. The sensor element includes a first ferromagnetic layer having a magnetization direction which is sensitive to the magnetic field and when not subject to the magnetic field, and is oriented by the self-biasing field in a direction perpendicular to a longitudinal direction of the sensor element; a second ferromagnetic layer disposed between a first and second conductive layer, where the second ferromagnetic layer has a magnetization which is blocked and directed in the longitudinal direction; and a third ferromagnetic layer which is disposed on the second conductive layer and has a magnetization direction which is sensitive to the magnetic field and, when not subject to the magnetic field, is oriented by the self-biasing field in a second direction perpendicular to the longitudinal direction and substantially of an opposite sense to the magnetization of the first ferromagnetic layer.