Development of magnetoresistive sensors based on planar Hall effect for applications to microcompass

• Published in: Sensors and actuators. A, Physical Vol. 81; no. 1; pp. 324 - 327
• Main Authors: Montaigne, François, Schuhl, Alain, Van Dau, Frédéric Nguyen, Encinas, Armando
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Lausanne Elsevier B.V 01.04.2000; Elsevier Science
• Subjects: Applied sciences; Electronics; Exact sciences and technology; General equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Magnetic components, instruments and techniques; Magnetic devices; Magnetic sensor; Magnetic thin film devices: magnetic heads (magnetoresistive, inductive, etc.); domain-motion devices, etc; Magnetoresistance; Physics; Planar Hall effect; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Planar Hall effect; Magnetoresistance; Magnetic sensor; Magnetic field measurement; Permalloy; Magnetization; Magnetic sensors; Magnetic anisotropy; Hall effect; Experimental study; Switching system; Compasses; Planar configuration
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/S0924-4247(99)00102-8

We present here a new magnetoresistive sensor based on planar Hall effect for detection of low magnetic fields (10 nT) in the 1–1000 Hz frequency range. These sensors are suitable for low-cost fabrication. The growth of a Permalloy (FeNi) active layer by conventional sputtering on misoriented silicon substrates leads to a well controlled in-plane uniaxial magnetic anisotropy. Moreover, a magnetisation switching system allows to remove any offset of the measure. The association of two orthogonal sensors will give a micro-compass with an angular resolution, below 0.5°, limited by the precision of assembling, with a device size of the order of 1 mm 2.