International Business Machines Corporation

Sensitec Gmbh

Hubert Grimm

Rolf Schaefer

Marcus Breuer

Nikolaus Luckner

Andreas Heinrich Dietzel

Hans-Guenter Kraemer

Jan Marien

Guenther Michaelis

Karl-Heinz Lehnhert

Viktor Spetter

A magnetic field sensor apparatus is provided for measuring one magnetic field vector component H. The apparatus includes at least one anisotropic magneto-resistive resistor device (AMR resistor device) on a chip substrate, where the resistor device includes a plurality of magneto-resistive AMR resistor elements which are connected in series by electrically conductive strips. At least one permanent-magnetic magnetization element with a magnetization axis is assigned to each resistor element in such a way that the resistor element is passed through by an initial magnetization field Hof the magnetization element in the direction of the magnetization axis. A measurement current Iflowing through the resistor element from a contact region between a first conductive strip and the resistor element to a contact region between the resistor element and a second conductive strip has a mean current direction axis at a predefined linearization angle &#x3b1;&#x3e;0&#xb0; and &#x3b1;&#x3c;90&#xb0; relative to the magnetization axis. A highly sensitive magnetic field sensor apparatus can be manufactured economically in large numbers.

Magnetic field sensor device

A high-resolution magnetic encoder system includes a magnetic resistive sensor, a fixed suspension, and a mechanism. The magnetic resistive sensor is mounted to the fixed suspension above a magnetic medium having at least one magnetic track. The fixed suspension is attached to the mechanism, such as a housing, a substrate, and/or an electronic board. The sensor is adapted to perform a relative movement with respect to and in close contact to the surface of the magnetic medium. The magnetic medium may be protected by an overcoat layer. The magnetic resistive sensor may be Giant Magnetic-Resistive (GMR) sensor and/or a Tunneling Magnetic-Resistive Sensor (TMR).

High-resolution magnetic encoder

A magnetic sensor having at least a first and at least a second structure of soft-magnetic material that are spatially separated and define a first gap therebetween. The first and second structure of soft-magnetic material are adapted to form a gap magnetic field pointing in a direction substantially perpendicular to the elongation of the first gap in the vicinity of the first gap in response to an external magnetic field. Additionally, the magnetic sensor comprises at least a first magnetoresistive layered structure that is positioned in the vicinity of the first gap including inside the first gap and that is sensitive to the gap magnetic field.

Magnetic sensor

A system for use when measuring a magnetostriction value of a magnetoresistive element according to one embodiment includes a mechanism for applying a first magnetic field about parallel to a substrate having one or more magnetoresistive elements, and for applying a second magnetic field about perpendicular to the substrate and about parallel to magnetoresistive layers of the elements; and a mechanism for applying a mechanical stress to the substrate during application of the magnetic fields.

Systems for measuring magnetostriction in magnetoresistive elements

A system for use when measuring a magnetostriction value of a magnetoresistive element according to one embodiment includes a mechanism for applying a first magnetic field about parallel to a substrate having one or more magnetoresistive elements, and for applying a second magnetic field about perpendicular to the substrate and about parallel to magnetoresistive layers of the elements; a mechanism for applying a mechanical stress to the substrate during application of the magnetic fields; and a measuring subsystem for measuring a signal from at least one of the magnetoresistive elements, wherein the second magnetic field is a magnetic alternating field, wherein the measuring subsystem is locked to a frequency of the alternating field.

A magnetic encoder system according to one embodiment includes a magnetic sensor mounted on a first substrate above a magnetic medium, the magnetic medium carrying at least one magnetic track, the sensor detecting changes in the magnetic track during a relative movement between the sensor and the magnetic medium. The first substrate is provided with a second substrate rotatably engaging the magnetic medium.

Magnetic Encoder System wherein a first substrate is provided with a second substrate which rotatably engages the magnetic medium

A method for measuring a magnetostriction value of a magnetoresistive element according to one embodiment includes placing a substrate carrying one or more magnetoresistive elements on a fixture; applying a first magnetic field about parallel to the substrate; applying a second magnetic field about perpendicular to the substrate and about parallel to magnetoresistive layers of the one or more elements; measuring a signal from at least one of the one or more elements; applying a mechanical stress to the substrate; and monitoring the signal from the at least one of the one or more elements while changing the first magnetic field.

Methods for measuring magnetostriction in magnetoresistive elements

A system for directly measuring a magnetostriction value of a magnetoresistive element includes a fixture for receiving a substrate carrying one or more magnetoresistive elements. A magnet assembly applies a first magnetic field parallel to the substrate, and a magnetic alternating field perpendicular to the substrate and parallel to magnetoresistive layers of the elements. A stress-inducing mechanism applies a mechanical stress to the substrate, the stress being oriented parallel to the substrate. A measuring subsystem measures a signal from at least one of the magnetoresistive elements.

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Mommenheim, Germany

Hubert Grimm