Koninklijke Philips Corporation N.V.

U.S. Philips Corporation

Derk Jan Adelerhof

Reinder Coehoorn

Kars-Michiel Hubert Lenssen

Joannes Baptist Adrianus Dionisius Van Zon

Ronald Dekker

Hans Willem Van Kesteren

Henricus G R Maas

Antonius Emilius Theodorus Kuiper

Jacques C S Kools

Gerardus Henricus Johannes Somers

A method of manufacturing a magnetic tunnel junction device, in which a stack () comprising two magnetic layers () and a barrier layer () extending in between is formed. One of the magnetic layers is structured by means of etching, in which, during etching, a part of this layer is made thinner by removing material until a rest layer () remains. This rest layer is passivated by chemical conversion. In the relevant method, it is prevented that the magnetic layer which is not to be structured is detrimentally influenced during structuring of the other magnetic layer.

Method of manufacturing a magnetic tunnel junction device

A magnetoresistive angular sensor ( ) is provided which determines a magnetic field direction. A high angular accuracy over a wide range of magnetic field strengths is obtained. The magnetoresistive angular sensor comprises a main sensing element ( ) which is electrically connected to a first correction sensing element ( ) with a first reference magnetization axis ( ) and a second correction sensing element ( ) with a second reference magnetization axis ( ), the first ( ) and the second ( ) reference magnetization axes making correction angles &THgr; between 5&deg; and 85&deg; of opposite sign with the main reference axis ( ).

Magnetoresistive angle sensor having several sensing elements

A thin-film magnetic head has a semiconductor substrate in which there is an integrated circuit, and on which a magnetic layer structure is arranged. During manufacturing the integrated circuit is formed on one side of the semiconductor substrate, and that side of the semiconductor substrate is then secured to a carrier body by a securing layer. The substrate may then be ground or etched to a thickness less than 35&mgr;m before forming the magnetic layer structure on the opposite side. Securing to the carrier body prevents deformation of the layer structure during manufacturing, so that the resulting head has reproducible properties. Preferably a support body is secured over the layer structure. The head face is then formed such that the layer structure and the support and carrier bodies terminate in it.

Magnetic head with integrated circuit on a rigid body

Magnetoresistive sensor ( ) for measuring relative displacements of construction parts ( ). A magnetoresistive element ( ) is formed on a surface ( ) of a substrate ( ). A magnet system ( ) generates a magnetic field ( ) having a component ( ) directed parallel to the substrate surface at the area of the magnetoresistive element. Upon the relative displacement of the construction parts, this field component extends at different angles &agr; to the magnetoresistive element and is so large that the magnetoresistive element is always magnetically saturated during the displacement. Upon a relative displacement of the construction parts, the magnetoresistive element describes a path ( ) with respect to the magnet system. The sensor is suitable for measuring rotations through angles up to 360&deg; and for measuring large translations.

Magnetoresistive sensor for measuring relative displacement of construction parts

A magnetic position detector includes a soft magnetic target wheel, a magnetic sensor and a permanent magnet. The invention includes magnetoresistive sensors in several geometrical configurations of the target wheel, the sensor and the magnet. All configurations result in a big change of direction of the magnetic field at the location of the sensor as a result of a rotation of the target wheel. The configurations have in common that the direction of the magnetic field at the location of the sensor, as generated by the permanent magnet, is predominantly in the plane of the sensor surface, both when the sensor is next to a slot and next to a tooth of the target wheel, the surface of the sensor being substantially normal to the direction of movement of the target wheel.

Magnetic positioning detector using field direction as primary detecting means

A novel magnetic data storage system and a sensing system of magnetic characteristics are disclosed; the systems have a magnetization direction that is irreversible in an external magnetic field. A method of manufacturing, a method of resetting or changing or repairing and a method of operating such systems are also disclosed. The systems can include a set of magnetic devices in a balancing configuration; essentially each of said devices comprises a structure of layers including at least a first ferromagnetic layer and a second ferromagnetic layer with at least a separation layer of a non-magnetic material there between, said structure having at least a magneto resistance effect. The magnetization direction of the first ferromagnetic layer of at least one of said devices is irreversible in an external magnetic field higher than about 35 kA/m.

Magnetic systems with irreversible characteristics and a method of manufacturing and repairing and operating such systems

A thin-film magnetic read head device comprises an end face extending in a first direction, in which a magnetic information carrier is movable with respect to the magnetic head device, and in a second direction, perpendicular to said first direction. The magnetic head device further comprises a multilayer structure with at least two soft-magnetic layers separated by a magnetic insulation layer and with at least one exchange biasing layer, which multilayer structure extends in the second direction and in a third direction, perpendicular to the first and the second direction, and forms at least one flux path in the first and the third direction. The exchange coupling between one of the soft-magnetic layers and the exchange biasing layer is at least partly reduced locally, i.e. interrupted or at least substantially reduced, in at least the second direction, while the exchange biasing layer extends uninterruptedly in the region of said reductions.

Thin-film magnetic read head with locally reduced exchange coupling

A thin film shielded magnetic read head device comprises an end face extending in a first direction, in which a magnetic information carrier is movable with respect to the magnetic head device, and in a second direction, perpendicular to said first direction. The magnetic head device further comprises shield forming flux guiding elements for magnetic cooperation with the information carrier, which elements extend in the second direction and in a third direction, perpendicular to the first and the second direction. A number of magnetoresistive elements each having a spin tunnel junction structure is provided, which number of magnetoresistive elements corresponds to with the number of magnetic channels of the magnetic head device. One of said shields forms a common contact lead for the current through said magnetoresistive elements. Thin film magnetic read head device is applied in a system for reading information from a magnetic information carrier.

Growing community of inventors

Eindhoven, Netherlands

Derk Jan Adelerhof