199results about "Galvano-magnetic devices" patented technology

A magnetic element for a high-density memory array includes a resettable layer and a storage layer. The resettable layer has a magnetization that is set in a selected direction by at least one externally generated magnetic field. The storage layer has at least one magnetic easy axis and a magnetization that changes direction based on the spin-transfer effect when a write current passes through the magnetic element. An alternative embodiment of the magnetic element includes an additional multilayer structure formed from a tunneling barrier layer, a pinned magnetic layer and an antiferromagnetic layer that pins the magnetization of the pinned layer in a predetermined direction. Another alternative embodiment of the magnetic element includes an additional multilayer structure that is formed from a tunneling barrier layer and a second resettable layer having a magnetic moment that is different from the magnetic moment of the resettable layer of the basic embodiment.

An integrated sensor has a magnetic field sensing element and first and second relatively high magnetically permeable members forming a gap, wherein the magnetic field element is disposed within the gap. The magnetically permeable members provide an increase in the flux experienced by the magnetic field sensing element in response to a magnetic field. The integrated sensor can be used as a current sensor, a proximity detector, or a magnetic field sensor.

A ferromagnetic thin-film based magnetic field detection system having a substrate supporting a magnetic field sensor in a channel with a first electrical conductor supported on the substrate positioned at least in part along the channel gap and in direct contact with at least some surface of the magnetic field sensor ands a second electrical conductor supported on the substrate positioned at least in part along the channel gap in a region thereof adjacent to, but separated from, the magnetic field sensor.

A device structure and method for forming an interconnect structure in a magnetic random access memory (MRAM) device. In an exemplary embodiment, the method includes defining a magnetic stack layer on a lower metallization level, the magnetic stack layer including a non-ferromagnetic layer disposed between a pair of ferromagnetic layers. A conductive hardmask is defined over the magnetic stack layer, and selected portions of the hardmask and the magnetic stack layer, are then removed, thereby creating an array of magnetic tunnel junction (MTJ) stacks. The MTJ stacks include remaining portions of the magnetic stack layer and the hardmask, wherein the hardmask forms a self aligning contact between the magnetic stack layer and an upper metallization level subsequently formed above the MTJ stacks.

A material stack has an electrical resistance generally the same in the presence of a magnetic field and in the presence of no magnetic field. The electrical resistance of the material stack has a temperature coefficient generally the same as a magnetoresistance element.

Disclosed are a high-sensitivity and high-reliability magnetoresistance effect device (MR device) in which bias point designing is easy, and also a magnetic head, a magnetic head assembly and a magnetic recording / reproducing system incorporating the MR device. In the MR device incorporating a spin valve film, the magnetization direction of the free layer is at a certain angle to the magnetization direction of a second ferromagnetic layer therein when the applied magnetic field is zero. In this, the pinned magnetic layer comprises a pair of ferromagnetic films as antiferromagnetically coupled to each other via a coupling film existing therebetween. The device is provided with a means of keeping the magnetization direction of either one of the pair of ferromagnetic films constituting the pinned magnetic layer, and with a nonmagnetic high-conductivity layer as disposed adjacent to a first ferromagnetic layer on the side opposite to the side on which the first ferromagnetic layer is contacted with a nonmagnetic spacer layer. With that constitution, the device has extremely high sensitivity, and the bias point in the device is well controlled.

A hard bias structure for biasing a free layer in a MR element within a magnetic read head is comprised of a soft magnetic underlayer such as NiFe and a hard bias layer comprised of Co78.6Cr5.2Pt16.2 or Co65Cr15Pt20 that are rigidly exchange coupled to ensure a well aligned longitudinal biasing direction with minimal dispersions. The hard bias structure is formed on a BCC seed layer such as CrTi to improve lattice matching. The hard bias structure may be laminated in which each of the underlayers and hard bias layers has a thickness that is adjusted to optimize the total Hc, Mrt, and S values. The present invention encompasses CIP and CPP spin values, MTJ devices, and multi-layer sensors. A larger process window for fabricating the hard bias structure is realized and lower asymmetry output and NBLW (normalized base line wandering) reject rates during a read operation are achieved.

The apparatus for measurement of a current which is flowing in an axially elongated electrical conductor at a first electrical potential. The apparatus contains at least one associated sensor element associated with the conductor that is electrically isolated from it at a second electrical potential different from the first electrical potential of the electrical conductor, and having magnetoresistive characteristics. The sensor element is intended to form a loop which is magnetically closed around the conductor in the circumferential direction, with the resistance value being tapped off at axially opposite ends. Its magnetoresistive part is preferably composed of a non-metallic powder composite material with a high magnetoresistive effect.

A magnetic field sensor has a plurality of vertical Hall elements arranged in at least a portion of a polygonal shape. The magnetic field sensor includes an electronic circuit to process signals generated by the plurality of vertical Hall elements to identify a direction of a magnetic field. A corresponding method of fabricating the magnetic field sensor is also described.

Provided is a highly-sensitive Hall element capable of eliminating an offset voltage without increasing the chip size. At the four vertices of a square Hall sensing portion, Hall voltage output terminals and control current input terminals are respectively arranged independently from each other. The Hall voltage output terminals all have the same shape. The control current input terminals are arranged on both sides of the Hall voltage output terminals, respectively, to be spaced apart from the Hall voltage output terminals so as to prevent electrical connection to the Hall voltage output terminals, and have the same shape at the four vertices.

A magnetic head having improved self-pinning. The head includes a sensor having an antiparallel (AP) pinned layer structure, where the AP pinned layer structure includes at least two pinned layers having magnetic moments that are self-pinned antiparallel to each other, the pinned layers being separated by an AP coupling layer. A pair of compression layers are positioned towards opposite track edges of the sensor. The compression layers provide compressive stress to the sensor.

A method for testing a TMR element includes a step of measuring a plurality of resistances of the TMR element by feeding a plurality of sense currents with different current values each other through the TMR element, a step of calculating a ratio of change in resistance from the measured plurality of resistances of the TMR element, and a step of evaluating the TMR element using the calculated ratio of change in resistance.

A method and an apparatus of a magnetic field sensor structure are disclosed. The magnetic field sensor structure is formed by a bridge of four magnetoresistors (1–4), wherein each magnetoresistor has a longitudinal direction, and each magnetoresistor (1–4) is polarised by magnets (15–19). Also, each magnet has a main magnetisation field along an axial magnetisation direction, and a magnetic leakage field. The polarisation magnets (15–19) and the magnetoresistors (1–4) are arranged in the form of layers on the same substrate. In one embodiment, the polarisation magnets (15–19) are at the same level as the magnetoresistors (1–4) wherein the polarisation magnets (15–19) have the same main magnetisation direction, which is contained in the plane of the layers. The magnetoresistors have their longitudinal direction parallel with that of the axial direction of the magnets. In one embodiment, two magnetoresistors are arranged in the axial field of magnets and two others are in the magnet leakage field.

An extraordinary magnetoresistance (EMR) sensor has a planar shunt and planar leads formed on top of the sensor and extending downward into the semiconductor active region, resulting. Electrically conductive material, such as Au or AuGe, is first deposited into lithographically defined windows on top of the sensor. After liftoff of the photoresist a rapid thermal annealing process causes the conductive material to diffuse downward into the semiconductor material and make electrical contact with the active region. The outline of the sensor is defined by reactive etching or other suitable etching techniques. Insulating backfilling material such as Al-oxide is deposited to protect the EMR sensor and the edges of the active region. Chemical mechanical polishing of the structure results in a planar sensor that does not have exposed active region edges.