Abstract: Magnetoresistive (MR) elements are disclosed that include pinned layers having canted magnetic moments. An MR element of the invention includes a first pinning layer, a first pinned layer, a first spacer/barrier layer, a free layer, a second spacer/barrier layer, a second pinned layer, and a second pinning layer. The first pinned layer has a canted magnetic moment. By having a canted magnetic moment, the first pinned layer acts as a bias layer to bias the free layer, and acts as a reference layer to enhance the MR signal in the MR element.

Abstract: Improved sensitivity GMR sensors useful for thin film magnetic read heads are disclosed. Spin transfer induced destabilization of the magnetic free layer is suppressed through the application of Tb containing alloys in the free layer. Sense currents can be increased by a factor of five in comparison to prior art designs without an increase in spin transfer induced noise.

Abstract: A CPP-GMR spin value sensor structure with an improved MR ratio and increased resistance is disclosed. All layers except certain pinned layers, copper spacers, and a Ta capping layer are oxygen doped by adding a partial O2 pressure to the Ar sputtering gas during deposition. Oxygen doped CoFe free and pinned layers are made slightly thicker to offset a small decrease in magnetic moment caused by the oxygen dopant. Incorporating oxygen in the MnPt AFM layer enhances the exchange bias strength. An insertion layer such as a nano-oxide layer is included in one or more of the free, pinned, and spacer layers to increase interfacial scattering. The thickness of all layers except the copper spacer may be increased to enhance bulk scattering. A CPP-GMR single or dual spin valve of the present invention has up to a threefold increase in resistance and a 2 to 3% increase in MR ratio.

Abstract: A method of manufacturing a spin valve film, produces a large read out signal. After a completion of a film making process for forming a previous film of two films to be formed successively, but before an initiation of a film making process for forming a succeeding film of the two films, a step of decreasing an anisotropic magnetic field of the spin valve film is introduced by interrupting a film making process. This step may be performed by keeping a substrate within a sputtering vacuum chamber. The interruption can be shortened by exposing the substrate to a plasma, transferring the substrate in a separate vacuum chamber is lower or whose H2O or O2 concentration is higher than that in the sputtering vacuum chamber, conducting a surface treatment with a gas containing H2O or O2, or flowing a process gas.

Abstract: There is disclosed a magnetic recording medium in which a seed layer, under layer, intermediate layer, first magnetic layer, nonmagnetic layer, second magnetic layer, protective layer, and lubricant layer are successively laminated on a glass substrate, the nonmagnetic layer is constituted of an alloy containing Cr and C, and the magnetic layer is constituted of an alloy containing Co and Pt. The under layer includes at least the seed layer for finely dividing the crystal particles of the magnetic layer, the seed layer includes at least two or more layers of nonmagnetic films, and the intermediate layer formed of the material different from that of the nonmagnetic film is interposed between the nonmagnetic films. In measurement of the thermal stability of the magnetic recording medium, a head is used, the head includes a read/write element, and a write track width is twice or more as large as a read track width in the head.

Abstract: A magnetoresistance effect element having a free magnetic layer is provided. The free magnetic layer is formed in a laminate including a fixed magnetization layer having a fixed magnetization direction, a non-magnetic layer formed on the fixed magnetization layer, a first ferromagnetic layer, a non-magnetic metallic layer formed on the first ferromagnetic layer, and a second ferromagnetic layer formed on the non-magnetic metallic layer. The free magnetic layer includes magnetic recording regions, and in each region, the first ferromagnetic layer and the second ferromagnetic layer are coupled such that their magnetization directions are anti-parallel with each other, and one of the magnetic recording regions is opposite to the fixed magnetization layer with the non-magnetic layer therebetween.

Abstract: The invention provides a magnetic recording and reproducing apparatus having magnetic field applying unit applying a magnetic field to a magnetoresistive element to correct a misaligned magnetization direction of the magnetoresistive element. The magnetic field applying unit can be used to correct a misaligned magnetization direction of a free layer of a giant magnetoresistive element. A magnetic field applying unit controller controls the magnetic field applying unit to adjust a magnetization direction and intensity of a magnetic field of the giant magnetoresistive element. The magnetic field applying unit controller can control the magnetic field applying unit to apply a magnetic field only during a data reading time, and to increase the intensity of the application magnetic field during a data re-reading time. The magnetic field applying unit is mounted, corresponding to a head on a suspension that supports a head slider, on a surface of the suspension opposite to the surface on which the head is mounted.

Abstract: A magnetoresistive sensor having a novel laminated hard bias structure that possesses exceptional magnetic performance characteristics when deposited over a crystalline structure such as in a partial mill sensor design in which a portion of a sensor stack extends beyond the active area of the sensor. The hard bias structure may include a seed layer comprising a layer of Si sandwiched between layers of CrMo. The hard bias structure, which can be formed over the seed layer structure, includes layers of CoPt separated a layer of CrMo.

Abstract: The magnetoresistance effect type read-head is capable of stably applying bias magnetic fields of hard films to a read-element, stabilizing characteristics of the read-head and improving quality thereof. The magnetoresistance effect type read-head comprises: the read-element; a couple of the hard films sandwiching the read-element, the hard films applying bias magnetic fields to the read-element; and a soft magnetic film being provided on the height direction side, the soft magnetic film connecting an end section of one of the hard films, which is located on the far side with respect to the read-element, to an end section of the other hard film, which is located on the opposite far side with respect to the read-element, so as to circulate magnetic fluxes of the hard films via the soft magnetic film.

Abstract: As track density requirements for disk drives have grown more aggressive, GMR devices have been pushed to narrower track widths to match the track pitch of the drive width. Narrower track widths degrade stability and can cause amplitude loss and side reading. This problem has been overcome by placing an additional layer of soft magnetic material on the conductive layer. The added layer prevents flux leakage into the gap region. A non-magnetic layer must be included to prevent exchange coupling to nearby magnetic layers. In at least one embodiment the conductive leads are used to accomplish this. A process for manufacturing the device is also described.

Abstract: A current perpendicular to plane (CPP) sensor having FeN in their free and pinned layers. A tunnel junction sensor (TMR) according to the present invention can have a MgO barrier layer, and a CPP GMR sensor according to the present invention can have a Cr spacer layer.

Abstract: A magnetoresistive device comprises: a first shield layer and a second shield layer disposed with a space from each other in the direction of thickness; an MR element disposed between the first and second shield layers; and a layered structure disposed between the first and second shield layers on both sides of the MR element. The layered structure includes an insulating layer and bias field applying layers. The second shield layer has a surface facing toward the first shield layer. This surface includes a first portion touching the top surface of the MR element and second portions located on both sides of the MR element, the sides being opposed to each other in the direction of track width. A difference in level is created between the first and second portions such that the second portions are closer to the first shield layer than the first portion.

Abstract: A current perpendicular to plane (CPP) magnetoresistive sensor having an in-stack bias structure that is pinned by an AFM layer located behind the back edge (stripe height) of the sensor stack. A magnetic coupling layer is exchange coupled to the in-stack bias structure and extends beyond the back edge of the sensor stack where it is pinned by the AFM layer. The magnetic coupling layer may be either directly exchange coupled with the AFM layer or exchange coupled with an intermediate magnetic layer that is itself exchange coupled with the AFM layer. The AFM layer is located entirely beyond the stripe height of the sensor stack and between top and bottom elevations as defined by the top and bottom of the sensor stack. In this way, the AFM can pin the biasing structure without consuming any gap budget.

Abstract: In a CPP magnetic head a free magnetic layer and a magnetic biasing layer are disposed within a central layer stack. To pin the magnetization of the bias layer, an antiferromagnetic (AFM) layer is fabricated on the sides of the central stack. The AFM layer may be comprised of an electrically non-conductive AFM material such as NiO, or, where the AFM material is electrically conductive, such as PtMn or IrMn, a layer of electrical insulation is deposited to prevent the sense current from flowing through the outwardly disposed AFM layer. Portions of the bias layer are deposited upon the outwardly disposed AFM layer, such that the magnetization of the outwardly disposed portions of the bias layer are pinned by the AFM layer, which creates an effective pinning of the central portions of the bias layer. This then provides an effective biasing of the magnetization of the free magnetic layer.

Abstract: Patterned, longitudinally and transversely antiferromagnetically exchange biased GMR sensors are provided which have narrow effective trackwidths and reduced side reading. The exchange biasing significantly reduces signals produced by the portion of the ferromagnetic free layer that is underneath the conducting leads while still providing a strong pinning field to maintain sensor stability. In the case of the transversely biased sensor, the magnetization of the free and biasing layers in the same direction as the pinned layer simplifies the fabrication process and permits the formation of thinner leads by eliminating the necessity for current shunting.

Abstract: A magnetic head with improved hard magnet properties includes a sensor stack structure and a multi-layered seed layer structure formed over crystalline materials of the sensor stack structure. The multi-layered structure has a first layer including chromium-molybdenum (CrMo); a second layer including nitrogenated nickel-tantalum (NiTa+N); and a third layer including chromium-molybdenum (CrMo). A hard bias layer formed over the multi-layered structure is preferably cobalt-platinum-chromium (CoPtCr). Methods of making the magnetic head are also described.

Abstract: A magnetoresistive sensor having an in stack bias structure for biasing the magnetic moment of the free layer. The in stack bias structure includes a magnetic bias layer that may include a layer of NiFe and a layer of CoFe. A layer of antiferromagnetic material (AFM layer) is exchange coupled with the bias layer. Preferably, the NiFe layer of the bias layer is located adjacent to the AFM layer. A non-magnetic spacer layer is sandwiched between the free layer and the bias layer. The spacer layer comprises NiFeCr and is of such a thickness that magnetostatic coupling between the free layer and the bias layer across the spacer layer biases the magnetic moment of the free layer in a direction antiparallel to the magnetic moment of the bias layer. The NiFeCr promotes a desired crystalline growth in the bias layer that causes excellent exchange coupling between the bias layer and the AFM layer.

Abstract: A magnetic head having an in-stack bias structure and a free layer structure. The in-stack bias structure includes an antiferromagnetic layer, and first through fourth antiparallel (AP) pinned bias layers separated by three AP coupling layers. A first spacer layer is positioned above the fourth bias layer of the bias structure. A free layer is positioned above the first spacer layer. The fourth bias layer magnetostatically stabilizes the free layer.

Abstract: A magnetic detecting element, which can suppress change in output asymmetry even if the magnetization direction of a pinned magnetic layer is changed 180°, is provided. The magnetic-film-thickness of a second free magnetic layer is increased so as to be greater than that of a first free magnetic layer and offset the torque applied to the second free magnetic layer with that applied to the first free magnetic layer when the sensing current magnetic field occurs. Thus, change in the magnetization direction of the free magnetic layer before and after a sensing current is applied in the magnetic detecting element can be suppressed. The orthogonal state between the free magnetic layer and the pinned magnetic layer is maintained even when a sensing current in the same direction as that before the occurrence is applied in the magnetic detecting element wherein pin inversion occurred, and the output asymmetry is maintained suitably.

Abstract: Two embodiments of a GMR sensor of the bottom spin valve (BSV) spin filter spin valve (SFSV) type are provided together with methods for their fabrication. In each embodiment the sensor includes an in-situ naturally oxidized specularly reflecting layer (NOL) which is a more uniform and dense layer than such layers formed by high temperature annealing or reactive-ion etching. In one embodiment, the sensor has an ultra thin composite free layer and a high-conductance layer (HCL), providing high output and low coercivity. In a second embodiment, along with the same NOL, the sensor has a laminated free layer which includes a non-magnetic conductive layer, which also provides high output and low coercivity. The sensors are capable of reading densities exceeding 60 Gb/in2.

Abstract: An improved formulation for free layers in MTJ sensors is disclosed. Optimized results of the prior art suggest free layer iron concentrations less than 20 atomic % give the best performance. The present invention discloses improved TMR ratio, Hce, and ? performance for high free layer iron concentrations between about 70 and 91.5 atomic %, when compared to the prior art.

Abstract: The conventional free layer in a CPP GMR read head has been replaced by a tri-layer laminate comprising Co rich CoFe, moderately Fe rich NiFe, and heavily Fe rich NiFe. The result is an improved device that has a higher MR ratio than prior art devices, while still maintaining free layer softness and acceptable magnetostriction. A process for manufacturing the device is also described.

Abstract: A ferromagnetic thin-film based magnetic device with internal film coupling compensation including a nonmagnetic material intermediate layer with an initial thin-film of an anisotropic ferromagnetic material on one side. A compensation thin-film of an anisotropic ferromagnetic material is provided on the opposite side with an antiparallel coupling layer thereon and a subsequent thin-film of an anisotropic ferromagnetic material on the antiparallel coupling layer with the compensation thin-film being less thick than the subsequent thin-film. A antiferromagnetic layer can be supported by the layers on either side of the intermediate layer.

Abstract: By using a free layer that includes a NiFe layer containing between 65 and 72 atomic percent iron, an improved CPP GMR device has been created. The resulting structure yields a higher CPP GMR ratio than prior art devices, while maintaining free layer softness and acceptable magnetostriction. A process for manufacturing the device is also described.

Abstract: A method to fabricate a tunneling magnetoresistive (TMR) read transducer is disclosed. An insulative layer is deposited on a wafer substrate, and a bottom lead is deposited over the insulative layer. A laminated TMR layer, having a plurality of laminates, is deposited over the bottom lead. A TMR sensor having a stripe height is defined in the TMR layer, and a parallel resistor and first and second shunt resistors are also defined in the TMR layer. A top lead is deposited over the TMR sensor. The parallel resistor is electrically connected to the bottom lead and to the top lead. The first shunt resistor is electrically connected to the bottom lead and the wafer substrate, and the second shunt resistor is electrically connected to the top lead and the wafer substrate.

Abstract: A magnetoresistive sensor and method for forming the magnetoresistive sensor. The magnetoresistive sensor includes a first layer and an antiparallel free layer disposed on the first layer. The antiparallel free layer includes a first free layer disposed on the first layer and a first ferromagnetic coupling free layer disposed on the first free layer. The first ferromagnetic coupling layer is configured to provide increased coupling between the first free layer and an antiferromagnetic coupling layer. The antiparallel free layer also includes the antiferromagnetic coupling layer disposed on the first ferromagnetic coupling free layer, a second ferromagnetic coupling free layer disposed on the antiferromagnetic coupling layer, and a second free layer disposed on the second ferromagnetic coupling free layer. The second ferromagnetic coupling layer is configured to provide increased coupling between the second free layer and the antiferromagnetic coupling layer.

Abstract: A magnetoresistive sensor having magnetically anisotropic bias layers for biasing the free layer of the sensor. The sensor includes a sensor stack with a pinned layer structure and a free layer structure and having first and second sides. Hard bias structures for biasing the magnetization of the free layer are formed at either side of the sensor stack, and each of the hard bias structure includes a hard magnetic layer that has a magnetic anisotropy to enhance the stability of the biasing. The hard bias layer is formed on a buffer layer and a seed layer, the seed layer being sandwiched between the buffer layer and the hard bias layer. The buffer layer has an anisotropic surface texture that promotes the magnetic anisotropy in the hard bias layer. The buffer layer can be CrMo or Ru or can be a bi-layer including a layer of CrMo with a layer of Ru over the CrMo. The seed layer can be constructed of a material having a BCC structure and is preferably constructed of CrMo.

Abstract: In a method of fabricating a giant magnetoresistive (GMR) device a plurality of magnetoresistive device layers is deposited on a first silicon nitride layer formed on a silicon oxide layer. An etch stop is formed on the magnetoresistive device layers, and a second layer of silicon nitride is formed on the etch stop. The magnetoresistive device layers are patterned to define a plurality of magnetic bits having sidewalls. The second silicon nitride layer is patterned to define electrical contact portions on the etch stop in each magnetic bit. The sidewalls of the magnetic bits are covered with a photoresist layer. A reactive ion etch (RIE) process is used to etch into the first silicon nitride and silicon oxide layers to expose electrical contacts. The photoresist layer and silicon nitride layers protect the magnetoresistive layers from exposure to oxygen during the etching into the silicon oxide layer.

Abstract: A magnetic recording element includes a fixed layer having first and second surfacesm, a recording layer having third and fourth surfaces and being essentially made of a ferromagnetic material having first and second atomic potentials for the majority-spin band electrons and the minority-spin band electrons, a spacer layer being arranged between the fixed and recording layers and being in contact with the second and third surfaces, a cap layer having fifth and sixth surfaces, being essentially made of a nonmagnetic material having a third atomic potential less than an intermediate value between the first and second atomic potentials, and having a thickness of not more than 3 nm, the fifth surface being in contact with the fourth surface, and a reflecting layer being in contact with the sixth surface and being essentially made of a nonmagnetic material having a forth atomic potential different from the third atomic potential.

Abstract: A magnetic head includes first and second shield layers and a read sensor formed between and in electrical contact with the first and second shield layers. The read sensor includes a free layer structure; an antiparallel (AP) self-pinned structure which includes a first AP self-pinned layer, a second AP self-pinned layer, and an AP coupling layer formed between the first and the second AP self-pinned layers; and a non-magnetic spacer layer formed between the free layer structure and the AP self-pinned structure. The first AP self-pinned layer is formed in both a central region of the read sensor and in side regions adjacent the central region. Since thermal stability of the first AP self-pinned layer is proportional to its volume, extending the first AP self-pinned layer in the side regions improves the thermal stability to reduce the likelihood of amplitude flip in the self-pinned sensor.

Abstract: A TMR read head with improved voltage breakdown is formed by laying down the AP1 layer as two or more layers. Each AP1 sub-layer is exposed to a low energy plasma for a short time before the next layer is deposited. This results in a smooth surface, onto which to deposit the tunneling barrier layer, with no disruption of the surface crystal structure of the completed AP1 layer.

Abstract: The invention provides a giant magneto-resistive effect device having a CPP structure comprising a spacer layer, and a fixed magnetization layer and a free layer stacked one upon another with said spacer layer interposed between them, wherein the free layer functions such that its magnetization direction changes depending on an external magnetic field, and the spacer layer comprises a first nonmagnetic metal layer and a second nonmagnetic metal layer, each formed of a nonmagnetic metal material, and a semiconductor oxide layer interposed between them, wherein the semiconductor oxide layer forming a part of the spacer layer comprises zinc oxide as a main ingredient, wherein the main ingredient zinc oxide contains at least one selected from among oxides containing a trivalent cation of Al2O3, Ga2O3, In2O3, and B2O3, and a tetravalent cation of TiO2.

Abstract: A current-perpendicular-to-the-plane (CPP) magnetoresistive (MR) sensor has an improved free layer structure that includes a first ferromagnetic interface layer on the sensor's nonmagnetic spacer layer, a first electrically conductive interlayer on the first interface layer, a central ferromagnetic NiFe alloy free layer on the first interlayer, a second electrically conductive interlayer on the central free layer, and a second ferromagnetic interface layer on the second interlayer. The first ferromagnetic interface layer, central ferromagnetic free layer, and second ferromagnetic interface layer are ferromagnetically coupled together across the electrically conductive interlayers so their magnetization directions remain parallel. The free layer structure may be used in single or dual CPP sensors and in spin-valve or tunneling MR sensors.

Abstract: A magnetoresistive read head is capable of reading cross-track magnetizations in a magnetic recording disk drive that has the magnetized regions or magnetizations in the magnetic recording layer of the disk oriented in the cross-track direction. The magnetic recording disk has the magnetizations in the concentric data tracks oriented in the radial or cross-track direction. The read head has its free-layer magnetization direction perpendicular to the disk surface and its pinned-layer magnetization direction parallel to the disk surface and orthogonal to the free-layer magnetization direction. The read head may have magnetic side shields spaced from it in the cross-track direction to prevent magnetic flux from adjacent data tracks from reaching the read head.

Abstract: A dual current-perpendicular-to-the-plane (CPP) magnetoresistive sensor has a free ferromagnetic layer formed of a Heusler alloy and each of the pinned ferromagnetic layers formed of a ferromagnetic material other than a Heusler alloy, like a conventional CoFe or NiFe material. The Heusler alloy material in the free layer may be a known Heusler alloy material or an alloy with a composition substantially the same as that of a known Heusler alloy, and which results in high magnetoresistance due to enhanced spin polarization and/or enhanced spin-dependent scattering compared to conventional ferromagnetic materials. Each of the two pinned ferromagnetic layers may be an antiparallel (AP) pinned structure wherein first (AP1) and second (AP2) ferromagnetic layers are separated by a nonmagnetic antiparallel coupling (APC) layer with the magnetization directions AP1 and AP2 layers oriented substantially antiparallel.

Abstract: The thickness of the semiconductor layer forming a part of the spacer layer is set in the thickness range for a transitional area showing conduction performance halfway between ohmic conduction and semi-conductive conduction in relation to the junction of the semiconductor layer with the first nonmagnetic metal layer and the second nonmagnetic metal layer. This permits the specific resistance of the spacer layer to be greater than that of an ohomic conduction area, so that spin scattering and diffusion depending on a magnetized state increases, resulting in an increase in the MR ratio. The CPP-GMR device can also have a suitable area resistivity (AR) value. If the device can have a suitable area resistivity and a high MR ratio, it is then possible to obtain more stable output power in low current operation than ever before, and extend the service life of the device as well. The device is also lower in resistance than a TMR device, so that significant noise reductions are achievable.

Abstract: A spin valve sensor in a read head has a spacer layer which is located between a self-pinned AP pinned layer structure and a free layer structure. The free layer structure is longitudinally stabilized by first and second hard bias layers which abut first and second side surfaces of the spin valve sensor. The AP pinned layer structure has an antiparallel coupling layer (APC) which is located between first and second AP pinned layers (AP1) and (AP2). The invention employs a resetting process for setting of the magnetic moments of the AP pinned layers by applying a field at an acute angle to the head surface in a plane parallel to the major planes of the layers of the sensor. The resetting process sets a proper polarity of each AP pinned layer, which polarity conforms to processing circuitry employed with the spin valve sensor.

Abstract: An MR element comprises: a tunnel barrier layer having two surfaces that face toward opposite directions; a free layer disposed adjacent to one of the surfaces of the tunnel barrier layer and having a direction of magnetization that changes in response to an external magnetic field; and a pinned layer that is a ferromagnetic layer disposed adjacent to the other of the surfaces of the tunnel barrier layer and having a fixed direction of magnetization. The free layer incorporates: a first soft magnetic layer disposed adjacent to the one of the surfaces of the tunnel barrier layer; a high polarization layer disposed such that the first soft magnetic layer is sandwiched between the tunnel barrier layer and the high polarization layer; and a second soft magnetic layer disposed such that the high polarization layer is sandwiched between the first and second soft magnetic layers.

Abstract: A current perpendicular to plane magnetorestive sensor having an improved in stack biasing. An amorphous layer breaks the structure allowing a desire crystolographic structure in an in stack bias layer that provides greatly increased coercivity (Hc) in the bias layer.

Abstract: A method and structure for a spin valve transistor (SVT) comprises a magnetic field sensor, an insulating layer adjacent the magnetic field sensor, a bias layer adjacent the insulating layer, a non-magnetic layer adjacent the bias layer, and a ferromagnetic layer over the non-magnetic layer, wherein the insulating layer and the non-magnetic layer comprise antiferromagnetic materials. The magnetic field sensor comprises a base region, a collector region adjacent the base region, an emitter region adjacent the base region, and a barrier region located between the base region and the emitter region. The bias layer is between the insulating layer and the non-magnetic layer. The bias layer is magnetic and is at least three times the thickness of the magnetic materials in the base region.

Abstract: An improved TMR device is disclosed. The ferromagnetic layers of the device, particularly those that contact the dielectric tunneling layer have an amorphous structure as well as a minimum thickness (of about 15 ?). A preferred material for contacting the dielectric layer is CoFeB. Ways of overcoming problems relating to magnetostriction are disclosed and a description of a process for manufacturing the device is included.

Abstract: A current in plane giant magnetoresistive (GMR) sensor having a hard bias layer that extends along the back edge (strip height) of the sensor rather than from the sides of the sensor. The hard bias layer preferably extends beyond the track width of the sensor. Electrically conductive leads, which may be a highly conductive material such as Cu, Rh or Au, or may be an electrically conductive magnetic material extend from the sides of the sensor stack. The bias layer is separated from the sensor stack and from the leads by thin layer of electrically conductive material, thereby preventing current shunting through the hard bias layer.

Abstract: A method for achieving a nearly zero net magnetic moment of pinned layers in GMR sensors, such as Co—Fe/Ru/Co—Fe, is described. The method determines a thickness of the first pinned layer which will yield the desired net magnetic moment for the pinned layers. A series of test structures are deposited on a substrate such as glass. The test structures include the seed layers, pinning layers and pinned layers and have varying thicknesses of the first pinned layer. The compositions of the materials and the thicknesses of all of the other films remain constant. The net areal magnetic moment of each test structure is measured and plotted versus the thickness of the first pinned layer. The thickness of the first pinned layer which corresponds most closely to zero net areal magnetic moment is chosen as the design point for the sensor.

Abstract: A magneto-resistance effect head is provided with a lower conductive layer which is provided with a recessed portion, and a vertical bias layer is provided in the recessed portion. A first magnetic layer is provided on the lower conductive layer. On the first magnetic layer, layered in the following order are the non-magnetic layer, the fixed layer, the fixing layer, and the upper layer so as not to be placed immediately above the vertical bias layer. The non-magnetic layer, the fixed layer, the fixing layer, and the upper layer are buried in an insulation layer. Furthermore, an upper conductive layer is provided on the upper layer and the insulation layer. In the direction of the magnetic field applied by the vertical bias layer, the free layer is made greater in length than the fixed layer and the free layer is disposed in proximity to the vertical bias layer with the distance between the fixed layer and the vertical bias layer remaining unchanged.

Abstract: An exchange-coupled film includes a seed layer, an antiferromagnetic layer, and a ferromagnetic layer. The seed layer is formed at a thickness that is larger than the critical thickness, and the thickness of the seed layer is then decreased by etching so as to be smaller than or equal to the critical thickness. Thereby, a crystalline phase which extends through the seed layer from the upper surface to the lower surface can be formed, and/or the average size, in a direction parallel to the layer surface, of the crystal grains in the seed layer can be set to be larger than the thickness of the seed layer. Consequently, a large exchange coupling magnetic field Hex can be generated between the antiferromagnetic layer and the ferromagnetic layer.

Abstract: A magnetoresistive sensor having a shape enhanced pinning and a flux guide structure. The sensor includes a sensor stack with a pinned layer, spacer layer and pinned layer. First and second hard bias layers and lead layers extend from the sides of the sensor stack. The hard bias layers and leads have a stripe height that is smaller than the stripe height of the free layer, resulting in a free layer that extends beyond the back edge of the lead and hard bias layer. This portion of the free layer that extends beyond the back edge of the leads and hard bias layers provides a back flux guide. Similarly, the sensor may have a free layer that extends beyond the front edge of the lead and hard bias layers to provide a front flux guide. The pinned layer extends significantly beyond the back edge of the free layer, providing the pinned layer with a strong shape enhanced magnetic anisotropy.

Abstract: A spin valve sensor with an antiparallel coupled lead/sensor overlap region is provided comprising a ferromagnetic bias layer antiparallel coupled to a free layer in first and second passive regions where first and second lead layers overlap the spin valve sensor layers. The ferromagnetic material of the bias layer in a track width region defined by a space between the first and second lead layers is converted to a nonmagnetic oxide layer allowing the free layer in the track width region to rotate in response to signal fields from a magnetic disk.

Abstract: A magnetic sensor comprises magnetoresistive elements and permanent magnet films, which are combined together to form GMR elements formed on a quartz substrate having a square shape, wherein the permanent magnet films are paired and connected to both ends of the magnetoresistive elements, so that an X-axis magnetic sensor and a Y-axis magnetic sensor are realized by adequately arranging the GMR elements relative to the four sides of the quartz substrate. Herein, the magnetization direction of the pinned layer of the magnetoresistive element forms a prescribed angle of 45° relative to the longitudinal direction of the magnetoresistive element or relative to the magnetization direction of the permanent magnet film. Thus, it is possible to reliably suppress offset variations of bridge connections of the GMR elements even when an intense magnetic field is applied; and it is therefore possible to noticeably improve the resistant characteristics to an intense magnetic field.

Abstract: The present invention provides systems and method utilizing magnetoelectric materials such as Cr2O3 to construct tunneling magnetoresistence and/or giant magnetoresistence structures for memory and/or logical circuitry. An applied voltage differential induces a magnetic moment in the magnetoelectric material, which in turn tunes an exchange field between it and one or more adjacent ferromagnetic layers. The resulting magnetoresistence of the device may be measured. Devices in accordance with the present invention may be utilized for MRAM read heads, memory storage cells and/or logical circuitry such as XOR or NXOR devices.

Abstract: Magnetic tunneling devices are formed from a first body centered cubic (bcc) magnetic layer and a second bcc magnetic layer. At least one spacer layer of bcc material between these magnetic layers exchange couples the first and second bcc magnetic layers. A tunnel barrier in proximity with the second magnetic layer permits spin-polarized current to pass between the tunnel barrier and the second layer; the tunnel barrier may be either MgO and Mg—ZnO. The first magnetic layer, the spacer layer, the second magnetic layer, and the tunnel barrier are all preferably (100) oriented. The MgO and Mg—ZnO tunnel barriers are prepared by first depositing a metallic layer on the second magnetic layer (e.g., a Mg layer), thereby substantially reducing the oxygen content in this magnetic layer, which improves the performance of the tunnel barriers.