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: 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: A magnetic head includes a seed layer structure comprising Ta and NiFeCr seed layers; an antiparallel (AP) pinned layer structure formed above the NiFeCr seed layer; a free layer positioned above the AP pinned layer structure; and a layer of metal oxide positioned between the free layer and the AP pinned layer structure. A magnetic head in another embodiment includes a seed layer structure comprising Al2O3, Ta, and NiFeCr seed layers, wherein a thickness of the NiFeCr seed layer is less than about a thickness of at least one of the Al2O3 and Ta seed layers; an antiparallel (AP) pinned layer structure formed above the NiFeCr seed layer; and a free layer positioned above the AP pinned layer structure. In another embodiment, a thickness of the NiFeCr seed layer is greater than about a thickness of at least one of the Al2O3 and Ta seed layers.

Abstract: Magnetoresistance sensors with magnetic pinned layers that are pinned by anisotropic etch induced magnetic anisotropies and methods for fabricating the magnetoresistance sensors are provided. The method comprises forming a seed layer structure. The seed layer is etched to form an anisotropic etch along a top surface of the seed layer. A magnetic pinned layer is formed on the top surface of the seed layer structure. The anisotropic etch on the top surface of the seed layer structure induces a magnetic anisotropy in the magnetic pinned layer, which pins the magnetization of the magnetic pinned layer structure.

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 thin film magnetic head has: a spin valve having a pinned layer whose magnetization direction is fixed relative to an external magnetic field, a first nonmagnetic intermediate layer which is disposed on said pinned layer, and a free layer whose magnetization direction is changed according to the external magnetic field, said free layer being disposed on said first nonmagnetic intermediate layer; and bias magnetic layers for applying a bias magnetic field to said free layer, said bias magnetic layers being provided on both sides of said spin valve with regard to a track width direction thereof. The pinned layer has a hard magnetic layer, a second nonmagnetic intermediate layer which is disposed on said hard magnetic layer, and a ferromagnetic layer which is disposed on said second nonmagnetic intermediate layer. The bias magnetic layer has a bias antiferromagnetic layer, and a bias ferromagnetic layer which is disposed on said bias antiferromagnetic layer.

Abstract: An anti-parallel pinned sensor is provided with a spacer that increases the anti-parallel coupling strength of the sensor. The anti-parallel pinned sensor is a GMR or TMR sensor having a pure ruthenium or ruthenium alloy spacer. The thickness of the spacer is less than 0.8 nm, preferably between 0.1 and 0.6 nm. The spacer is also annealed in a magnetic field that is 1.5 Tesla or higher, and preferably greater than 5 Tesla. This design yields unexpected results by more than tripling the pinning field over that of typical AP-pinned GMR and TMR sensors that utilize ruthenium spacers which are 0.8 nm thick and annealed in a relatively low magnetic field of approximately 1.3 Tesla.

Abstract: A CPP MTJ or GMR read sensor is provided in which the free layer is self-stabilized by a magnetization in a circumferential vortex configuration. This magnetization permits the pinned layer to be magnetized in a direction parallel to the ABS plane, which thereby makes the pinned layer directionally more stable as well. The lack of lateral horizontal bias layers or in-stack biasing allows the formation of closely configured shields, thereby providing protection against side-reading. The vortex magnetization is accomplished by first magnetizing the free layer in a uniform vertical field, then applying a vertical current while the field is still present.

Abstract: The present invention provides a magnetic sensor suitable for high resolution and having high reliability by achieving stable output even at the occurrence of variations in a gap between a magnetic medium and the magnetic sensor, and a magnetic encoder using the magnetic sensor. The present invention uses a magnetoresistive element having magnetoresistive properties that satisfy the inequation, H10-50<H50-90, where H10-50 represents a magnetic field required for a resistance change from ?R×10% to ?R×50% with respect to a maximum amount of resistance change ?R on a magnetoresitance effect curve, and H50-90 represents a magnetic field required for a resistance change from ?R×50% to ?R×90%.

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: A current-perpendicular-to-plane (CPP) magnetoresistance sensor and a method for forming a current-perpendicular-to-plane (CPP) magnetoresistance sensor. The method includes providing a ferromagnetic shield layer and disposing one or more seed layers on the ferromagnetic shield layer. The method also includes disposing a pinning layer on the one or more seed layers, wherein the pinning layer excludes PtMn, and disposing a pinned layer on the pinning layer. The shield layer, each of the one or more seed layers, the pinning layer, and the pinned layer are comprised of compounds having face-centered-cubic structures.

Abstract: A magnetic sensor comprises a substrate, magnetoresistive element of a spin-valve type, a bias magnetic layer (or a permanent magnet film), and a protective film, wherein the bias magnetic layer is connected with both ends of the magnetoresistive element and the upper surface thereof is entirely covered with the lower surface of the magnetoresistive element at both ends. Herein, distances between the side surfaces of the both ends of the magnetoresistive element and the side surfaces of the bias magnetic layer viewed from the protective film do not exceed 3 ?m. In addition, a part of the bias magnetic layer can be covered with both ends of the magnetoresistive element, and an intermediate layer is arranged in relation to the magnetoresistive element, bias magnetic layer, and protective film so as to entirely cover the upper surface of the bias magnetic 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 structure can include a Cr under-layer having a surface that has been treated by a low power angled ion milling to form it with an anisotropic surface texture. A layer of Cr—Mo alloy is formed over the Cr under-layer and the hard magnetic material layer is formed over the Cr—Mo alloy layer. The anisotropic surface texture of the Cr layer induces an aligned crystalline structure in the hard magnetic layer that causes the hard magnetic layer to have a magnetic anisotropy.

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: This invention provides a CPP TMR or GMR sensor with an amorphous ferromagnetic lower keeper layer and a crystalline ferromagnetic upper keeper layer. The amorphous ferromagnetic lower keeper layer strongly exchange-couples to an underlying antiferromagnetic pinning layer and planarizes its rough surface. The crystalline ferromagnetic upper keeper layer strongly antiparallel-couples to an adjacent ferromagnetic reference layer across a nonmagnetic spacer layer. The amorphous ferromagnetic lower keeper layer is preferably made of a Co—Fe—B alloy film with an Fe content high enough to ensure strong exchange-coupling to the underlying antiferromagnetic pinning layer, and with a B content high enough to ensure the formation of an amorphous phase for planarizing an otherwise rough surface due to the underlying antiferromagnetic pinning layer.

Abstract: A magnetic head of either CIP or CPP configuration is disclosed, having a read sensor with a strongly pinned ferromagnetic layer due to increased electronic exchange with the AFM layer. The read sensor includes a lower seed layer whose material is chosen from a group consisting of Ta, NiFeCr, NiFeCoCr, NiFe, Cu, Ta/NiFeCr, Ta/NiFeCr/NiFe, Ta/Ru and Ta/NiFeCoCr, and an upper seed layer where the upper seed layer material is chosen from a group consisting of Ru, Cu, NiFe, Cu(x)Au(1-x)(x=0.22-0.5) alloys, Ru(x)Cr(1-x)(x=0.1-0.5) alloys, NiFeCr and NiFeCoCr. An AFM layer is formed on the upper seed layer and a ferromagnetic pinned layer is formed on the AFM layer. The exchange coupling energy Jk between the AFM layer and pinned layers exceeds 1.3 erg/cm2. Also disclosed is a method of fabrication of a magnetic head including a read head sensor with a strongly pinned ferromagnetic layer due to increased electronic exchange.

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 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 magnetic head having a free layer and an antiparallel (AP) pinned layer structure spaced apart from the free layer. 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 constructed of a Ru alloy. The use of a Ru alloy coupling layer significantly increases the pinning field of the AP pinned layer structure over a pure Ru spacer.

Abstract: CPP magnetic read head designs have been improved by increasing the length of the AFM layer relative to that of both the free and spacer layers. The length of the pinned layer is also increased, but by a lesser amount, an abutting conductive layer being inserted to fill the remaining space over the AFM layer. The extended pinned layer increases the probability of spin interaction while the added conducting layer serves to divert sensor current away from the bottom magnetic shield which now is no longer needed for use as a lead.

Abstract: A magnetic head is disclosed having a CPP read sensor including a seed layer of NiFeCr, a self-pinned structure, a spacer layer, at least one free layer, and an upper capping layer. A lower capping layer of conductive material is also preferred. An alternate embodiment includes a read sensor having an in-stack biasing structure.

Abstract: A magnetoresistive MR element 10, which is constituted by allocating a magnetic layer 22a, 22b between a sensing layer (free-magnetic layer) 11 whose magnetization rotates in response to an external magnetic field, and a bias application layer 15a, 15b for applying a bias magnetic field to the sensing layer (free-magnetic layer) 11. The components of the bias magnetic layer in the element height direction are cancelled and a stable bias magnetic field is applied to the sensing layer in the core width direction, and thereby Barkhausen noise can be prevented by forming small crystal grains with the magnetic layer 22a, 22b and transferring the bias magnetic field from the bias application layer 15a, 15b to the sensing layer (free-magnetic layer) 11 through such small crystal grains.

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: A soft magnetic layer is made of nickel iron alloy containing crystals of the face-centered cubic lattice and crystals of the body-centered cubic lattice. The face-centered cubic lattice serves to establish a soft magnetic property in the nickel iron alloy. The body-centered cubic lattice contributes to reduction in the electric resistance of the magnetoresistive film as well as to improvement of the magnetoresistive ratio of the magnetoresistive film. Even if the magnetoresistive film is further reduced in size, the magnetoresistive film can sufficiently be prevented from suffering from an increase in the temperature. Even if a sensing current of a larger current value is supplied to the magnetoresistive film, the magnetoresistive film is reliably prevented from deterioration in the characteristics as well as destruction.

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 high speed and low power method to control and switch the magnetization direction and/or helicity of a magnetic region in a magnetic device for memory cells using spin polarized electrical current. The magnetic device comprises a reference magnetic layer with a fixed magnetic helicity and/or magnetization direction and a free magnetic layer with a changeable magnetic helicity. The fixed magnetic layer and the free magnetic layer are preferably separated by a non-magnetic layer, and the reference layer includes an easy axis perpendicular to the reference layer. A current can be applied to the device to induce a torque that alters the magnetic state of the device so that it can act as a magnetic memory for writing information. The resistance, which depends on the magnetic state of the device, is measured to thereby read out the information stored in the device.

Abstract: A magnetic sensing element with improved magnetic detection output and a method for making the same are provided. In the magnetic sensing element, the length of an upper pinned magnetic layer an upper antiferromagnetic layer in a track width direction is larger than the length of a free magnetic layer in the track width direction. In making the magnetic sensing element, there is no need to remove side portions of the upper pinned magnetic layer and the upper antiferromagnetic layer. The materials of the upper pinned magnetic layer and the upper antiferromagnetic layer are thus prevented from redepositing on two side faces of the free magnetic layer during milling.

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: An exchange-coupled film includes a ferromagnetic layer and an antiferromagnetic layer disposed on each other, the magnetization direction of the ferromagnetic layer being pinned in one direction by an exchange coupling magnetic field generated at the interface between the ferromagnetic layer and the antiferromagnetic layer, wherein the antiferromagnetic layer is composed of IrzMn100-z (wherein 2 atomic percent?z?80 atomic percent), the ferromagnetic layer has a two-layer structure including a CoyFe100-y layer having a face-centered cubic structure (wherein 80 atomic percent?y?100 atomic percent), the CoyFe100-y layer being in contact with the antiferromagnetic layer, and an FexCo100-x layer (wherein x?30 atomic percent), the FexCo100-x layer being disposed on the CoyFe100-y layer, and the thickness of the FexCo100-x layer is 30% to 90% of the total thickness of the ferromagnetic layer.

Abstract: A magnetoresistive sensor having a pinned layer that extends beyond the stripe height defined by the free layer of the sensor. The extended pinned layer has a strong shape induced anisotropy that maintains pinning of the pinned layer moment. The extended portion of the pinned layer has sides beyond the stripe height that are perfectly aligned with the sides of the sensor within the stripe height. This perfect alignment is made possible by a manufacturing method that uses a mask structure for more than one manufacturing phase, eliminating the need for multiple mask alignments.

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: 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 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 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: Provided are a data storage device using a magnetic domain wall movement and a method of operating the data storage device. The data storage device includes a magnetic layer including a plurality of magnetic domains, first and second ferromagnetic pinned layers formed on lower and upper surfaces of the magnetic layer, respectively, and having opposite magnetization directions, first and second insulating spacers interposed between the first and second ferromagnetic pinned layers and the magnetic layer, respectively, and an energy supplying unit applying energy to the magnetic layer for a magnetic domain wall movement.

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: A magnetic head having an improved PtMn layer formed by ion beam deposition, an antiparallel (AP) pinned layer structure formed above the PtMn layer, and a free layer formed above the AP pinned layer structure. The spin valve structure provides improved soft magnetic properties of the free layer as well as increases the dR/R of spin valve structures in which implemented.

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: A fixed magnetic layer contains a first magnetic layer formed on a non-magnetic metal layer. The non-magnetic metal layer is composed of an X—Mn alloy (where X is selected from Pt, Pd, Ir, Rh, Ru, Os, Ni, and Fe). While atoms forming the first magnetic layer and atoms forming the non-magnetic metal layer are being aligned with each other, strains are generated in the individual crystal structures. By generating the strain in the crystal structure of the first magnetic layer, the magnetostriction constant ? is increased. As a result, a magnetic sensor having a large magnetoelastic effect can be provided.

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.

Abstract: There is provided a practical magnetoresistance effect element which has an appropriate value of resistance, which can be sensitized and which has a small number of magnetic layers to be controlled, and a magnetic head and magnetic recording and/or reproducing system using the same. In a magnetoresistance effect element wherein a sense current is caused to flow in a direction perpendicular to the plane of the film, if a pinned layer and a free layer have a stacked construction of a magnetic layer and a non-magnetic layer or a stacked construction of a magnetic layer and a magnetic layer, it is possible to provide a practical magnetoresistance effect element which has an appropriate value of resistance, which can be sensitized and which has a small number of magnetic layers, while effectively utilizing the scattering effect depending on spin.

Abstract: The present invention relates to a magnetoresistive effect element, which has a large MR ratio, excellent thermostability and a small switching magnetic field even if its size is decreased, and a magnetic memory using the magnetoresistive effect element. The magnetoresistive effect element includes: a storage layer formed by stacking a plurality of ferromagnetic layers via non-magnetic layers; a magnetic film having at least one ferromagnetic layer; and a tunnel barrier layer provided between the storage layer and the magnetic film. Each of the ferromagnetic layers of the storage layer is formed of an Ni—Fe—Co ternary alloy. A peak-to-peak maximum surface roughness on each of an interface between the storage layer and the tunnel barrier layer and an interface between the magnetic film and the tunnel barrier layer is 0.4 nm or less.

Abstract: Magnetic tunnel junctions are constructed from a MgO or Mg—ZnO tunnel barrier and amorphous magnetic layers in proximity with, and on respective sides of, the tunnel barrier. The amorphous magnetic layer preferably includes Co and at least one additional element selected to make the layer amorphous, such as boron. Magnetic tunnel junctions formed from the amorphous magnetic layers and the tunnel barrier have tunneling magnetoresistance values of up to 200% or more.

Abstract: A magnetic oscillation element includes: a magnetization fixing layer whose magnetization direction is substantially pinned toward one direction; a nonmagnetic layer that is disposed on the magnetization fixing layer; a magnetization free layer whose magnetization direction fluctuates, the magnetization free layer being disposed on the nonmagnetic layer; and a pair of electrodes that applies a current in a direction perpendicular to the film surface of the magnetization fixing layer, the nonmagnetic layer, and the magnetization free layer, wherein the magnetization free layer is excited with a magnetization vibration caused by spin transfer from the magnetization fixing layer due to the appliance of the current.

Abstract: A method for making a magnetoresistive read head so that the pinned ferromagnetic layer is wider than the stripe height of the free ferromagnetic layer uses ion milling with the ion beam aligned at an angle to the substrate supporting the stack of layers making up the read head. The stack is patterned with photoresist to define a rectangular region with front and back long edges aligned parallel to the read head track width. After ion milling in two opposite directions orthogonal to the front and back long edges, the pinned layer width has an extension. The extension makes the width of the pinned layer greater than the stripe height of the free layer after the substrate and stack of layers are lapped. The length of the extension is determined by the angle between the substrate and the ion beam and the thickness of the photoresist.

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.

Abstract: Stable anti-ferromagnetic exchange coupling can be obtained between a first pinned magnetic layer in a magnetoresistive element and a second pinned magnetic layer through smoothing of a non-magnetic intermediate layer, by smoothing the first pinned magnetic layer. The magnetoresistive element is made by sequentially laminating an underlayer, an anti-ferromagnetic layer, the first pinned magnetic layer, the non-magnetic intermediate layer, the second pinned magnetic layer, a tunnel barrier layer, a free magnetic layer, and a protection layer. The first pinned magnetic layer is smoothed before the non-magnetic intermediate layer is laminated over the first pinned magnetic layer. Stable magnetoresistive characteristics can be obtained, even when thickness is reduced, by smoothing the tunnel barrier layer. In that case, excellent magnetoresistive characteristics can also be obtained even when the tunnel barrier layer requires crystal properties.

Abstract: A perpendicular magnetic recording medium composed of a nonmagnetic substrate having a surface onto which are provided a plurality of layers including, in the order recited, a soft underlayer; a nonmagnetic coupling layer; a hard magnetic pinning layer which is antiferromagnetically coupled to the soft underlayer at ambient temperature via the nonmagnetic coupling layer and which has an axis of easy magnetization which extends in a direction which is perpendicular to that of the surface of the nonmagnetic substrate; a nonmagnetic intermediate layer; and a magnetic recording layer. Such a perpendicular magnetic recording medium has an improved medium performance, with reduced noise originating from the presence of the soft underlayer, and no erasure of recorded magnetization when influenced by an external magnetic field.

Abstract: An antiferromagnetically exchange-coupled structure for use in a magnetic device, such as a magnetoresistive sensor, includes an underlayer formed of a chemically-ordered tetragonal-crystalline alloy, a chemically-ordered tetragonal-crystalline Mn-alloy antiferromagnetic layer in contact with the underlayer, and a ferromagnetic layer exchange-coupled with the antiferromagnetic layer. The underlayer is an alloy selected from the group consisting of alloys of AuCu, FePt, FePd, AgTi3, Pt Zn, PdZn, IrV, CoPt and PdCd, and the antiferromagnetic layer is an alloy of Mn with Pt, Ni, Ir, Pd or Rh. The underlayer enhances the transformation of the Mn alloy from the chemically-disordered phase to the chemically-ordered phase.

Abstract: A pinned magnetic layer 20 and a free magnetic layer 26 include a magnetic portion 17 and a magnetic sublayer 22, respectively, each comprising a half-metallic ferromagnetic alloy. Since each of the magnetic portion 17 and magnetic sublayer 22 comprising the half-metallic alloy layer has a larger value ? and a larger resistivity ? compared to the conventional CoFe alloy or the like, the change in resistance (?R) can be increased, and the rate of change in resistance (?R/R) can be appropriately improved.