Abstract: Disclosed herein is a spin valve magnetoresistive sensor including a first conductor layer, a free ferromagnetic layer provided on the first conductor layer, a nonmagnetic intermediate layer provided on the free ferromagnetic layer, a pinned ferromagnetic layer provided on the nonmagnetic intermediate layer, an antiferromagnetic layer provided on the pinned ferromagnetic layer, and a second conductor layer provided on the antiferromagnetic layer. At least one of the free ferromagnetic layer and the pinned ferromagnetic layer has a thickness larger than that providing a maximum resistance change rate or resistance change amount in the case of passing a current in an in-plane direction of the at least one layer. That is, the thickness of at least one of the free ferromagnetic layer and the pinned ferromagnetic layer falls in the range of 3 nm to 12 nm.

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 one embodiment, the sensor has an ultra thin (<20 angstroms) single free layer and a composite high-conductance layer (HCL), providing high output, low coercivity and positive magnetostriction. In a second embodiment, the sensor has a composite free layer and a single HCL, also having high output, low coercivity and positive magnetostriction. The sensors are capable of reading densities exceeding 60 Gb/in2.

Abstract: An exchange-coupled magnetic structure includes a ferromagnetic layer, a coercive ferrite layer, such as cobalt-ferrite, for biasing the magnetization of the ferromagnetic layer, and an oxide underlayer, such as cobalt-oxide, in proximity to the coercive ferrite layer. The oxide underlayer has a lattice structure of either rock salt or a spinel and exhibits no magnetic moment at room temperature. The underlayer affects the structure of the coercive ferrite layer and therefore its magnetic properties, providing increased coercivity and enhanced thermal stability. As a result, the coercive ferrite layer is thermally stable at much smaller thicknesses than without the underlayer. The exchange-coupled structure is used in spin valve and magnetic tunnel junction magnetoresistive sensors in read heads of magnetic disk drive systems. Because the coercive ferrite layer can be made as thin as 1 nm while remaining thermally stable, the sensor satisfies the narrow gap requirements of high recording density systems.

Abstract: Hard biasing of a magnetoresistive sensor or a spin valve sensor in a magnetic read head is initialized by repeatedly applying a magnetic field to the hard biasing at any level of fabrication of the magnetic read head or any combination of levels of fabrication of the read head such as at the wafer level, row bar level, single slider level, head gimbal assembly (HGA) level and/or head stack assembly (HSA) level.

Abstract: A magnetoresistive device includes a free ferromagnetic layer; a pinned structure; and a spacer layer between the free layer and the pinned structure. The pinned structure may include first, second and third ferromagnetic layers that are ferromagnetically coupled. The first and third layers are separated by the second layer. The second layer has a lower magnetic moment than the first and third layers. In the alternative, the pinned structure may include a single layer of Co50Fe50.

Abstract: A magnetoresistive device of the type with a pinned ferromagnetic layer and a free ferromagnetic layer separated by a nonmagnetic spacer layer has an exchange-coupled antiferromagnetic/ferromagnetic structure that uses a half-metallic ferromagnetic Heusler alloy with its near 100% spin polarization as the pinned ferromagnetic layer. The exchange-coupled structure includes an intermediate ferromagnetic layer between the AF layer and the pinned half-metallic ferromagnetic Heusler alloy layer, which results in exchange biasing. Magnetoresistive devices that can incorporate the exchange-coupled structure include current-in-the-plane (CIP) read heads and current-perpendicular-to-the-plane (CPP) magnetic tunnel junctions and read heads. The exchange-coupled structure may be located either below or above the nonmagnetic spacer layer in the magnetoresistive device.

Abstract: A major problem in Lead Overlay design for GMR structures is that the magnetic read track width is wider than the physical read track width. This is due to high interfacial resistance between the leads and the GMR layer which is an unavoidable side effect of prior art methods. The present invention uses electroplating preceded by a wet etch to fabricate the leads. This approach requires only a thin protection layer over the GMR layer to ensure that interface resistance is minimal. Using wet surface cleaning avoids sputtering defects and plating is compatible with this so the cleaned surface is preserved Only a single lithography step is needed to define the track since there is no re-deposition involved.

Abstract: A method for forming top and bottom spin valve sensors and the sensors so formed, the sensors having a strongly coupled SyAP pinned layer and an ultra-thin antiferromagnetic pinning layer. The two strongly coupled ferromagnetic layers comprising the SyAP pinned layer in the top valve configuration are separated by a Ru spacer layer approximately 3 angstroms thick, while the two layers in the bottom spin valve configuration are separated by a Rh spacer layer approximately 5 angstroms thick. This allows the use of an ultra thin MnPt antiferromagnetic pinning layer of thickness between approximately 80 and approximately 150 angstroms. The sensor structure produced thereby is suitable for high density applications.

Abstract: The layer system having an increased magnetoresistive effect contains at least one soft magnetic detection layer, a non-magnetic decoupling layer, which rests on the detection layer, and a layer partial system, which is located at a distance due to the decoupling layer, forms an artificial antiferromagnet, and which is decoupled from the detection layer. This partial system comprises a first ferromagnetic and a second ferromagnetic layer. The first ferromagnetic layer should be antiferromagnetically coupled (K2) to the second ferromagnetic layer via a non-magnetic coupling layer. In addition, the side of the first ferromagnetic layer facing away from the coupling layer should be provided with an antiferromagnetic additional layer and be exchange-coupled (K3) thereto and, in addition, should have a material composition that differs from the second ferromagnetic layer.

Abstract: A magnetic head includes a seed layer structure comprising Al2O3, Ta, and NiFeCr seed layers. An antiparallel (AP) pinned layer structure is formed above the NiFeCr seed layer. A free layer is positioned above the AP pinned layer structure.

Abstract: A magnetoresistance sensor structure includes a magnetoresistance sensor having a sensor surface plane and having a free layer. An upper antiferromagnetic layer overlies at least a portion of the free layer, and an upper ferromagnetic layer overlies and contacts at least a portion of the upper antiferromagnetic layer on a contact face lying parallel to the sensor surface plane, so that the upper antiferromagnetic layer lies between the upper ferromagnetic layer and the free layer. The magnetoresistance sensor may be a giant magnetoresistance sensor or a tunnel magnetoresistance sensor.

Abstract: A spin valve sensor system and a method for fabricating the same are provided. Such spin valve sensor includes a pinned layer having a pinned layer magnetization. Also included is a free layer disposed adjacent the pinned layer. The free layer has a free layer magnetization perpendicular to the pinned layer magnetization in the absence of an external field. A pinning layer is disposed adjacent the pinned layer for fixing the pinned layer magnetization. Further included is an underlayer disposed adjacent the pinning layer. Such underlayer comprises NiFeX. Disposed adjacent the underlayer and the pinning layer is an upper layer. The upper layer comprises a material selected from the group consisting of NiFe and CoFe for increasing a GMR ratio associated with the SV sensor.

Abstract: A GMR sensor having improved longitudinal biasing is provided as is a method of forming it. The improved biasing is provided by longitudinal biasing structures in which a soft magnetic layer is interposed between a hard magnetic biasing layer and the lateral edge of the GMR sensor element. The soft magnetic layer eliminates the need for a seed layer directly between the hard magnetic layer and the GMR element and provides improved coupling to the free layer of the GMR element and a substantial reduction in random domain variations.

Abstract: The present invention aims to provide a magnetic sensor provided with a magnetoresistive effect element capable of stably maintaining a direction of magnetization in a magnetic domain of a free layer. The magnetic sensor includes a magnetoresistive effect element provided with narrow zonal portions 11a . . . 11a including a pinned layer and a free layer. Disposed below both ends of the free layer are bias magnet films 11b . . . 11b composed of a permanent magnet that applies to the free layer a bias magnetic field in a predetermined direction and an initializing coil 31 that is disposed in the vicinity of the free layer and applies to the free layer a magnetic field having the direction same as that of the bias magnetic field by being energized under a predetermined condition.

Abstract: A thermally stable spin valve sensor having an increased GMR ratio by virtue of an AP pinned layer structure in which the first and second pinned layers are separated by an AP coupling layer having a nano-oxide layer formed as an oxidized surface portion of the AP coupling layer. The nano-oxide layer provides an increase in the specular scattering, and in turn, an increase in the GMR ratio.

Abstract: A magnetic head having a pinned area, a free area, and a nanoconstricted area encompassing portions of the pinned and free areas. A first layer of magnetic material extends along the pinned and free areas. An AP coupling layer extends along the pinned area. A third layer of magnetic material is positioned above the AP coupling layer, an active portion of the third layer extending along the pinned area but not along the free area. The first and third layers have magnetic moments that are self-pinned antiparallel to each other in the pinned area and a portion of the nanoconstricted area encompassing the pinned area.

Abstract: A method is provided for preserving the transverse biasing of a GMR (or MR) read head during back-end processing. In a first preferred embodiment, the method comprises magnetizing the longitudinal biasing layers of the read head in a transverse direction, so that the resulting field at the position of the transverse biasing layer places it in a minimum of potential energy which stabilizes its direction. The field of the longitudinal biasing layer is then reset to the longitudinal direction in a manner which maintains the transverse biasing direction. In a second embodiment, a novel fixture for mounting the read head during processing includes a magnetic portion which stabilizes the transverse bias of the read head. The two methods may be used singly or in combination.

Abstract: Disclosed are a CPP magnetic sensing element employing the exchange bias method in which a sensing current is prevented from expanding in the track width direction in the multilayer film while the magnetization of the free magnetic layer is controlled properly, side reading is effectively prevented, and read output is improved, and a method for fabricating the same. First insulating layers are disposed at both sides in the track width direction of a multilayer film, a second free magnetic layer is disposed over the multilayer film and the first insulating layers, and second antiferromagnetic layers are disposed on both side regions of the second free magnetic layer.

Abstract: Provided are a magnetic transducer having good thermal stability, a thin film magnetic head, a method of manufacturing a magnetic transducer and a method of manufacturing a thin film magnetic head. A stack of an MR element has a stacked structure comprising an underlayer, a first soft magnetic layer, a second soft magnetic layer, a nonmagnetic layer, a ferromagnetic layer, an antiferromagnetic layer and a capping layer, which are stacked in this order on the underlayer. The ferromagnetic layer is divided into a bottom layer and a top layer in the direction of stack. A ferromagnetic interlayer having magnetism and having higher electrical resistance than the electrical resistance of the ferromagnetic layer is formed between the bottom layer and the top layer. The ferromagnetic interlayer magnetically integrates the bottom layer with the top layer and limits a path for electrons moving through the stack, thereby improving the rate of resistance change.

Abstract: A method of manufacturing a spin valve film, which 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 forming a succeeding film of the two the 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 whose degree of vacuum 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 spin valve sensor is provided with a negative ferromagnetic coupling field ?HFC for properly biasing a free layer and a spin filter layer is employed between the free layer and a capping layer for increasing the magnetoresistive coefficient dr/R of the spin valve sensor. A top portion of the free layer is oxidized for improving the negative ferromagnetic coupling field ?HFC when the spin filter layer is employed for increasing the magnetoresistive coefficient dr/R.

Abstract: A magnetoresistive device includes a magnetization pinned layer, a magnetization free layer, a nonmagnetic intermediate layer formed between the magnetization pinned layer and the magnetization free layer, and electrodes allowing a sense current to flow in a direction substantially perpendicular to the plane of the stack including the magnetization pinned layer, the nonmagnetic intermediate layer and the magnetization free layer. At least one of the magnetization pinned layer and the magnetization free layer is substantially formed of a binary or ternary alloy represented by the formula FeaCobNic (where a+b+c=100 at %, and a?75 at %, b?75 at %, and c?63 at %), or formed of an alloy having a body-centered cubic crystal structure.

Abstract: A magneto-resistive (MR) sensor is provided including a pinned layer, and a free layer disposed above the pinned layer. Also included is a pair of leads disposed over portions of the free layer. Further, a pinning layer is disposed below the pinned layer. Disposed below the pinning layer is an underlayer. For enhanced operation, first portions of the pinned layer disposed below the leads have a first pinned layer magnetization parallel with a free layer magnetization associated with the free layer in the absence of an external field. Further, a second portion of the pinned layer has a second pinned layer magnetization perpendicular with the free layer magnetization in the absence of the external field.

Abstract: A ferromagnetic layer of a magnetoresistive element includes a crystalline ferromagnetic sublayer and an amorphous ferromagnetic sublayer. The amorphous ferromagnetic sublayer has a smoothed surface.

Abstract: In current synthetically pinned CPP SV designs, AP2 always makes a negative contribution to the device's GMR since its magnetization direction must be anti-parallel to the pinned layer (AP1). This effect has been reduced by replacing the conventional single layer AP2, that forms part of the synthetic pinned layer, with a multilayer structure into which has been inserted at least one layer of a material such as tantalum that serves to depolarize the spin of electrons that traverse its interfaces. The result is a reduction of said negative contribution by AP2, leading to a significant increase in the GMR ratio.

Abstract: A spin-valve sensor with pinning layers comprising multiple antiferromagnetic films is disclosed. The multiple antiferromagnetic films are preferably selected from the same Mn-based (Ni—Mn or Pt—Mn) alloy system. The Mn content of the antiferromagnetic film in contact with the reference layer of the spin-valve sensor is selected in order to maximize its exchange coupling to the reference layer, thereby providing a high unidirectional anisotropy field for proper sensor operation. The Mn content of the other antiferromagnetic films not in contact with the reference layer of the spin-valve sensor is reduced in order to maximize the thermal stability and corrosion resistance of the spin-valve sensor for robust sensor operation at high temperatures in disk drive environments.

Abstract: A magnetic sensing element includes a laminate, the laminate including a first antiferromagnetic layer; a pinned magnetic layer, the magnetization direction thereof being pinned by the first antiferromagnetic layer; a nonmagnetic conductive layer; a free magnetic layer, the magnetization direction thereof being variable in response to an external magnetic field; a nonmagnetic interlayer; a ferromagnetic layer; and a second antiferromagnetic layer. The laminate has a recess extending through the second antiferromagnetic layer and the ferromagnetic layer, a bottom face of the recess lying in the nonmagnetic interlayer, the width of the bottom face in a track width direction being equal to a track width. The free magnetic layer is magnetized in a direction substantially orthogonal to the magnetization direction of the pinned magnetic layer as a result of magnetic coupling with the ferromagnetic layer. A method for making such a magnetic sensing element is also disclosed.

Abstract: A magnetoresistive sensor and a method of manufacturing the magnetoresistive sensor are provided, which can effectively increase ?RA, and which can more easily and reliably bring magnetization of a free magnetic layer and magnetization of a pinned magnetic layer into an orthogonal state than the related art. By forming the pinned magnetic layer of a multilayered structure comprising a first hard magnetic layer, a nonmagnetic layer, and a second hard magnetic layer, the magnetization of the free magnetic layer and the magnetization of the pinned magnetic layer can be more easily and reliably brought into an orthogonal state than in the related art. Also, the pinned magnetic layer can be formed in a larger film thickness than that in the related art. Accordingly, the product (?RA) of a resistance change amount (?R) and a sensor area (A) in a direction parallel to film surfaces can be increased.

Abstract: A first magnetic sublayer includes a region containing X (e.g., Cr), which extends from the interface with an antiferromagnetic layer toward a nonmagnetic intermediate sublayer, and a region not containing X, which extends from the interface with the nonmagnetic intermediate sublayer toward the antiferromagnetic layer. Consequently, both the unidirectional exchange bias magnetic field (Hex*) in the pinned magnetic layer and the rate of change in resistance (?R/R) can be improved.

Abstract: A method of making provides a smooth surface of a pinned or free layer interfacing a barrier layer in a tunnel junction sensor wherein the smooth surface is an oxidized monolayer of the pinned or free layer. After sputter depositing the pinned or free layer the layer is subjected to an oxygen (O2) atmosphere which is extremely low for a very short duration. In a preferred embodiment of the invention a partial thickness of the barrier layer is provided with a smooth surface by the same process after which a remainder thickness of the barrier layer is deposited and the barrier layer is exposed to oxygen (O2) to form an oxide of the deposited metal.

Abstract: A method and system for providing a magnetoresistive sensor and a read head that includes the magnetoresistive sensor is disclosed. The method and system include providing a pinned layer, a nonmagnetic spacer layer and a composite sensor layer. The pinned layer has a first magnetization that is pinned in a particular direction. The nonmagnetic spacer layer resides between the composite sensor layer and the pinned layer. The composite sensor layer includes a CoFe layer and a composite layer adjacent to the CoFe layer. The composite layer includes CoFe and at least one of Ta, Hf, Ti, Nb, Zr, Au, Ag, Cu, B, C, O2, H2 and N2.

Abstract: The invention is a laminated antiferromagnetically coupled (AFC) structure for use in a spin valve (SV) sensor or magnetic tunnel junction (MTJ) device, having two ferromagnetic films coupled together with an improved AFC film. Particularly the AFC film comprises an alloy material selected from the group consisting of Ru100-xmx, Os100-ymy, Ir100-ymy, Rh100-y,my, Re100-zmz, and M100-xmx, where M is an alloy of two or more materials selected from the group consisting of Ru, Os, Ir, Rh, and Re, and where m is a material selected from the group consisting of W, Ta, Mo, Nb and alloys of two or more materials selected from W, Ta, Mo, and Nb, and where x is between approximately 5 and 95 at. %, y is between approximately 10 and 90 at. %, and z is between approximately 25 and 75 at. %. The sensors may be used in magnetic heads of hard disk drives.

Abstract: Ultrafast solid state amplifiers of electrical current, including power amplification devices, use injection of spin-polarized electrons from a magnetic region into another magnetic region through a semiconductor control region and electron spin precession inside the control region induced by a magnetic field resulting from a current flowing through a conductive nanowire. The amplifiers may include magnet-semiconductor-magnet heterostructures and are able to operate on electric currents and electromagnetic waves having frequencies up to 100 GHz or more.

Abstract: An exchange coupling film has an antiferromagnetic layer made of an antiferromagnetic material containing an element X and Mn, where the element X is selected from the group of elements consisting of Pt, Pd, Ir, Rh, Ru, and Os, and combinations thereof. The antiferromagnetic layer has a region in which the ratio of the atomic percent of the element X to Mn increases in a direction towards said ferromagnetic layer. The crystalline structure of at least part of said antiferromagnetic layer has a CuAu0I type face-centered square ordered lattice.

Abstract: A giant magnetoresistive spin valve sensor is provided in which first and second ferromagnetic layers comprise a Heusler alloy. A non-ferromagnetic spacer layer is positioned between the first and second ferromagnetic layers. The non-magnetic spacer layer has an energy band which is similar to the energy bands of the Heusler alloy of the first and second ferromagnetic layers to allow a giant magnetoresistive effect to occur.

Abstract: A magnetic head at high sensitivity and with enhanced output having a magnetoresistive element of high output and optimal for use in CPP-GMR, the magnetoresistive element comprising a pinned layer 606 containing a half-metal, a free layer 608 formed on one main surface of the pinned layer 606, a spacer 607 formed between the pinned layer 606 and the free layer 608, an anti-ferromagnetic layer 603 formed on the main surface of the pinned layer 606, a soft magnetic layer 604 formed between the pinned layer 606 and the anti-ferromagnetic layer 606, and a noble-metallic layer 605 formed between the pinned layer 606 and the soft magnetic layer.

Abstract: A seed layer is formed containing Cr and an element X (wherein the element X is Fe, Ni, etc.) on a substrate layer formed from Ta, etc. At this time, the compositional ratio of the aforementioned Cr is specified to be 80 at % or more, and the seed layer is formed to have a film thickness of 20 ? or more, but 130 ? or less. According to this, the wettability of the seed layer surface can be improved remarkably compared to that heretofore attained, the unidirectional exchange bias magnetic field and rate of resistance change in the fixed magnetic layer can be increased, and it becomes possible to make the smoothness of the surface of each layer on the aforementioned seed layer excellent.

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 preferential 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 preferential setting sets a proper polarity of each AP pinned layer, which polarity conforms to processing circuitry employed with the spin valve sensor.

Abstract: A spin valve sensor includes an antiparallel (AP) pinned layer structure which is self-pinned without the assistance of an antiferromagnetic (AFM) pinning layer. A free layer of the spin valve sensor has first and second wing portions which extend laterally beyond a track width of the spin valve sensor and are exchange coupled to first and second AFM pinning layers. Magnetic moments of the wing portions of the free layer are pinned parallel to the ABS and parallel to major planes of the layers of the sensor for magnetically stabilizing the central portion of the free layer which is located within the track width.

Abstract: A seed layer is formed of a Cr film with a thickness of 15 ? or more and 50 ? or less comprising at least partially an amorphous phase, thereby enabling wettability of the surface the seed layer to be remarkably improved as compared with conventional one, the unidirectional bias magnetic field in the pinned magnetic layer to be increased, and the surface of each layer on the seed layer to have good lubricity.

Abstract: A magnetic sensing element includes a lower multilayer film including a lower pinned magnetic layer, a lower nonmagnetic layer, a free magnetic layer, an upper nonmagnetic layer, and an upper pinned magnetic layer; and an upper multilayer film including a lower pinned magnetic layer, a lower nonmagnetic layer, a free magnetic layer, an upper nonmagnetic layer, and an upper pinned magnetic layer. Each pinned magnetic layer includes a first pinned magnetic sublayer, a second pinned magnetic sublayer, and an intermediate nonmagnetic sublayer. By setting the magnetization direction of the second pinned magnetic sublayers in the lower multilayer film antiparallel to the second pinned magnetic sublayers in the upper multilayer film, the magnetic sensing element can output a pulsed signal directly when moving over a magnetization transition region.

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 spin valve sensor has an antiparallel (AP) pinned layer structure which has ferromagnetic first and second AP pinned layers that are separated by an antiparallel coupling layer. The first and second AP pinned layers are self-pinned antiparallel with respect to one another without the assistance of an antiferromagnetic (AFM) pinning layer. The spin valve sensor further includes an in-stack longitudinal biasing layer structure which is magnetostatically coupled to the free layer for longitudinally biasing a magnetic moment of the free layer parallel to an air bearing surface and parallel to major planes of the layers of the sensor. The only AFM pinning layer employed is in the biasing layer structure so that when the magnetic spins of the AFM pinning layer are set the orientations of the magnetic moments of the AP pinned layer structure are not disturbed.

Abstract: A seed layer is formed with a Cr layer in which the direction of a crystal face in at least one crystal grain is oriented in a different direction from the direction of an equivalent crystal face in another crystal grain. Consequently, wettability of the seed layer can be markedly improved and the unidirectional exchange bias magnetic field in a pinned magnetic layer can be increased while permitting the surface of each layer on the seed layer to have good lubricity.

Abstract: In magnetic read heads based on bottom spin valves the preferred structure is for the longitudinal bias layer to be in direct contact with the free layer. Such a structure is very difficult to manufacture. The present invention overcomes this problem by using a liftoff technique to form, on the free layer, a buffer layer having a trapezoidal cross-section, sloping sidewalls, and a central area of uniform thickness, whose width defines the read track. A suitable bias layer and leads are then deposited on this buffer layer.

Abstract: A magnetic head including a spin valve sensor having a sensor layer stack that includes a pinned magnetic layer, a spacer layer formed on the pinned magnetic layer, and a free magnetic layer formed on the spacer layer. In a preferred embodiment the spacer layer is comprised of CuOx. Plasma smoothing of the upper surface of the pinned magnetic layer is conducted prior to depositing the spacer layer, and a preferred plasma gas is a mixture of argon and oxygen.

Abstract: A spin valve sensor includes a spacer layer which is located between a free layer and an antiparallel (AP) pinned layer structure wherein the AP pinned layer structure includes an antiparallel coupling layer which is located between and interfaces first and second AP pinned layers with the second AP pinned layer interfacing the spacer layer. Each of the first and second AP pinned layers is composed of cobalt iron (CoFe) wherein the iron (Fe) content in the cobalt iron (CoFe) of one of the first and second AP pinned layers is greater than the iron (Fe) content in the cobalt iron (CoFe) in the other one of the first and second AP pinned layers.

Abstract: An exchange-coupled magnetic structure includes a ferromagnetic layer, a coercive ferrite layer, such as cobalt-ferrite, for biasing the magnetization of the ferromagnetic layer, and an oxide underlayer, such as cobalt-oxide, in proximity to the coercive ferrite layer. The oxide underlayer has a lattice structure of either rock salt or a spinel and exhibits no magnetic moment at room temperature. The underlayer affects the structure of the coercive ferrite layer and therefore its magnetic properties, providing increased coercivity and enhanced thermal stability. As a result, the coercive ferrite layer is thermally stable at much smaller thicknesses than without the underlayer. The exchange-coupled structure is used in spin valve and magnetic tunnel junction magnetoresistive sensors in read heads of magnetic disk drive systems. Because the coercive ferrite layer can be made as thin as 1 nm while remaining thermally stable, the sensor satisfies the narrow gap requirements of high recording density systems.

Abstract: A top-pinned magnetoresistive device includes a free ferromagnetic layer; a spacer layer on the free layer; and a pinned ferromagnetic layer on the spacer layer. At least one interface property at an upper surface of the pinned layer is adjusted during fabrication of the magnetoresistive device.

Abstract: A spin valve magnetic head, providing on a substrate, a laminated structure that has an antiferromagnetic layer, fixation layer, non-magnetic layer and unconstraint layer, and having a first underlayer of Ta, a second underlayer of NiFeCr and a third underlayer of NiFe, which underlayers are interposed between the substrate and the laminated structure.