Abstract: A “scissoring-type” current-perpendicular-to-the-plane (CPP) magnetoresistive sensor with dual ferromagnetic sensing or free layers separated by a nonmagnetic spacer layer has improved stability as a result of etch-induced uniaxial magnetic anisotropy in each of the free layers. Each of the two ferromagnetic free layers has an etch-induced uniaxial magnetic anisotropy and an in-plane magnetic moment substantially parallel to its uniaxial anisotropy in the quiescent state, i.e., the absence of an applied magnetic field. The etch-induced uniaxial anisotropy of each of the free layers is achieved either by direct ion etching of each of the free layers, and/or by ion etching of the layer on which each of the free layers is deposited. A strong magnetic anisotropy is induced in the free layers by the etching, which favors generally orthogonal orientation of the two free layers in the quiescent state.

Abstract: A magnetoresistive sensor having a scissor free layer design and no pinned layer. The sensor includes first and second free layers that have magnetizations that are oriented at 90 degrees to one another and has a third magnetic layer with a magnetization that is antiparallel coupled with one of the free layers. The antiparallel coupling of the third magnetic layer with one of the free layers, allows the sensor to be used in a tunnel valve design, having an electrically insulating barrier layer between the free layers. The tunnel valve design reduces spin torque noise in the sensor, and the presence of the third magnetic layer allows the free layers to remain bias at 90 degrees to one another in spite of interfacial coupling through the very thin barrier layer.

Abstract: A current-perpendicular-to-the-plane (CPP) spin-valve (SV) magnetoresistive sensor uses an antiparallel (AP) pinned structure and has a ferromagnetic alloy comprising Co, Fe and Si in the reference layer of the AP-pinned structure and optionally in the CPP-SV sensor's free layer. The reference layer or AP2 layer is a multilayer of a first AP2-1 sublayer that contains no Si and is in contact with the AP-pinned structure's antiparallel coupling (APC) layer, and a second AP2-2 sublayer that contains Si and is in contact with the CPP-SV sensor's spacer layer. The Si-containing alloy may consist essentially of only Co, Fe and Si according to the formula (CoxFe(100-X))(100-y)Siy where the subscripts represent atomic percent, x is between about 45 and 55, and y is between about 20 and 30.

Abstract: A method of forming a CPP-GMR spin valve having a pinned layer with an AP2/coupling/AP1 configuration is disclosed wherein the AP2 portion is a FCC-like trilayer having a composition represented by CoZFe(100-Z)/Fe(100-X)TaX/CoZFe(100-Z) or CoZFe(100-Z)/FeYCo(100-Y)/CoZFe(100-Z) where x is 3 to 30 atomic %, y is 40 to 100 atomic %, and z is 75 to 100 atomic %. Preferably, z is 90 to provide a face centered cubic structure that minimizes electromigration. Optionally, the middle layer is comprised of an Fe rich alloy such as FeCr, FeV, FeW, FeZr, FeNb, FeHf, or FeMo. EM performance is improved significantly compared to a spin valve with a conventional AP2 Co50Fe50 or Co75Fe25 single layer. MR ratio is also increased and RA is maintained at an acceptable level. The coupling layer is preferably Ru and the AP1 layer may be comprised of a lamination of CoFe and Cu layers as in [CoFe/Cu]2/CoFe.

Abstract: A method for manufacturing a manufacturing a magnetoresistive sensor that allows the sensor to be constructed with a very narrow and well controlled track width. The method includes depositing a layer of diamond like carbon over a series of sensor layers. A first mask is then formed to define a sensor, and an ion milling is performed to remove sensor material not protected by the first mask. Then, a second mask is formed, and a hard bias layer is deposited to the thickness of the sensor layers. The second mask is then lifted off and a CMP is performed to remove the first mask structure. Because all areas other than the area directly over the sensor are substantially planar a quick, gentle CMP can be used to remove the first mask layer even if the first mask is small, such as for definition of a very narrow track-width sensor.

Abstract: The invention provides a magnetoresistive device of the CPP (current perpendicular to plane) structure, comprising a magnetoresistive unit, and a first shield layer and a second shield layer which are located and formed such that the magnetoresistive unit is sandwiched between them from above and below, with a sense current applied in the stacking direction, wherein said magnetoresistive unit comprises a non-magnetic intermediate layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked and formed such that said nonmagnetic intermediate layer is sandwiched between them.

Abstract: A method of testing P2 stiffness of a magnetoresistance (MR) sensor stack including a P2 pinned layer is provided. The method comprises the step of applying an external magnetic field to the MR sensor stack. The external magnetic field is oriented substantially perpendicular to a magnetic field of the P2 pinned layer. The method further comprises varying an amplitude of the external magnetic field, measuring a change in a resistance of the MR sensor stack in response to the varying amplitude of the external magnetic field, and calculating the P2 stiffness based on the measured change in resistance.

Abstract: A magnetoresistive element includes: a detection surface that receives a magnetic field to be detected; a free layer made of a ferromagnetic material, having an end face located in the detection surface, and exhibiting a change in magnetization direction in response to the magnetic field to be detected; a pinned layer made of a ferromagnetic material, disposed away from the detection surface, and having a fixed magnetization direction; and a coupling portion made of a nonmagnetic material and coupling the free layer to the pinned layer. The coupling portion includes a nonmagnetic conductive layer that allows electrons to be conducted while conserving their spins.

Abstract: In order to increase an efficiency of spin transfer and thereby reduce the required switching current, a current perpendicular to plane (CPP) magnetic element for a memory device includes either one or both of a free magnetic layer, which has an electronically reflective surface, and a permanent magnet layer, which has perpendicular anisotropy to bias the free magnetic layer.

Abstract: Arrays of spin-valve elements that can be selectively activated to trap, hold, manipulate and release magnetically tagged biological and chemical particles, including molecules and polymers. The spin-valve elements that can be selectively activated and deactivated by applying a momentary applied magnetic field thereto. The spin valve element array can be used for selectively sorting and transporting magnetic particles one particle at a time within the array. As the magnetically tagged particles are held by the spin-valve elements, application of an auxiliary magnetic field can be used to apply tension or torsion to the held particles or to move, e.g. rotate, the trapped particles. The arrays of spin-valve elements can be used in a variety of applications including drug screening, nucleic acid sequencing, structural control and analysis of RNA/DNA and proteins, medical diagnosis, and magnetic particle susceptibility and size homogenization for other medical applications.

Abstract: Arrays of spin-valve elements that can be selectively activated to trap, hold, manipulate and release magnetically tagged biological and chemical particles, including molecules and polymers. The spin-valve elements that can be selectively activated and deactivated by applying a momentary applied magnetic field thereto. The spin valve element array can be used for selectively sorting and transporting magnetic particles one particle at a time within the array. As the magnetically tagged particles are held by the spin-valve elements, application of an auxiliary magnetic field can be used to apply tension or torsion to the held particles or to move, e.g. rotate, the trapped particles. The arrays of spin-valve elements can be used in a variety of applications including drug screening, nucleic acid sequencing, structural control and analysis of RNA/DNA and protiens, medical diagnosis, and magnetic particle susceptibility and size homogenization for other medical applications.

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: An insertion layer is provided between an AFM layer and an AP2 pinned layer in a GMR or TMR element to improve exchange coupling properties by increasing Hex and the Hex/Hc ratio without degrading the MR ratio. The insertion layer may be a 1 to 15 Angstrom thick amorphous magnetic layer comprised of at least one element of Co, Fe, or Ni, and at least one element having an amorphous character selected from B, Zr, Hf, Nb, Ta, Si, or P, or a 1 to 5 Angstrom thick non-magnetic layer comprised of Cu, Ru, Mn, Hf, or Cr. Preferably, the content of the one or more amorphous elements in the amorphous magnetic layer is less than 40 atomic %. Optionally, the insertion layer may be formed within the AP2 pinned layer. Examples of an insertion layer are CoFeB, CoFeZr, CoFeNb, CoFeHf, CoFeNiZr, CoFeNiHf, and CoFeNiNbZr.

Abstract: Improved CPP GMR devices have been fabricated by replacing the conventional seed layer (typically Ta) with a bilayer of NiCr on Ta, said seed being deposited on the NiFe layer that constitutes a magnetic shield. Additional improvement was also obtained by replacing the conventional non-magnetic spacer layer of copper with a sandwich structure of two copper layers with an NOL (nano-oxide layer) between them. A process for manufacturing the devices is also described.

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: The invention provides a magneto-resistive effect device of the CPP (current perpendicular to plane) structure, having a magneto-resistive effect unit, and a first shield layer and a second shield layer located and formed such that the magneto-resistive effect unit is sandwiched between them, with a sense current applied in a stacking direction.

Abstract: The exchange coupled film according to the present invention comprises a buffer layer including a laminate in which an amorphous layer and a hafnium layer are laminated in that order, an antiferromagnetic layer laminated on the hafnium layer of the buffer layer via an intermediate layer with a thickness of at least 2 nm, and a pinned magnetic layer laminated on the antiferromagnetic layer.

Abstract: A magnetoresistive sensor having a greatly reduced read gap. The sensor has a pinned layer structure formed above the free layer. A layer of antiferromagnetic material (AFM layer) is formed over the pinned layer structure and has a front edge disposed toward, but recessed from the air bearing surface. An electrically conductive, magnetic lead is formed over the pinned layer and AFM layer such that the lead fills a space between the AFM layer and the air bearing surface. In this way, the read gap is distance between the outermost portion of the pinned layer structure and free layer. The thickness of the AFM layer and capping layer are not included in the read gap.

Abstract: A manufacturing method of an MR element in which current flows in a direction perpendicular to layer planes, includes a step of forming on a lower electrode layer an MR multi-layered structure with side surfaces substantially perpendicular to the layer lamination plane, a step of forming a first insulation layer on at least the side surfaces of the formed MR multi-layered structure, a step of forming a second insulation layer and a magnetic domain control bias layer on the lower electrode layer, and a step of forming an upper electrode layer on the MR multi-layered structure and the magnetic domain control bias layer.

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: An MR element incorporates: a nonmagnetic conductive layer having two surfaces facing toward opposite directions; a free layer disposed adjacent to one of the surfaces of the nonmagnetic conductive layer, wherein the direction of magnetization in the free layer changes in response to an external magnetic field; and a pinned layer disposed adjacent to the other of the surfaces of the nonmagnetic conductive layer, wherein the direction of magnetization in the pinned layer is fixed to the direction orthogonal to the air bearing surface. The MR element does not include any layer provided for fixing the direction of magnetization in the pinned layer. The pinned layer incorporates a ferromagnetic layer made of a ferromagnetic material having a positive magnetostriction constant. A bottom shield gap film and a top shield gap film disposed adjacent to the MR element each have a compressive stress of 600 MPa or greater.

Abstract: A magnetic stack having a free layer having a switchable magnetization orientation, a reference layer having a pinned magnetization orientation, and a barrier layer therebetween. The stack includes an annular antiferromagnetic pinning layer electrically isolated from the free layer and in physical contact with the reference layer. In some embodiments, the reference layer is larger than the free layer.

Abstract: A bottom spin-valve GMR sensor has been fabricated that has ultra-thin layers of high density and smoothness. In addition, these layers are inherently furnished with sub-monolayer thick oxygen surfactant layers. The sensor is fabricated using a method in which the layers are sputtered in a mixture of Ar and O2. A particularly novel feature of the method is the use of a sputtering chamber with an ultra-low base pressure and correspondingly ultra-low pressure mixtures of Ar and O2 sputtering gas (<0.5 millitorr) in which the admixed oxygen has a partial pressure of less than 5×10?9 torr.

Abstract: A magnetic tunnel junction cell having a free layer, a ferromagnetic pinned layer, and a barrier layer therebetween. The free layer has a central ferromagnetic portion and a stabilizing portion radially proximate the central ferromagnetic portion. The construction can be used for both in-plane magnetic memory cells where the magnetization orientation of the magnetic layer is in the stack film plane and out-of-plane magnetic memory cells where the magnetization orientation of the magnetic layer is out of the stack film plane, e.g., perpendicular to the stack plane.

Abstract: A magnetic recording element includes a multilayer having a surface and a pair of electrodes. The multilayer has a first magnetic fixed layer whose magnetization is substantially fixed in a first direction substantially perpendicular to the surface. The multilayer also has a second magnetic fixed layer whose magnetization is substantially fixed in a second direction opposite to the first direction substantially perpendicular to the surface. A third magnetic layer is provided between the first and second magnetic layers. The direction of magnetization of the third ferromagnetic layer is variable. A first intermediate layer is provided between the first and the third magnetic layers. A second intermediate layer is provided between the second and the third magnetic layers. The pair of electrodes is capable of supplying an electric current flowing in a direction substantially perpendicular to the surface to the multilayer.

Abstract: A magnetic sensor includes a sensor stack having a first magnetic portion, a second magnetic portion, and a barrier layer between the first magnetic portion and the second magnetic portion. At least one of the first magnetic portion and the second magnetic portion includes a multilayer structure having a first magnetic layer having a positive magnetostriction adjacent to the barrier layer, a second magnetic layer, and an intermediate layer between the first magnetic layer and the second magnetic layer. The magnetic sensor has an MR ratio of at least about 80% when the magnetic sensor has a resistance-area (RA) product of about 1.0 ?·?m2.

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: 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: A method for manufacturing a magnetic field detecting element having a free layer whose magnetization direction is variable depending on an external magnetic field and a pinned layer whose magnetization direction is fixed and these are stacked with an electrically conductive, nonmagnetic spacer layer sandwiched therebetween, wherein sense current flows in a direction perpendicular to film planes of the magnetic field detecting element. The method comprises: forming a spacer adjoining layer adjacent to the spacer layer, Heusler alloy layer, and a metal layer successively in this order; and forming either at least a part of the pinned layer or the free layer by heating the spacer adjoining layer, the Heusler alloy layer, and the metal layer. The spacer adjoining layer has a layer chiefly made of cobalt and iron. The Heusler alloy layer includes metal which is silver, gold, copper, palladium, or platinum, or an alloy thereof. The metal layer is made of the same.

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: The invention provides a magneto-resistive effect device having a CPP (current perpendicular to plane) structure comprising a nonmagnetic spacer layer, and a fixed magnetized layer and a free layer stacked one upon another with said nonmagnetic spacer layer sandwiched between them, with a sense current applied in a stacking direction, wherein said free layer functions such that its magnetization direction changes depending on an external magnetic field, and is made up of a multilayer structure including a Heusler alloy layer, wherein an Fe layer is formed on one of both planes of said Heusler alloy layer in the stacking direction, wherein said one plane is near to at least a nonmagnetic spacer layer side, and said fixed magnetization layer is made up of a multilayer structure including a Heusler alloy layer, wherein Fe layers are formed on both plane sides of said Heusler alloy layer in the stacking direction with said Heusler alloy layer sandwiched between them.

Abstract: A magneto-resistive effect device of a CPP structure includes a nonmagnetic intermediate layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked together and formed with the nonmagnetic intermediate layer sandwiched between them. The first ferromagnetic layer and the second ferromagnetic layer are magnetically coupled via the nonmagnetic intermediate layer such that magnetizations of the first ferromagnetic layer and the second ferromagnetic layer are antiparallel with each other. Mutually antiparallel magnetizations of two magnetic layers lie in a medium opposite plane or front to rear direction and in a rear to front direction. The second ferromagnetic layer is divided by a nonmagnetic intervening layer into a front second ferromagnetic layer and a rear second ferromagnetic layer on the way from the front to the rear.

Abstract: The invention provides a thin-film magnetic head having a magneto-resistive effect device of the CPP (current perpendicular to plane) structure comprising a multilayer film in which a fixed magnetization layer, a nonmagnetic layer and a free layer are stacked together in order. The fixed magnetization layer, nonmagnetic layer and free layer extend away from an air bearing surface that is a plane in opposition to a medium, the length of the fixed magnetization layer in a depth direction normal to said air bearing surface is greater than the length of the free layer in the depth direction. A shunt layer for shunting the sense current is located at a farther distance in the depth direction than the free layer, and the shunt layer is separated from the free layer by a constant gap in the depth direction.

Abstract: A process is described for the fabrication of a magnetic read head in which contact between the pinned layer and the AFM is limited to their edges. The principal steps are to deposit an antiferromagnetic layer and to then pattern it into a pair of antiferromagnetic layers separated by no more than about 2 microns. A layer of magnetic material that lies between, and is in contact with, said antiferromagnetic layers is then deposited, following which the layer of magnetic material is magnetized.

Abstract: A current-perpendicular-to-the-plane spin-valve (CPP-SV) magnetoresistive sensor has a ferromagnetic alloy comprising Co, Fe and Ge in the sensor's free layer and/or pinned layer and a spacer layer of Ag, Cu or a AgCu alloy between the free and pinned layers. The sensor may be a simple pinned structure, in which case the pinned layer may be formed of the CoFeGe ferromagnetic alloy. Alternatively, the sensor may have an AP-pinned layer structure, in which case the AP2 layer may be formed of the CoFeGe ferromagnetic alloy. The Ge-containing alloy comprises Co, Fe and Ge, wherein Ge is present in the alloy in an amount between about 20 and 40 atomic percent, and wherein the ratio of Co to Fe in the alloy is between about 0.8 and 1.2. More particularly, the CoFeGe alloy may consist essentially of only Co, Fe and Ge according to the formula (CoxFe(100-x))(100-y)Gey where the subscripts represent atomic percent, x is between about 45 and 55, and y is between about 23 and 37.

Abstract: A magnetoresistive device includes a free layer, a separating layer, a pinned layer, and a magnetic stabilizer in close proximity to the pinned layer, wherein the magnetic stabilizer may enhance the stability of the magnetization direction of the pinned layer.

Abstract: Embodiments of the present invention provides sufficiently high exchange coupling with a magnetic layer and improve the yield and reliability of a magnetoresistive head. By using a tilted growth crystalline structured antiferromagnetic film manufactured by an oblique incident deposition method, a high exchange coupling field with a ferromagnetic film can be obtained. As a result, excellent reliability and high output can be obtained in a magnetoresistive head utilizing features in accordance with embodiments of the present invention.

Abstract: A method and system for providing a magnetic transducer are disclosed. The method and system include providing a magnetic element that includes a free layer, a pinned layer, and a nonmagnetic spacer layer between the free layer and the pinned layer. The nonmagnetic spacer layer is a tunneling barrier layer. The free layer is configured to be biased in a first direction. The pinned layer has a pinned layer magnetization configured to be pinned in a second direction that is at a first angle from perpendicular to the ABS. The first angle is nonzero and different from ninety degrees. The second direction and the first direction form a second angle that is different from ninety degrees.

Abstract: A method and apparatus for providing a magnetic read sensor having a thin pinning layer and improved magnetoresistive coefficient ?R/R is disclosed. A thin IrMn alloy pinning layer is disposed adjacent a composite pinned layer, wherein the percentage of iron in the pinned layer adjacent the thin IrMn alloy pinning layer in the range of 20-40% to provide maximum pinning.

Abstract: An MR element in a CPP structure includes a spacer layer made of Cu, a magnetic pinned layer containing CoFe and a free layer containing CoFe that are laminated to sandwich the spacer layer. The free layer is located below the magnetic pinned layer. The free layer is oriented in a (001) crystal plane, the spacer layer is formed and oriented in a (001) crystal plane on the (001) crystal plane of the free layer. Therefore, in a low resistance area where an area resistivity (AR) of the MR element is, for example, lower than 0.3 ?·?m2, an MR element that has a large variation of a resistance is obtained.

Abstract: A thin film magnetic head has: a spin valve having a pinned layer whose having a fixed magnetization direction, a first nonmagnetic intermediate layer disposed on the pinned layer, and a free layer having a variable magnetization direction, the free layer disposed on the first nonmagnetic intermediate layer; and bias magnetic layers for applying a bias magnetic field to the free layer provided on both sides of the spin valve. The pinned layer has a hard magnetic layer, a second nonmagnetic intermediate layer disposed on the hard magnetic layer, and a ferromagnetic layer disposed on the second nonmagnetic intermediate layer. The bias magnetic layer has a bias antiferromagnetic layer, and a bias ferromagnetic layer disposed on the bias antiferromagnetic layer. A height direction dimension of the pinned layer is longer than a track width direction dimension, and longer than a height direction dimension of the free layer.

Abstract: A magneto-resistive effect element is provided with a first soft magnetic layer, a magneto-resistive effect film formed directly on the first soft magnetic layer. and a second soft magnetic layer formed on the magneto-resistive effect film. The magneto-resistive effect element is configured as allowing electric current to flow in the thickness-wise direction. The first soft magnetic layer is composed of columnar crystals. The magneto-resistive effect film has an anti-ferromagnetic layer. The anti-ferromagnetic layer is formed directly on the first soft magnetic layer.

Abstract: A magnetoresistance element includes an antiferromagnetic layer, a fixed ferromagnetic layer, a first nonmagnetic layer and a free ferromagnetic layer. The antiferromagnetic layer is formed on the upper surface side of a substrate. The fixed ferromagnetic layer is formed on the antiferromagnetic layer. The first nonmagnetic layer is formed on the fixed ferromagnetic layer. The free ferromagnetic layer is formed on the first nonmagnetic layer. The fixed ferromagnetic layer is provided with an amorphous layer. The amorphous layer contains amorphous material having a composition expressed by a chemical formula of X—Y—N. X is an element selected from Co, Fe and Ni. Y is an element selected from AI, Si, Mg, Ta, Nb, Zr, Hf, W, Mo, Ti and V. N represents nitrogen.

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: Magnetoresistive structures, devices, memories, and methods for forming the same are presented. For example, a magnetoresistive structure includes a first ferromagnetic layer, a first nonmagnetic spacer layer proximate to the first ferromagnetic layer, a second ferromagnetic layer proximate to the first nonmagnetic spacer layer, and a first antiferromagnetic layer proximate to the second ferromagnetic layer. For example, the first ferromagnetic layer may comprise a first pinned ferromagnetic layer, the second ferromagnetic layer may comprise a free ferromagnetic layer, and the first antiferromagnetic layer may comprise a free antiferromagnetic layer.

Abstract: A magnetic sensor includes a single substrate, a conventional GMR element formed of a spin-valve film including a single-layer-pinned fixed magnetization layer, and a SAF element formed of a synthetic spin-valve film including a plural-layer-pinned fixed magnetization layer. When the spin-valve film intended to act as the conventional GMR element and the synthetic spin-valve film intended to act as the SAF element are subjected to the application of a magnetic field oriented in a single direction at a high temperature, they become giant magnetoresistive elements whose magnetic-field-detecting directions are antiparallel to each other. Since films intended to act as the conventional GMR element and the SAF element can be disposed close to each other, the magnetic sensor which has giant magnetoresistive elements whose magnetic-field-detecting directions are antiparallel to each other can be small.

Abstract: A method for driving a spin valve element, including passing driving current through the spin valve element to generate an oscillation signal, and performing amplitude modulation of the driving current at a frequency lower than the oscillation frequency of oscillation signals. This amplitude modulation can be ON-OFF modulation, and the interval ton in the conducting state of the ON-OFF modulation is made to satisfy the relation ton<D2/?, where ? is the thermal diffusivity of the heat diffusion portion, and D is the thickness of the heat diffusion portion.

Abstract: A magnetoresistive stack includes a free layer, a separating layer, a pinned layer, and a magnetic stabilizer in close proximity to the pinned layer such that such that the magnetic stabilizer enhances the stability of the magnetization direction of the pinned layer.

Abstract: A method and apparatus for detecting the presence of magnetic beads is disclosed. By providing both a static magnetic field and a magnetic field that alternates in the MHz range, or beyond, the bead can be excited into FMR (ferromagnetic resonance). The appearance of the latter is then detected by a magneto-resistive type of sensor. This approach offers several advantages over prior art methods in which the magnetic moment of the bead is detected directly.

Abstract: A MTJ structure is disclosed in which the seed layer is made of a lower Ta layer, a middle Hf layer, and an upper NiFe or NiFeX layer where X is Co, Cr, or Cu. Optionally, Zr, Cr, HfZr, or HfCr may be employed as the middle layer and materials having FCC structures such as CoFe and Cu may be used as the upper layer. As a result, the overlying layers in a TMR sensor will be smoother and less pin dispersion is observed. The Hex/Hc ratio is increased relative to that for a MTJ having a conventional Ta/Ru seed layer configuration. The trilayer seed configuration is especially effective when an IrMn AFM layer is grown thereon and thereby reduces Hin between the overlying pinned layer and free layer. Ni content in the NiFe or NiFeX middle layer is above 30 atomic % and preferably >80 atomic %.