Abstract: A perpendicular magnetic recording system has a write head having a main coil (the write coil) and main pole (the write pole) that directs write flux in a direction perpendicular to the recording layer in the magnetic recording medium, and a transverse auxiliary pole (TAP) that injects auxiliary magnetic flux into the write pole at an angle to the primary or perpendicular axis of the write pole. The additional flux from the TAP, which is injected non-parallel to the primary magnetization of the write pole, exerts a torque on the magnetization of the write pole, thereby facilitating magnetization reversal of the write pole. The TAP is coupled to the main coil but not electrically connected to it. A separate passive coil, not electrically connected to the main coil, may be wrapped as a loop around the main pole and the TAP. Alternatively, the TAP may be located near one of the electrically conductive turns of the main coil.

Abstract: The present invention provides a ferromagnetic/antiferromagnetic coupling film structure and a fabrication method thereof. The structure includes an antiferromagnetic layer of cobalt oxide having a thickness of 2 to 15 monolayers and formed on a substrate at a temperature ranging from 700K to 900K; and a ferromagnetic layer of cobalt having a thickness of at least one monolayer for being formed on the antiferromagnetic layer of cobalt oxide.

Abstract: An extraordinary magnetoresistive sensor (EMR sensor) having reduced size and increased resolution is described. The sensor includes a plurality of electrically conductive leads contacting a magnetically active layer and also includes an electrically conductive shunt structure. The electrically conductive leads of the sensor and the shunt structure can be formed in a common photolithographic masking and etching process so that they are self aligned with one another. This avoids the need to align multiple photolithographic processing steps, thereby allowing greatly increased resolution and reduced lead spacing. The EMR sensor can be formed with a magnetically active layer that can be close to or at the air bearing surface (ABS) for improved magnetic spacing with an adjacent magnetic medium of a data recording system.

Abstract: A magneto-resistance effect element, a magneto-resistance effect head, a magnetic storage and a magnetic memory, in which noise caused by a spin-transfer torque is reduced, are provided. In a fixed magnetization layer or a free magnetization layer of a magneto-resistance effect element including the fixed magnetization layer, a spacer layer and the free magnetization layer; a layer containing one element selected from the group consisting of Ti, Zr, Nb, Mo, Ru, Rh, Pd, Ag, La, Hf, Ta, W, Re, Os, Ir, Pt and Au is disposed.

Abstract: A hard bias (HB) structure for longitudinally biasing a free layer in a MR sensor is disclosed that is based on HB easy axis growth perpendicular to an underlying seed layer which is formed above a substrate and along two sidewalls of the sensor. In one embodiment, a conformal soft magnetic layer that may be a top shield contacts the HB layer to provide direct exchange coupling that compensates HB surface charges. Optionally, a thin capping layer on the HB layer enables magneto-static shield-HB coupling. After HB initialization, HB regions along the sensor sidewalls have magnetizations that are perpendicular to the sidewalls as a result of surface charges near the seed layer. Sidewalls may be extended into the substrate (bottom shield) to give enhanced protection against side reading. The top surface of the seed layer may be amorphous or crystalline to promote HB easy axis perpendicular growth.

Abstract: A magneto-resistive reader includes a first magnetic shield element, a second magnetic shield element and a magneto-resistive sensor stack separating the first magnetic shield element from the second magnetic shield element. The first shield element includes two ferromagnetic anisotropic layers separated by a grain growth suppression layer.

Abstract: A magnetoresistive sensor having a trilayer sensor stack with two ferromagnetic freelayers separated by a nonmagnetic spacer layer is disclosed. The sensor is biased with a back biasing magnet adjacent a back of the trilayer sensor. The back biasing magnet, the trilayer sensor stack, or both have substantially trapezoidal shapes to enhance the biasing field and to minimize noise. In some embodiments, the trilayer sensor or back bias magnet have a shape designed to stabilize a micromagnetic “C” shape or concentrate magnetic flux in the trilayer sensor stack.

Abstract: A spin-injection magnetoresistance effect element that can avoid use of a large writing current and allows use of a large reading current. The spin-injection magnetoresistance effect element includes layers that may exhibit a tunnel magnetoresistance effect and layers that may exhibit a giant magnetoresistance effect.

Abstract: The present invention provides apparatus and method for controlling the asymmetrical properties of the response of a magnetic sensor element to a magnetic field produced by the digital data in a magnetic storage device. The present invention also provides an apparatus and method for controlling the bias point of a magnetic field produced by a magnetic sensor element.

Abstract: A magnetoresistive effect element includes a magnetization fixed layer having substantially fixed magnetization direction. A magnetization variable layer has a variable magnetization direction, consists of a magnetic alloy that has a BCC structure and is expressed by Fe1-x-yCoxNiy (0?x+y?1, 0?x?1, 0?y?1), and contains at least one additive element of V, Cr, and Mn in a range of 0<a?20 at % (a is a content). An intermediate layer is disposed between the magnetization fixed layer and the magnetization variable layer and consists of a nonmagnetic material. The magnetization direction of the magnetization variable layer is switched by a bidirectional current passing through the magnetization fixed layer, the intermediate layer, and the magnetization variable layer.

Abstract: A spin accumulation sensor having a three terminal design that allows the free layer to be located at the air bearing surface. A non-magnetic conductive spin transport layer extends from a free layer structure (located at the ABS) to a reference layer structure removed from the ABS. The sensor includes a current or voltage source for applying a current across a reference layer structure. The current or voltage source has a lead that is connected with the non-magnetic spin transport layer and also to electric ground. Circuitry for measuring a signal voltage measures a voltage between a shield that is electrically connected with the free layer structure and the ground. The free layer structure can include a spin diffusion layer that ensures that all spin current is completely dissipated before reaching the lead to the voltage source, thereby preventing shunting of the spin current to the voltage source.

Abstract: A magnetoresistive effect device includes an underlayer, an antiferromagnetic layer, a first ferromagnetic layer, a nonmagnetic layer, and a second ferromagnetic layer which are multilayered in this order on a substrate. The underlayer is formed of a metal nitride, and the antiferromagnetic layer is formed of an antiferromagnetic material including Ir and Mn.

Abstract: A method for manufacturing magnetic field detection devices comprises the operations of manufacturing a magneto-resistive element comprising regions with metallic conduction and regions with semi-conductive conduction. The method comprises the following operations: forming metallic nano-particles to obtain regions with metallic conduction; providing a semiconductor substrate; and applying metallic nano-particles to the porous semiconductor substrate to obtain a disordered mesoscopic structure. A magnetic device comprises a spin valve, which comprises a plurality of layers arranged in a stack which in turn comprises at least one free magnetic layer able to be associated to a temporary magnetisation (MT), a spacer layer and a permanent magnetic layer associated to a permanent magnetisation (MP). The spacer element is obtained by means of a mesoscopic structure of nanoparticles in a metallic matrix produced in accordance with the inventive method for manufacturing magneto-resistive elements.

Abstract: A method of measuring temperature of a TMR element includes a step of obtaining in advance a temperature coefficient of element resistance of a discrete TMR element that is not mounted on an apparatus, by measuring temperature versus element resistance value characteristic of the discrete TMR element in a state that a breakdown voltage is intentionally applied to the discrete TMR element and a tunnel barrier layer of the discrete TMR element is brought into a stable conductive state, a step of bringing a tunnel barrier layer of a TMR element actually mounted on the apparatus into a stable conductive state by intentionally applying the breakdown voltage to the mounted TMR element having the same structure as that of the discrete TMR element whose temperature coefficient has been measured, a step of measuring an element resistance value of the mounted TMR element with the tunnel barrier layer that has been brought into a stable conductive state, and a step of obtaining a temperature corresponding to the measure

Abstract: An apparatus, system, and method comprise a magnetoresistive head configured to respond to magnetization states of patterned cells formed on a patterned medium. The magnetoresistive head detects the magnetization states of at least two patterned cells formed on a patterned medium. The magnetoresistive head generates a readback signal based on the magnetization state of the at least two patterned cells. A detector circuit coupled to the head determines a bit pattern corresponding to the readback signal. A processor circuit coupled to the detector circuit determines positional information associated with the magnetoresistive head relative to the at least two patterned cells based on the bit pattern. The system further comprises a patterned medium.

Abstract: According to one embodiment, a disk drive having a spin torque oscillator and designed to perform high frequency assisted writing. The disk drive has a magnetic disk, a magnetic head, a coil, and a drive current controller. The drive current controller controls a drive current to supply to the spin torque oscillator. To record data magnetically in the disk, the drive current controller supplies to the spin torque oscillator the drive current that changes in synchronism with the polarity inversion of the recording current supplied to the coil, which excites the recording magnetic pole of the magnetic head.

Abstract: A method of bonding a metal ball for a magnetic head assembly is provided. The method comprises: preparing a capillary; disposing the capillary so as to face a bonding surface of the electrode pad of the slider and that of the electrode pad of the flexible printed circuit board; carrying the metal ball to the bonding surfaces by introducing the metal ball and the inactive gas stream into the carrying route of the capillary; positioning and retaining the metal ball on the bonding surfaces by the inactive gas stream passing through the carrying route and issued radially from the cutoff portions; and melting the metal ball by directly applying laser beams via the cutoff portions of the capillary, and bonding the electrode pad of the slider and the electrode pad of the flexible printed circuit board by the melted metal.

Abstract: Provided is a smear-removing method that can remove smear of a manufactured thin-film magnetic head. The method is performed to a thin-film magnetic head including an MR effect element for reading data having two electrode layers sandwiching an MR effect multilayer as a magneto-sensitive portion therebetween. The method comprises the step of applying a stress voltage less than a breaking voltage of the MR effect element between the two electrode layers to burn off smear. In the method, it is preferable that the stress voltage is applied while an electric resistance or an output voltage of the MR effect element is measured, and the stress voltage is increased until the value of the electric resistance or the output voltage reaches an upper limit specified value specified from a value of an electric resistance or an output voltage in a normal case where smear is not present.

Abstract: In one aspect described herein, a read head having one or more magnetoresistive (MR) sensors (or devices) is provided. In one example, the read head includes an MR sensor and an insulator layer disposed at the same level as the MR sensor. The read head further includes a bearing surface, wherein the insulator layer forms a portion of the bearing surface and is disposed between a surface of the MR sensor and the bearing surface to provide protection for the MR sensor from exposure to the bearing surface. The MR sensor may include a stack of thin-film layers to form an AMR, GMR, or TGMR sensor element. The stack may further include a slanted surface portion, wherein the insulator layer is disposed on the slanted surface portion, thereby recessing the MR sensor from the bearing surface.

Abstract: A heat extractor to transfer heat generated by the coil of a magnetic read head to a substrate, when there is at least one thermally insulating layer between the coil and the substrate, is disclosed, together with a method for its manufacture.

Abstract: Various embodiments of the present invention provide systems and methods for reducing head distortion. For example, various embodiments of the present invention provide storage devices that include a storage medium, a read/write head assembly, and an adaptive distortion modification circuit. The storage medium includes information that may be sensed by the read/write head assembly that is disposed in relation to the storage medium. The adaptive distortion modification circuit receives the information sensed by the read/write head assembly and adaptively estimates and implements a distortion compensation factor in the analog domain. In some instances of the aforementioned embodiments, the read/write head assembly includes a magneto resistive head. In such instances, the distortion compensation factor is designed to compensate for non-linear distortion introduced by the magneto resistive head.

Abstract: A thin film magnetic head includes a magnetoresistance (MR) layered body that has first and second magnetic layers whose magnetization direction are changed according to an external magnetic field, a nonmagnetic middle layer and where the first magnetic layer, the nonmagnetic middle layer and the second magnetic layer are disposed in a manner of facing each other in respective order, first and second shield layers that are disposed in a manner of sandwiching the MR-stack in the film surface orthogonal direction of the MR-stack facing the first magnetic layer and the second magnetic layer, respectively, and that also serve as an electrode for applying a sense current to the film surface orthogonal direction of the MR-stack; and a bias magnetic field application means that is disposed on an opposite surface of an air bearing surface (ABS) of the MR-stack, and that applies a bias magnetic field to the MR-stack in the direction orthogonal to the ABS.

Abstract: A magnetic device includes first and second electrodes and a sensor stack connected to the first and second electrodes proximate a sensing surface of the magnetic sensor. A resistive element is connected to the first and second electrodes in parallel or in series with the sensor stack and adjacent the sensing surface. In some embodiments, the resistive element is configured to generate signals related to changes in its resistance. A controller to respond to the resistive element signals can also be included.

Abstract: A magnetic detection element capable of maintaining the ?RA at a high level and reducing the magnetostriction by improving a material for a free magnetic layer, as well as a method for manufacturing the same, is provided. The free magnetic layer includes a laminate composed of a CoMnX alloy layer formed from a metal compound represented by a compositional formula CoaMnbXc (where X represents at least one of Ge, Ga, In, Si, Pb, Zn, and Sb and a+b+c=100 atomic percent) and a CoMnZ alloy layer formed from a metal compound represented by a compositional formula CodMneZf (where Z represents at least one of Sn and Al and d+e+f=100 atomic percent). In this manner, the magnetostriction of the free magnetic layer can be reduced.

Abstract: A Lorenz magnetoresistive sensor having a pair of voltage leads and a pair of current leads. The voltage leads are located at either side of one of the current leads and are separated by a distance that is substantially equal to the length of a bit to be measured. The Lorenz magnetoresistive sensor can be, for example an extraordinary magnetoresistive sensor having a quantum well structure such as a two dimensional electron gas and a shunt structure formed on an edge of the quantum well structure opposite the voltage and current leads.

Abstract: A magnetic head of the present application has a sensor which employs the extraordinary magnetoresistance (EMR) effect. The magnetic head includes a body of semiconductor material positioned over a tail end of a carrying mechanism; a field receiving surface of the body oriented perpendicular to a sensing plane of the magnetic head; an electrically conducting shunt coupled to a first end of the body; a plurality of electrically conducting contacts coupled to a second end of the body opposite the first end; and a magnetic flux guide having a first end at least partially formed over the field receiving surface and a second end exposed at the sensing plane. Advantageously, the magnetic flux guide orients a signal field of recorded data from a magnetic medium in a suitable direction for the field receiving surface, at least partially shields the field receiving surface magnetically, and allows for positioning of the magnetic head on the tail end of the carrying mechanism.

Abstract: According to one embodiment, a CPP structure magnetoresistive head includes a magnetoresistive sensor film between a lower shield layer and an upper shield layer and a longitudinal biasing layer disposed at each side of the magnetoresistive sensor film via a read track width defining insulator film. In the stripe height direction, the length of the longitudinal biasing layer is longer than the length of a second ferromagnetic layer in which its magnetization rotates in response to the external magnetic field. The second ferromagnetic layer is one of the layers comprising the magnetoresistive sensor film. At a stripe height, the surface of each longitudinal biasing layer has a step to change the thickness thereof across the step so that the air bearing surface section thereof has a larger thickness than any other section. Other structures using a magnetoresistive head and methods of production thereof are described as well.

Abstract: A method of manufacturing a magnetoresistive (MR) effective element having a pair of magnetic layers and a nonmagnetic intermediate layer including a ZnO film, wherein a relative angle of magnetization directions of the pair of magnetic layers varies according to an external magnetic field. The method includes a step for introducing a mix gas of oxygen gas and argon gas into a depressurized chamber, wherein a first target of ZnO, a second target of Zn and a substrate having a right-below layer are disposed in the chamber, and a step for depositing the ZnO film on the right-below layer by applying each of a first and second direct current (DC) application power to spaces between the first and second targets and the substrate respectively after the mix gas introducing step, wherein the first and second targets are set at negative potential, and the substrate is set at positive potential.

Abstract: A magnetic structure in one embodiment includes a tunnel barrier layer; a free layer; and a buffer layer between the tunnel barrier layer and the free layer, wherein a cross sectional area of the tunnel barrier layer in a direction parallel to a plane of deposition thereof is greater than a cross sectional area of the free layer in a direction parallel to a plane of deposition thereof, wherein a cross sectional area of the buffer layer in a direction parallel to a plane of deposition thereof is greater than a cross sectional area of the free layer in the direction parallel to the plane of deposition thereof. Additional systems and methods are also presented.

Abstract: A multi-channel thin-film magnetic head includes a head section provided with a plurality of thin-film magnetic head elements and a sliding surface for a magnetic tape, a slot section running in a direction perpendicular to a magnetic tape transport direction, the slot section being arranged adjacent to the head section in the magnetic tape transport direction, and an outrigger section provided with a sliding surface for the magnetic tape and arranged to separate from the head section by the slot section in the magnetic tape transport direction. The sliding surface of the outrigger section includes a sloped surface with a height that reduces as approaching the head section.

Abstract: A thermally assisted magnetic head has a medium-facing surface facing a medium, and comprises: a waveguide an end face of which is exposed in the medium-facing surface; an electroconductive near-field light generator plate disposed on a medium-facing surface of the waveguide so that a principal face thereof faces the medium; and an electroconductive near-field light scatter plate disposed on the medium-facing surface of the thermally assisted magnetic head so that a principal face thereof faces the medium; when viewed from a direction perpendicular to the medium-facing surface, the near-field light generator plate has a cusp portion at an end; when viewed from the direction perpendicular to the medium-facing surface, the near-field light scatter plate is arranged along the other end opposite to the cusp portion of the near-field light generator plate; when viewed from the direction perpendicular to the medium-facing surface, a width of the near-field light scatter plate in a first direction perpendicular to a

Abstract: A magnetoresistive element includes a pair of shield portions, and an MR stack and a bias magnetic field applying layer that are disposed between the pair of shield portions. The shield portions respectively include single magnetic domain portions. The MR stack includes a pair of ferromagnetic layers magnetically coupled to the pair of single magnetic domain portions, and a spacer layer disposed between the pair of ferromagnetic layers. The MR stack has a front end face, a rear end face and two side surfaces. The magnetoresistive element further includes two flux guide layers disposed between the pair of single magnetic domain portions and respectively adjacent to the two side surfaces of the MR stack. Each of the two flux guide layers has a front end face and a rear end face. The bias magnetic field applying layer has a front end face that faces the rear end face of the MR stack and the respective rear end faces of the two flux guide layers.

Abstract: A method for manufacturing a magneto-resistance effect element is provided. The magneto-resistance effect element includes a first magnetic layer including a ferromagnetic material, a second magnetic layer including a ferromagnetic material and a spacer layer provided between the first magnetic layer and the second magnetic layer, the spacer layer having an insulating layer and a conductive portion penetrating through the insulating layer. The method includes: forming a film to be a base material of the spacer layer; performing a first treatment using a gas including at least one of oxygen molecules, oxygen atoms, oxygen ions, oxygen plasma and oxygen radicals on the film; and performing a second treatment using a gas including at least one of helium ions, helium plasma, helium radicals, neon ions, neon plasma and neon radicals on the film submitted to the first treatment.

Abstract: An apparatus and method for determining a head parameter value (e.g., head resistance) of a resistive head. A test head current is supplied to the head during a head parameter measurement interval using the same current sources that supply a bias current to the head during an operating (read operation) interval. The determined head parameter value is latched for use in setting the control loop gain for a control loop that controls the current sources during the operating interval.

Abstract: A digital MR sensor with a high magnetoresistance ratio is provided. The MR sensor includes a first magnetic element; and a second magnetic element at least a part of which is resiliently deformable so as to contact with or be separated from the first magnetic element according to a direction of a magnetic force generated between the first and second magnetic elements while the second magnetic element is magnetized under influence of an external magnetic field.

Abstract: A method of manufacturing a GMR, TMR or CPP GMR sensor having a smooth interface between magnetic and non-magnetic layers to improve sensor performance by exposing a layer to a low energy ion beam prior to depositing a subsequent layer.

Abstract: In one general embodiment, a magnetic head includes a module having a substrate and a gap, the gap having an array of transducers therein, wherein the gap is recessed from a plane extending across a tape bearing surface side of the substrate; and a coating of aluminum oxide above at least a tape bearing surface side of the gap, the aluminum oxide having polycrystalline portions and amorphous portions.

Abstract: A magnetic oscillating device including a first magnetic resonance layer with a first magnetic resonance frequency f1, a second magnetic resonance layer with a second magnetic resonance frequency f2 higher than the first magnetic resonance frequency f1, a nonmagnetic layer sandwiched between the first magnetic resonance layer and the second magnetic resonance layer, and a pair of electrodes which supplies a current perpendicularly to film planes of the first and second magnetic resonance layers, in which a difference (f2?f1) between the two magnetic resonance frequencies is larger than half a resonance line width of the first magnetic resonance layer, and a ratio of the two magnetic resonance frequencies f2/f1 is 1.6 or less.

Abstract: A read system for a hard disk drive comprising a disk having magnetic fields. The read system comprises a read element, a bias source, a temperature sensor, and a controller. The resistance of the read element changes based on the magnetic fields. The bias source applies a bias level to the read element. The temperature sensor generates a temperature signal indicative of a head ambient temperature. The controller adapts the bias level based on the temperature signal.

Abstract: The present invention provides a tunnel magnetoresistive thin film having a high MR ratio by improving heat resistance while maintaining a thin film of a Ru layer used as a non-magnetic layer so that the Ru layer expresses preferable exchange coupling magnetic field even through annealing at high temperature. In the tunnel magnetoresistive thin film, at least one of a first pinned magnetic layer and a second pinned magnetic layer that are layered having the non-magnetic layer for exchange coupling therebetween has a layered structure of two or more layers made of magnetic materials different from each other.

Abstract: A method of production of a magnetoresistance effect device is able to prevent or minimize a drop in the MR ratio and maintain the high performance of the magnetoresistance effect device even if forming an oxide layer as a surface-most layer constituting a protective layer by the oxidation process inevitably included in the process of production of microprocessing by dry etching performed in a vacuum. Two mask layers used for microprocessing are doubly piled up. This method of production of a magnetoresistivity effect device including a magnetic multilayer film including at least two magnetic layers includes a step of providing under a first mask material that is a nonorganic material a second mask material able to react with other atoms to form a conductive substance, and a device made according to the method.

Abstract: A dynamic fly heater (DFH) for improved lifetime and better film uniformity is disclosed for a magnetic head. The heater has a lower amorphous Ta layer and an upper W layer to promote small grain size and reduced electro-migration. The composite film is especially advantageous for heaters greater than 1000 Angstroms thick where dR/R is difficult to control in the prior art. The DFH may be a (Ta/W)n laminate in which the Ta layers are about 30 Angstroms thick and the combined thickness of the W layers is from 400 to 1200 Angstroms. A Ta film is preferably sputter deposited with an Ar pressure of 3 to 5 mTorr and the W film is sputter deposited in the same chamber with a 3 to 20 mTorr Ar pressure. In one embodiment, a merged read/write head has one DFH in the read head and a second DFH in the write head.

Abstract: A magneto-resistive (MR) device for reading at least one of a legacy data signal and a present data signal magnetically recorded on at least one legacy track and a least one present track, respectively, is provided. The device comprises first and second MR elements, and first, second, and third permanent magnets. The first MR read element is positioned between the first and the second permanent magnets to stabilize the first MR read element while reading the legacy data signal from the media. The second MR element is positioned adjacent to the second permanent magnet and configured to read the present data signal from the media. The third permanent magnet is positioned adjacent to the second MR element and opposite to the second permanent magnet. The second and the third permanent magnets cooperate with each other to stabilize the second MR read element while reading the present data signal from the media.

Abstract: An oscillator includes at least one of: (i) a parallel array of resistors (420, 421, 422, 701, 801, 901, 902) or magnetoresistive contacts to a magnetoresistive film (120, 320); and (ii) a series array of resistors (620, 621, 702, 902) or magnetoresistive contacts to individualized areas of at least one magnetoresistive film.

Abstract: EMR elements and methods of fabricating the EMR elements are disclosed. The EMR structure includes one or more layers that form an active region, such as a two-dimensional electron gas (2DEG). The EMR structure has a first side surface, having a plurality of lead protrusions that extend outwardly from the main body of the EMR structure, and an opposing second side surface. The lead protrusions are used to form the current and voltage leads for the EMR element. The active region extends through each lead protrusion and is accessible along a perimeter of each of the lead protrusions. Conductive material is formed along the perimeter of each lead protrusion and contacts the active region of the EMR structure along the perimeter. The lead protrusion and the corresponding conductive material contacting the active region of each lead protrusion form leads for the EMR element, such as current leads and voltage leads.

Abstract: A magnetoresistance device has a channel extending between first and second ends in a first direction comprising non-ferromagnetic semiconducting material, such as silicon, a plurality of leads connected to and spaced apart along the channel, a gate structure for applying an electric field to the channel in a second direction which is substantially perpendicular to the first direction so as to form an inversion layer in the channel and a face which lies substantially in a plane defined by the first and second directions and which is configured such that an edge of the channel runs along the face.

Abstract: A device capable of exhibiting the extraordinary magnetoresistance (EMR) effect includes an elongate channel formed of silicon. A conductor comprising heavily doped silicon is connected to the channel along one side of the channel so as to provide a shunt. A gate arrangement including a gate electrode is provided on the channel. Applying a bias of appropriate polarity and sufficient magnitude to the gate electrode results in the formation of an inversion layer in the channel.

Abstract: An apparatus and method for determining a resistance of a magneto-resistive head. A current drawn by the head, in response to a fixed bias voltage across the head, is converted to a zero temperature coefficient current such that when supplied to a resistor connected to an input terminal of a comparator the effects of variations in the resistance value are avoided. An output signal of the comparator indicates the resistance of the magneto-resistive head.

Abstract: The invention provides a magnetoresistive device of the CPP (current perpendicular to plane) structure, comprising a magnetoresistive unit, and a first, substantially soft magnetic shield layer positioned below and a second, substantially soft magnetic shield layer positioned above, which are located and formed such that the magnetoresistive effect is sandwiched between them from above and below, with a sense current applied in the stacking direction. The magnetoresistive unit comprises a nonmagnetic 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. At least one of the first shield layer positioned below and the second shield layer positioned above is configured in a framework form having a planar shape (X-Y plane) defined by the width and length directions of the device.

Abstract: The magnetic head having shielding layers is capable of preventing fluctuation of output caused by magnetic domain structures of the shielding layers, stabilizing the output, restraining variation of products and improving production yield. The magnetic head comprises: shielding layers for magnetically shielding a magnetoresistance effect reproducing element; hard films being located on the both sides of the magnetoresistance effect reproducing element as seen from a facing surface which faces a recording medium; and soft magnetic layers being composed of a soft magnetic material, the soft magnetic layers being located on the both sides of the shielding layers as seen from the facing surface.