Abstract: A dual antiparallel (AP) spin valve sensor has first, second, third and fourth AP pinned layers which are pinned by sense current fields from a sense current. First and second pinning layers are omitted so that the sensor stack has a reduced height for increasing the linear read bit density of a magnetic read head. Ferromagnetic coupling fields caused by second and third AP pinned layers next to a free layer structure are counterbalanced by a net demagnetizing field from the first and second AP pinned layer structures.

Abstract: A triple antiparallel (AP) coupled free layer structure is located between first and second pinned layer structures in a dual spin valve sensor. The triple AP coupled free layer structure includes first, second and third antiparallel (AP) coupled ferromagnetic free layers and nonmagnetic first and second antiparallel (AP) coupling layers. The first AP coupling layer is located between and interfaces the first and second AP coupled free layers and the second AP coupling layer is located between and interfaces the second and third AP coupled free layers. Magnetic moments of the first and third AP coupled free layers are parallel with respect to one another and, because of a strong antiparallel coupling, the second AP coupled free layer pins magnetic moments of the first and third AP coupled free layers antiparallel thereto.

Abstract: A giant magnetoresistive stack for use in a magnetic read head has a plurality of layers including at least one ferromagnetic layer which contributes to a giant magnetoresistive signal, and at least one doped ferromagnetic layer which does not contribute to a giant magnetoresistive signal. The dopant in the doped ferromagnetic layer reduces parasitic shunting current through the giant magnetoresistive stack by providing an increase in resistivity without a decrease in magnetization.

Abstract: A dual spin valve read head includes first and second spin valve stacks configured to operate in a current perpendicular to plane (CPP) mode. The first and the second spin valve stacks each include a free layer. A spacer is positioned adjacent the free layers of the first and the second spin valve stacks and spaces the first spin valve stack apart from the second spin valve stack.

Abstract: A spin valve thin-film magnetic device is provided, in which the asymmetry can be reduced. The spin valve thin-film magnetic device comprises a free magnetic layer and a first and a second fixed magnetic layer, which are provided respectively at each side of the free magnetic layer in the thickness direction thereof. In the spin valve thin-film magnetic device, the free magnetic layer is composed of a first and a second ferromagnetic free layer, in which the entire free magnetic layer is in a ferrimagnetic state, the first fixed magnetic layer is composed of a first and a second pinned ferromagnetic layer, in which the entire first fixed magnetic layer is in a ferrimagnetic state, and the second fixed magnetic layer is composed of a third and a fourth pinned ferromagnetic layer, in which the entire second fixed magnetic layer is in a ferrimagnetic state.

Abstract: A magnetoresistive element has a ferromagnetic double tunnel junction having a stacked structure of a first antiferromagnetic layer/a first ferromagnetic layer/a first dielectric layer/a second ferromagnetic layer/a second dielectric layer/a third ferromagnetic layer/a second antiferromagnetic layer. The second ferromagnetic layer that is a free layer consists of a Co-based alloy or a three-layered film of a Co-based alloy/a Ni—Fe alloy/a Co-based alloy. A tunnel current is flowed between the first ferromagnetic layer and the third ferromagnetic layer.

Abstract: A magnetic transducer (head) according to the invention includes a free layer structure comprising two free layers exchange coupled across a thin spacer structure of comprising two spacer layers of nonmagnetic material separated by a ferromagnetic nano-oxide layer (NOL). The spacer layers prevent the NOL from unnecessarily hardening the free layer(s). The spacer layers are preferably copper or copper oxide. The spacer layers preserve the NOL's property of specular scattering of conduction electrons which tends to increase the magnetoresistive response. A free layer structure including the exchange coupling spacer structure of the invention can be used in a dual spin valve configuration, but is also useful in a single spin valve configuration. The free layer of the invention is useful in conduction in-plane (CIP), as well as, conduction perpendicular to the plane (CPP) devices.

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

Abstract: A dual tunnel junction sensor operates without the requirement of first and second shield layers. This is accomplished by making first and second free layer structures antiparallel (AP) coupled structures. The first free layer structure has first and second AP coupled layers and the second free layer structure has third and fourth AP coupled layers. The thicknesses of the first and third AP coupled layers, which are preferably equal, are different from the thicknesses of the second and fourth AP coupled layers, which are also preferably equal. Field signals from perpendicular or longitudinally recorded magnetic disks rotate the magnetic moments of the first and second free layer structures so that resistances on each side of a pinning layer are additive. Extraneous field signals, other than signal fields from the rotating magnetic disk, are cancelled by common mode rejection.

Abstract: A dual magnetic tunnel junction (MTJ) sensor is provided with a longitudinal bias stack sandwiched between a first MTJ stack and a second MTJ stack. The longitudinal bias stack comprises an antiferromagnetic (AFM) layer sandwiched between first and second ferromagnetic layers. The first and second MTJ stacks comprise antiparallel (AP)-pinned layers pinned by AFM layers made of an AFM material having a higher blocking temperature than the AFM material of the bias stack allowing the AP-pinned layers to be pinned in a transverse direction and the bias stack to be pinned in a longitudinal direction. The demagnetizing fields of the two AP-pinned layers cancel each other and the bias stack provides flux closures for the sense layers of the first and second MTJ stacks.

Abstract: A dual spin valve (SV) sensor is provided with a longitudinal bias stack sandwiched between a first SV stack and a second SV stack. The longitudinal bias stack comprises an antiferromagnetic (AFM) layer sandwiched between first and second ferromagnetic layers. The first and second SV stacks comprise antiparallel (AP)-pinned layers pinned by AFM layers made of an AFM material having a higher blocking temperature than the AFM material of the bias stack allowing the AP-pinned layers to be pinned in a transverse direction and the bias stack to be pinned in a longitudinal direction. The demagnetizing fields of the two AP-pinned layers cancel each other and the bias stack provides flux closures for the sense layers of the first and second SV stacks.

Abstract: A dual spin-valve magnetoresistive thin film element includes a free magnetic layer, first and second nonmagnetic electrically conductive layers residing below and above the composite free magnetic layer, respectively, first and second dual pinned magnetic layers each having first and second pinned magnetic layers, and first and second antiferromagnetic layers. In the first dual pinned magnetic layer, the first pinned magnetic layer of contacts the first antiferromagnetic layer and the second pinned magnetic layer contacts the first nonmagnetic electrically conductive layer. In the second dual pinned magnetic layer, the first pinned magnetic layer of contacts the second antiferromagnetic layer and the second pinned magnetic layer contacts the second nonmagnetic electrically conductive layer, and the magnetic moment of the first pinned magnetic layer is greater than the second pinned magnetic layer.

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 dual spin valve sensor is provided with a triple AP pinned layer structure on one side of a free layer and a single pinned layer on an opposite side of the free layer for increasing the flexibility in properly biasing the magnetic moment of the free layer. In one embodiment a negative ferromagnetic coupling field may be provided for still further increasing the flexibility of biasing the free layer. In another embodiment the triple AP pinned layer structure may be provided with no demagnetizing field and in still a further embodiment the triple AP pinned layer structure may be provided with a demagnetizing field as desired for still further increasing the flexibility in biasing the free layer.

Abstract: An integrated read/write perpendicular recording head facilitates the use of magnetic storage media having a high magnetic recording density and high data rates. The use of a perpendicular write portion provides adequate space between the main and opposing poles for a read element and associated electrical contacts therebetween. The use of a differential dual spin valve as a read element eliminates the need for magnetic shielding of the read element. Such a structure permits the read element and main write pole to be close together, thereby minimizing seek time, and permitting rapid transition from read to write operations, and vice versa.

Abstract: A dual spin-valve magnetoresistive thin film elements includes a free magnetic layer, first and second nonmagnetic electrically conductive layers residing below and above the composite free magnetic layer, respectively, first and second dual pinned magnetic layers each having first and second pinned magnetic layers, and first and second antiferromagnetic layers. In the first dual pinned magnetic layer, the first pinned magnetic layer of contacts the first antiferromagnetic layer and the second pinned magnetic layer contacts the first nonmagnetic electrically conductive layer. In the second dual pinned magnetic layer, the first pinned magnetic layer of contacts the second antiferromagnetic layer and the second pinned magnetic layer contacts the second nonmagnetic electrically conductive layer, and the magnetic moment of the first pinned magnetic layer is greater than the second pinned magnetic layer.

Abstract: In the method of making a thin-film magnetic head in accordance with the present invention, an electron beam resist is irradiated with electron beams in a state where an electrically conductive member is in contact with a magnetoresistive film. Since the magnetoresistive film electrically connects individual forming positions to be formed with magnetoresistive devices, charges stored near the forming positions upon irradiation with the electron beams can be drawn to the outside by way of the electrically conductive member. As a consequence, the electron beams are less likely to lose their rectilinearity, whereby the writing precision for patterning the magnetoresistive film by electron beam lithography can be improved.

Abstract: A dual spin-valve magnetoresistive thin film elements includes a composite free magnetic layer having first and second free magnetic layers, first and second nonmagnetic electrically conductive layers residing below and above the composite free magnetic layer, respectively, first and second dual pinned magnetic layers each having first and second pinned magnetic layers, and first and second antiferromagnetic layers. In the first dual pinned magnetic layer, the first pinned magnetic layer of contacts the first antiferromagnetic layer and the second pinned magnetic layer contacts the first nonmagnetic electrically conductive layer. In the second dual pinned magnetic layer, the first pinned magnetic layer of contacts the second antiferromagnetic layer and the second pinned magnetic layer contacts the second nonmagnetic electrically conductive layer, and the magnetic moment of the first pinned magnetic layer is smaller than the second pinned magnetic layer.

Abstract: A thin-film magnetic head provided with a magnetoresistive thin-film element includes a laminate including an antiferromagnetic layer, a pinned magnetic layer, a nonmagnetic conductive layer, and a free magnetic layer. At both sides of the laminate, soft magnetic layers, secondary antiferromagnetic layers, and conductive layers are formed. The antiferromagnetic layer generates a unidirectional exchange coupling by heat treatment to fix the magnetization of the pinned magnetic layer, and the secondary antiferromagnetic layers generate a unidirectional exchange coupling as deposited without heat treatment.

Abstract: A dual antiparallel (AP) pinned spin valve sensor has a free layer which is biased by opposite ferromagnetic coupling fields and opposite demagnetizing fields from first and second AP pinned layer structures. The opposite magnetic coupling fields are obtained by appropriately sizing first and second spacer layers of the sensor and the opposite demagnetizing fields are obtained by appropriately sizing first and second AP pinned layers of a first AP pinned layer structure and appropriately sizing third and fourth AP pinned layers of a second AP pinned layer structure.

Abstract: First and second magneto-resistive effect elements (1) and (2) of a current perpendicular to plane type having magnetic flux sensing films are laminated through a nonmagnetic intermediate gap layer (3) in such a manner that their magnetic flux sensing films are located close to each other. Then, magneto-resistive change characteristics are caused to become opposite to each other so that a differential output between the output of the first and second magneto-resistive effect elements may be generated as a magnetic sensor output or a differential output between the output of the first and second magneto-resistive effect elements may be generated as a differential output in an external circuit configuration. In this manner, a resolution can be improved by a configuration in which a gap length, which decides a resolution, may not be restricted by a thickness of a magneto-resistive effect element. Therefore, restrictions imposed on the resolution in the MR magnetic sensor can be improved.

Abstract: A pinned layer structure includes a nickel iron (NiFe) film which lowers the coercivity HC of the pinned layer structure as well as the coercivity HC of a free layer structure within a spin valve sensor, thereby promoting return of a magnetic moment of the pinned layer structure to its original orientation after being rotated therefrom and promoting a freer rotation of the magnetic moment of the free layer structure in response to signal fields from a rotating magnetic disk. In a preferred embodiment the pinned layer structure is an antiparallel (AP) pinned layer structure which has an antiparallel coupling layer located between first and second AP pinned layers.

Abstract: A dual spin-valve magnetoresistive thin film elements includes a composite free magnetic layer having first and second free magnetic layers, first and second nonmagnetic electrically conductive layers residing below and above the composite free magnetic layer, respectively, first and second dual pinned magnetic layers each having first and second pinned magnetic layers, and first and second antiferromagnetic layers. In the first dual pinned magnetic layer, the first pinned magnetic layer of contacts the first antiferromagnetic layer and the second pinned magnetic layer contacts the first nonmagnetic electrically conductive layer. In the second dual pinned magnetic layer, the first pinned magnetic layer of contacts the second antiferromagnetic layer and the second pinned magnetic layer contacts the second nonmagnetic electrically conductive layer, and the magnetic moment of the first pinned magnetic layer is smaller than the second pinned magnetic layer.

Abstract: A read head, which has an air bearing surface (ABS), includes a yoke which has first and second legs which are interconnected at a location within the head at a distance d1 from the ABS wherein the first and second legs have first and second end edges respectively which are located at the ABS and spaced apart by a distance d2. The first and second legs have first and second separations respectively which are located between the ABS and the distance d1 and which magnetically and electrically disconnect leg portions of each leg. The first sensor is magnetically and electrically connected to the first leg across a first separation and a second sensor is magnetically and electrically connected to the second leg across the second separation. The first sensor has a first pinned layer structure and the second sensor has a second pinned layer structure wherein the first and second pinned layer structures have first and second magnetic moments respectively that are antiparallel with respect to each other.

Abstract: A Vertical Giant Magnetoresistive Sensor (VGMR) with two VGMR structures (61 A, 61 B), each responding differently to an external magnetic field, producing a differential signal proportional to the field. The magnetizations (M1, M1′, M2, M2′) in each of the sensors are oriented antiparallel. The antiparallel magnetization is attained by altering the magnetic compositions of the two structures, or adding an additional structure such as a permanent magnet or current strip (11) between the VGMR structures.

Abstract: A dual antiparallel (AP) pinned layer spin valve is provided for a read head wherein a sense current field opposes net ferromagnetic and demagnetizing fields from the first and second AP pinned layers on a free layer structure. In one embodiment the first and second AP pinned layers may be asymmetrical on each side of a free layer structure for providing a desired sense current field while in another embodiment one of the pinning layers may be insulative while the other is conductive so that the conductive pinning layer provides the necessary sense current field for counterbalancing the net ferromagnetic coupling and demagnetizing fields.

Abstract: A production method of the present invention is a method of producing a spin valve type giant magnetoresistive thin film. In this production method, a buffer layer, an antiferromagnetic layer, a fixed magnetization layer, a nonmagnetic conductive layer, a free magnetization layer, and a protective layer are consecutively stacked on a substrate. Furter, plasma treatment is performed on predetermined stacked interfaces in the spin valve type giant magnetoresistive thin film to reduce the interlayer coupling magnetic field acting between the fixed magnetization layer and the free magnetization layer and to obtain a high MR ratio. The above production method can achieve both of the high MR ratio and low interlayer coupling magnetic field (Hin) in the thin film produced.

Abstract: A method of forming a thin film magnetic head, including forming a first magnetic layer, forming a second magnetic layer as a magnetic flux passage in combination with the first magnetic layer, and forming a laminate structure body between the first magnetic layer and the second magnetic layer. The forming of the laminate structure body includes forming a third magnetic layer, a fourth magnetic layer and a non-magnetic conductive layer between the third magnetic layer and the fourth magnetic layer, projecting the laminate structure body more toward an air bearing surface than a projection of the first magnetic layer and the second magnetic layer toward the air bearing surface, and providing the laminate structure body with a width which is smaller than a width of the first magnetic layer and the second magnetic layer.

Abstract: Within a method for forming a magnetoresistive (MR) sensor element there is first provided a substrate. There is then formed over the substrate a first magnetoresistive (MR) layer having formed contacting the first magnetoresistive (MR) layer a magnetically biased first magnetic bias layer biased in a first magnetic bias direction with a first magnetic bias field strength. There is also formed separated from the first magnetoresistive (MR) layer by a spacer layer a second magnetoresistive (MR) layer having formed contacting the second magnetoresistive (MR) layer a magnetically un-biased second magnetic bias layer.

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 (&Dgr;R/R) can be improved.

Abstract: A spin-valve thin-film element includes a substrate, an antiferromagnetic layer formed on the substrate, a pinned magnetic layer formed on the antiferromagnetic layer, a nonmagnetic conductive layer formed on the pinned magnetic layer, a free magnetic layer formed on the nonmagnetic conductive layer, a hard biasing layer, a conductive layer for supplying a detecting current to the pinned magnetic layer, the nonmagnetic conductive layer, and the free magnetic layer, a biasing conductive layer for controlling the direction of a variable magnetization of the free magnetic layer, and a current supply unit for supplying a current to the conductive layer and the biasing conductive layer. The current applied to the biasing conductive layer forms a current magnetic field for controlling the direction of the variable magnetization of the free magnetic layer. The spin-valve thin-film element exhibits high heat resistance, high reliability, and small asymmetry.

Abstract: A dual spin valve magnetoresistive structure having a free layer and a spacer layer between the free layer and a pinned layer. The pinned layer is between the spacer layer and the antiferromagnetic layer. There is also an offset layer, where the antiferromagnetic layer is between the offset layer and the pinned layer. The offset layer is tailored to introduce a first magnetic field that reduces a net magnetic field within said free layer.

Abstract: A magnetic transducer (head) according to the invention includes a free layer structure comprising two free layers exchange coupled across a thin spacer structure of comprising two spacer layers of nonmagnetic material separated by a ferromagnetic nano-oxide layer (NOL). The spacer layers prevent the NOL from unnecessarily hardening the free layer(s). The spacer layers are preferably copper or copper oxide. The spacer layers preserve the NOL's property of specular scattering of conduction electrons which tends to increase the magnetoresistive response. A free layer structure including the exchange coupling spacer structure of the invention can be used in a dual spin valve configuration, but is also useful in a single spin valve configuration. The free layer of the invention is useful in conduction in-plane (CIP), as well as, conduction perpendicular to the plane (CPP) devices.

Abstract: A dual/differential spin valve (SV) sensor is provided with a single antiferromagnetic (AFM) layer sandwiched bewteen a first spin valve (SV) structure with an antiparallel (AP)-pinned layer and a second SV structure with a simple pinned layer. Having an AP-pinned layer for the first SV structure and a simple pinned layer for the second SV structure leads to a 180° phase difference in the response of the two SV structures. By arranging the bit transition length to be equal to the spacing between the free layers of the two SV structures, the signals generated by the two SV sensors are additive for both longitudinal and perpendicular recording applications.

Abstract: Apparatus and methods for reducing the sensitivity of spin valve sensor read heads for magnetic tape applications are provided. The apparatus and methods compromise the large output gain derived from using state of the art spin valve sensors in order to reduce the flux capture and thus, the signal distortion in the spin valve sensor. In order to provide a reduced sensitivity spin valve sensor, one or more of the basic sensitivity of the spin valve, the flux carrying capability of the free layer, and the flux injection efficiency of the spin valve head structure are modified to reduce the flux capture by the sensing layer.

Abstract: Apparatus and methods for reducing the sensitivity of spin valve sensor read heads for magnetic tape applications are provided. The apparatus and methods compromise the large output gain derived from using state of the art spin valve sensors in order to reduce the flux capture and thus, the signal distortion in the spin valve sensor. In order to provide a reduced sensitivity spin valve sensor, one or more of the basic sensitivity of the spin valve, the flux carrying capability of the free layer, and the flux injection efficiency of the spin valve head structure are modified to reduce the flux capture by the sensing layer.

Abstract: Apparatus and methods for reducing the sensitivity of spin valve sensor read heads for magnetic tape applications are provided. The apparatus and methods compromise the large output gain derived from using state of the art spin valve sensors in order to reduce the flux capture and thus, the signal distortion in the spin valve sensor. In order to provide a reduced sensitivity spin valve sensor, one or more of the basic sensitivity of the spin valve, the flux carrying capability of the free layer, and the flux injection efficiency of the spin valve head structure are modified to reduce the flux capture by the sensing layer.

Abstract: A spin valve magnetic head which can offer high output and stable operation is proposed.

Abstract: A method is described comprising forming an insulating polycrystalline seed layer in a first chamber by reactively pulsed DC magnetron sputtering, then forming an insulating amorphous-like seed layer in a second chamber by reactively pulsed DC magnetron sputtering, then forming a conducting seed layer and a ferromagnetic free layer in a third chamber by ion beam sputtering, and then forming the remainder of a spin valve sensor through the antiferromagnetic layer in a fourth chamber by DC magnetron sputtering.

Abstract: A dual spin valve sensor has a ferromagnetic free layer which is located between nonmagnetic first and second spacer layers wherein the first and second spacer layers are located between ferromagnetic first and second AP pinned layer structures and wherein the first and second AP pinned layer structures are located between and are exchange coupled to antiferromagnetic first and second pinning layers. In one aspect of the invention the free layer is composed of cobalt iron nickel (CoFeNi) for raising the resistance of the sensor and in another aspect of the invention first and second AP pinned layers in each of the first and second AP pinned layer structures are composed of cobalt iron (Co50Fe50) for further raising the resistance of the sensor to the sense current. The increase in the resistance of the sensor to the sense current increases the output signal of the sensor.

Abstract: In a CPP-type magnetic sensing element, a free magnetic layer includes at least two magnetic sublayers and an intermediate sublayer placed between the two adjacent magnetic sublayers, and thus the free magnetic layer is in a synthetic ferrimagnetic state. Since the physical thickness of the free magnetic layer can be increased and the resultant magnetic moment can be decreased, the bulk scattering effect is satisfactorily displayed and the magnetization of the free magnetic layer varies satisfactorily in response to en external magnetic field, resulting in an increase in the read output.

Abstract: A dual antiparallel (AP) spin valve sensor has first, second, third and fourth AP pinned layers which are pinned by sense current fields from a sense current. First and second pinning layers are omitted so that the sensor stack has a reduced height for increasing the linear read bit density of a magnetic read head. Ferromagnetic coupling fields caused by second and third AP pinned layers next to a free layer structure are counterbalanced by a net demagnetizing field from the first and second AP pinned layer structures.

Abstract: A dual hybrid magnetic tunnel junction (MTJ)/giant magnetoresistance (GMR) sensor is provided having an MTJ stack, a GMR stack and a common free layer. The MTJ stack includes a first antiferromagnetic (AFM) layer, an first antiparallel (AP)-pinned layer and a tunnel barrier layer. The GMR stack, operating in the current perpendicular to the plane (CPP) mode, includes a second AFM layer, a second AP-pinned layer and a spacer layer. The first and second AFM layers are set to pin the magnetizations of the first and second AP-pinned layers perpendicular to the ABS and in the same direction with respect to each other resulting in an additive response to a signal field of the MTJ and GMR stacks. The thickness of the spacer layer in the GMR stack is chosen to provide a negative ferromagnetic coupling field between the second AP-pinned layer and the free layer which opposes the positive ferromagnetic coupling field between the first AP-pinned layer and the free layer across the tunnel barrier layer.

Abstract: It is the object of the invention to provide a magnetic head and a magnetic storage apparatus using the magnetic head provided with a signal reproducing means which is capable of using the same signal processing circuit as used for the conventional longitudinal magnetization film type recording medium even when a perpendicular magnetization film type recording medium is used. Because the present invention renders the reproducing signal generated from a perpendicular magnetization film Gaussian shaped (Lorentzian pulse), the same signal processing circuit as used for the conventional longitudinal magnetization film type recording medium can be used.

Abstract: A dual tunnel junction sensor operates without the requirement of first and second shield layers. This is accomplished by making first and second free layer structures antiparallel (AP) coupled structures. The first free layer structure has first and second AP coupled layers and the second free layer structure has third and fourth AP coupled layers. The thicknesses of the first and third AP coupled layers, which are preferably equal, are different from the thicknesses of the second and fourth AP coupled layers, which are also preferably equal. Field signals from perpendicular or longitudinally recorded magnetic disks rotate the magnetic moments of the first and second free layer structures so that resistances on each side of a pinning layer are additive. Extraneous field signals, other than signal fields from the rotating magnetic disk, are cancelled by common mode rejection.

Abstract: A half metallic phase iron oxide (Fe3O4) layer is employed in either or both of a pinned layer structure and a free layer structure in a spin valve sensor for filtering minority electrons and reflecting majority electrons with respect to a spin scattering region for increasing the magnetoresistive coefficient dr/R of a spin valve sensor.

Abstract: An improved process for manufacturing a spin valve structure that has buried leads is disclosed. A key feature is the inclusion in the process of a temporary protective layer over the seed layer on which the spin valve structure will be grown. This protective layer remains in place while the buried leads as well as longitudinal bias means are formed. Processing includes use of photoresist liftoff. The protective layer is removed as a natural byproduct of surface cleanup just prior the formation of the spin valve.

Abstract: The invention includes methods of manufacturing improved spin valve sensors and the resulting sensors. The method includes the step of depositing a spacer layer in an environment containing oxygen. Preferably, the spacer layer is deposited in an environment containing argon and from about 0.5 to 25,000 ppm oxygen. Spin valve sensors of the invention have a spacer layer containing a non-magnetic electrically conductive material and oxygen. Spin valve sensors of the invention can be dual spin valves, bottom pinned spin valves or top pinned spin valves.

Abstract: A tunnel junction MR head can be easily manufactured and arranged as follow. A first tunnel junction is formed by a magnetization free layer, a first magnetization pinned layer and a thin insulated layer formed between the both layers. A second tunnel junction is formed by the magnetization free layer, a second magnetization pinned layer and an insulated layer. The first and second tunnel junctions are connected to both ends of the magnetization free layer through the magnetization free layer. A detection current flowing from a first electrode connected to the first tunnel junction is passed to a second electrode through the first tunnel junction, the magnetization free layer and the second tunnel junction.

Abstract: An object of the present invention is to provide a differential detection read sensor for perpendicular magnetic recording using two magnetic resistance elements; and to provide a thin film head for perpendicular recording using the read sensor and a magnetic recording apparatus having high recording density equipped with the head. The object of the present invention can be achieved by a reproducing sensor comprising a pair of magnetic resistance layers; a non-magnetic conductive layer; a pair of conductive layers; and a pair of magnetic shields.