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Kei Hirata, Tokyo JP

Kei Hirata, Tokyo JP

Patent application numberDescriptionPublished
20080204938Thin-Film Magnetic Head Having Antistatic Means for Protective Coat of Element End - Provided is a thin-film magnetic head in which a noise due to the voltage potential difference between the read head element and the protective coat surface is suppressed. The thin-film magnetic head comprises: a read head element, one end surface of the read head element reaching an head end surface on the ABS side; a protective coat formed on the head end surface in such a way to cover at least the one end surface of the read head element; and at least one antistatic means for preventing the protective coat from being electrostatically charged, formed on/above the element formation surface, one end surface of the at least one antistatic means reaching the head end surface, the protective coat covering a portion, not the whole, of the one end surface of the at least one antistatic means on the head end surface.08-28-2008
20080218907MAGNETO-RESISTANCE EFFECT ELEMENT AND THIN-FILM MAGNETIC HEAD - A magneto-resistance effect element (MR element) used for a thin film magnetic head is configured by a buffer layer, an anti-ferromagnetic layer, a pinned layer, a spacer layer, a free layer, and a cap layer, which are laminated in this order, and a sense current flows through the element in a direction orthogonal to the layer surface, via a lower shield layer and a upper shield layer. The pinned layer comprises an outer layer in which a magnetization direction is fixed, a non-magnetic intermediate layer, and an inner layer which is a ferromagnetic layer. The spacer layer comprises a first non-magnetic metal layer, a semiconductor layer, and a second non-magnetic metal layer. The first non-magnetic metal layer and the second non-magnetic metal layer comprise CuPt films having a thickness ranging from a minimum of 0.2 nm to a maximum of 2.0 nm, and the Pt content ranges from a minimum of 5 at % to a maximum of 25 at %. The semiconductor layer comprises a ZnO film, ZnS film, or GaN film having a thickness ranging from a minimum of 1.0 nm to a maximum of 2.5 nm.09-11-2008
20080218912CPP-type magnetoresistive element having spacer layer that includes semiconductor layer - An MR element includes: a free layer whose direction of magnetization changes in response to a signal magnetic field; a pinned layer whose direction of magnetization is fixed; and a spacer layer disposed between these layers. The spacer layer includes: a semiconductor layer made of an n-type semiconductor; and a Schottky barrier forming layer made of a metal material having a work function higher than that of the n-type semiconductor that the semiconductor layer is made of, the Schottky barrier forming layer being disposed in at least one of a position between the semiconductor layer and the free layer and a position between the semiconductor layer and the pinned layer, touching the semiconductor layer and forming a Schottky barrier at an interface between the semiconductor layer and itself The semiconductor layer is 1.1 to 1.7 nm in thickness, and the Schottky barrier forming layer is 0.1 to 0.3 nm in thickness.09-11-2008
20080218915Tunnel Magnetoresistive Effect Element With Lower Noise and Thin-Film Magnet Head Having the Element - Provided is a TMR effect element having no special structures needing much man-hour cost for the formation, in which the high temperature noise and the low temperature noise are suppressed and a sufficiently high resistance-change ratio is provided. The TMR effect element comprises: a tunnel barrier layer formed by oxidizing a base film; and two ferromagnetic layers stacked so as to sandwich the tunnel barrier layer, the base film having a film thickness larger than a film thickness at which a resistance-change ratio of the TMR effect element indicates a maximum value. Here, in the case that the base film is an aluminum film, the film thickness of the aluminum film is preferably in the range of 0.50 nm to 1.5 nm.09-11-2008
20080226947MAGNETO-RESISTANCE EFFECT ELEMENT HAVING FREE LAYER INCLUDING MAGNETOSTRICTION REDUCTION LAYER AND THIN-FILM MAGNETIC HEAD - A magnetoresistance effect element includes a pinned layer having a fixed magnetization direction, a free layer having a magnetization direction variable depending on an external magnetic field, and a nonmagnetic spacer layer disposed between the pinned layer and the free layer. The free layer includes a Heusler alloy layer and a magnetostriction reduction layer made of a 4th group element, a 5th group element, or a 6th group element.09-18-2008
20080226948MAGNETO-RESISTANCE EFFECT ELEMENT HAVING DIFFUSION BLOCKING LAYER AND THIN-FILM MAGNETIC HEAD - A magnetoresistance effect element (MR element) for use in a thin-film magnetic head has a buffer layer, an antiferromagnetic layer, a pinned layer, a spacer layer, a free layer, and a cap layer that are successively stacked. A sense current flows in a direction perpendicular to layer surfaces via a lower shield layer and an upper shield layer. The pinned layer comprises an outer layer having a fixed magnetization direction, a nonmagnetic intermediate layer, and an inner layer in the form of a ferromagnetic layer. The spacer layer comprises a first nonmagnetic metal layer, a semiconductor layer made of ZnO, and a second nonmagnetic metal layer. The inner layer or the outer layer includes a diffusion blocking layer made of an oxide of an element whose electronegativity is equal to or smaller than Zn, e.g., ZnO, TaO, ZrO, MgO, TiO, or HfO, or made of RuO.09-18-2008
20080291582Thin film magnetic head, head gimbal assembly, head arm assembly and magnetic disk device - Provided is a thin film magnetic head capable of suppressing an occurrence of a track erase, decreasing an influence on a magnetoresistive element caused by a magnetic flux generated from a thin film coil, and further decreasing the parasitic capacity. The thin film magnetic head has, in order in a stacked direction, a first magnetic shield layer, a magnetoresistive element, a second magnetic shield layer, a third magnetic shield layer, a main magnetic pole layer and a return yoke layer. A width in a track width direction of at least one of the first and the second magnetic shield layers is smaller than widths in a track width direction of the third magnetic shield layer and the return yoke layer.11-27-2008
20080305442Patterned material layer, method of forming the same, microdevice, and method of manufacturing the same - A formation method for a patterned material layer comprising a step of exposing a composite layer to light in a predetermined pattern, the composite layer including a first photosensitive resin layer, a protective film, and an upper resin layer; a step of partly removing the exposed composite layer so as to form an opening exposing the substrate and form a groove along the main surface of the substrate on a side face of the opening by depressing the end portion of the upper resin layer on the substrate side, thereby forming a resist frame comprising the composite layer formed with the opening; a step of forming a vacuum coated layer having a material pattern part formed on the substrate in the opening and a part to lift off formed on the resist frame, by vacuum coating process; and a step of removing the part to lift off together with the resist frame, so as to yield a patterned material layer.12-11-2008
20090086384MAGNETO-RESISTANCE EFFECT ELEMENT INCLUDING FERROMAGNETIC LAYER HAVING GRANULAR STRUCTURE - A magneto-resistance effect element of the present invention comprises: a pair of ferromagnetic layers whose magnetization directions change in accordance with an external magnetic field, each of the pair of ferromagnetic layers having a granular structure in which a large number of magnetic grains are distributed within a nonmagnetic matrix material; a conductive nonmagnetic intermediate layer sandwiched between the pair of ferromagnetic layers; and a bias magnetic field applying layer for exerting magnetic force on the pair of ferromagnetic layers. The matrix material in the pair of ferromagnetic layer contains conductive material. Moreover, another magneto-resistance effect element of the present invention includes: a pair of ferromagnetic layers whose magnetization directions change in accordance with an external magnetic field, each of the pair of ferromagnetic layers having a granular structure in which a large number of magnetic grains are distributed within a nonmagnetic matrix material; an insulating nonmagnetic intermediate layer sandwiched between the pair of ferromagnetic layers; and a bias magnetic field applying layer for exerting magnetic force on the pair of ferromagnetic layers. The matrix material in the pair of ferromagnetic layers contains a metallic oxide, and contains the same material as that of the insulating nonmagnetic intermediate layer.04-02-2009
20090237839CPP-TYPE MAGNETORESISTANCE EFFECT ELEMENT HAVING THREE MAGNETIC LAYERS - A magnetoresistance effect element comprises: a magnetoresistive stack including: first, second and third magnetic layers whose magnetization directions change in accordance with an external magnetic field, said second magnetic layer being located between said first magnetic layer and the third magnetic layer; a first non-magnetic intermediate layer sandwiched between said first and second magnetic layers, said first non-magnetic intermediate layer allowing said first magnetic layer and said second magnetic layer to be exchange-coupled such that the magnetization directions thereof are anti-parallel to each other when no magnetic field is applied; and a second non-magnetic intermediate layer sandwiched between said second and third magnetic layers, said second non-magnetic intermediate layer producing a magnetoresistance effect between said second magnetic layer and said third magnetic layer; wherein sense current is adapted to flow in a direction perpendicular to a film plane; a bias magnetic layer provided on an opposite side of said magnetoresistive stack from an air bearing surface, said bias magnetic layer applying a bias magnetic field to said magnetoresistive stack in a direction perpendicular to the air bearing surface.09-24-2009
20090273864Magnetoresistive element including two ferromagnetic layers - A magnetoresistive element includes a first and a second shield, and an MR stack disposed between the shields. The MR stack includes a first and a second ferromagnetic layer, and a nonmagnetic spacer layer disposed between the ferromagnetic layers. The first and second ferromagnetic layers have magnetizations that are in directions antiparallel to each other when no external magnetic field is applied to the layers, and that change directions in response to an external magnetic field. An insulating layer is formed to touch a rear end face of the MR stack and the first shield, and a bias magnetic field applying layer is formed above the insulating layer with a buffer layer disposed in between. The bias magnetic field applying layer includes a hard magnetic layer and a high saturation magnetization layer. The high saturation magnetization layer is located between the rear end face and the hard magnetic layer, but not located between the first shield and the hard magnetic layer.11-05-2009
20090323222Thin film magnetic head, magnetic head slider, head gimbal assembly, head arm assembly, magnetic disk device and method of manufacturing thin film magnetic head - In manufacturing the thin film magnetic head, the rear end face of the MR element and the rear end face of a resistive film pattern are determined with high precision using a mask pattern, in which a first opening and a second opening are collectively formed. The first and second openings are located side by side in a track-width direction. The first opening includes a first edge extending across the MR film in the track-width direction, and the second opening includes a second edge located at a given interval, as measured in a direction orthogonal to the track-width direction, from the first edge, and extending in the track-width direction. In the step of polishing for forming a magnetic-recording-medium-facing-surface, the amount of polishing is determined by monitoring the resistance change of the resistive film pattern, thereby reducing the dimension errors in the MR height when manufacturing the MR element.12-31-2009
20100053819Thin film magnetic head, magnetic head slider, head gimbal assembly, head arm assembly, magnetic disk device and method of manufacturing thin film magnetic head - The invention is devised to provide a method of manufacturing a thin film magnetic head including a magnetoresistive element having higher reading performance. In manufacturing the thin film magnetic head, after forming an MR element 03-04-2010
20100061023MAGNETIC HEAD DEVICE AND MAGNETIC DISK DRIVE APPARATUS WITH THE MAGNETIC HEAD DEVICE - A magnetic head device includes a magnetic head section having a first free layer with a magnetization orientation that is not previously defined but changes depending upon only external magnetic field applied, a second free layer with a magnetization orientation that is not previously defined but changes depending upon only external magnetic field applied, a nonmagnetic intermediate layer sandwiched between the first free layer and the second free layer, a first electrode layer stacked on a surface of the first free layer opposite to the nonmagnetic intermediate layer, and a second electrode layer stacked on a surface of the second free layer opposite to the nonmagnetic intermediate layer; a sense-current supply means for flowing a sense current across the first electrode layer and the second electrode layer of the magnetic head section; and a frequency divider circuit for dividing by two a frequency of an output signal produced across the first electrode layer and the second electrode layer of the magnetic head section.03-11-2010
20100177440Thin film magnetic head and magnetic disk device - Foundation layers of a thin film magnetic head are disposed between insulating layers and bias magnetic field application layers, and are configured of Cr or Cr alloy. The insulating layers are configured of a Si oxide such that the Si content of the Si oxide is in the range of 30˜56 at % (atom %) and that the atom ratio of oxygen to Si (O/Si) is in the range of 0.8˜1.3. With the configuration, the occurrence rate of noise is reduced.07-15-2010
20100202088Magnetoresistive element, thin film magnetic head, magnetic head slider, head gimbal assembly, head arm assembly and magnetic disk device - The invention is devised to provide a magnetoresistive element that is hardly susceptible to harmful influence of unnecessary magnetic fields and noise of heat even when reduction in size is achieved to be adaptable to higher recording density, and therefore that is excellent in operational reliability. The magnetoresistive element includes a stacked structure including, in order: a magnetically pinned layer whose magnetization direction is fixed in a given direction; a non-magnetic layer; a magnetically free layer whose magnetization direction changes according to an external magnetic field; and an antiferromagnetic bias layer exchange-coupled with the magnetically free layer. The exchange-coupling magnetic field between the magnetically free layer and the antiferromagnetic bias layer is smaller than a saturation magnetic field of the magnetically free layer.08-12-2010
20100302680Perpendicular magnetic write head and magnetic write device - A perpendicular magnetic write head includes: a magnetic pole having an end face on an air bearing surface; and side shield layers each having an end face on the air bearing surface, and arranged on both sides, in a write track width direction, of the magnetic pole with a side gap in between. The end face of the magnetic pole has a geometry in which a width at a trailing edge is larger than a width at a leading edge. Relationship D12-02-2010
20110090595Magnetic head for perpendicular magnetic recording and method of manufacturing same - A main magnetic pole includes a first part extending from a medium facing surface to a point at a predetermined distance from the medium facing surface, and a second part other than the first part. An accommodation part for accommodating the main magnetic pole includes: a first layer having a groove; a second layer lying between the first layer and the main magnetic pole in the first layer's groove; and a third layer interposed in part between the second layer and the main magnetic pole in the first layer's groove. The second layer is formed of a metal material different from a material used to form the first layer. The third layer is formed of an inorganic insulating material. The second and third layers lie between the first layer and the first part. The second layer lies between the bottom of the first layer's groove and the second part, but the third layer does not. The distance between the bottom of the first layer's groove and the second part is smaller than that between the bottom and the first part.04-21-2011
20110157746Perpendicular magnetic recording head and magnetic recording device - A perpendicular magnetic write head includes: a magnetic pole; a pair of side shields on both sides, in a write-track width direction, of the magnetic pole with respective side gaps in between; a trailing shield on a trailing side of the magnetic pole and the pair of side shields with a trailing gap in between. Each of the magnetic pole, the side shield, the trailing shield, the side gap, and the trailing gap has an end face exposed on an air bearing surface. The trailing gap has a first regional part and a second regional part. The first regional part separates a trailing edge of the magnetic pole from the trailing shield, and the second regional part separates the pair of side shields from the trailing shield. All or a part of the second regional part has a thickness larger than a thickness of the first regional part.06-30-2011

Patent applications by Kei Hirata, Tokyo JP