Patent application number | Description | Published |
20080247097 | MAGNETORESISTANCE EFFECT ELEMENT AND MAGNETIC HEAD - A magnetoresistance effect element has a lamination structure comprising a free layer including two ferromagnetic layers, a pinned layer including two ferromagnetic layers, and at least one nano-contact portion composed of a single ferromagnetic layer and disposed at least one portion between the free layer and the pinned layer. A distance between the free layer and the pinned layer, i.e., thickness of the nano-contact portion in the lamination direction, is not more than Fermi length, preferably less than 100 nm. | 10-09-2008 |
20090009915 | FILM AND METHOD FOR PRODUCING NANO-PARTICLES FOR MAGNETORESISTIVE DEVICE - A method of generating a thin film for use in a spin valve of a magnetoresistive (MR) sensor having a nano-constricted spacer is provided. The bottom portion of the spin valve is deposited up to the pinned layer, a deposition chamber is provided, and the spacer layer is sputtered thereon. A main ion beam generates ions onto a composite surface including magnetic chips and insulator material. Simultaneously, an assisted ion beam provides ions directly to the substrate, thus improving the softness of the free layer and smoothness of the spacer layer. Neutralizers are also provided to prevent ion repulsion and improve ion beam focus. As a result, a thin film spacer can be formed, and the nano-constricted MR spin valve having low free layer coercivity and low interlayer coupling between the free layer and pinned layer is formed. | 01-08-2009 |
20090290267 | Magnetic Recording and Reproducing Apparatus with Thin-Film Magnetic Head Having Microwave Magnetic Exciting Function - A magnetic recording and reproducing apparatus with a thin-film magnetic head having microwave magnetic exciting function, includes a metal housing, a magnetic recording medium, arranged in the metal housing, having a magnetic recording layer, and a thin-film magnetic head, arranged in the metal housing, having a write magnetic field production unit and a resonance magnetic field production unit. The write magnetic field production unit produces, in response to a write signal, a write magnetic field to be applied into the magnetic recording layer, and the resonance magnetic field production unit produces, in response to a microwave excitation signal, a resonance magnetic field with a frequency equal to or in a range near a ferromagnetic resonance frequency F | 11-26-2009 |
20100073804 | Thin-Film Magnetic Head Having Microwave Magnetic Exciting Function And Magnetic Recording And Reproducing Apparatus - A thin-film magnetic head having microwave magnetic exciting function includes a write magnetic field production means for producing, in response to a write signal, a write magnetic field to be applied into a magnetic recording medium, and at least line conductor of a microwave radiator of a plane-structure type, formed independent from the write magnetic field production means, for radiating, by feeding there through a microwave excitation current, a microwave band resonance magnetic field with a frequency equal to or in a range near a ferromagnetic resonance frequency F | 03-25-2010 |
20110198253 | STORING PACKAGE UNIT AND A STORING METHOD FOR MICRO SOLDER SPHERES - An object of the present invention is to prevent “deteriorations,” such as oxidization and deformation of micro solder spheres during storage. | 08-18-2011 |
20110222185 | Magnetic Recording Apparatus Provided with Microwave-Assisted Head - A magnetic recording apparatus includes a magnetic recording medium having a magnetic recording layer, a thin-film magnetic head with a microwave-band magnetic drive function, the head having a write field generation means that generates a write field to the magnetic recording medium in response to a write signal, and a microwave generator that is provided independent of the write field generation means and generates an alternating magnetic field in plane having a microwave-band frequency when microwave-excitation current is fed, an excitation current generation means that generates the microwave-excitation current by amplitude-modulating microwave carrier current with a modulating signal having a fixed period, and a write signal supply means that generates the write signal and applies it to the write field generation means of the thin-film magnetic head. | 09-15-2011 |
20110242696 | MICROWAVE ASSISTED MAGNETIC HEAD - A gap between a main pole and auxiliary pole composing a thin film magnetic head having a microwave assisted function of the present invention is filled with a nonmagnetic dielectric layer to embed a microwave radiator. The nonmagnetic dielectric layer has an inclined surface at a end on a side of an opposing medium surface by which the microwave radiated from the microwave radiator to be bent toward the main pole, whereby the microwave magnetic field generated from the microwave generator can be gathered immediately below the main pole, further improving the microwave assisted effect. | 10-06-2011 |
20110248710 | APPARATUS FOR MEASURING MAGNETIC FIELD OF MICROWAVE-ASSISTED HEAD - A measuring circuit system in a magnetic field measuring apparatus of the invention has an amplifier and a band-pass filter connected in sequence on an output terminal side of the TMR element, the band-pass filter is a narrow-range band-pass filter such that a peak pass frequency of the filter that is a center is a basic frequency selected from a range of 10 to 40 GHz and a band width centered around the basic frequency is a narrow range of ±0.5 to ±4 GHz; and with the measuring circuit system, an SIN ratio (SNR) of 3 dB or greater is obtained, the SNR being defined by a ratio of an amplitude S of a high-frequency generated signal induced by the TMR element to a total noise N that is a sum of a head noise generated by the TMR element and a circuit noise generated by the amplifier. With such a configuration, an in-plane high-frequency magnetic field generated by a microwave-assisted magnetic head is reliably and precisely measured. | 10-13-2011 |
20120033534 | MICROWAVE ASSISTED MAGNETIC HEAD - A microwave assisted magnetic head is formed to include a main pole magnetic layer including a main pole; a shielded magnetic layer including a shielded pole; a recording coil that is formed to generate a writing magnetic field from a tip of the main pole; and a microwave radiation waveguide made of a conductive nonmagnetic material that is disposed in a recording gap, the recording gap being a gap between the main pole and the shielded pole. The main pole magnetic layer and the shielded magnetic layer have an intermediate connection part that connects the layers at a depth-side, and an electrical insulation magnetic film is disposed in the intermediate connection part, and the main pole and the shielded pole are electrically connected with the microwave radiation waveguide that is disposed in the recording gap, which is the gap between the main pole and the shielded pole so that a simple configuration, with a relatively easy and efficient manufacturing process, is realized that overlaps AC magnetic fields in an in-plane direction of a microwave band, which is the same as, or close to, a ferromagnetic resonant frequency of a medium recording layer. | 02-09-2012 |
20120127610 | MAGNETIC RECORDING METHOD USING MICROWAVE ASSISTED HEAD - A magnetic recording method for a recording layer of a magnetic recording medium uses a thin film magnetic head with a sub-coil or a microwave radiator. In the method, a microwave spread spectrum (SS) signal is applied to the sub-coil or the microwave radiator, the microwave SS signal including a ferromagnetic resonant (FMR) frequency of the recording layer as a carrier wave within a band so as to generate an in-plane high-frequency magnetic field so that a magnetization reversal magnetic field Hsw of the recording layer is lowered. The magnetic recording is performed while the magnetization reversal magnetic field Hsw of the recording layer is lowered. | 05-24-2012 |
20120230167 | MICROWAVE ASSISTED MAGNETIC HEAD AND MAGNETIC DISK DEVICE - A microwave assisted magnetic head of the present invention includes: at least two or more auxiliary coils that are arranged in a periphery of a writing main pole; and microwave current supply means that applies microwave currents to the at least two or more auxiliary coils. The at least two or more auxiliary coils respectively include linear body parts linearly arranged on an ABS side, two of the linear body parts of the at least two or more auxiliary coils are arranged in a substantially orthogonal positional relationship, and the microwave current supply means is configured such that the microwave current supply means changes phase differences of the microwave currents applied respectively to the at least two or more auxiliary coils. Therefore, the microwave current can be easily controlled, and thus, a circularly polarized magnetic field with high magnetization inversion efficiency can be generated as an assistance magnetic field. | 09-13-2012 |
20120243117 | METHOD FOR MAGNETIC RECORDING USING MICROWAVE ASSISTED MAGNETIC HEAD - An object is to provide a magnetic recording method that demonstrates an additional high assistance effect to magnetic recording by applying an alternate current magnetic field in the in-plane direction to a magnetic recording medium having a large coercive force, and a method of the present invention for magnetic recording using a magnetic recording head to a recording layer of a magnetic recording medium arranged to oppose the magnetic recording head, the magnetic recording head including a main pole, an auxiliary pole, a main coil for generating a perpendicular recording magnetic field to the main pole, and either a sub-coil for generating an in-plane alternate current magnetic field of a microwave band to the main pole or a microwave radiator that is arranged in vicinity of the main pole and that radiates microwaves, the method including: a step for modulating an amplitude of the in-plane alternate current magnetic field by modulating an amplitude of microwave alternating current that is applied to either the sub-coil or the microwave radiator using a modulation signal wave so that a ratio (fc/fm) of a carrier frequency (fc) to a modulation frequency (mf) is from 10 to 40; and a step for performing magnetic recording to the recording layer of the magnetic recording medium by applying the perpendicular recording magnetic field while applying the in-plane alternate current magnetic field with the modulated amplitude to the magnetic recording medium. | 09-27-2012 |
20120320474 | MICROWAVE ASSISTED MAGNETIC RECORDING HEAD AND MAGNETIC RECORDING METHOD THEREWITH - A microwave assisted magnetic head includes a main magnetic pole; a trailing shield, a main coil for causing the main magnetic pole to generate a perpendicular recording field, at least one secondary coil for generating an in-plane alternate-current (AC) magnetic field with a frequency in a microwave band from a magnetic recording gap between the main magnetic pole and the trailing shield, nonmagnetic films formed on magnetic recording gap facing surfaces that are defined by the main magnetic pole and the trailing shield, the main magnetic pole and the trailing shield being configured with first soil magnetic films, and second soft magnetic films formed further on the surfaces of the nonmagnetic films. The second soft magnetic films have larger anisotropy fields than the first soft magnetic films have. | 12-20-2012 |
20130301162 | APPARATUS FOR MEASURING MAGNETIC FIELD OF MICROWAVE-ASSISTED HEAD - A measuring circuit system in a magnetic field measuring apparatus of the invention has an amplifier and a band-pass filter connected in sequence on an output terminal side of the TMR element, the band-pass filter is a narrow-range band-pass filter such that a peak pass frequency of the filter that is a center is a basic frequency selected from a range of 10 to 40 GHz and a band width centered around the basic frequency is a narrow range of ±0.5 to ±4 GHz; and with the measuring circuit system, an S/N ratio (SNR) of 3 dB or greater is obtained, the SNR being defined by a ratio of an amplitude S of a high-frequency generated signal induced by the TMR element to a total noise N that is a sum of a head noise generated by the TMR element and a circuit noise generated by the amplifier. With such a configuration, an in-plane high-frequency magnetic field generated by a microwave-assisted magnetic head is reliably and precisely measured. | 11-14-2013 |