Abstract: To suppress a spread of not only a recording magnetic field generated from a main pole but also a high-frequency magnetic field generated from a spin torque oscillator in a microwave assisted magnetic recording head. The main pole and the spin torque oscillator are surrounded by a trailing shield layer and are also surrounded by a side/leading shield layer with an insulator sidegap layer interposed therebetween, and a high-frequency magnetic field shield layer, which absorbs a high-frequency magnetic field generated from the spin torque oscillator, is arranged in at least part of the shield layers.

Abstract: Provided are a structure of a high frequency magnetic field assisted magnetic recording head in which the positional relationship of a main magnetic pole and a spin torque oscillator in a cross-track direction is accurately determined, and in which variations are not caused in high frequency magnetic field assist characteristics, and a method of manufacturing the structure. The high frequency magnetic field assisted magnetic recording head includes a main magnetic pole, a spin torque oscillator disposed on the main magnetic pole, and an insulating side gap covering a side surface of the main magnetic pole and a side surface of the spin torque oscillator. The main magnetic pole and the spin torque oscillator are formed between both side surfaces of the side gap. Thus, a self-alignment structure of the high frequency magnetic field assisted magnetic recording head is obtained.

Abstract: Provided is a magnetic recording medium achieving both of reduction in switching field distribution and reduction in switching field intensity by high-frequency magnetic field, thus enabling high-density recording. Magnetic grains of the magnetic recording medium are made up of a recording layer and a resonance layer. The resonance layer is disposed closer to a protective layer 5 than the recording layer, and a magnetic material of the recording layer has anisotropy field 1.2 times or more anisotropy field of a magnetic material of the resonance layer. The magnetic material of the recording layer has saturation magnetization substantially equal to saturation magnetization of the magnetic material of the resonance layer. At the entire resonance layer and a part of the recording layer, the magnetic grains are separated from surrounding magnetic grains by a nonmagnetic material, and at a part of the recording layer, the magnetic grains are coupled with surrounding magnetic grains.

Abstract: Provided are a structure of a high frequency magnetic field assisted magnetic recording head in which the positional relationship of a main magnetic pole and a spin torque oscillator in a cross-track direction is accurately determined, and in which variations are not caused in high frequency magnetic field assist characteristics, and a method of manufacturing the structure. The high frequency magnetic field assisted magnetic recording head includes a main magnetic pole, a spin torque oscillator disposed on the main magnetic pole, and an insulating side gap covering a side surface of the main magnetic pole and a side surface of the spin torque oscillator. The main magnetic pole and the spin torque oscillator are formed between both side surfaces of the side gap. Thus, a self-alignment structure of the high frequency magnetic field assisted magnetic recording head is obtained.

Abstract: To realize a highly reliable magnetic head for a high-frequency magnetic field assisted recording system by preventing current crowding in an oscillator and increasing the current resistance of the oscillator. Between a main pole that generates a recording magnetic field and a trailing shield, an oscillator that includes a non-magnetic metal layer, a spin injection pinned layer, an intermediate layer, and a high-frequency magnetic field generation layer and that generates a high-frequency magnetic field is disposed. The non-magnetic metal layer adjacent to the main pole is tapered with the width gradually increasing from the trailing side toward the leading side.

Abstract: A magnetic recording head used for microwave-assisted magnetic recording includes: a main pole; a spin torque oscillator provided on the main pole, including a high-speed rotating magnetization layer in which the magnetization is rapidly rotated by a spin torque; a trailing shield provided on the spin torque oscillator; and a sub pole magnetically coupled to the trailing shield provided in a medium-facing surface, extending in a vertical direction to the medium-facing surface. Then, a non-magnetic electrode is provided on the outside of a trailing gap in which the spin torque oscillator is provided with respect to a magnetic material of the main pole, the trailing shield, or the sub pole, to prevent the line resistance variation due to the AMR effect or the eddy current. Thus, the variation of the current flowing to the spin torque oscillator can be controlled to achieve stable oscillation.

Abstract: In a magnetic head of a high-frequency magnetic field assisted recording system, a width of a high-frequency magnetic field from an oscillator is decreased to enhance an oscillation frequency, in order to realize a high-density recording. An oscillator provided near a main pole, which generates a recording magnetic field, for generating a high-frequency magnetic field is patterned by a conventional photolithography, and then, an oxidation, nitridation, or oxynitridation is performed on the side face in a track width direction. With this process, an oxide layer, a nitride layer, or an oxynitride layer, which is made of a material of the oscillator, is formed on the side face of the oscillator in the track width direction, and the shape of the oscillator is formed to be semi-circular.

Abstract: Embodiments in accordance with the present invention provide a magnetic head of the CPP structure for perpendicular magnetic recording, that is excellent in read performance, and stable in write/read performances by enhancing the external field durability, and further, suppresses deterioration in read sensor property, due to thermal factors. At least either shield layer of a lower magnetic shield layer, and an upper magnetic shield layer, closer to a perpendicular magnetic write head, is made up so as to have a multi-layered structure comprising low thermal expansion nonmagnetic layers, and magnetic layers. Material having a coefficient of thermal expansion smaller than that of a magnetoresistive film is selected as a material for the low thermal expansion nonmagnetic layers of the shield layer.

Abstract: The strength of a magnetic field applied from a main pole to an oscillator and the strength of a magnetic field applied from the main pole to a recording medium are improved in a magnetic recording head for microwave assisted recording. In the magnetic recording head according to the present invention, an interval between the main pole and a trailing shield at a place in a position above an air bearing surface is larger than an interval between the main pole and the trailing shield on the air bearing surface.

Abstract: To realize a highly reliable magnetic head for a high-frequency magnetic field assisted recording system by preventing current crowding in an oscillator and increasing the current resistance of the oscillator. Between a main pole that generates a recording magnetic field and a trailing shield, an oscillator that includes a non-magnetic metal layer, a spin injection pinned layer, an intermediate layer, and a high-frequency magnetic field generation layer and that generates a high-frequency magnetic field is disposed. The non-magnetic metal layer adjacent to the main pole is tapered with the width gradually increasing from the trailing side toward the leading side.

Abstract: In a Spin Torque Oscillator (STO) comprising an underlayer, a first magnetic layer disposed on the underlayer, a non-magnetic intermediate layer disposed on the first magnetic layer, and a second magnetic layer disposed on the non-magnetic intermediate layer, the non-magnetic intermediate layer is a non-magnetic alloy containing 50 at % or more of at least one kind of element selected from a first group consisting of Cu, Ag, and Au, and further at least 0.1 at % or more in total of at least one kind of element selected from a second group consisting of Cu, Ag, Au, Cr, Ti, Zr, Hf, V, Nb, Ta, Ru, Os, Pd, Pt, Rh, and Ir that does not overlap with the element from the first group.

Abstract: To provide a spin torque oscillator which is adapted to high data transfer rates and which can perform assisted magnetic recording of sufficient magnitude. A spin torque oscillator is provided with a stacked spin injection layer and a high frequency magnetic field generation layer. The stacked spin injection layer has a stacked structure in which a first magnetic layer, a coupling layer, and a second magnetic layer are stacked in the order mentioned from a far side as viewed from the high frequency magnetic field generation layer. Magnetization of the first magnetic layer and magnetization of the second magnetic layer are coupled antiparallel to each other. A polarity of the magnetization of the second magnetic layer is reversed temporally earlier than a magnetic field polarity reversal of a leakage magnetic field from the main magnetic pole.

Abstract: To suppress a spread of not only a recording magnetic field generated from a main pole but also a high-frequency magnetic field generated from a spin torque oscillator in a microwave assisted magnetic recording head. The main pole and the spin torque oscillator are surrounded by a trailing shield layer and are also surrounded by a side/leading shield layer with an insulator sidegap layer interposed therebetween, and a high-frequency magnetic field shield layer, which absorbs a high-frequency magnetic field generated from the spin torque oscillator, is arranged in at least part of the shield layers.

Abstract: Provided is a magnetic recording medium achieving both of reduction in switching field distribution and reduction in switching field intensity by high-frequency magnetic field, thus enabling high-density recording. Magnetic grains of the magnetic recording medium are made up of a recording layer and a resonance layer. The resonance layer is disposed closer to a protective layer 5 than the recording layer, and a magnetic material of the recording layer has anisotropy field 1.2 times or more anisotropy field of a magnetic material of the resonance layer. The magnetic material of the recording layer has saturation magnetization substantially equal to saturation magnetization of the magnetic material of the resonance layer. At the entire resonance layer and a part of the recording layer, the magnetic grains are separated from surrounding magnetic grains by a nonmagnetic material, and at a part of the recording layer, the magnetic grains are coupled with surrounding magnetic grains.

Abstract: According to one embodiment, a magnetoresistive head has a magnetoresistive sensor film between a lower shield layer and an upper shield layer. The magnetoresistive sensor film is formed by stacking at least a pinning layer, a first ferromagnetic layer, an intermediate layer, and a second ferromagnetic layer, in which a sense current flows so as to pass through an interface between the intermediate layer and the second ferromagnetic layer, and a resistance change of the magnetoresistive sensor film in accordance with the change of an external magnetic field is detected. Also, a lateral side metal layer having an electric resistivity lower than the electric resistivity of the pinning layer is disposed at least on a side wall of the pinning layer among side walls of layers constituting the magnetoresistive sensor film, the lateral side metal layer being in contact with the lower shield layer. Other embodiments are described as well.

Abstract: A microwave assisted magnetic recording head includes a recording magnetic pole unit that produces a recording field for writing to a perpendicular magnetic recording medium, and a high-frequency magnetic field oscillator that produces a high-frequency magnetic field. The recording magnetic pole unit includes a magnetic core with a write gap portion at which a main recording field component is concentrated, and the high-frequency magnetic field oscillator is disposed in the write gap.

Abstract: According to one embodiment, a high-frequency magnetic field-assisted magnetic recording head includes a main pole adapted for producing a writing magnetic field, a STO positioned above the main pole, a low-resistance layer positioned above the STO, and a current confinement layer positioned between the low-resistance layer and the main pole, wherein the main pole and the low-resistance layer are adapted for acting as poles for writing data to a magnetic medium in response to a flow of current to the STO positioned therebetween to generate a high-frequency magnetic field which overlaps with the writing magnetic field, and wherein the current confinement layer is adapted for controlling a current density and/or a current density distribution of the current flowing to the STO. Other magnetic recording heads and methods of production thereof are also described according to more embodiments.

Abstract: Embodiments of the present invention help to reduce etching damage at end parts of a magnetoresistive sensor in ion beam etching. According to one embodiment, ion beam etching (IBE) is used in a magnetoresistive sensor track width forming step. This IBE irradiates Ar ion beam to a substrate in a state that the substrate is inclined and further rotates the substrate about its normal as a rotational axis. In a conventional track width forming step, the IBE irradiates the Ar ion beam to the substrate all the time while the IBE is rotating the substrate. By contrast, the IBE according to embodiments of the present invention irradiates the Ar ion beam to the substrate only in a predetermined specific angular range.

Abstract: A magnetic recording head used for microwave-assisted magnetic recording includes: a main pole; a spin torque oscillator provided on the main pole, including a high-speed rotating magnetization layer in which the magnetization is rapidly rotated by a spin torque; a trailing shield provided on the spin torque oscillator; and a sub pole magnetically coupled to the trailing shield provided in a medium-facing surface, extending in a vertical direction to the medium-facing surface. Then, a non-magnetic electrode is provided on the outside of a trailing gap in which the spin torque oscillator is provided with respect to a magnetic material of the main pole, the trailing shield, or the sub pole, to prevent the line resistance variation due to the AMR effect or the eddy current. Thus, the variation of the current flowing to the spin torque oscillator can be controlled to achieve stable oscillation.

Abstract: The strength of a magnetic field applied from a main pole to an oscillator and the strength of a magnetic field applied from the main pole to a recording medium are improved in a magnetic recording head for microwave assisted recording. In the magnetic recording head according to the present invention, an interval between the main pole and a trailing shield at a place in a position above an air bearing surface is larger than an interval between the main pole and the trailing shield on the air bearing surface.