Abstract: A thermally-assisted magnetic recording head that allows even steeper magnetization reversal between adjacent magnetic domains of a magnetic recording medium and that satisfies the demands of high SN ratio and high recording density is provided. A thermally-assisted magnetic recording head includes a pole that generates a writing magnetic field, a waveguide through which light for exciting surface plasmon propagates, and a plasmon generator that generates near-field light. The waveguide is arranged on a back side of the pole, the plasmon generator has a plane part and a projection part that is projected from the plane part to the waveguide side and that opposes the pole and the waveguide with a predetermined gap, and a projection part opposing surface that opposes the projection part in the pole is configured so as to be distant from the projection part as approaching toward the back side.

Abstract: A magnetoresistive effect element is structured in the manner that the antiferromagnetic layer interposed between the upper and lower shields is eliminated and the antiferromagnetic layer is positioned in a so-called shield layer. Therefore, it is realized to solve a pin reversal problem and to allow narrower tracks and narrower read gaps.

Abstract: A method of manufacturing a thermally-assisted magnetic recording head includes: providing bar including, arranged in a first direction, a plurality of thermally-assisted magnetic recording head sections each including a waveguide, and a plurality of light source units each including a substrate with a light source mounted on a first surface of the substrate; bonding a second surface of the substrate to the bar with a bonding layer while allowing a light emitting position of the light source to be in opposition to the waveguide and allowing the first surface to be parallel to the first direction; and separating the bar for each of the thermally-assisted magnetic recording head sections. The substrate is bonded to the bar by radiating each laser beam from a dead angle direction where the first surface on which the light source units are provided is hidden from view.

Abstract: A thermally-assisted magnetic head that includes an air bearing surface facing a recording medium and that performs magnetic recording while heating the recording medium includes: a magnetic recording element including a pole of which one edge part is positioned on the air bearing surface and that generates magnetic flux traveling toward the magnetic recording medium; a waveguide configured with a core through which light propagates and a cladding, at least one part of which extends to the air bearing surface, surrounding the periphery of the core; a plasmon generator that faces a part of the core and that extends to the air bearing surface.

Abstract: A method of the invention for performing burn-in test includes assembling, on a fixture stand, a plurality of light source elements and a plurality of light detectors for monitoring a light output from a corresponding one of the plurality of light source elements; and electrifying the plurality of light source elements in a state where at least the plurality of light source elements and the plurality of light detectors are immersed in an insulation liquid. Thereby, it is realized to hold a stable temperature in a short period of time, to maintain a temperature that does not deviate from normal load conditions, and to perform a sorting test between defect parts and good part for light source unit chips without causing damage to the elements.

Abstract: The thermally assisted magnetic head comprises a medium-opposing surface; a magnetic recording device whose distance from a main magnetic pole to a medium is set longer than a distance from the medium-opposing surface to the medium; a first core for receiving light; and a second core positioned between a first light exit surface of the first core and the medium-opposing surface, having a second light exit surface on the medium side; while a distance between positions where an optical intensity distribution center within the first light exit surface and a center of the main magnetic pole are orthographically projected onto a reference plane including the second light exit surface is greater than a distance between an optical intensity distribution center within the second light exit surface and the position where the center of the leading end of the main magnetic pole is orthographically projected onto the reference plane.

Abstract: Provided is a method for manufacturing a thermally-assisted magnetic recording head with “composite slider structure”. In the method, the waveguide is irradiated with a first light from opposed-to-medium surface side, and the passing first light is detected on back surface side to obtain an image of the light-receiving end surface, and a light-receiving center position is determined from the image. Further, the light source is irradiated with a second light from opposite side to joining surface, and the passing second light is detected on the joining surface side to obtain an image of the light-emitting end surface, and a light-emitting center position is determined from the image. Then, the slider and the light source unit are moved based on the determined positions of the light-receiving and light-emitting centers, aligned and bonded. As a result, alignment can be performed with high accuracy in a short process time under simplified process.

Abstract: Provided is a thermally-assisted magnetic recording head comprising a near-field-light-generating (NFL-generating) optical system with an improved light use efficiency. The head comprises a magnetic pole, a waveguide propagating a light for exciting surface plasmon, and a NF-optical device configured to emit NF-light from its end surface located adjacent to the magnetic pole end surface. The waveguide cross-section, taken by a plane perpendicular to a waveguide edge along elongated direction, has substantially a trapezoidal shape in which a longer side of opposed parallel sides is an edge of the cross-section on the NF-optical device side. This configuration enables a coupled portion of the NF-optical device which is coupled with the light to be placed in the effective distribution range of the light seeping from the waveguide. Consequently, there can be realized a sufficiently strong coupling between the light seeping from the waveguide and the NF-optical device.

Abstract: A thermally-assisted magnetic recording method includes first and second steps. The first step applies heat to part of a hard disk medium and forms a moving high-temperature region in a magnetic recording layer of the hard disk medium. The high-temperature region is higher in temperature than a region therearound and has a temperature equal to or higher than the maximum coercivity vanishing temperature of a plurality of magnetic grains contained in the magnetic recording layer. At least one magnetic grain that is adjacent to the rear end of the high-temperature region in the direction of movement of the high-temperature region has a coercivity of a value other than 0. The second step applies a write magnetic field to the hard disk medium such that the write magnetic field applied to the at least one magnetic grain adjacent to the rear end of the high-temperature region is 3 kOe or smaller in magnitude.

Abstract: In a method of estimating the Curie temperature distribution of a plurality of magnetic grains contained in a magnetic recording layer, measurement values of first and second parameters are obtained for each of different temperatures of the magnetic recording layer which is used as the measurement subject. The first parameter has such a property that the absolute value of the first parameter for each magnetic grain takes on the minimum value when the temperature of each magnetic grain reaches a predetermined temperature, wherein the predetermined temperature varies according to the Curie temperature of each magnetic grain in such a manner as to increase as the Curie temperature increases, and to decrease as the Curie temperature decreases. The second parameter is related to the standard deviation of the coervicity distribution of the magnetic grains divided by the coervicity of the magnetic recording layer.

Abstract: A spot size converter according to the present invention is capable of shortening the waveguide length in the spot size converter and of promoting a size reduction of the optical waveguide itself because two cores having a taper portion are combined and those tapering angles are mutually aligned. Furthermore, spot size conversion efficiency is favorable even in a small size.

Abstract: Provided is a method for manufacturing a thermally-assisted magnetic recording head including a light source unit with a light source and a slider with an optical system. The method comprises steps of: adhering by suction the light source unit with a back holding jig; moving the back holding jig, then aligning a light-emission center of the light source with a light-receiving end surface of the optical system in directions within a slider back surface of the slider; bringing the light source unit into contact with the slider back surface, with a suction surface of the back holding jig tilted from the normal to the slider back surface; applying a load to a load application surface of the unit substrate by a loading means to bring a joining surface of the light source unit into conformity with the slider back surface; and bonding the light source unit and the slider. This method can improve the conformity, thereby achieving adequately strong junction and adequately high accuracy in position.

Abstract: Provided is a light source unit the weight of which can be reduced while ensuring power supply to the light source. The light source is configured to form a thermally-assisted magnetic recording head by being joined with a slider including an optical system that propagates light for thermal assist. The light source unit comprises: a unit substrate including a joining surface that faces an power-supply electrode of the slider; a first electrode provided on the joining surface; a second electrode provided on a source-installation surface and electrically connected to the first electrode; and a light source that includes two electrode layers and a light-emission center located in a light-emitting surface. The first and second electrodes eliminate the provision of a terminal electrode for light source on the source-integration surface. As a result, the weight of the light source unit can be reduced.

Abstract: Provided is a surface plasmon resonating optical system emitting near-field light (NF-light) with a higher light density. The system comprises: a waveguide through which a light for exciting surface plasmon propagates; a plasmon generator that couples with the light in a surface plasmon mode and emits NF-light from its NF-light generating end surface; and a resonator mirror that reflects the excited surface plasmon, provided on the side of the plasmon generator opposite to the NF-light generating end surface. In the system, the excited surface plasmon can be amplified by using a resonator structure while reducing the length of the plasmon generator to reduce absorption of surface plasmon and prevent overheating of the plasmon generator.

Abstract: A method for manufacturing a thermally-assisted magnetic recording head is provided, in which a light source unit including a light source and a slider including an optical system are bonded. A unit substrate is made of a material transmitting light having a predetermined wavelength, and an adhesion material layer is formed on the light source unit and/or the slider. The manufacturing method includes: aligning the light source unit and the slider in such a way that a light from the light source can enter the optical system and the adhesion material layer is sandwiched therebetween; irradiating the adhesion material layer with a light including the predetermined wavelength through the unit substrate; and bonding them. The adhesion material layer melted by the light including the predetermined wavelength and transmitted through the unit substrate can ensure high alignment accuracy as well as higher bonding strength and less change with time.

Abstract: A method for manufacturing a thermally-assisted magnetic recording head is provided, in which a light source unit including a light source and a slider including an optical system are bonded. A unit substrate is made of a material transmitting light having a predetermined wavelength, and a unit adhesion material layer that contains Sn, Sn alloy, Pb alloy or Bi alloy is formed on the light source unit and/or the slider. The manufacturing method includes: aligning the light source unit and the slider in such a way that a light from the light source can enter the optical system and the unit adhesion material layer is sandwiched therebetween; and causing a light including the predetermined wavelength to enter the unit substrate to melt the unit adhesion material layer. The unit adhesion material layer melted by the light including the predetermined wavelength can ensure high alignment accuracy as well as higher bonding strength and less change with time.

Abstract: Provided is a head gimbal assembly (HGA) in which the electrodes for a thermally-assisted magnetic recording head comprising a light source, a photodetector and a magnetic head element, can be reliably electrically connected to wiring members by solder ball bonding (SBB). The HGA comprises a suspension comprising: a base; a first wiring member for the light source and the photodetector, provided on a side of one surface of the base; and a second wiring member for the magnetic head element, provided on the same surface side. The first and second wiring members protrude from the base toward the head to be fixed. As a result, the end portions (connection pads) of the first and second wiring members can be located close to electrodes for light-source and photodetector and electrodes for magnetic head element, respectively. This arrangement enables the end portions of the first and second wiring members to be reliably electrically connected to the electrodes by SBB.

Abstract: Provided is a method and apparatus to manufacture a thermally-assisted magnetic recording head in which a light source unit including a light source and a slider including an optical system are joined. The method comprises steps of: adhering by suction the light source unit with a back holding jig; bringing the light into contact with a slider back surface; applying a load to a load application surface of the light source unit by a loading means to bring a joining surface of the light source unit into conformity with the slider back surface; positioning the light source unit apart from the slider, and then aligning the light source with the optical system; bringing again the light source unit into contact with the slider; and applying a load again to the load application surface.

Abstract: Provided is a heat-assisted magnetic recording head constituted of a light source unit and a slider, which can be easily joined to each other with sufficiently high accuracy of joining position. The slider comprises a head part including a waveguide having an incident center on its end. The surface including an emission center of the light source is protruded from a joining surface of the unit substrate. And a step is provided on an end surface of the head part. The protruded portion of a lower surface of the light source has a surface contact with a wall surface of the step. Further, the distance between the wall surface of the step and the incident center of the waveguide is set to be equal to the distance between the emission center of the light source and the protruded portion of the lower surface of the light source.

Abstract: A thermally assisted magnetic head includes a main magnetic pole for writing and a near-field light generator provided near the main magnetic pole, the near-field light generator having a non-magnetic base metal layer, a non-magnetic upper metal layer, an intermediate insulating layer interposed between the base metal layer and the upper metal layer, and the base metal layer having a V-shaped groove and also the upper metal layer having a projection facing the deepest part in the groove of the base metal layer, in a vertical cross-section parallel to a medium facing surface.