Heat Transfer Structure Patents (Class 360/125.32)
  • Patent number: 10811034
    Abstract: A microwave-assisted magnetic recording writer is disclosed wherein a heat sink is formed in a write gap (WG) and adjacent to a spin torque oscillator (STO) formed between a main pole (MP) trailing side and a trailing shield (hot seed layer). The WG comprises an electrically insulating layer with thickness of 5-80 Angstroms on the MP trailing side and STO sides. The heat sink layer may be separate coplanar layers on each STO side, or a single layer wrapping around the STO. A Ru or Cu heat sink has sufficient thermal conductivity to reduce STO temperature rise by 11% and 20%, respectively. Accordingly, the STO has longer lifetime at the same bias current density, or higher buffer head voltage is possible while maintaining STO device reliability. Each heat sink has a front side at an air bearing surface, and a stripe height (SH)?to the STO SH.
    Type: Grant
    Filed: April 1, 2019
    Date of Patent: October 20, 2020
    Assignee: Headway Technologies, Inc.
    Inventors: Yan Wu, Kowang Liu
  • Patent number: 10783943
    Abstract: A STT-MRAM comprises apparatus, a method of operating and a method of manufacturing a self-referenced magnetoresistive memory and a plurality of magnetoresistive memory element including a self-referenced read scheme through a write/read circuitry coupled to the bit line positioned adjacent to selected ones of the plurality of magnetoresistive memory elements to supply bi-directional spin-transfer recording and reading currents across the MTJ stack. Thus magnetization of a recording layer can be readily switched or reversed to the direction in accordance with a direction of a current across the MTJ stack by applying a spin transfer current, and the magnetization of a reference layer can be readily rotated to two reading directions subsequently in accordance with directions of currents across the MTJ stack by applying low spin transfer currents.
    Type: Grant
    Filed: February 17, 2014
    Date of Patent: September 22, 2020
    Inventor: Yimin Guo
  • Patent number: 10360932
    Abstract: A method for manufacturing a magnetic write head having a heat sink structure, wherein the magnetic write head is free of voids at the media facing surface. After forming the write pole, a chemical mechanical polishing process is performed prior to defining the heat sink structure. Planarizing the write pole structure by chemical mechanical polishing prior to forming the heat sink structure advantageously reduces the topography over which the heat sink structure. This mitigates shadowing effects from the write pole structure and prevents the formation of voids at the media facing surface.
    Type: Grant
    Filed: December 5, 2016
    Date of Patent: July 23, 2019
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Aron Pentek, Takuya Matsumoto, Venkata R K Gorantla
  • Patent number: 10109302
    Abstract: A magnetic recording head is provided with a main magnetic pole that generates a recording magnetic field to be applied to a magnetic recording medium from an end surface which makes a portion of an air bearing surface, a trailing shield that is placed by interposing a write gap at a trailing side of the main magnetic pole, a spin torque oscillator that is placed within the write gap to be between the main magnetic pole and the trailing shield, and two side shields that are placed at both sides of the main magnetic pole in the cross track direction, and when viewed from the air bearing surface side, at least a portion of the trailing-side end surfaces of the side shields are offset toward a leading-side of the main magnetic pole from the leading-side end surface of the spin torque oscillator.
    Type: Grant
    Filed: July 18, 2017
    Date of Patent: October 23, 2018
    Assignee: TDK Corporation
    Inventors: Tetsuhito Shinohara, Tetsuya Roppongi, Naomichi Degawa
  • Patent number: 10032470
    Abstract: A magnetic recording head comprises: a main magnetic pole for generating a recording magnetic field applied to a magnetic recording medium from an end surface that is one part of an air bearing surface facing the magnetic recording medium; a trailing shield that is placed by interposing a write gap at a trailing side of the main magnetic pole; and a spin torque oscillator provided in the write gap; wherein, when viewed from the air bearing surface side, the length in the down-track direction between the trailing shield and the cross-track direction end portion of a first end face positioned at the main magnetic pole side of the spin torque oscillator is longer than the length in the down-track direction between the trailing shield and the main magnetic pole at a center position in the cross-track direction of the spin torque oscillator.
    Type: Grant
    Filed: July 14, 2017
    Date of Patent: July 24, 2018
    Assignee: TDK Corporation
    Inventors: Naomichi Degawa, Tetsuhito Shinohara, Shinji Hara, Tetsuya Roppongi
  • Patent number: 9953675
    Abstract: A system, according to one embodiment, includes: a main pole; and a trailing shield. A first distance D1 is defined in a track direction between the trailing shield and a pole tip region of the main pole; and a second distance D2 is defined in the track direction between the trailing shield and a second region of the main pole located behind the pole tip region, where D2 is greater than D1. Other systems, and methods are described in additional embodiments.
    Type: Grant
    Filed: October 9, 2017
    Date of Patent: April 24, 2018
    Assignee: Western Digital Technologies, Inc.
    Inventors: Kuok San Ho, Suping Song, Petrus Antonius Van Der Heijden
  • Patent number: 9431036
    Abstract: Thermal energy is generated within an optical NFT when in operation within a HAMR head. A heat-sink assembly within the HAMR head extracts thermal energy from the optical NFT and transmits the thermal energy via convection to air surrounding the HAMR head, radiation to surfaces adjacent to the HAMR head, and/or conduction to other parts of the HAMR head. The thermal energy generated within the optical NFT is conducted to the heat-sink. An air-bearing surface of the heat-sink convectively transfers at least some of the thermal energy to air passing between the air-bearing surface and a surface of an adjacent magnetic medium. Further, some of the thermal energy may also radiatively transfer from the air-bearing surface to the magnetic medium.
    Type: Grant
    Filed: December 22, 2010
    Date of Patent: August 30, 2016
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: William Paul Vavra, Xiaoyue Huang, Michael Christopher Kautzky, Kaizhong Gao
  • Patent number: 9019661
    Abstract: An apparatus comprises a write transducer comprising a write pole having a tip portion proximate a media-facing surface and a return pole spaced apart from the write pole in a downtrack direction. The apparatus further includes first and second heat sink portions. The first heat sink portion surrounds a first side of the tip portion that faces the return pole and extends outwards from the tip portion in a cross-track direction. The second heat sink portion comprises a first surface proximate the first heat sink portion and a second surface proximate the return pole and extends outwards in the cross-track direction further than the first heat sink portion.
    Type: Grant
    Filed: August 7, 2013
    Date of Patent: April 28, 2015
    Assignee: Seagate Technology LLC
    Inventors: Chris Rea, Zoran Jandric, Hua Zhou
  • Publication number: 20150109699
    Abstract: In accordance with one embodiment, a magnetic head includes a main pole configured to emit a recording magnetic field for affecting a magnetic medium, spin torque oscillator (STO) device in electrical communication with and positioned above the main pole in a track direction, the STO device being configured to generate a high-frequency magnetic field which is superimposed with the recording magnetic field in order to record data to the magnetic medium when current flows to the STO device, and a heat sink positioned near the STO device, the heat sink being configured to reduce a temperature of the STO device when current flows to the STO device. In another embodiment, a method includes forming a heat sink behind a STO device in an element height direction perpendicular to a media facing surface, and/or on both sides of the STO device in a cross-track direction at the media facing surface.
    Type: Application
    Filed: October 22, 2013
    Publication date: April 23, 2015
    Applicant: HGST Netherlands B.V.
    Inventors: Carl Boone, Jianhua Li, Isao Nunokawa, Erhard Schreck, Mikito Sugiyama, Ikuya Tagawa, Yuta Udo
  • Patent number: 8995088
    Abstract: In accordance with one embodiment, a magnetic head includes a main pole configured to emit a recording magnetic field for affecting a magnetic medium, a spin torque oscillator (STO) device in electrical communication with and positioned above the main pole in a track direction, the STO device being configured to generate a high-frequency magnetic field which is superimposed with the recording magnetic field in order to record data to the magnetic medium when current flows to the STO device, and a heat sink positioned near the STO device, the heat sink being configured to reduce a temperature of the STO device when current flows to the STO device. In another embodiment, a method includes forming a heat sink behind a STO device in an element height direction perpendicular to a media facing surface, and/or on both sides of the STO device in a cross-track direction at the media facing surface.
    Type: Grant
    Filed: October 22, 2013
    Date of Patent: March 31, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: Carl Boone, Jianhua Li, Isao Nunokawa, Erhard Schreck, Mikito Sugiyama, Ikuya Tagawa, Yuta Udo
  • Patent number: 8945731
    Abstract: A device that includes a near field transducer (NFT); at least one cladding layer adjacent the NFT; and a discontinuous metal layer positioned between the NFT and the at least one cladding layer.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: February 3, 2015
    Assignee: Seagate Technology LLC
    Inventors: Tong Zhao, Michael Christopher Kautzky, Michael Allen Seigler, Yongjun Zhao, Jay Jayashankar, Xiaoyue Huang
  • Patent number: 8854930
    Abstract: Techniques for improving the recording quality during heat assisted magnetic recording (HAMR) by monitoring the power of a source used to heat a storage medium are described. In one example, a source emits electromagnetic radiation. A waveguide transmits the electromagnetic radiation onto a surface of a magnetic media. A photoresistive material is proximately located to the waveguide. The resistance of the photoresistive material varies based on the intensity of electromagnetic radiation propagating through the waveguide. The power of the source is determined by measuring the resistance of the photoresitive material. The power of the source is adjusted based on the determined power.
    Type: Grant
    Filed: August 2, 2013
    Date of Patent: October 7, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Thomas William Clinton, Takuya Matsumoto, Shen Ren, Erhard Schreck, Barry Cushing Stipe
  • Patent number: 8817425
    Abstract: A read head structure is disclosed with a dual piece heat sink layer having a front piece formed over a front portion of a dynamic flying height (DFH) element and a back piece above a back portion of the DFH element. A first (S1) shield is formed on the front piece and between the front piece and air bearing surface (ABS). Front and back pieces are separated by an insulator gap. The front piece is used to help control read gap protrusion. As a result, a bottom portion of the S1 shield protrudes to a greater extent than a top portion adjacent to the sensor thereby protecting the sensor from unwanted contact with the magnetic media. The dual piece heat sink layer also enables an improved Figure of Merit in terms of temperature rise in the reader per unit of actuation (nm) delivered by the DFH element.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: August 26, 2014
    Assignee: Headway Technologies, Inc.
    Inventors: Yan Wu, Kowang Liu, Glen Garfunkel, Min Li
  • Patent number: 8817407
    Abstract: An apparatus that includes a write pole, the write pole including a magnetic material; a near field transducer-heat sink (NFT-HS), the NFT-HS including a noble metal; and a power source configured to electrically bias the write pole with respect to a second structure.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: August 26, 2014
    Assignee: Seagate Technology LLC
    Inventors: James G. Wessel, Steven C. Riemer, Zoran Jandric
  • Patent number: 8786984
    Abstract: In one embodiment, a magnetic head includes a main pole configured to produce a magnetic writing field applied to a magnetic medium at an overall angle with respect to a magnetic anisotropy axis which is oriented in a direction perpendicular to a plane of a surface of the magnetic medium, and at least one current carrying element positioned near a media facing surface of the main pole configured to produce an assisting magnetic field applied in a cross-track direction parallel to the plane of the surface of the magnetic medium. In another embodiment, a method includes applying a writing magnetic field to write data to a magnetic medium and applying an assisting magnetic field to the magnetic medium for assisting the writing magnetic field, the assisting magnetic field being applied in a cross-track direction of the magnetic medium and parallel to a plane of a surface of the magnetic medium.
    Type: Grant
    Filed: November 15, 2011
    Date of Patent: July 22, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Sarbanoo Das, Masafumi Mochizuki
  • Publication number: 20140160598
    Abstract: A magnetic head includes a main magnetic pole, a trailing shield that forms a magnetic circuit with the main magnetic pole, a spin torque oscillator that is provided between the main magnetic pole and the trailing shield, a first cooling layer that partially has a Heusler structure, and a second cooling layer that is provided on the first cooling layer and mainly comprised of silver. The first cooling layer and the second cooling layer are provided either between the main magnetic pole and spin torque oscillator or between the trailing shield and the spin torque oscillator, with either of the two cooling layers being disposed closer to the spin torque oscillator. A third cooling layer may be formed to be in contact with the first cooling layer.
    Type: Application
    Filed: June 11, 2013
    Publication date: June 12, 2014
    Inventors: Masahiro TAKASHITA, Shuichi MURAKAMI, Naoki HASE, Katsuhiko KOUI
  • Patent number: 8605387
    Abstract: A thermally-assisted magnetic recording head includes a magnetic pole and a heating element. The magnetic pole has a front end face located in a medium facing surface. The magnetic pole forms on a track a distribution of write magnetic field strength that peaks at a first position on the track. The heating element forms on the track a distribution of temperature that peaks at a second position on the track. The first position is located on the trailing side relative to the second position. The front end face of the magnetic pole has a main portion and first and second extended portions. The first and second extended portions are extended in the track width direction from the main portion at positions on the leading side relative to the center of the main portion in the direction of travel of a magnetic recording medium.
    Type: Grant
    Filed: March 5, 2012
    Date of Patent: December 10, 2013
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Kosuke Tanaka, Tetsuya Roppongi
  • Patent number: 8587900
    Abstract: An apparatus for cooling a nanowire in a wire assisted magnetic recording head using a radiator in close proximity to a shield of the write pole. The radiator may further contain current restraints (e.g., slits, cuts, or resistive materials) that maximize current density in the nanowire at a location that corresponds to the current restraints. These current restraints may be further arranged to align with a write pole such that the current is forced to flow primarily through the nanowire when the nanowire is closest to the write pole. The nanowire may then be used either as main or auxiliary writing element for recording signals to a high coercivity media. Moreover, the nanowire and radiator may be combined into a single nanofoil which has a least two portions that perform a similar function as both the nanowire and radiator.
    Type: Grant
    Filed: May 24, 2011
    Date of Patent: November 19, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Luiz M. Franca-Neto, Bruce A. Gurney, Lidu Huang, Vijay P. S. Rawat, Petrus A. Van Der Heijden
  • Patent number: 8451555
    Abstract: An apparatus includes a waveguide having a core layer and an end adjacent to an air bearing surface, first and second poles magnetically coupled to each other and positioned on opposite sides of the waveguide, wherein the first pole includes a first portion spaced from the waveguide and a second portion extending from the first portion toward the air bearing surface, with the second portion being structured such that an end of the second portion is closer to the core layer of the waveguide than the first portion, and a heat sink positioned adjacent to the second portion of the first pole.
    Type: Grant
    Filed: February 24, 2009
    Date of Patent: May 28, 2013
    Assignee: Seagate Technology LLC
    Inventors: Michael Allen Seigler, Mark William Covington, Michael Leigh Mallary, Hua Zhou, Amit Vasant Itagi
  • Patent number: 8339739
    Abstract: A write head structure for use with thermally assisted recording is disclosed. Improved heat sinking is provided for removing thermal energy created by a ridge aperture near field light transducer. Metal films conduct heat away from the region near the ridge aperture to the high pressure air film at the ABS between the head and media. This heat is further dissipated by the media. The metal films have varying thickness to improve lateral conductivity and may be composed of Au combined with a harder metal such as Ru to improve wear characteristics at the ABS.
    Type: Grant
    Filed: August 31, 2010
    Date of Patent: December 25, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hamid Balamane, Jordan Asher Katine, Neil Leslie Robertson, Barry Cushing Stipe
  • Patent number: 8295010
    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.
    Type: Grant
    Filed: March 24, 2008
    Date of Patent: October 23, 2012
    Assignee: TDK Corporation
    Inventors: Koji Shimazawa, Kosuke Tanaka, Hiraku Hirabayashi
  • Patent number: 8159782
    Abstract: A thin film magnetic head is provided, in which the amount of protrusion in the periphery of an element portion can be reduced or a local temperature increase of electrode leads of a heating element can be prevented. The thin film magnetic head includes a playback element disposed between lower and upper shield layers, a recording element laminated on the upper shield layer, a heating element which is disposed below a coil layer and which generates heat to allow the playback element to protrude toward the recording medium side through thermal expansion, and a pair of electrode leads including overlapping regions, which are in contact with rear ends of the heating element and which overlap with the upper shield layer, and heat dissipation regions. Furthermore, connection wiring portions of the pair of electrode leads are disposed in a region sandwiched between the upper shield layer and a magnetic layer.
    Type: Grant
    Filed: February 4, 2011
    Date of Patent: April 17, 2012
    Assignee: TDK Corporation
    Inventors: Kiyoshi Kobayashi, Sumihito Morita, Tomoo Otsuka
  • Patent number: 8031432
    Abstract: A magnetic write head having a write coil configured to dissipate heat away from the write head to minimize thermal protrusion. The write coil is formed as a helical coil having upper and lower leads that are connected by electrically conductive studs formed therebetween. The first and leads extend beyond the studs to form heat conducting fins that conduct heat away from the write head where it can be dissipated into surrounding structure.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: October 4, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Wen-Chien David Hsiao, Edward Hin Pong Lee, Jennifer Ai-Ming Leung
  • Patent number: 8031435
    Abstract: An apparatus comprises a magnetic write pole, and a cooling device positioned adjacent to the magnetic write pole. The magnetic write pole can comprise a rare earth metal, or an alloy including a rare earth metal. A method of using a cooling device to increase a magnetic moment of a portion of a magnetic write pole in a magnetic recording head is also provided.
    Type: Grant
    Filed: December 18, 2006
    Date of Patent: October 4, 2011
    Assignee: Seagate Technology LLC
    Inventor: Thomas Francis Ambrose
  • Patent number: 7952827
    Abstract: A heat-assisted magnetic head that can efficiently and locally heat a magnetic recording medium. The head includes a heating coil element, and a write head element for writing data signals by generating a signal magnetic field, and a read head element for reading data signals by sensing the signal magnetic field. The heating coil element comprises a main heating magnetic pole layer, an auxiliary heating magnetic pole layer, and a heating coil layer for generating a magnetic flux in the main heating magnetic pole layer and the auxiliary heating magnetic pole layer and passing through at least between the main heating magnetic pole layer and the auxiliary heating magnetic pole layer. The read head element, heating coil element, and the write head element are stacked in this order from an element-formed surface of a substrate.
    Type: Grant
    Filed: July 20, 2007
    Date of Patent: May 31, 2011
    Assignee: TDK Corporation
    Inventors: Naoki Ohta, Kosuke Tanaka
  • Patent number: 7903373
    Abstract: A thin film magnetic head is provided, in which the amount of protrusion in the periphery of an element portion can be reduced or a local temperature increase of electrode leads of a heating element can be prevented. The thin film magnetic head includes a playback element disposed between lower and upper shield layers, a recording element laminated on the upper shield layer, a heating element which is disposed below a coil layer and which generates heat to allow the playback element to protrude toward the recording medium side through thermal expansion, and a pair of electrode leads including overlapping regions, which are in contact with rear ends of the heating element and which overlap with the upper shield layer, and heat dissipation regions. Furthermore, connection wiring portions of the pair of electrode leads are disposed in a region sandwiched between the upper shield layer and a magnetic layer.
    Type: Grant
    Filed: May 18, 2007
    Date of Patent: March 8, 2011
    Assignee: TDK Corporation
    Inventors: Kiyoshi Kobayashi, Sumihito Morita, Tomoo Otsuka
  • Patent number: 7894160
    Abstract: A thin-film magnetic head which can locally project a reproduction element toward a recording medium and a method of manufacturing the thin-film magnetic head are provided. The thin-film magnetic head includes a reproduction element, a recording element which is stacked on the reproduction element and has a pair of magnetic core layers and a coil layer configured to apply a recording magnetic field to the magnetic core layers, and a heat-emitting member emitting heat by electrification, which causes the reproduction element to project toward the recording medium by thermal expansion. The heat-emitting member is disposed below the coil layer.
    Type: Grant
    Filed: March 9, 2007
    Date of Patent: February 22, 2011
    Assignee: TDK Corporation
    Inventors: Kiyoshi Kobayashi, Kunio Koizumi, Kenji Ichinohe
  • Patent number: 7848056
    Abstract: A thin film magnetic head includes a main magnetic pole layer conducting a magnetic flux to the recording medium so that the recording medium an be magnetized in a direction orthogonal to a surface thereof; a return yoke layer disposed on a trailing side of the main magnetic pole layer; an intermediate protective layer partially disposed on a magnetic shield layer; and a thermal expansion suppressing layer having an edge located on the intermediate protective layer and being in contact with the return yoke layer in an area where the intermediate protective layer is not formed. If the thin film magnetic head is affected by ambient temperature environment, the thermal expansion suppressing layer suppresses the shift of the main magnetic pole layer and the return yoke layer toward the air bearing surface. This suppresses thermal protrusion from occurring on the thin film magnetic head due to ambient temperature environment.
    Type: Grant
    Filed: March 29, 2007
    Date of Patent: December 7, 2010
    Assignees: TDK Corporation, SAE Magnetics (H.K.) Ltd.
    Inventors: Takamitsu Sakamoto, Naoto Matono, Noriaki Kasahara, Shin Narushima, Hiromichi Umehara
  • Patent number: 7787215
    Abstract: A thin film magnetic head is provided, in which thermal protrusion can be suppressed. The thin film magnetic head includes a main magnetic pole layer which conducts a magnetic flux into the recording medium so that the recording medium is magnetized in a direction perpendicular to a surface of the recording medium, a first return yoke layer provided in a trailing side of the main magnetic pole layer, and has a recess in a top surface, a second return yoke layer provided so as to fill at least the recess of the first return yoke layer, and a thermal expansion suppression layer provided in a trailing side of the second return yoke layer. Thus, since the thermal expansion suppression layer can be provided on a surface having no recess, a possibility of a crack in the thermal expansion suppression layer can be eliminated.
    Type: Grant
    Filed: March 29, 2007
    Date of Patent: August 31, 2010
    Assignees: TDK Corporation, SAE Magnetics (H.K.) Ltd.
    Inventors: Shin Narushima, Naoto Matono, Takamitsu Sakamoto, Noriaki Kasahara, Koichi Otani
  • Patent number: 7679862
    Abstract: Embodiments of the invention secure a sufficiently large magnetic field, and deter a protrusion phenomenon of a perpendicular magnetic recording head, causing a problem in implementing a low flying height, while solving problems such as erasure of information in peripheral tracks. In one embodiment, a main pole or a stacked body made up of the main pole, and an auxiliary pole is deposited over an underlayer formed on a substrate so as to be in contact with the underlayer. On top of the main pole or the stacked body, there is deposited a coil, a return pole, and a read element in that order, thereby fabricating a perpendicular magnetic recording head.
    Type: Grant
    Filed: November 14, 2005
    Date of Patent: March 16, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kazuhiro Nakamoto, Kimitoshi Etoh, Masayuki Kurita
  • Patent number: 7649713
    Abstract: A thin-film magnetic head that has an improved protrusion efficiency under the condition of not only assuring the reliability of the-heating operation, but also stabilizing the read output is provided. The head comprises: a magnetic head element for writing and/or reading data signals; a heating element for generating heat at least during operations of the magnetic head element; and a first heatsink element provided adjacent to the heating element for receiving a part of the heat generated from the heating element, the first heatsink element being a distance from the magnetic head element.
    Type: Grant
    Filed: January 18, 2006
    Date of Patent: January 19, 2010
    Assignee: TDK Corporation
    Inventors: Norikazu Ota, Katsuki Kurihara, Hiraku Hirabayashi, Taro Oike, Hiroki Matsukuma
  • Patent number: 7551407
    Abstract: A read head comprises: a bottom shield layer; a top shield layer; an MR element disposed between the bottom shield layer and the top shield layer; a bottom shield gap film disposed between the bottom shield layer and the MR element; and a top shield gap film disposed between the top shield layer and the MR element. The MR element has a first end closer to the air bearing surface and a second end opposite to the first end. An adjacent layer made of a metal material is adjacent to the second end with an insulating film disposed in between. The material making up the adjacent layer has a linear thermal expansion coefficient whose absolute value is 6×10?6/° C. or smaller at a temperature of 30° C., and preferably 1×10?6/° C. or smaller.
    Type: Grant
    Filed: March 7, 2005
    Date of Patent: June 23, 2009
    Assignee: TDK Corporation
    Inventors: Takahiko Machita, Koji Shimazawa
  • Patent number: 7391590
    Abstract: Provided is a thin film magnetic head capable of reducing the amount of protrusion of a write shield layer, thereby preventing a collision with a recording medium, and thereby ensuring a recording operation with stability. A heat sink layer is disposed on the leading side of a thin film coil in order to dissipate heat produced by the thin film coil. When the thin film coil produces heat during the recording of information, priority is given to the guidance of the heat to the leading side of the thin film coil, namely, the side opposite to the position of the write shield layer, rather than the guidance of the heat to the trailing side of the thin film coil, namely, the position of the write shield layer, so as to dissipate the heat. Thus, the thin film magnetic head reduces the likelihood of the heat accumulating in the write shield layer, thus reduces the likelihood of the write shield layer expanding thermally, and thus reduces the amount of protrusion of the write shield layer.
    Type: Grant
    Filed: August 27, 2004
    Date of Patent: June 24, 2008
    Assignee: TDK Corporation
    Inventors: Naoto Matono, Norikazu Ota, Mitsuo Otsuki