Treating To Affect Magnetic Properties Patents (Class 29/603.08)
  • Patent number: 9537087
    Abstract: A nanoscale tunnel magneto-resistance (TMR) sensor comprising an in-plane-magnetized reference layer and a free layer comprising interfacial perpendicular anisotropy, wherein the free layer comprises a sensing layer for sensing resistance as a function of applied magnetic field and is tunable to vary the direction of the sensing layer magnetization to be in-plane, canted, or out-of-plane.
    Type: Grant
    Filed: January 27, 2015
    Date of Patent: January 3, 2017
    Assignee: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Pedram Khalili Amiri, Zhongming Zeng, Kang L. Wang
  • Patent number: 9431047
    Abstract: A method provides a magnetic transducer including a first shield, a read sensor, and a second shield. The read sensor is between the first shield and the second shield. The read sensor has at least one pinned layer aligned with a sensor pinning direction. Providing the second shield includes depositing at least one of a first ferromagnetic layer, a second ferromagnetic and a pinning layer in the presence of a first magnetic field in a first direction non-orthogonal and non-parallel to the sensor pinning direction. A nonmagnetic spacer layer is between the first ferromagnetic layer and the second ferromagnetic layer. The pinning layer is adjacent to the second ferromagnetic layer. The first ferromagnetic layer is between the read sensor and the nonmagnetic spacer layer. The first ferromagnetic layer is coupled antiparallel with the second ferromagnetic layer.
    Type: Grant
    Filed: June 25, 2013
    Date of Patent: August 30, 2016
    Assignee: WESTERN DIGITAL (FREMONT), LLC
    Inventor: Rongfu Xiao
  • Patent number: 9021685
    Abstract: An annealing process for a TMR or GMR sensor having an amorphous free layer is disclosed and employs at least two annealing steps. A first anneal at a temperature T1 of 200° C. to 270° C. and for a t1 of 0.5 to 15 hours is employed to develop the pinning in the AFM and pinned layers. A second anneal at a temperature T2 of 260° C. to 400° C. where T2>T1 and t1>t2 is used to crystallize the amorphous free layer and complete the pinning. An applied magnetic field of about 8000 Oe is used during both anneal steps. The mechanism for forming a sensor with high MR and robust pinning may involve structural change in the tunnel barrier or at an interface between two of the layers in the spin valve stack. A MgO tunnel barrier and a CoFe/CoB free layer are preferred.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: May 5, 2015
    Assignee: Headway Technologies, Inc.
    Inventors: Tong Zhao, Hui-Chuan Wang, Kunliang Zhang, Min Li
  • Patent number: 8984738
    Abstract: A manufacturing method of a slider includes steps of (a) providing a row bar with a plurality of slider elements connecting together, the row bar having an air bearing surface, a back surface opposite the air bearing surface, a bonding surface and a bottom surface opposite the bonding surface; (b) grinding the bottom surface of the row bar; (c) lapping the air bearing surface of the row bar so as to obtain a predetermined requirement, and applying a first magnetic field with a first direction during lapping the air bearing surface, and the first direction being parallel to the air bearing surface and the bonding surface; and (d) cutting the row bar into a plurality of individual sliders. The present invention can maintain a good performance of a magnetic head during the manufacturing process.
    Type: Grant
    Filed: February 22, 2012
    Date of Patent: March 24, 2015
    Assignee: SAE Magnetics (H.K.) Ltd
    Inventors: Chiuming Lueng, Mankit Lee, Lorest Garcia Pingul, Yasutoshi Fujita, Cheukman Lui, ChiYuen Mok, Cheukwing Leung, Juren Ding, Rongkwang Ni
  • Patent number: 8881376
    Abstract: A method of manufacturing a PMR writer is disclosed that minimizes pole erasure during non-writing and maximize write field during writing by including an AFM-FM phase change material spacer that is in an AFM state during non-writing and switches to a FM state by heating during writing. The main pole layer including the write pole may be formed as a laminated structure by a sputter deposition process wherein a plurality of “n” ferromagnetic layers and “n?1” AFM-FM phase change material layers are laid down in an alternating manner. The AFM-FM phase change material is preferably a FeRh or FeRhX alloy (X=Pt, Pd, or Ir) having a Rh content >35 atomic %, and may also be used as a flux gate to prevent yoke flux from leaking into the write pole tip.
    Type: Grant
    Filed: August 22, 2011
    Date of Patent: November 11, 2014
    Assignee: Headway Technologies, Inc.
    Inventors: Yuchen Zhou, Kenichi Takano, Kowang Liu, Kunliang Zhang, Liejie Guan, Moris Dovek, Joe Smyth
  • Patent number: 8813345
    Abstract: A method for manufacturing a disk drive device includes (a) assembling a sub assembly by assembling a bearing unit and a rotating body to a fixed body in a clean room, the rotating body being supported by the bearing unit in a freely rotatable manner to the fixed body, (b) cleaning the sub assembly by spraying a mixture of a cleaning liquid and a first gas to at least either one of the fixed body and the rotating body; and (c) enclosing the sub assembly using an enclosing member.
    Type: Grant
    Filed: June 11, 2012
    Date of Patent: August 26, 2014
    Assignee: Samsung Electro-Mechanics Japan Advanced Technology Co., Ltd.
    Inventors: Kenji Nishihara, Hirofumi Kajiwara
  • Publication number: 20140154529
    Abstract: A magnetic read transducer including a magnetoresistive sensor is described, as well as a fabrication method thereof. The magnetoresistive sensor includes a cap layer overlaying a free layer. The cap layer is situated with a first thickness to absorb boron from the free layer. The magnetoresistive sensor is annealed, and boron is diffused from the free layer and absorbed by the cap layer, improving the magnetic performance of the free layer. The cap layer thickness is then reduced to a second thickness, thereby reducing the shield-to-shield (SS) stack spacing of the magnetoresistive sensor and allowing for increased areal recording density.
    Type: Application
    Filed: November 30, 2012
    Publication date: June 5, 2014
    Applicant: Western Digital (Fremont), LLC
    Inventor: Western Digital (Fremont), LLC
  • Patent number: 8734620
    Abstract: A method for producing a hard bias (HB) structure that stabilizes a free layer in an adjacent spin valve is disclosed. The HB structure includes a composite seed layer and a metal layer having a fcc(111) or hcp(001) texture to enhance perpendicular magnetic anisotropy (PMA) in an overlying (Co/Ni)x laminate. (Co/Ni)x deposition involves low power and high Ar pressure to avoid damaging Co/Ni interfaces and thereby preserves PMA. A capping layer is formed on the HB layer to protect against etchants in subsequent processing. After initialization, HB magnetization direction is perpendicular to the sidewalls of the spin valve and generates an Mrt value that is greater than from an equivalent thickness of CoPt. A non-magnetic metal separation layer may be formed on the capping layer and spin valve to provide an electrical connection between top and bottom shields.
    Type: Grant
    Filed: October 8, 2013
    Date of Patent: May 27, 2014
    Assignee: Headway Technologies, Inc.
    Inventors: Zhang Kunliang, Li Min, Zhou Yuchen, Zheng Min
  • Patent number: 8705212
    Abstract: An apparatus and associated method may be used to produce a magnetic element capable of detecting changes in magnetic states. Various embodiments of the present invention are generally directed to a magnetically responsive lamination of layers with a first portion and a laterally adjacent second portion. The second portion having a predetermined roughness between at least two layers capable of producing orange-peel coupling.
    Type: Grant
    Filed: April 25, 2011
    Date of Patent: April 22, 2014
    Assignee: Seagate Technology LLC
    Inventors: Jason Bryce Gadbois, Michael Christopher Kautzky, Mark William Covington, Dian Song, Dimitar Velikov Dimitrov, Qing He, Wei Tian, Thomas Boonstra, Sunita Gangopadhyay
  • Publication number: 20130308228
    Abstract: A magnetic sensor having reduced read gap thickness, reduced signal noise and improved signal to noise ratio. The sensor includes a sensor stack and hard bias structures formed at either side of the sensor stack for biasing the free layer of the sensor. A protective layer is formed over a portion of the hard bias structure, however a portion of the hard bias structure extends upward toward the upper shield and is disposed between the protective layer and the sensor stack as a result of the process used to form the magnetic bias structure. This portion of the hard bias structure that extends toward the upper shield has a reduced magnetization relative to the rest of the hard bias structure so that it will not magnetically couple with the upper shield.
    Type: Application
    Filed: May 15, 2012
    Publication date: November 21, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hideki Mashima, Nobuo Yoshida, Takahiro Ibusuki, Tsutomu Yasuda
  • Patent number: 8564282
    Abstract: There is provided an angle sensor and angle detection device of high output and high accuracy with a wide operating temperature range. First through eighth sensor units 511, 522, 523, 514, 531, 542, 543 and 534 are produced from spin valve magnetoresistive films that use a self-pinned type ferromagnetic pinned layer comprising two layers of ferromagnetic films that are strongly and anti-ferromagnetically coupled. The respective sensor units are produced via the formation and patterning of thin-films magnetized at angles that differ by 90°, and the formation of insulation films. By using, for the ferromagnetic films, CoFe and FeCo films that have similar Curie temperatures to make the difference in magnetization amount be zero, high immunity to external magnetic fields, a broad adaptive temperature range, and high output are realized.
    Type: Grant
    Filed: December 3, 2008
    Date of Patent: October 22, 2013
    Assignee: Hitachi Metals, Ltd.
    Inventors: Hiroyuki Hoshiya, Kenichi Meguroo, Kazuhiro Nakamoto, Yasunori Abe
  • Patent number: 8552328
    Abstract: The invention provides a method for fixing up the deterioration of a magneto-resistive effect device. A hard disk system is provided in it with a head heating means for heating a thin-film magnetic head, and by that head heating means, a defective site of the magneto-resistive effect device, which occurs as the hard disk system is in operation and is confined in a quasi-stable state, is fixed up in such a way as to return back to its own normal stable state. Thus, the deteriorated site of the magneto-resistive effect device (reproducing device) in the thin-film magnetic head, which is caused by the so-called thermal asperity as the hard disk system is in operation, is fixed up while it remains built in the hard disk system, i.e., without dismantling the hard disk system.
    Type: Grant
    Filed: December 28, 2007
    Date of Patent: October 8, 2013
    Assignee: TDK Corporation
    Inventors: Takumi Yanagisawa, Yosuke Antoku, Yoshikazu Sawada
  • Publication number: 20130212871
    Abstract: A manufacturing method of a slider includes steps of (a) providing a row bar with a plurality of slider elements connecting together, the row bar having an air bearing surface, a back surface opposite the air bearing surface, a bonding surface and a bottom surface opposite the bonding surface; (b) grinding the bottom surface of the row bar; (c) lapping the air bearing surface of the row bar so as to obtain a predetermined requirement, and applying a first magnetic field with a first direction during lapping the air bearing surface, and the first direction being parallel to the air bearing surface and the bonding surface; and (d) cutting the row bar into a plurality of individual sliders. The present invention can maintain a good performance of a magnetic head during the manufacturing process.
    Type: Application
    Filed: February 22, 2012
    Publication date: August 22, 2013
    Applicant: SAE Magnetics (H.K.) Ltd.
    Inventors: Chiuming Lueng, Mankit Lee, Lorest Garcia Pingul, Yasutoshi Fujita, Cheukman Lui, ChiYuen Mok, Cheukwing Leung, Juren Ding, Rongkwang Ni
  • Patent number: 8490279
    Abstract: A method of forming a hard bias (HB) structure for longitudinally biasing a free layer in a MR sensor is disclosed. A HB layer is formed with easy axis growth perpendicular to an underlying seed layer which is formed above a substrate and along two sidewalls of the sensor. In one embodiment, a conformal soft magnetic layer that may be a top shield is deposited on the HB layer to provide direct exchange coupling that compensates HB surface charges. Optionally, a thin capping layer on the HB layer enables magneto-static shield-HB coupling. After HB initialization, HB regions along the sensor sidewalls have magnetizations that are perpendicular to the sidewalls as a result of surface charges near the seed layer. Sidewalls may be extended into the substrate (bottom shield) to give enhanced protection against side reading.
    Type: Grant
    Filed: September 24, 2010
    Date of Patent: July 23, 2013
    Assignee: Headway Technologies, Inc.
    Inventors: Yuchen Zhou, Kenichi Takano, Kunliang Zhang
  • Patent number: 8470092
    Abstract: A method (and structure) of thermally treating a magnetic layer of a wafer, includes annealing, for a predetermined short duration, a magnetic layer of a single wafer.
    Type: Grant
    Filed: August 19, 2008
    Date of Patent: June 25, 2013
    Assignee: International Business Machines Corporation
    Inventors: Ulrich Karl Klostermann, Wolfgang Raberg, Philip Trouilloud
  • Patent number: 8456781
    Abstract: A composite free layer having a FL1/insertion/FL2 configuration where a top surface of FL1 is treated with a weak plasma etch is disclosed for achieving enhanced dR/R while maintaining low RA, and low ? in TMR or GMR sensors. The weak plasma etch removes less than about 0.2 Angstroms of FL1 and is believed to modify surface structure and possibly increase surface energy. FL1 may be CoFe, CoFe/CoFeB, or alloys thereof having a (+) ? value. FL2 may be CoFe, NiFe, or alloys thereof having a (?) ? value. The thin insertion layer includes at least one magnetic element such as Co, Fe, and Ni, and at least one non-magnetic element. When CoFeBTa is selected as insertion layer, the CoFeB:Ta ratio is from 1:1 to 4:1.
    Type: Grant
    Filed: July 30, 2012
    Date of Patent: June 4, 2013
    Assignee: Headway Technologies, Inc.
    Inventors: Tong Zhao, Hui-Chuan Wang, Min Li, Kunliang Zhang
  • Patent number: 8351163
    Abstract: According to one embodiment, a method for producing a Tunneling Magnetoresistance (TMR) read head includes forming a fixed layer, forming an insulating barrier layer above the fixed layer, forming a free layer above the insulating barrier layer, and annealing the free layer, the fixed layer, and the insulating barrier layer. The fixed layer includes a first ferromagnetic layer having a CoxFe (0?x?15) interface layer and a Co-based amorphous metallic layer between the CoxFe interface layer and the insulating barrier layer, an antiparallel coupling layer below the first ferromagnetic layer, and a second ferromagnetic layer below the antiparallel coupling layer. In another embodiment, a TMR read head includes the layers described above, and may be included in a magnetic data storage system.
    Type: Grant
    Filed: November 17, 2010
    Date of Patent: January 8, 2013
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Koji Sakamoto, Koichi Nishioka
  • Patent number: 8312617
    Abstract: A method of manufacturing a disk drive device including: assembling a subassembly by fixing at least a bearing unit, a drive unit and a hub to a base member in a first clean room; cleaning the subassembly in a second clean room; and sealing the subassembly by a sealing member. The first clean room and the second clean room are communicated with each other by a communicating opening for transferring the subassembly, and an atmospheric pressure in the second clean room is equal to or higher than that in the first clean room.
    Type: Grant
    Filed: September 17, 2009
    Date of Patent: November 20, 2012
    Assignee: Alphana Technology Co., Ltd.
    Inventors: Yuji Omura, Kenji Nishihara
  • Patent number: 8274811
    Abstract: A spin transfer oscillator (STO) structure is disclosed that includes two assist layers with perpendicular magnetic anisotropy (PMA) to enable a field generation layer (FGL) to achieve an oscillation state at lower current density for MAMR applications. In one embodiment, the STO is formed between a main pole and write shield and the FGL has a synthetic anti-ferromagnetic structure. The STO configuration may be represented by seed layer/spin injection layer (SIL)/spacer/PMA layer 1/FGL/spacer/PMA layer 2/capping layer. The spacer may be Cu for giant magnetoresistive (GMR) devices or a metal oxide for tunneling magnetoresistive (TMR) devices. Alternatively, the FGL is a single ferromagnetic layer and the second PMA assist layer has a synthetic structure including two PMA layers with magnetic moment in opposite directions in a seed layer/SIL/spacer/PMA assist 1/FGL/spacer/PMA assist 2/capping layer configuration. SIL and PMA assist layers are laminates of (CoFe/Ni)x or the like.
    Type: Grant
    Filed: November 22, 2010
    Date of Patent: September 25, 2012
    Assignee: Headway Technologies, Inc.
    Inventors: Kunliang Zhang, Min Li, Yuchen Zhou
  • Patent number: 8259420
    Abstract: A composite free layer having a FL1/insertion/FL2 configuration where a top surface of FL1 is treated with a weak plasma etch is disclosed for achieving enhanced dR/R while maintaining low RA, and low ? in TMR or GMR sensors. The weak plasma etch removes less than about 0.2 Angstroms of FL1 and is believed to modify surface structure and possibly increase surface energy. FL1 may be CoFe, CoFe/CoFeB, or alloys thereof with Ni, Ta, Mn, Ti, W, Zr, Hf, Tb, or Nb having a (+) ? value. FL2 may be CoFe, NiFe, or alloys thereof having a (?) ? value. The thin insertion layer includes at least one magnetic element such as Co, Fe, and Ni, and at least one non-magnetic element selected from Ta, Ti, W, Zr, Hf, Nb, Mo, V, Cr, or B. When CoFeBTa is selected as insertion layer, the CoFeB:Ta ratio is from 1:1 to 4:1.
    Type: Grant
    Filed: February 1, 2010
    Date of Patent: September 4, 2012
    Assignee: Headway Technologies, Inc.
    Inventors: Tong Zhao, Hui Chuan Wang, Min Li, Kunliang Zhang
  • Publication number: 20110308074
    Abstract: A PMR writer is disclosed that minimizes pole erasure during non-writing and maximize write field during writing through an AFM-FM phase change material that is in an AFM state during non-writing and switches to a FM state by heating during writing. The main pole layer including the write pole may be comprised of a laminated structure having a plurality of “n” ferromagnetic layers and “n?1” AFM-FM phase change material layers arranged in an alternating manner. The AFM-FM phase change material is preferably a FeRh or FeRhX alloy (X=Pt, Pd, or Ir) having a Rh content>35 atomic %. AFM-FM phase change material may also be used as a flux gate to prevent yoke flux from leaking into the write pole tip. Heating for the AFM to FM transition is provided by write coils and/or a coil located near the AFM-FM phase change material to enable faster transition times.
    Type: Application
    Filed: August 22, 2011
    Publication date: December 22, 2011
    Inventors: Yuchen Zhou, Kenichi Takano, Kowang Liu, Kunliang Zhang, Liejie Guan, Moris Dovek, Joe Smyth
  • Publication number: 20110235216
    Abstract: A read head having an improved longitudinal bias stack for stabilizing the sense layer structure of a CPP read sensor is proposed. The longitudinal bias stack is separated by an insulation layer from the CPP read sensor in each of two side regions, and is sandwiched together with the insulation layer and the CPP read sensor between lower and upper ferromagnetic shields in the read head. In a preferred embodiment of the invention, the longitudinal bias stack mainly comprises an Fe—Pt longitudinal bias layer without any seed layers, and thus the thickness of the insulation layer alone defines a spacing between the Fe—Pt longitudinal bias layer and the CPP read sensor. Since the Fe—Pt longitudinal bias layer without any seed layers exhibits good in-plane hard-magnetic properties after annealing and the spacing is narrow, the stabilization scheme is effective.
    Type: Application
    Filed: March 26, 2010
    Publication date: September 29, 2011
    Inventor: Tsann Lin
  • Patent number: 7934309
    Abstract: The method of fabricating an exchange-coupling film in accordance with the present invention comprises a multilayer body forming step of forming a multilayer body having an antiferromagnetic layer and a ferromagnetic layer laminated on the antiferromagnetic layer; and an annealing step of annealing the multilayer body in a magnetic field with a maximum temperature higher than a blocking temperature of the multilayer body by 15 to 60° C.
    Type: Grant
    Filed: December 26, 2007
    Date of Patent: May 3, 2011
    Assignee: TDK Corporation
    Inventors: Keita Kawamori, Satoshi Miura
  • Patent number: 7891081
    Abstract: A process is described for the fabrication of a magnetic read head in which contact between the pinned layer and the AFM is limited to their edges. The principal steps are to deposit an antiferromagnetic layer and to then pattern it into a pair of antiferromagnetic layers separated by no more than about 2 microns. A layer of magnetic material that lies between, and is in contact with, said antiferromagnetic layers is then deposited, following which the layer of magnetic material is magnetized.
    Type: Grant
    Filed: April 1, 2004
    Date of Patent: February 22, 2011
    Assignee: Headway Technologies, Inc.
    Inventor: Glen Garfunkel
  • Publication number: 20110013317
    Abstract: A method and system for providing a magnetic transducer are disclosed. The method and system include providing a magnetic element that includes a free layer, a pinned layer, and a nonmagnetic spacer layer between the free layer and the pinned layer. The nonmagnetic spacer layer is a tunneling barrier layer. The free layer is configured to be biased in a first direction. The pinned layer has a pinned layer magnetization configured to be pinned in a second direction that is at a first angle from perpendicular to the ABS. The first angle is nonzero and different from ninety degrees. The second direction and the first direction form a second angle that is different from ninety degrees.
    Type: Application
    Filed: July 16, 2009
    Publication date: January 20, 2011
    Applicant: WESTERN DIGITAL (FREMONT), LLC
    Inventors: CHRISTIAN KAISER, LAURENCE L. CHEN, QUNWEN LENG
  • Patent number: 7870660
    Abstract: A magnetic head includes: an encasing layer made of a nonmagnetic material and having a groove that opens in the top surface; a nonmagnetic metal layer made of a nonmagnetic metal material, disposed on the top surface of the encasing layer, and having a penetrating opening that is contiguous to the groove; and a pole layer made of a magnetic metal material and encased in the groove of the encasing layer and in the opening of the nonmagnetic metal layer. The pole layer has an end face located in a medium facing surface, the end face having a first portion and a second portion that is located farther from a substrate than the first portion and connected to the first portion. The first portion has a width that decreases as the distance from the substrate decreases. The second portion has a uniform width that defines the track width. In the medium facing surface, the nonmagnetic metal layer exists on both sides of the second portion, the sides being opposed to each other in the direction of track width.
    Type: Grant
    Filed: February 11, 2009
    Date of Patent: January 18, 2011
    Assignee: Headway Technologies, Inc.
    Inventors: Yoshitaka Sasaki, Hiroyuki Itoh, Hironori Araki, Takehiro Horinaka, Shigeki Tanemura
  • Patent number: 7805828
    Abstract: A method of manufacturing a thin-film magnetic head including forming the first shield layer; forming the magnetoresistive device, carried out after forming the first shield layer, a heat treatment providing exchange coupling between the ferromagnetic layer and the antiferromagnetic layer so as to magnetize the ferromagnetic layer in a predetermined direction; forming the domain control layer so as to hold the magnetoresistive device in a track width direction; magnetizing the domain control layer in a direction yielding a magnetic field in the same direction as with a magnetic field received by the ferromagnetic layer upon exchange-coupling with the antiferromagnetic layer, forming the second shield layer, carried out after magnetizing the domain control layer, and remagnetizing the domain control layer in a direction yielding the longitudinal bias magnetic field, carried out after forming the second shield layer.
    Type: Grant
    Filed: May 23, 2007
    Date of Patent: October 5, 2010
    Assignee: TDK Corporation
    Inventors: Koji Shimazawa, Yoshihiro Tsuchiya
  • Patent number: 7716814
    Abstract: Components of a plurality of magnetic heads are formed on a single substrate to fabricate a magnetic head substructure in which a plurality of pre-head portions are aligned in a plurality of rows. The substructure is cut to separate the plurality of pre-head portions from one another, and the plurality of magnetic heads are thereby fabricated. The surface formed by cutting the substructure is lapped to form a lapped surface. The lapped surface is lapped so as to reach a target position of a medium facing surface. The substructure incorporates first to fourth resistor elements each of which detects the position of the lapped surface. The third and fourth detection elements are located at positions shifted from the first and second resistor elements along the direction orthogonal to the medium facing surface.
    Type: Grant
    Filed: February 5, 2007
    Date of Patent: May 18, 2010
    Assignees: Headway Technologies, Inc., SAE Magnetics (H.K.) Ltd.
    Inventors: Yoshitaka Sasaki, Hiroyuki Itoh, Kazuo Ishizaki, Ryuji Fujii, Tatsushi Shimizu
  • Patent number: 7650686
    Abstract: A servo track writer (STW) clockhead radius jig is disclosed. One embodiment provides a hard disk drive assembly including a base having a cutaway portion to provide visual access therein. In addition, a disk is mounted in the hard disk drive assembly, this disk having an indicator thereon to indicate a required radius setting for a clockhead.
    Type: Grant
    Filed: December 28, 2007
    Date of Patent: January 26, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Teodosio Quilapquilap
  • Patent number: 7596853
    Abstract: The method of manufacturing a thin film magnetic head includes forming a first recessed portion for insulation and a second recessed portion for contact that reach the substrate through the first insulating layer from a side of the first insulating layer of the substrate having the first insulating layer thereon; forming a second insulating layer on the substrate in the first recessed portion; and forming the lower shield layer in the first recessed portion and a contact portion in the second recessed portion.
    Type: Grant
    Filed: December 28, 2006
    Date of Patent: October 6, 2009
    Assignee: TDK Corporation
    Inventors: Kenji Ichinohe, Yosuke Goto
  • Publication number: 20090229111
    Abstract: An annealing process for a TMR or GMR sensor having an amorphous free layer is disclosed and employs at least two annealing steps. A first anneal at a temperature T1 of 200° C. to 270° C. and for a t1 of 0.5 to 15 hours is employed to develop the pinning in the AFM and pinned layers. A second anneal at a temperature T2 of 260° C. to 400° C. where T2>T1 and t1>t2 is used to crystallize the amorphous free layer and complete the pinning. An applied magnetic field of about 8000 Oe is used during both anneal steps. The mechanism for forming a sensor with high MR and robust pinning may involve structural change in the tunnel barrier or at an interface between two of the layers in the spin valve stack. A MgO tunnel barrier and a CoFe/CoB free layer are preferred.
    Type: Application
    Filed: March 12, 2008
    Publication date: September 17, 2009
    Inventors: Tong Zhao, Hui-Chuan Wang, Kunliang Zhang, Min Li
  • Publication number: 20090151151
    Abstract: Methods of fabricating magnetic read heads are provided which reduce the width of the scratch exposure region of a read head. During normal fabrication processes, a read head is formed with a first shield, a read element formed on the first shield, and hard bias layers formed on either side of the read element. The width of the read elements and the hard bias layers define an initial scratch exposure region. According to embodiments herein, a mask structure is formed to protect the read element and first portions of the hard bias layers proximate to the read element. A removal process is then performed to remove second portions of the hard bias layers that are not protected by the mask structure, which defines a final scratch exposure region that is smaller than the initial scratch exposure region.
    Type: Application
    Filed: December 16, 2007
    Publication date: June 18, 2009
    Inventors: David P. Druist, Mohamad T. Krounbi, David J. Seagle
  • Patent number: 7536778
    Abstract: A method of fabrication is disclosed for a slider having sites for fabrication of a continuous coil having a set of front coils and a set of back coils and a center tab, where the slider includes underpass leads.
    Type: Grant
    Filed: September 5, 2007
    Date of Patent: May 26, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Amanda Baer, Tsung Yuan Chen, David Patrick Druist, Edward Hin Pong Lee
  • Patent number: 7536772
    Abstract: A method is given for the manufacture of a bottom spin valve (BSV) spin filter spin valve (SFSV) type read sensor. The sensor has a composite, ultra-thin (<20 Angstroms) laminated free layer formed as a Cu high conductance layer (HCL) between two layers of CoFe. A second HCL is formed as a layer of Ru on the composite free layer. By adjusting the thicknesses of the two HCL's, the free layer will have low coercivity and tunable magnetostriction. The sensor is capable of reading densities exceeding 60 Gb/in2.
    Type: Grant
    Filed: November 8, 2005
    Date of Patent: May 26, 2009
    Assignee: Headway Technologies, Inc.
    Inventors: Cheng T. Horng, Ru-Ying Tong
  • Patent number: 7506432
    Abstract: A lower shield layer is formed by being embedded in a first recess formed in an under layer. Accordingly, the distance between the lower shield layer and a slider can be reduced. Also, a second metal layer is formed from above a gap layer covering an electrode extracting layer over above the under layer hindwards therefrom. Accordingly, the second metal layer can be brought closer to the slider side than an upper shield layer. Consequently, the thermal dissipation effects of the thin-film magnetic head can be improved.
    Type: Grant
    Filed: May 15, 2007
    Date of Patent: March 24, 2009
    Assignee: TDK Corporation
    Inventors: Kiyoshi Sato, Hideki Gochou, Hisayuki Yazawa
  • Patent number: 7497007
    Abstract: A high performance TMR element is fabricated by inserting an oxygen surfactant layer (OSL) between a pinned layer and AlOx tunnel barrier layer in a bottom spin valve configuration. The pinned layer preferably has a SyAP configuration with an outer pinned layer, a Ru coupling layer, and an inner pinned layer comprised of CoFeXBY/CoFeZ wherein x=0 to 70 atomic %, y=0 to 30 atomic %, and z=0 to 100 atomic %. The OSL is formed by treating the CoFez layer with oxygen plasma. The AlOx tunnel barrier has improved uniformity of about 2% across a 6 inch wafer and can be formed from an Al layer as thin as 5 Angstroms. As a result, the Hin value can be decreased by ? to about 32 Oe. A dR/R of 25% and a RA of 3 ohm-cm2 have been achieved for TMR read head applications.
    Type: Grant
    Filed: July 14, 2005
    Date of Patent: March 3, 2009
    Assignee: Headway Technologies, Inc.
    Inventors: Hui-Chuan Wang, Tong Zhao, Min Li, Kunliang Zhang
  • Patent number: 7444738
    Abstract: Methods and apparatus are provided for sensing physical parameters. The apparatus comprises a magnetic tunnel junction (MTJ) and a magnetic field source whose magnetic field overlaps the MTJ and whose proximity to the MTJ varies in response to an input to the sensor. A magnetic shield is provided at least on a face of the MFS away from the MTJ. The MTJ comprises first and second magnetic electrodes separated by a dielectric configured to permit significant tunneling conduction therebetween. The first magnetic region has its spin axis pinned and the second magnetic electrode has its spin axis free. The magnetic field source is oriented closer to the second magnetic electrode than the first magnetic electrode. The overall sensor dynamic range is extended by providing multiple electrically coupled sensors receiving the same input but with different individual response curves and desirably but not essentially formed on the same substrate.
    Type: Grant
    Filed: July 29, 2005
    Date of Patent: November 4, 2008
    Assignee: EverSpin Technologies, Inc.
    Inventors: Young Sir Chung, Robert W. Baird, Gregory W. Grynkewich
  • Patent number: 7441324
    Abstract: A method is provided for preserving the transverse biasing of a GMR (or MR) read head during back-end processing. In a first preferred embodiment, the method comprises magnetizing the longitudinal biasing layers of the read head in a transverse direction, so that the resulting field at the position of the transverse biasing layer places it in a minimum of potential energy which stabilizes its direction. The field of the longitudinal biasing layer is then reset to the longitudinal direction in a manner which maintains the transverse biasing direction. In a second embodiment, a novel fixture for mounting the read head during processing includes a magnetic portion which stabilizes the transverse bias of the read head. The two methods may be used singly or in combination.
    Type: Grant
    Filed: July 5, 2005
    Date of Patent: October 28, 2008
    Assignee: Headway Technologies, Inc.
    Inventors: Yimin Guo, Li-Yan Zhu
  • Patent number: 7389575
    Abstract: There is disclosed a method of manufacturing a plurality of removable permanently magnetized elements from a substrate comprising ferrite material. The method prints symbol images on the substrate with an offset, automatic sheet-fed press, and die cuts the symbol images on the substrate with an automatic sheet-fed die cutter to form a plurality of elements forming portions of the substrate. Thereafter, the method magnetizes the ferrite material to permanently magnetize the substrate and form the plurality of permanently magnetized elements. The method reduces wastage, permits for improved substrate registration, more accurate symbol placement on the substrate, higher production speeds, and reduced labor costs.
    Type: Grant
    Filed: June 30, 2005
    Date of Patent: June 24, 2008
    Inventors: Ernest Ross Barlett, Donna Darlene Barlett
  • Patent number: 7370404
    Abstract: A spin valve sensor in a read head has a spacer layer which is located between a self-pinned AP pinned layer structure and a free layer structure. The free layer structure is longitudinally stabilized by first and second hard bias layers which abut first and second side surfaces of the spin valve sensor. The AP pinned layer structure has an antiparallel coupling layer (APC) which is located between first and second AP pinned layers (AP1) and (AP2). The invention employs a resetting process for setting of the magnetic moments of the AP pinned layers by applying a field at an acute angle to the head surface in a plane parallel to the major planes of the layers of the sensor. The resetting process sets a proper polarity of each AP pinned layer, which polarity conforms to processing circuitry employed with the spin valve sensor.
    Type: Grant
    Filed: May 28, 2004
    Date of Patent: May 13, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hardayal Singh Gill, Jinshan Li, Kenneth Donald Mackay, Kouichi Nishioka, Andy Cuong Tran
  • Publication number: 20080052896
    Abstract: A free layer functions such that a magnetization direction changes depending on an external magnetic field, and is made up of a multilayer structure including a first Heusler alloy layer, and a fixed magnetization layer takes a form wherein an inner pin layer and an outer pin layer are stacked one upon another with a nonmagnetic intermediated layer sandwiched between them. The inner pin layer is made up of a multilayer structure including a second Heusler alloy layer. The first and second Heusler alloy layers are each formed by a co-sputtering technique using a split target split into at least two sub-targets in such a way as to constitute a Heusler alloy layer composition. When the Heusler alloy layer is formed, therefore, it is possible to bring up a film-deposition rate, improve productivity, and improve the performance of the device.
    Type: Application
    Filed: June 1, 2007
    Publication date: March 6, 2008
    Applicant: TDK CORPORATION
    Inventors: Yoshihiro TSUCHIYA, Tomohito Mizuno, Koji Shimazawa
  • Patent number: 7332099
    Abstract: A method for reducing noise in a lapping guide. Selected portions of a magnetoresistive device wafer are bombarded with ions such that a magnetoresistive effect of lapping guides is reduced. The device is lapped, using the lapping guides to measure an extent of the lapping.
    Type: Grant
    Filed: October 6, 2005
    Date of Patent: February 19, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Mark A. Church, Wipul Pemsiri Jayasekara, Howard Gordon Zolla
  • Patent number: 7325295
    Abstract: Two embodiments of a GMR sensor of the bottom spin valve (BSV) spin filter spin valve (SFSV) type are provided together with methods for their fabrication. In each embodiment the sensor includes an in-situ naturally oxidized specularly reflecting layer (NOL) which is a more uniform and dense layer than such layers formed by high temperature annealing or reactive-ion etching. In one embodiment, the sensor has an ultra thin composite free layer and a high-conductance layer (HCL), providing high output and low coercivity. In a second embodiment, along with the same NOL, the sensor has a laminated free layer which includes a non-magnetic conductive layer, which also provides high output and low coercivity. The sensors are capable of reading densities exceeding 60 Gb/in2.
    Type: Grant
    Filed: March 27, 2006
    Date of Patent: February 5, 2008
    Assignee: Headway Technologies, Inc.
    Inventors: Cheng T. Horng, Ru-Ying Tong
  • Patent number: 7323067
    Abstract: A method of manufacturing a magneto-resistance effect type head that includes an element portion of magneto-resistance effect type and reproduces a read signal of data from a recording medium by the element portion, is proposed. The method includes applying a predetermined DC current to the element portion; and performing heat treatment on a part of the element portion that has been thermally deformed due to application of the DC current.
    Type: Grant
    Filed: February 24, 2004
    Date of Patent: January 29, 2008
    Assignee: Fujitsu Limited
    Inventor: Kenrou Yamamoto
  • Publication number: 20080010811
    Abstract: Various embodiments of the present invention pertain to manufacturing pre-sliders by annealing to saturation. According to one embodiment, pre-sliders are lapped to prepare for air bearing surfaces for the pre-sliders. The pre-sliders are annealed to saturation to level off the amount of overcoat expansion for the pre-sliders.
    Type: Application
    Filed: July 14, 2006
    Publication date: January 17, 2008
    Inventors: Damaris Davis, Hardayal S. Gill, Kenneth D. Mackay, Xiao Z. Wu
  • Patent number: 7313856
    Abstract: A manufacturing method for a spin valve sensor with a thin antiferromagnetic (AFM) layer exchange coupled to a self-pinned antiparallel coupled bias layer in the lead overlap regions is provided. The spin valve sensor comprises forming a ferromagnetic bias layer antiparallel coupled to a free layer in first and second passive regions where first and second lead layers overlap the spin valve sensor layers and forming a thin AFM layer exchange coupled to the bias layer to provide a pinning field to the bias layer. A cap layer is deposited over the thin AFM layer.
    Type: Grant
    Filed: September 29, 2005
    Date of Patent: January 1, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Hardayal Singh Gill
  • Patent number: 7284316
    Abstract: A method for forming a hard bias structure in a magnetoresistive sensor is disclosed. A magnetoresistive sensor having a soft magnetic bias layer, spacer layer, and a magnetoresistive layer, is formed over a substrate having a gap layer. A mask is formed over a portion of the magnetoresistive sensor structure to define a central region. The masked structure is ion milled to remove portions not shielded by the mask, to form the central region with sloped sides, and to expose a region of the gap layer laterally adjacent the sloped sides. A first underlayer is deposited onto at least the sloped sides at a high deposition angle. A second underlayer is deposited to at least partially overlap the first underlayer, and at a first lower deposition angle. A hard bias layer is deposited over at least a portion of the second underlayer, and at a second lower deposition angle.
    Type: Grant
    Filed: November 17, 2004
    Date of Patent: October 23, 2007
    Assignee: Western Digital (Fremont), LLC
    Inventors: Yiming Huai, Jinqiu Zhang, Jing Zhang
  • Patent number: 7275302
    Abstract: A method of forming a disc pack for use in a disc drive is provided. The method includes forming at least one alignment feature between an inner diameter and an outer diameter of each of a plurality of discs. The at least one alignment feature of a first disc of the plurality of discs and the at least one alignment feature of a second disc of the plurality of discs are utilized to substantially vertically align servo patterns on the first disc with servo patterns on the second disc. A disc pack having discs that include alignment features for aligning servo patterns on the discs is also provided.
    Type: Grant
    Filed: December 9, 2003
    Date of Patent: October 2, 2007
    Assignee: Seagate Technology LLC
    Inventor: Hwaliang Ng
  • Patent number: 7275304
    Abstract: A hard bias (HB) structure for biasing a free layer in a MR sensor within a magnetic read head is comprised of a main biasing layer with a large negative magnetostriction (?S) value. Compressive stress in the device after lapping induces a strong in-plane anisotropy that effectively provides a longitudinal bias to stabilize the sensor. The main biasing layer is formed between two FM layers, and at least one AFM layer is disposed above the upper FM layer or below the lower FM layer. Additionally, there may be a Ta/Ni or Ta/NiFe seed layer as the bottom layer in the HB structure. Compared with a conventional abutted junction exchange bias design, the HB structure described herein results in higher output amplitude under similar asymmetry sigma and significantly decreases sidelobe occurrence. Furthermore, smaller MRWu with a similar track width is achieved since the main biasing layer acts as a side shield.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: October 2, 2007
    Assignee: Headway Technologies, Inc.
    Inventors: Masanori Sakai, Kunliang Zhang, Kenichi Takano, Chyu-Jiuh Torng, Yunfei Li, Po-Kang Wang
  • Patent number: 7248445
    Abstract: A magnetic sensing element includes a composite film, a lower shield layer, and a lower electrode layer and an upper electrode layer for supplying a current perpendicular to the composite film. The composite film has an antiferromagnetic layer, a pinned magnetic layer, a nonmagnetic layer, and a free magnetic layer. The composite film has a top face and two side faces in a track width direction. Each of the two side faces has a bent position. The angle defined by the side face below the bent position and the top face is larger than the angle defined by the side face above the bent position and the top face. The bent portion preferably lies on the lower electrode layer or the lower shield layer.
    Type: Grant
    Filed: September 11, 2002
    Date of Patent: July 24, 2007
    Assignee: Alps Electric Co., Ltd.
    Inventor: Yoshihiro Nishiyama