Magnetic Layers Separated By Nonmagnetic (antiferromagnetic, Cu, Dielectric, Etc.) Layer(s) Patents (Class 428/828)
  • Patent number: 11810605
    Abstract: Various apparatuses, systems, methods, and media are disclosed to provide a magnetic recording medium with a tungsten (W) pre-seed layer. The W pre-seed layer has a higher conductance than a CrTi pre-seed layer with a similar thickness. In one embodiment, the W pre-seed layer is made of about 95 atomic percent or more of W. The W pre-seed layer has lower electrical resistivity than the CrTi pre-seed layer. As a result, the thickness of the W pre-seed layer can be reduced as compared to the thickness of a CrTi pre-seed layer if a similar conductance is to be achieved. The magnetic recording materials deposited on top of the W pre-seed layer with the reduced thickness provide comparable crystallographic orientation and recording performance to those deposited on top of a thicker CrTi pre-seed layer with a similar conductance.
    Type: Grant
    Filed: September 29, 2021
    Date of Patent: November 7, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventor: Kai Tang
  • Patent number: 11373674
    Abstract: An information processing device includes a generation unit that generates a hierarchy of a group that classifies each piece of data from information about each of a plurality of pieces of data to be recorded, and a control unit that controls recording of the plurality of pieces of data included in a group of the hierarchy at a highest level on a magnetic recording medium in a recording order according to an order from an upper hierarchy to a lower hierarchy, for each group of the hierarchy at the highest level. The magnetic recording medium has a magnetic layer containing a ferromagnetic powder and a binding agent on a non-magnetic support. A difference between spacings S0.5 and S13.5 measured under pressures of 0.5 atm and 13.5 atm by an optical interference method after n-hexane cleaning on a surface of the magnetic layer is equal to or less than 3.0 nm.
    Type: Grant
    Filed: August 4, 2021
    Date of Patent: June 28, 2022
    Assignee: FUJIFILM CORPORATION
    Inventors: Eiki Ozawa, Michitaka Kondo, Kentaro Miyamoto, Naoki Sano
  • Patent number: 11271148
    Abstract: A domain wall type magnetic recording element includes a first ferromagnetic layer containing a ferromagnetic material, a magnetic recording layer extending in a first direction which intersects a lamination direction of the first ferromagnetic layer and containing a magnetic domain wall, and a nonmagnetic layer sandwiched between the first ferromagnetic layer and the magnetic recording layer, in which the magnetic recording layer includes a recessed part or a protruding part, which is configured to trap the magnetic domain wall, on a side surface, and a width of the first ferromagnetic layer is smaller than a smallest width of the magnetic recording layer in a second direction perpendicular to the first direction in a plan view from the lamination direction.
    Type: Grant
    Filed: October 26, 2017
    Date of Patent: March 8, 2022
    Assignee: TDK CORPORATION
    Inventors: Tetsuhito Shinohara, Tomoyuki Sasaki
  • Patent number: 11120829
    Abstract: A magnetic recording medium with a reduced average grain diameter and reduced grain diameter dispersion is provided. A magnetic recording medium having a magnetic property (magnetic anisotropy energy) applicable as a magnetic recording medium is provided. It is a magnetic recording medium containing a substrate, a grain diameter control layer, a first seed layer, a second seed layer, and a magnetic recording layer containing an ordered alloy in this order, in which the second seed layer is composed of crystal grains having TiN as a main component, and a grain boundary material having at least one or more selected from the group consisting of metal oxides and carbon as a main component.
    Type: Grant
    Filed: February 27, 2019
    Date of Patent: September 14, 2021
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Hiroyasu Kataoka, Tsuyoshi Yoshizawa, Tomohiro Moriya, Shinji Uchida, Hirohisa Oyama, Takehito Shimatsu
  • Patent number: 10944339
    Abstract: The invention includes miniature dots, miniature disks or miniature cylinders and methods of making the same by dispersing a particle in or on a dissolvable, meltable or etchable layer on a substrate, a portion of the particle exposed above a surface of the dissolvable, meltable or etchable layer; depositing a mask on the particles and the dissolvable substrate; removing the particles from the layer; etching an array of nanoholes in the substrate; depositing one or more metallic layers into the nanoholes to form an array of dots, disks or cylinders; and dissolving the dissolvable layer with a solvent to expose the dots, disks or cylinders. The dots, disks or cylinders can be included with two sets of microelectrodes for ultrahigh speed rotation of miniature motors, and/or can be designed with a magnetic configuration into miniature motors for uniform rotation speeds and prescribed angular displacement.
    Type: Grant
    Filed: September 9, 2015
    Date of Patent: March 9, 2021
    Assignee: BOARD OF REGENTS, THE UNIVERSITY OF TEXAS SYSTEM
    Inventors: Donglei Fan, Kwanoh Kim, Jianhe Guo
  • Patent number: 10783947
    Abstract: According to one embodiment, a magnetic memory device includes a first member, a first memory cell, and a controller. The first member includes first, second, and third regions. The first memory cell includes first and second magnetic layers, and a first nonmagnetic layer. The second magnetic layer is provided between the third region and the first magnetic layer. The first nonmagnetic layer is provided between the first and second magnetic layers. The controller is electrically connected to the first and second regions, and the first magnetic layer. The controller programs first information to the first memory cell by setting the first magnetic layer to a first electric potential. The controller programs second information to the first memory cell by setting the first magnetic layer to a second electric potential. The second electric potential is different from the first electric potential. The second information is different from the first information.
    Type: Grant
    Filed: August 31, 2018
    Date of Patent: September 22, 2020
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsuhiko Koui, Hiroaki Yoda, Tomoaki Inokuchi, Naoharu Shimomura
  • Patent number: 10658574
    Abstract: A synthetic antiferromagnetic layer includes a first ferromagnetic layer containing an amorphizing element, the first ferromagnetic layer having a first structural symmetry; a second ferromagnetic layer having a second structural symmetry; wherein the first and the second ferromagnetic layers are antiferromagnetically coupled by a trifunctional non-magnetic multi-layered structure, the antiferromagnetic coupling being an Ruderman-Kittel-Kasuya-Yosida (RKKY) coupling, the non-magnetic multi-layered structure including at least two non-magnetic layers, the non-magnetic multilayered structure being at least partially nano-crystalline or amorphous in order to ensure a structural transition between the first ferromagnetic layer having the first structural symmetry and the second ferromagnetic layer having the second structural symmetry, the non-magnetic multilayered structure being adapted to absorb at least part of the amorphizing element out of the first ferromagnetic layer in contact with the non-magnetic multi
    Type: Grant
    Filed: August 10, 2018
    Date of Patent: May 19, 2020
    Assignees: COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES, CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE (CNRS), UNIVERSITE GRENOBLE ALPES
    Inventors: Jyotirmoy Chatterjee, Bernard Dieny, Ricardo Sousa, Stéphane Auffret
  • Patent number: 10276192
    Abstract: A magnetic recording medium includes an amorphous buffer layer, a hybrid layer including a barrier layer, and a texture control layer. The magnetic recording medium also includes a heat sink layer, an under layer, and a perpendicular recording layer.
    Type: Grant
    Filed: July 11, 2013
    Date of Patent: April 30, 2019
    Assignee: Western Digital Technologies, Inc.
    Inventors: Akemi Hirotsune, Ikuko Takekuma, Junichi Sayama
  • Patent number: 9991313
    Abstract: According to one embodiment, a magnetic memory includes a first magnetic layer, a second magnetic layer, a non-magnetic intermediate layer provided between the first magnetic layer and the second magnetic layer and an underlying layer provided on an opposite side of the first magnetic layer with respect to the intermediate layer, and the underlying layer contains AlN of a hcp structure.
    Type: Grant
    Filed: March 12, 2015
    Date of Patent: June 5, 2018
    Assignees: TOSHIBA MEMORY CORPORATION, SK HYNIX, INC.
    Inventors: Daisuke Watanabe, Makoto Nagamine, Youngmin Eeh, Koji Ueda, Toshihiko Nagase, Kazuya Sawada, Yang Kon Kim, Bo Mi Lee, Guk Cheon Kim, Won Joon Choi, Ki Seon Park
  • Patent number: 9984709
    Abstract: An apparatus is disclosed. The apparatus includes a storage layer, a thermal exchange control layer disposed over the storage layer, and a write layer disposed over the thermal exchange control layer. A Curie temperature of the thermal exchange control layer is lower than a Curie temperature of the storage layer. The Curie temperature of the thermal exchange control layer is lower than a Curie temperature of the write layer.
    Type: Grant
    Filed: March 22, 2017
    Date of Patent: May 29, 2018
    Assignee: Seagate Technology LLC
    Inventors: Pin-Wei Huang, YinFeng Ding, YingGuo Peng, Xiaobin Zhu, Kai-Chieh Chang, Yukiko Kubota, Timothy J. Klemmer, QiHong Wu, Ganping Ju, Jan-Ulrich Thiele, Florin Zavaliche
  • Patent number: 9799363
    Abstract: A magnetic stack includes a substrate and a magnetic recording layer disposed over the substrate. The magnetic recording layer comprises magnetic crystalline grains and a segregant disposed between grain boundaries of the crystalline grains. One or both of the magnetic crystalline grains and the segregant are doped with a rare earth or transition metal dopant in an amount that provides the magnetic recording layer with a magnetic damping value, ?, between about 0.1 to about 1.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: October 24, 2017
    Assignee: SEAGATE TECHNOLOGY, LLC
    Inventors: Xi Chen, Yingguo Peng, Jan-Ulrich Thiele, Ganping Ju, Thomas Roscamp
  • Patent number: 9679624
    Abstract: A magnetic random access memory (MRAM) cell including a magnetic tunnel junction containing: a storage layer including at least one storage ferromagnetic layer, each storage ferromagnetic layer having a storage magnetization; an antiferromagnetic storage layer pinning the storage magnetization at a low threshold temperature and freeing them at a high temperature threshold; a reference layer; and a tunnel barrier layer between the reference layer and the storage layer. The magnetic tunnel junction also includes a free ferromagnetic layer having a free magnetization adapted to induce a magnetic stray field magnetically coupling the free ferromagnetic layer with the storage layer; such that the storage magnetization can be switched by the magnetic stray field when the magnetic tunnel junction is at the high temperature threshold. The disclosed MRAM cell has low power consumption.
    Type: Grant
    Filed: November 19, 2013
    Date of Patent: June 13, 2017
    Assignee: CROCUS TECHNOLOGY SA
    Inventors: Lucien Lombard, Ioan Lucian Prejbeanu
  • Patent number: 9640752
    Abstract: According to one embodiment, a magnetoresistive element includes a recording layer having magnetic anisotropy perpendicular to a film surface and having a variable magnetization direction, a reference layer having magnetic anisotropy perpendicular to a film surface and having an invariable magnetization direction, an intermediate layer provided between the recording layer and the reference layer, and a underlayer containing AlTiN and provided on an opposite side of a surface of the recording layer on which the intermediate layer is provided.
    Type: Grant
    Filed: September 21, 2015
    Date of Patent: May 2, 2017
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Eiji Kitagawa, Tadashi Kai, Hiroaki Yoda
  • Patent number: 9431045
    Abstract: A magnetic media is described including a substrate, an unbalanced soft under layer (SUL), a magnetic seed layer, which may consist of one or more of NiWxCoy, NiWxCoyAlz, NiVaCob, NiVaCobAlc, NiWxVaCob, and NiWxVaFeb, and a magnetic recording layer.
    Type: Grant
    Filed: April 24, 2015
    Date of Patent: August 30, 2016
    Assignee: WD MEDIA, LLC
    Inventors: Zhenguo Wang, Iwao Okamoto, Sy Vu, Daehoon Hong
  • Patent number: 9373348
    Abstract: An apparatus that includes a storage layer and a heating assistance element. The heating assistance element is adjacent to the storage layer or doped into the storage layer. The heating assistance element is configured to enhance spatial confinement of energy from a field to an area of the storage layer to which the field is applied.
    Type: Grant
    Filed: November 22, 2013
    Date of Patent: June 21, 2016
    Assignee: Seagate Technology LLC
    Inventors: Michael Seigler, Weibin Chen, Werner Scholz, Jan Ulrich Thiele, Lihong Zhang, Xiong Liu, Shashwat Shukla
  • Patent number: 9349402
    Abstract: Provided herein is an apparatus comprising a substrate; a continuous layer over the substrate comprising a first heat sink layer; and a plurality of features over the continuous layer comprising a second heat sink layer, a first magnetic layer over the second heat sink layer, and a second magnetic layer, wherein the first and second magnetic layers are configured to provide a temperature-dependent, exchange spring mechanism.
    Type: Grant
    Filed: February 10, 2015
    Date of Patent: May 24, 2016
    Assignee: Seagate Technology LLC
    Inventors: Xi Chen, Ganping Ju, Yingguo Peng, Timothy J. Klemmer, Yukiko Kubota, Jan-Ulrich Thiele, David S. Kuo, Kai-Chieh Chang, Kangkang Wang, Li Gao, Yinfeng Ding
  • Patent number: 9245549
    Abstract: In one embodiment, magnetic read head includes a seed layer including an amorphous alloy film and Ru film positioned thereon, and an antiferromagnetic (AFM) layer positioned above the seed layer, the AFM layer including an alloy of MnIr having an L12 ordered phase, the amorphous alloy including a Co—X alloy having more Co than any other element, with X including at least one of: Zr, Nb, Ta, Hf, W, Si, and Al. In another embodiment, a method for forming a magnetic read head includes forming a seed layer above a substrate, heating at least the substrate to a first temperature in a range from about 150° C. to about 300° C., cooling at least the substrate to a second temperature of less than about 100° C., and forming an AFM layer above the seed layer between the heating and the cooling, the AFM layer comprising a MnIr alloy.
    Type: Grant
    Filed: May 13, 2013
    Date of Patent: January 26, 2016
    Assignee: HGST Netherlands B.V.
    Inventors: Kouichi Nishioka, Koujiro Komagaki
  • Patent number: 9199876
    Abstract: A thin lithium-aluminosilicate glass is provided. The glass is suitable for three dimensional precision molding and suitable for toughening, wherein after toughening, the glass has a center tension smaller than 50 Mpa, a surface compressive stress of 600-1200 Mpa, and a bending strength of up to 500 MPa. The glass also has a transition point lower than 550° C.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: December 1, 2015
    Assignee: SCHOTT GLASS TECHNOLOGIES (SUZHOU) CO., LTD.
    Inventors: Chong Wang, José Zimmer, Feng He, Gerhard Lautenschlaeger, Armin Vogl
  • Patent number: 9123359
    Abstract: A magnetic recording transducer for use in a data storage device is described. The transducer has a main writer pole and magnetic shields adjacent to the main writer pole. The magnetic shields include a first plated soft ferromagnetic layer, a second plated soft ferromagnetic layer, and an antiferromagnetic coupling (AFC) trilayer between the first plated soft ferromagnetic layer and the second plated soft ferromagnetic layer. The AFC trilayer includes a first AFC layer of sputtered ferromagnetic material; a second AFC layer of a nonmagnetic antiferromagnetic exchange material, and a third AFC layer of sputtered ferromagnetic material. Shields with AFC trilayers in leading, side, and/or trailing shields, as well as between shields are provided. A method of fabricating is also provided.
    Type: Grant
    Filed: December 22, 2010
    Date of Patent: September 1, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventors: Dehua Han, Ming Sun, Feng Liu, Jinqiu Zhang, Shaoping Li, Lieping Zhong, Xiaoqi Liu, Tao Pan
  • Patent number: 9093099
    Abstract: Provided are a perpendicular magnetic recording medium and a method for manufacturing the same, the perpendicular magnetic recording medium including an alloy (FePt, FePd, or CoPt) having a large Ku value with an L10 type ordered structure, and obtained with achievement of controlled crystal orientation and thin film formation without heating. Specifically, in the perpendicular magnetic recording medium, at least a nonmagnetic seed layer, a nonmagnetic underlayer, and a magnetic layer are formed in this order on a nonmagnetic substrate. The nonmagnetic seed layer includes a MgO layer and a metal layer having a body-centered cubic (bcc) structure. The nonmagnetic underlayer has a NaCl type structure of one selected from the group consisting of MgO, NiO, TiO, CrN, Ti carbides, and Ti nitrides. The magnetic layer includes an alloy selected from the group consisting of FePt, FePd, and CoPt having an L10 type ordered structure.
    Type: Grant
    Filed: July 8, 2013
    Date of Patent: July 28, 2015
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Yuki Inaba, Takehito Shimatsu
  • Patent number: 9053732
    Abstract: A method of forming a perpendicular magnetic recording medium. The perpendicular magnetic recording medium comprises a substrate, an underlayer on the substrate, an intermediate layer on the underlayer and a recording layer on the intermediate layer. The underlayer comprises a first soft underlayer, an antiferromagnetically coupled Ru layer on the first soft underlayer, a second soft underlayer on the antiferromagnetically coupled Ru layer, and an orientation control layer on the second soft underlayer, the method comprises applying a negative bias voltage to the substrate during formation of the underlayer.
    Type: Grant
    Filed: January 6, 2012
    Date of Patent: June 9, 2015
    Assignee: Showa Denko HD Singapore Pte Ltd.
    Inventors: Amarendra Kumar Singh, Shun Matsumoto, Xiao Dong Chen, Hiroshi Kanazawa
  • Patent number: 9040180
    Abstract: A perpendicular magnetic recording disk has a graded-anisotropy recording layer (RL) formed of at least two ferromagnetically exchange coupled CoPtCr-oxide magnetic layers (MAG1 and MAG2) with two nucleation films (NF1 and NF2) between the magnetic layers. NF1 is a metal film, preferably Ru or a Ru-based alloy like RuCr, sputter deposited on MAG1 at low pressure to a thickness between about 0.1-1.5 nm. NF2 is a metal oxide film, preferably an oxide of Ta, sputter deposited on NF1 at high pressure to a thickness between about 0.2-1.0 nm. MAG2 is sputter deposited over NF2. NF1 and NF2 provide a significant reduction in average grain size in the RL from a graded-anisotropy RL without nucleation films between MAG1 and MAG2, while also assuring that MAG1 and MAG2 are strongly exchange coupled.
    Type: Grant
    Filed: June 8, 2011
    Date of Patent: May 26, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: Ernesto E. Marinero, Dieter K. Weller, Brian R. York
  • Publication number: 20150103440
    Abstract: According to one embodiment, a perpendicular magnetic recording medium includes an underlayer in which the width of the grain boundary between crystal grains is less than 0.5 nm, and a multilayered magnetic recording layer formed in contact with the underlayer by alternately stacking at least two magnetic layers and two nonmagnetic layers, which are sequentially provided on a substrate. Each of the magnetic layers is a magnetically continuous layer. The magnetic layer includes magnetic crystal grains mainly containing Co, and a plurality of pinning sites made of an oxide dispersed in the entire magnetic layer. The perpendicular magnetic recording medium has a magnetic characteristic having a magnetization curve with a slope ? of 5 or more near the coercive force.
    Type: Application
    Filed: September 29, 2014
    Publication date: April 16, 2015
    Applicant: Kabushiki Kaisha Toshiba
    Inventor: Soichi OIKAWA
  • Publication number: 20150062745
    Abstract: In one embodiment, a magnetic storage device includes at least one microwave assisted magnetic recording (MAMR) head, each MAMR head including a spin torque oscillator (STO), a magnetic recording medium, a drive mechanism for passing the magnetic medium over the at least one MAMR head, and a controller electrically coupled to the at least one MAMR head for controlling operation of the at least one MAMR head, wherein the magnetic recording medium includes a recording layer positioned directly or indirectly above a substrate and an assist layer positioned above the recording layer, wherein the recording layer includes at least Co, Pt, and an oxide or oxygen, wherein the assist layer is positioned closer to the at least one MAMR head and includes at least Co and Pt, and wherein at least a portion of the recording layer has a smaller anisotropic magnetic field than the assist layer.
    Type: Application
    Filed: August 30, 2013
    Publication date: March 5, 2015
    Applicant: HGST Netherlands B.V.
    Inventors: Tatsuya Hinoue, Ichiro Tamai, Hiroaki Nemoto
  • Patent number: 8962164
    Abstract: A perpendicular magnetic recording medium adapted for high recording density and high data recording rate comprises a non-magnetic substrate having at least one surface with a layer stack formed thereon, the layer stack including a perpendicular recording layer containing a plurality of columnar-shaped magnetic grains extending perpendicularly to the substrate surface for a length, with a first end distal the surface and a second end proximal the surface, wherein each of the magnetic grains has: (1) a gradient of perpendicular magnetic anisotropy field Hk extending along its length between the first end and second ends; and (2) predetermined local exchange coupling strengths along the length.
    Type: Grant
    Filed: August 6, 2013
    Date of Patent: February 24, 2015
    Assignee: Seagate Technology LLC
    Inventors: Shaoping Li, Kaizhong Gao, Lei Wang, Wenzhong Zhu, Xiaobin Wang
  • Patent number: 8945732
    Abstract: A recording medium comprising a magnetic recording layer having an axis of magnetic anisotropy substantially perpendicular to the surface thereof, a soft magnetic underlayer disposed under the magnetic recording layer and physically coupled to the magnetic recording layer through one or more intermediate layers magnetically decoupling the soft magnetic underlayer from the magnetic recording layer, and an orientation initialization layer disposed between the magnetic recording layer and the soft magnetic underlayer.
    Type: Grant
    Filed: August 5, 2010
    Date of Patent: February 3, 2015
    Assignee: WD Media, LLC
    Inventors: Hua Yuan, Alexander Chernyshov, B. Ramamurthy Acharya
  • Publication number: 20150016236
    Abstract: Provided is a magnetic recording medium including a structure in which at least a soft magnetic underlayer, a non-magnetic intermediate layer, and a magnetic recording layer are sequentially laminated on a non-magnetic substrate, wherein the magnetic recording layer includes a first magnetic layer, a non-magnetic layer, and a second magnetic layer in order from the non-magnetic substrate side, has a structure in which the first magnetic layer and the second magnetic layer are magnetically separated from each other with the non-magnetic layer interposed therebetween, and consists of a plurality of patterns which are magnetically separated from each other, and the coercive force Hc of the second magnetic layer is larger than that of the first magnetic layer, and the coercive force Hc of the second magnetic layer is smaller than that of the first magnetic layer temporarily when the second magnetic layer is heated.
    Type: Application
    Filed: July 2, 2014
    Publication date: January 15, 2015
    Applicant: SHOWA DENKO K.K.
    Inventors: Akira SAKAWAKI, Akira YAMANE
  • Publication number: 20140356649
    Abstract: A ferromagnetically coupled magnetic recording medium having a first ferromagnetic layer, a second ferromagnetic layer, and a ferromagnetic coupling layer to ferromagnetically couple the first ferromagnetic layer to the second ferromagnetic layer is used as stable magnetic media with high MrT in high density recording hard drives. The first ferromagnetic layer is the stabilization layer and the second ferromagnetic layer is the main recording layer. The ferromagnetic coupling layer comprises a conductive material having a thickness which produces ferromagnetic coupling between said first ferromagnetic layer and said second ferromagnetic layer via the RKKY interaction.
    Type: Application
    Filed: August 18, 2014
    Publication date: December 4, 2014
    Inventors: Erol Girt, Mariana Rodica Munteanu, Hans Jurgen Richter, Felix Trejo
  • Patent number: 8902545
    Abstract: A magnetic recording medium may have a stacked structure including a first soft magnetic layer, an orientation control layer, a lower recording layer, an intermediate layer, and an upper recording layer that are sequentially stacked, and a second soft magnetic layer provided between the lower recording layer and the intermediate layer.
    Type: Grant
    Filed: June 18, 2013
    Date of Patent: December 2, 2014
    Assignee: Showa Denko K.K.
    Inventors: Hideaki Takahoshi, Daisuke Amiya, Hiroshi Sakai
  • Patent number: 8895163
    Abstract: In a perpendicular magnetic recording medium having, over a substrate, a magnetic recording layer, an underlayer made of Ru or a Ru compound and provided below the magnetic recording layer, a pre-underlayer made of a nonmagnetic crystalline material, and a soft magnetic layer provided below the pre-underlayer, when the difference between the highest point and the lowest point of unevenness of the interface between the soft magnetic layer and the pre-underlayer, derived by a cross-sectional TEM image, is given as an interface roughness (nm) and the distance between the soft magnetic layer and the magnetic recording layer, excluding the soft magnetic layer and the magnetic recording layer, is given as a SUL-MAG distance (nm), interface roughness (nm)?0.4 (nm) and interface roughness×SUL-MAG distance (nm)?12 (nm) are satisfied.
    Type: Grant
    Filed: March 31, 2010
    Date of Patent: November 25, 2014
    Assignee: WD Media (Singapore) Pte. Ltd.
    Inventor: Takahiro Onoue
  • Patent number: 8883249
    Abstract: By improving sliding durability while ensuring a high SNR, an improvement in reliability and a further increase in recording density are to be achieved.
    Type: Grant
    Filed: December 28, 2010
    Date of Patent: November 11, 2014
    Assignee: WD Media (Singapore) Pte. Ltd.
    Inventors: Toshiaki Tachibana, Takahiro Onoue, Keiichi Kajita
  • Patent number: 8871367
    Abstract: A perpendicular magnetic recording medium includes at least a soft-magnetic underlayer, a non-magnetic underlayer, a ferromagnetic intermediate layer, a non-magnetic intermediate layer, and a perpendicular magnetic recording layer sequentially stacked on a non-magnetic substrate. In an embodiment, the ferromagnetic intermediate layer is formed of a CoCr based alloy, a product Bs·t of a saturation magnetic flux density and film thickness of the ferromagnetic intermediate layer is within a range of 0.15 to 3.6 T·nm, and the non-magnetic intermediate layer has a film thickness of 3 nm or more.
    Type: Grant
    Filed: March 10, 2011
    Date of Patent: October 28, 2014
    Assignee: Fuji Electric Co., Ltd.
    Inventor: Hisato Kato
  • Publication number: 20140313615
    Abstract: Provided herein is an apparatus, including a magnetically soft underlayer (SUL); an interlayer stack overlying the SUL, wherein the interlayer stack comprises a seed layer of an fcc material; and a perpendicular magnetic recording layer overlying the interlayer stack, wherein a thickness of the SUL in combination with a distance of the SUL from the perpendicular recording layer is sufficient to orient a total magnetic field corresponding to a magnetic transducer head at an angle of about 45°.
    Type: Application
    Filed: March 28, 2014
    Publication date: October 23, 2014
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Thomas P. Nolan, Li Tang, Yong-Chang Feng, Zhong (Stella) Wu, Samuel D. Harkness, Hans J. Richter, Youfeng Zheng
  • Patent number: 8852677
    Abstract: A method for fabricating a synthetic antiferromagnetic device, includes depositing a magnesium oxide spacer layer on a reference layer having a first and second ruthenium layer, depositing a cobalt iron boron layer on the magnesium oxide spacer layer; and depositing a third ruthenium layer on the cobalt iron boron layer, the third ruthenium layer having a thickness of approximately 0-18 angstroms.
    Type: Grant
    Filed: August 3, 2012
    Date of Patent: October 7, 2014
    Assignee: International Business Machines Corporation
    Inventors: David W. Abraham, Michael C. Gaidis, Janusz J. Nowak, Daniel C. Worledge
  • Patent number: 8852762
    Abstract: A synthetic antiferromagnetic device includes a reference layer having a first and second ruthenium layer, a magnesium oxide spacer layer disposed on the reference layer, a cobalt iron boron layer disposed on the magnesium oxide spacer layer and a third ruthenium layer disposed on the cobalt iron boron layer, the third ruthenium layer having a thickness of approximately 0 angstroms to 18 angstroms.
    Type: Grant
    Filed: July 31, 2012
    Date of Patent: October 7, 2014
    Assignee: International Business Machines Corporation
    Inventors: David W. Abraham, Michael C. Gaidis, Janusz J. Nowak, Daniel C. Worledge
  • Publication number: 20140234665
    Abstract: A perpendicular magnetic recording disk includes a template layer below a Ru or Ru alloy underlayer, with a granular Co alloy recording layer formed on the underlayer. substrate. The template layer comprises nanoparticles spaced-apart and partially embedded within a polymer material, with the nanoparticles protruding above the surface of the polymer material. A seed layer covers the surface of the polymer material and the protruding nanoparticles and an underlayer of Ru or a Ru alloy covers the seed layer. The protruding nanoparticles serve as the controlled nucleation sites for the Ru or Ru alloy atoms. The nanoparticle-to-nanoparticle distances can be controlled during the formation of the template layer. This enables control of the Co alloy grain diameter distribution as well as grain-to-grain distance distribution.
    Type: Application
    Filed: February 20, 2013
    Publication date: August 21, 2014
    Applicant: HGST NETHERLANDS B.V.
    Inventors: Bruce Alvin Gurney, Ricardo Ruiz, Manfred Ernst Schabes, Kentaro Takano, Shi-Ling Chang Wang, Qing Zhu, Han Zou
  • Patent number: 8795478
    Abstract: Embodiments of the invention provide a manufacturing method which permits a high quality perpendicular magnetic recording medium to be manufactured with a high yield by preventing abnormal discharge which sputters particles from the target. In one embodiment, while the perpendicular magnetic recording medium is formed, DC pulses are applied to the target. During the reversal period (Reversal Time) between sputtering periods, a voltage of the opposite polarity is applied. During the sputtering period, a negative voltage is applied which biases the target surface to a negative potential, causing Ar+ to collide with and sputter CoCrPt and SiO2 for deposition on the intermediate layer. The top surface of the insulation material (SiO2) on the target is charged by Ar+ to have a voltage larger than the target voltage. However, arcing can be prevented since the charge on the surface of the insulation material is neutralized due to a positive voltage applied to the target during the non-sputtering period.
    Type: Grant
    Filed: October 18, 2005
    Date of Patent: August 5, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Yoshinori Honda, Takayuki Ichihara, Hiroyuki Nakagawa, Kiwamu Tanahashi
  • Patent number: 8787130
    Abstract: Systems and methods for providing heat assisted magnetic recording (HAMR) media configured to couple energy from a near field transducer (NFT) are provided. One such method includes providing a magnetic recording layer including an L10 ordered FePt or an L10 ordered CoPt, selecting a plurality of preselected parameters for a coupling layer, the preselected parameters including a material, a preselected deposition temperature, and a preselected thickness, and depositing the coupling layer directly on the magnetic recording layer using the preselected parameters such that the coupling layer has an extinction coefficient greater than 0.1.
    Type: Grant
    Filed: June 29, 2013
    Date of Patent: July 22, 2014
    Assignee: WD Media, LLC
    Inventors: Hua Yuan, Bogdan F. Valcu, Antony Ajan, B. Ramamurthy Acharya, Alexander S. Chernyshov, Paul C. Dorsey
  • Patent number: 8747628
    Abstract: A method according to one embodiment includes forming a high Ku first oxide magnetic layer above a substrate by sputtering; forming a low Ku second oxide magnetic layer above the first oxide magnetic layer by sputtering; forming an exchange coupling layer of CoCrPt-oxide above the second oxide magnetic layer; and forming a magnetic cap layer above the exchange coupling layer. Additional systems and methods are also presented.
    Type: Grant
    Filed: April 3, 2012
    Date of Patent: June 10, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Xiaoping Bian, Jack Jyh-Kau Chang, Qing Dai, Hoa V. Do, Yoshihiro Ikeda, Kentaro Takano, Chu S. Tran
  • Publication number: 20140145792
    Abstract: Synthetic antiferromagnetic (SAF) and synthetic ferrimagnetic (SyF) free layer structures are disclosed that reduce Ho (for a SAF free layer), increase perpendicular magnetic anisotropy (PMA), and provide higher thermal stability up to at least 400° C. The SAF and SyF structures have a FL1/DL1/spacer/DL2/FL2 configuration wherein FL1 and FL2 are free layers with PMA, the coupling layer induces antiferromagnetic or ferrimagnetic coupling between FL1 and FL2 depending on thickness, and DL1 and DL2 are dusting layers that enhance the coupling between FL1 and FL2. The SAF free layer may be used with a SAF reference layer in STT-MRAM memory elements or in spintronic devices including a spin transfer oscillator. Furthermore, a dual SAF structure is described that may provide further advantages in terms of Ho, PMA, and thermal stability.
    Type: Application
    Filed: November 27, 2012
    Publication date: May 29, 2014
    Applicant: HEADWAY TECHNOLOGIES, INC.
    Inventors: Yu-Jen Wang, Guenole Jan, Ru-Ying Tong
  • Publication number: 20140139951
    Abstract: According to one embodiment, a perpendicular magnetic recording medium includes a nonmagnetic interlayer formed on a nonmagnetic substrate, an antiferromagnetic layer having a thickness of 2 to 30 nm, a first nonmagnetic underlayer having a thickness of 0.2 to 5 nm, a first bit patterned ferromagnetic layer, a first bit patterned nonmagnetic layer, and a second bit patterned ferromagnetic layer.
    Type: Application
    Filed: January 24, 2014
    Publication date: May 22, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tomoyuki Maeda, Yousuke Isowaki, Akira Watanabe, Akihiko Takeo
  • Publication number: 20140093747
    Abstract: A magnetic recording medium includes a substrate and a plurality of anisotropic magnetic layers applied over the substrate. The medium further includes at least one anti-ferromagnetic coupling layer between two adjacent anisotropic magnetic layers of the plurality of anisotropic magnetic layers.
    Type: Application
    Filed: September 28, 2012
    Publication date: April 3, 2014
    Applicant: HGST NETHERLANDS B.V.
    Inventor: Ernesto E. Marinero
  • Publication number: 20140093746
    Abstract: An apparatus includes a disk substrate and a soft underlayer overlying the disk substrate. A magnetic seed layer overlies the soft underlayer, wherein the magnetic seed layer is formed by a hexagonal close-packed lattice material and has in-plane magnetic anisotropy.
    Type: Application
    Filed: September 30, 2012
    Publication date: April 3, 2014
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Antonio Javier Zambano, Li Tang, John David Westwood
  • Publication number: 20140063656
    Abstract: Provided is a magnetic recording medium which maintains high vertical orientation of a vertical magnetic layer, and which is capable of realizing high recording densification. In the magnetic recording medium, at least a soft magnetic underlying layer (30), seed layers (31, 32), an orientation control layer (33), and a vertical magnetic layer are laminated in this order on the non-magnetic substrate. The soft magnetic underlying layer (30) has an amorphous or microcrystalline structure. The seed layers (31, 32) include a first seed layer (31) formed from a metal oxide or a metal nitride, and a second seed layer (32) which is formed on the first seed layer and is formed from a metal formed with an island-shape or a net shape. In the orientation control layer (33) and the vertical magnetic layer, respective crystal grains constitute columnar crystals that are continuous in a thickness direction based on the second seed layer (32).
    Type: Application
    Filed: May 14, 2012
    Publication date: March 6, 2014
    Applicant: SHOWA DENKO K.K.
    Inventor: Atsushi Hashimoto
  • Patent number: 8658292
    Abstract: Systems and methods for controlling the damping of magnetic media for magnetic recording are described. One such system includes a magnetic media structure for magnetic recording, the media structure including at least one base layer including an interlayer, a bottom magnetic recording layer positioned on the interlayer, and an exchange coupling layer positioned on the bottom layer; and a capping magnetic recording layer positioned on the at least one base layer, the capping recording layer including a first material configured to increase a damping constant of the capping recording layer to a first preselected level.
    Type: Grant
    Filed: June 10, 2011
    Date of Patent: February 25, 2014
    Assignee: Western Digital Technologies, Inc.
    Inventors: Michael L. Mallary, Gerardo A. Bertero
  • Publication number: 20140044993
    Abstract: Apparatus for recording data and method for making the same. In accordance with some embodiments, a recording layer is supported by a substrate. The recording layer has a granular magnetic recording layer with a first oxide content, a continuous magnetic recording layer with nominally no oxide content, and an oxide gradient layer disposed between the respective granular magnetic recording layer and the continuous magnetic recording layer. The oxide gradient layer has a second oxide content less than the first oxide content of the granular layer.
    Type: Application
    Filed: October 16, 2013
    Publication date: February 13, 2014
    Applicant: Seagate Technology LLC
    Inventors: Pengcheng Li, Bin Lu, Thomas P. Nolan, Li-Lien Lee, Jai-Young Kim
  • Publication number: 20140030552
    Abstract: A perpendicular magnetic recording medium is disclosed. The perpendicular magnetic recording medium includes a first layer, and a second layer positioned immediately below the first layer. Among the materials in the first layer and the second layer, if the interface energy when two different materials—material a and material b—are in contact is defined as Ei(a//b), the surface energy when material a exists independently is defined as Es(a), and the energy resulting by subtracting the sum of the respective surface energies (?Es) from the interface energy is defined as G(a//b), then when G(1//3)<G(1//4) holds, either G(2//4) or G(1//3) is the minimum among G(1//3), G(1//4), G(2//3) and G(2//4), and when G(1//3)<G(1//4) does not hold, G(2//4) is the minimum among G(1//3), G(1//4), G(2//3) and G(2//4).
    Type: Application
    Filed: June 4, 2013
    Publication date: January 30, 2014
    Inventors: Yuki INABA, Takayuki HIROSE
  • Publication number: 20140011053
    Abstract: A perpendicular magnetic recording medium adapted for high recording density and high data recording rate comprises a non-magnetic substrate having at least one surface with a layer stack formed thereon, the layer stack including a perpendicular recording layer containing a plurality of columnar-shaped magnetic grains extending perpendicularly to the substrate surface for a length, with a first end distal the surface and a second end proximal the surface, wherein each of the magnetic grains has: (1) a gradient of perpendicular magnetic anisotropy field Hk extending along its length between the first end and second ends; and (2) predetermined local exchange coupling strengths along the length.
    Type: Application
    Filed: August 6, 2013
    Publication date: January 9, 2014
    Applicant: Seagate Technology LLC
    Inventors: Shaoping Li, Kaizhong Gao, Lei Wang, Wenzhong Zhu, Xiaobin Wang
  • Publication number: 20140002919
    Abstract: A magnetic recording medium may include a stacked structure of orientation control, lower recording, intermediate, and upper recording layers. The lower recording layer has a coercivity higher than that of the upper recording layer. The lower recording layer includes a first layer with a granular structure that includes magnetic particles including Co, Cr, and Pt, and an oxide covering a periphery of the magnetic particles, and a second layer with a non-granular structure that includes magnetic particles including Co, Cr, and Pt. The lower recording layer includes columnar crystals continuous with crystal particles forming the orientation control layer in a stacking direction of the stacked structure.
    Type: Application
    Filed: May 24, 2013
    Publication date: January 2, 2014
    Applicant: SHOWA DENKO K.K.
    Inventors: Hideaki TAKAHOSHI, Daisuke AMIYA, Hiroshi SAKAI
  • Publication number: 20130334631
    Abstract: Memory cells are disclosed. Magnetic regions within the memory cells include an alternating structure of magnetic sub-regions and coupler sub-regions. The coupler material of the coupler sub-regions antiferromagnetically couples neighboring magnetic sub-regions and effects or encourages a vertical magnetic orientation exhibited by the neighboring magnetic sub-regions. Neighboring magnetic sub-regions, spaced from one another by a coupler sub-region, exhibit oppositely-directed magnetic orientations. The magnetic and coupler sub-regions may each be of a thickness tailored to form the magnetic region in a compact structure. Interference between magnetic dipole fields emitted from the magnetic region on switching of a free region in the memory cell may be reduced or eliminated. Also disclosed are semiconductor device structures, spin torque transfer magnetic random access memory (STT-MRAM) systems, and methods of fabrication.
    Type: Application
    Filed: June 19, 2012
    Publication date: December 19, 2013
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: Wayne I. Kinney, Witold Kula, Stephen J. Kramer