Magnetic Recording Medium Or Device Formed Patents (Class 427/599)
  • Patent number: 8383209
    Abstract: [Problems] To have a thin film suitably function even when the thickness of the thin film is reduced. [Means for Solving Problems] Provided is a method for manufacturing a magnetic recording medium by forming a thin film on a substrate (12). The method is provided with a thin film forming step of forming the thin film by using a substance brought into the plasma state as a material. In the thin film forming step, the thin film is formed by using a material substance gathering means (30) for gathering the substance brought into the plasma state to the periphery of the substrate. The material substance gathering means (30) gathers the substance brought into the plasma state, for instance, to the periphery of the substrate (12) by generating a magnetic field at the periphery of the substrate (12).
    Type: Grant
    Filed: September 26, 2007
    Date of Patent: February 26, 2013
    Assignee: WD Media (Singapore) Pte. Ltd.
    Inventor: Kenji Ayama
  • Publication number: 20120280774
    Abstract: A magnetic shield for a magnetoresistive (MR) reader has one or more lateral hard magnets and a ferromagnetic shielding layer with at least one hard sub-magnet in a lateral notch in the shielding layer. The notch allows the shielding layer to contact the sub-magnet on surfaces along multiple normal planes.
    Type: Application
    Filed: May 6, 2011
    Publication date: November 8, 2012
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Eric W. Singleton, Junjie Quan, Jae-Young Yi
  • Patent number: 8263191
    Abstract: There is described a method of producing color effect images on a carrier substrate, wherein it is provided that a latent magnetic image comprising magnetic pixels and non-magnetic pixels is produced on a magnetizable printing form, a carrier substrate with a decorative layer applied to the carrier substrate and provided with non-spherical, preferably needle-form or flake-form magnetic color effect pigments is moved past the magnetizable printing form so that color effect pigments of the decorative layer are changed in their orientation relative to the carrier substrate by the field line image produced by the magnetic pixels of the magnetizable printing form, and the color effect pigments are fixed in the decorative layer in the orientation which is changed by the field line image of the printing form. There is further described an apparatus for carrying out the method and a multi-layer body produced therewith.
    Type: Grant
    Filed: April 26, 2006
    Date of Patent: September 11, 2012
    Assignee: Leonhard Kurz Stiftung & Co. KG
    Inventor: Heinrich Wild
  • Patent number: 8252367
    Abstract: Soft magnetic film fabricated with preferred uniaxial anisotropy for perpendicular recording. One type of cathode design has a field direction that is parallel to the direction of the Hex of the second SUL with a magnetically-pinned first SUL. In addition, SUL structures having low AP exchange energy also are disclosed. The SUL structure combines the cathode field direction of the SUL2 with the pinned SUL1. The SUL1 is magnetically pinned to the pinning layer and the pinning direction is parallel to the direction of the cathode field applied during deposition of the SUL1. High Hc ferro-magnetic materials may be deposited onto a heated substrate that is magnetized along the radial direction by the cathode field. The pinning field may be higher than the cathode field, indicating that the cathode field during deposition of the SUL2 cannot disturb the magnetic state of the SUL1 pinned to pinning layer.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: August 28, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Gunn Choe, Yoshihiro Ikeda, Masayoshi Shimizu, Kiwamu Tanahashi
  • Publication number: 20120112741
    Abstract: To provide a method which can define the direction and orientation of magnetization of a pinned layer while reducing the number of steps of forming a GMR film. The magnetization direction of the pinned layer is defined in a plurality of directions by forming a plurality of patterns having directivities. Further, when the magneto-resistive effect film is formed, a magnetic field is applied in a direction at an angle set between the angles of the plurality of patterns.
    Type: Application
    Filed: July 13, 2010
    Publication date: May 10, 2012
    Applicant: HITACHI METALS, LTD.
    Inventors: Kenichi Meguro, Hiroyuki Hoshiya, Keizou Katou, Yasunori Abe
  • Publication number: 20110151144
    Abstract: Embodiments of the invention provide a perpendicular magnetic recording medium improved for fly ability, high in read signal quality, and capable of suppressing magnetic decay of recorded magnetization to be caused by stray fields. In one embodiment, a perpendicular recording layer is formed over a substrate with a soft magnetic underlayer therebetween, then an amorphous or nano-crystalline layer is formed between the substrate and the soft magnetic underlayer. The soft magnetic underlayer includes first and second amorphous soft magnetic layers, as well as a nonmagnetic layer formed between those first and second amorphous soft magnetic layers. The first and second amorphous soft magnetic layers are given uniaxial anisotropy in the radial direction of the substrate respectively and coupled with each other antiferromagnetically.
    Type: Application
    Filed: December 15, 2010
    Publication date: June 23, 2011
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Reiko Arai, Kiwamu Tanahashi, Yoshinori Honda, Mineaki Kodama
  • Patent number: 7842334
    Abstract: A magnetic sensor includes a single substrate, a conventional GMR element formed of a spin-valve film including a single-layer-pinned fixed magnetization layer, and a SAF element formed of a synthetic spin-valve film including a plural-layer-pinned fixed magnetization layer. When the spin-valve film intended to act as the conventional GMR element and the synthetic spin-valve film intended to act as the SAF element are subjected to the application of a magnetic field oriented in a single direction at a high temperature, they become giant magnetoresistive elements whose magnetic-field-detecting directions are antiparallel to each other. Since films intended to act as the conventional GMR element and the SAF element can be disposed close to each other, the magnetic sensor which has giant magnetoresistive elements whose magnetic-field-detecting directions are antiparallel to each other can be small.
    Type: Grant
    Filed: February 6, 2008
    Date of Patent: November 30, 2010
    Assignee: Yamaha Corporation
    Inventors: Yukio Wakui, Masayoshi Omura
  • Publication number: 20100297364
    Abstract: A servo pattern forming method of a hard disk drive includes magnetically printing a reference servo pattern, which has different features according to zones divided along a radial direction of a disk, on the disk, and recording a final servo pattern in the disk on the basis of the reference servo pattern. As a result, the quality of a final servo pattern can be enhanced by preventing an amplitude drop that arises in an ID zone of the disk when a reference servo pattern is recorded using a conventional servo track writer.
    Type: Application
    Filed: May 20, 2010
    Publication date: November 25, 2010
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Yoon Chul CHO, Cheol-Soon Kim, Ha Yong Kim
  • Publication number: 20100215988
    Abstract: A method is provided for the preparation of nanomaterials, which involves the dissolution and/or suspension of a combination of (a) one or more resin substrate materials and (b) one or more magnetic nanoparticutate substances, in a medium made from one or more ionic liquids, to provide a mixture, and recovering the solid nanomaterial by combining the mixture with a non-solvent (solvent for the ionic liquids but not the other components), while also applying an electromagnetic field to the mixture during the recovering step to align the magnetic nanoparticulate substances, along with the use of the resulting nanomaterials to provide unique information storage media, particularly in the form of sheets or films.
    Type: Application
    Filed: May 30, 2006
    Publication date: August 26, 2010
    Inventors: Dan Daly, Robin D. Rogers
  • Publication number: 20100102028
    Abstract: Disclosed is a method for manufacturing a template for a high-density patterned medium and a high-density magnetic storage medium using the same. In the method, magnetic particles are used as a mask and no lithographic process is required.
    Type: Application
    Filed: December 28, 2009
    Publication date: April 29, 2010
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Hae Sung KIM, Myung Bok Lee, Jin Seung Sohn
  • Patent number: 7553426
    Abstract: An apparatus, system, and method are disclosed for increasing data storage density in patterned media. One or more deposition sources may apply magnetic material to one or more recesses formed in a substrate, each recess having opposing sidewalls that are effectively coated by the deposition sources. The top surface of the substrate may subsequently be planarized to remove magnetic material from such surface, thereby isolating one or more recordable magnetic regions formed on each sidewall. In this manner, the present invention may provide at least two recordable regions for every recess formed in a substrate.
    Type: Grant
    Filed: March 1, 2005
    Date of Patent: June 30, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Thomas Robert Albrecht, Henry Hung Yang
  • Publication number: 20090162573
    Abstract: Soft magnetic film fabricated with preferred uniaxial anisotropy for perpendicular recording. One type of cathode design has a field direction that is parallel to the direction of the Hex of the second SUL with a magnetically-pinned first SUL. In addition, SUL structures having low AP exchange energy also are disclosed. The SUL structure combines the cathode field direction of the SUL2 with the pinned SUL1. The SUL1 is magnetically pinned to the pinning layer and the pinning direction is parallel to the direction of the cathode field applied during deposition of the SUL1. High Hc ferro-magnetic materials may be deposited onto a heated substrate that is magnetized along the radial direction by the cathode field. The pinning field may be higher than the cathode field, indicating that the cathode field during deposition of the SUL2 cannot disturb the magnetic state of the SUL1 pinned to pinning layer.
    Type: Application
    Filed: December 19, 2007
    Publication date: June 25, 2009
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS BV
    Inventors: Gunn Choe, Yoshihiro Ikeda, Masayoshi Shimizu, Kiwamu Tanahashi
  • Publication number: 20090097365
    Abstract: Provided are a magnetic layer, a method of forming the magnetic layer, an information storage device, and a method of manufacturing the information storage device. The information storage device may include a magnetic track having a plurality of magnetic domains, a current supply element connected to the magnetic layer and a reading/writing element. The magnetic track includes a hard magnetic track, and the hard magnetic track has a magnetization easy-axis extending in a direction parallel to a width of the hard magnetic track.
    Type: Application
    Filed: February 29, 2008
    Publication date: April 16, 2009
    Inventors: Sung-chul Lee, Sun-ae Seo, Young-Jin Cho, Kwang-seok Kim
  • Publication number: 20090087589
    Abstract: Simultaneous setting of exchange pinning field magnetization in more than one direction for several thin film structures on a single substrate has been achieved by first orienting the structures as needed. A layer of hard magnetic material is then deposited, suitably patterned to control the direction of its flux, and then magnetized through a single exposure to a strong magnetic field. The assemblage is then thermally annealed (in the absence of any applied field) at a temperature higher than the AFM material blocking temperature, following which the thin film structures are magnetically pinned in the intended directions.
    Type: Application
    Filed: September 28, 2007
    Publication date: April 2, 2009
    Inventors: Yimin Guo, Grace Gorman
  • Publication number: 20090047448
    Abstract: A soft magnetic thin film in which the recording magnetic field in the perpendicular direction can be preferentially intensified and sharply controlled when the thin film is applied to a perpendicular magnetic recording medium is provided. This soft magnetic thin film can be obtained by immersing a substrate into an electroless plating bath that contains a Co ion, Fe ion, and Ni ion as metal ions, as well as a completing agent and a boron-type reducing agent, wherein the content ratios of the metal ions on the mole basis are 0.15? (Ni ion amount/the amount of total metal ions) ?0.40, 0.50? (Co ion amount/the amount of total metal ions) ?0.80, and 0.05? (Fe ion amount/the amount of total metal ions) ?0.15; and carrying out electroless plating in a magnetic field in a range of 5-2,000 Oe given in a direction parallel to the surface of said substrate.
    Type: Application
    Filed: October 17, 2008
    Publication date: February 19, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Sanae Shimizu, Daiju Kaneko, Takuya Uzumaki, Atsushi Tanaka
  • Publication number: 20090029190
    Abstract: A process for producing a perpendicular magnetic recording medium comprises forming metallic nuclei or a seed layer on a non-magnetic substrate, and forming a soft magnetic under layer on the metallic nuclei or the seed layer by means of electroless plating. The soft magnetic under layer is formed while an external parallel magnetic field is applied to the non-magnetic substrate, and the substrate is rotated such that the substrate is maintained parallel to the parallel magnetic field.
    Type: Application
    Filed: September 29, 2008
    Publication date: January 29, 2009
    Applicants: Showa Denko K.K., Waseda University
    Inventors: Masahiro Ohmori, Hiroshi Ohta, Tetsuya Osaka, Toru Asahi, Tokihiko Yokoshima
  • Patent number: 7482041
    Abstract: A device having a substrate, a pair of ferromagnetic leads on a surface of the substrate, laterally separated by a gap, and one or more ferromagnetic microparticles comprising a conductive coating at least partially within the gap. The conductive coating forms at least part of an electrical connection between the leads. A molecular junction may connect the leads to the microparticle.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: January 27, 2009
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: David P Long, James G Kushmerick, Jr.
  • Publication number: 20090002875
    Abstract: A magnetic recording medium and a method of fabricating the same are provided. The magnetic recording medium in which a position for magnetic recording is patterned with a magnetic material, includes a magnetic recording layer which includes a data area having a plurality of data tracks, and a servo area having a servo burst for following the data tracks, wherein the servo burst includes a plurality of bursts disposed in a zigzag structure along a downtrack direction, and each of the bursts includes a plurality of burst pieces having different coercivities from each other. The magnetic recording medium is subjected to two servo-recording processes, so that a signal similar to an alternative signal written in a burst having a burst pattern used in a related art continuous medium can be obtained.
    Type: Application
    Filed: January 23, 2008
    Publication date: January 1, 2009
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Hoo-san Lee, Hoon-sang Oh, Sung-hoon Choa
  • Patent number: 7431961
    Abstract: In this invention, we replace low resistivity NiFe with high-resistivity FeNi for the FL2 portion of a composite free layer in a CIP GMR sensor in order to minimize current shunting effects while still retaining both magnetic softness and low magnetostriction. A process for manufacturing the device is also described.
    Type: Grant
    Filed: December 10, 2004
    Date of Patent: October 7, 2008
    Assignee: Headway Technologies, Inc.
    Inventors: Tong Zhao, Hui-Chuan Wang, Yun-Fei Li, Chyu-Jiuh Torng
  • Publication number: 20080176008
    Abstract: A magnetic film forming apparatus can form a magnetic film, especially a magnetic alloy film, selectively on a metal surface exposed on a surface of a substrate, such as a semiconductor wafer. The magnetic film forming apparatus comprises an electroless plating apparatus having a magnetic field generation apparatus for generating a magnetic field around and parallel to a substrate disposed such that the surface of the substrate is in contact with a plating solution in a plating tank.
    Type: Application
    Filed: January 22, 2008
    Publication date: July 24, 2008
    Inventors: Xinming Wang, Akira Owatari, Takashi Koba, Tsutomu Nakada, Akira Fukuda
  • Publication number: 20080152954
    Abstract: An information storage device includes a writing magnetic layer including a magnetic domain wall. An information storing magnetic layer is connected to the writing magnetic layer, and includes at least one magnetic domain wall. The information storage device also includes a reader for reading data recorded in the information storing magnetic layer. The connection layer includes a first portion with a first width adjacent to the writing magnetic layer and a second portion with a second width adjacent to the at least one information storing magnetic layer. The first width is less than the second width.
    Type: Application
    Filed: October 31, 2007
    Publication date: June 26, 2008
    Inventor: Chee-Kheng Lim
  • Publication number: 20080124581
    Abstract: A TMR element includes a lower magnetic layer, an upper magnetic layer, and a tunnel barrier layer of crystalline insulation material sandwiched between the lower magnetic layer and the upper magnetic layer. The lower magnetic layer includes a first magnetic layer and a second magnetic layer sandwiched between the first magnetic layer and the tunnel barrier layer. The second magnetic layer is formed from a magnetic material containing at least one of Fe, Co and Ni.
    Type: Application
    Filed: November 26, 2007
    Publication date: May 29, 2008
    Applicant: TDK CORPORATION
    Inventors: Satoshi MIURA, Takumi YANAGISAWA
  • Publication number: 20080118781
    Abstract: Perpendicular magnetic recording media enabling high-density recording and reproduction of information, as well as a production process thereof, and a magnetic recording and reproducing apparatus, are provided. Perpendicular magnetic recording media, having at least a soft magnetic underlayer and perpendicular magnetic recording layer on a disc-shaped nonmagnetic substrate, in which the soft magnetic underlayer has at least two soft magnetic layers, and Ru or Re between the two soft magnetic layers, are provided; the easy axis of magnetization of the soft magnetic underlayer has a desired direction; the easy axis of magnetization of the soft magnetic underlayer is substantially distributed in a direction except a radial direction of the nonmagnetic substrate, and, the bias magnetic field of the antiferromagnetic coupling in the direction of the easy axis of magnetization of the soft magnetic underlayer is 10 Oersteds (790 A/m) or greater.
    Type: Application
    Filed: January 31, 2006
    Publication date: May 22, 2008
    Applicants: Tohoku University, SHOWA DENKO K.K., Kabushiki Kaisha Toshiba
    Inventors: Migaku Takahashi, Masahiro Oka, Akira Kikitsu
  • Publication number: 20080003378
    Abstract: Producing magnetic-recording media includes providing a substrate and forming a plurality of functional layers over the substrate to provide a coated substrate adapted for recording. At least one of the layers of the magnetic-recording media is fluid jet printed as a printed layer. In some embodiments, the printed layer provides at least one of load-bearing functionality, head-cleaning functionality, adhesion-promoting functionality, reaction-promoting functionality, lubricating functionality, surface-cleansing functionality, magnetic-recording functionality, and edge-finishing functionality.
    Type: Application
    Filed: June 30, 2006
    Publication date: January 3, 2008
    Inventors: Mark Serafin, Stephen R. Ebner, David C. Lowery, Neal K. Nelson, Michael Steiner
  • Patent number: 7258900
    Abstract: A magnetic field is applied to planarize magnetic pigment flakes relative to a surface. Pigment flakes, such as optically variable pigment flakes, are used in a variety of paints, inks, extrusions, powder coatings, and other forms for decorative and security applications. In many applications pigment flakes tend to align parallel to each other and to the surface to which they are applied. If the pigment flakes include a suitable magnetic structure, a magnetic field can be applied to subsequently align the flakes or enhance the alignment of the flakes in the plane of the substrate if the carrier that the flakes are dispersed in is still fluid. In some printing operations, pigment flakes that are applied parallel to the substrate are pulled out of plane when the print screen or printing die is lifted off the substrate. Application of a magnetic field can re-align pigment flakes to the plane of the substrate, enhancing the visual quality of the printed image, especially with optically variable pigments.
    Type: Grant
    Filed: November 13, 2002
    Date of Patent: August 21, 2007
    Assignee: JDS Uniphase Corporation
    Inventors: Vladimir P. Raksha, Charles T. Markantes, Dishuan Chu, Paul G. Coombs
  • Patent number: 7252863
    Abstract: A rubbing method, i.e., a method of forming an alignment layer, of a liquid crystal display device includes providing a substrate, applying an alignment layer on the substrate, applying a magnetic field to the alignment layer by a magnetic field generator and firing the alignment layer.
    Type: Grant
    Filed: October 29, 2004
    Date of Patent: August 7, 2007
    Assignee: LG.Philips LCD Co., Ltd.
    Inventors: Jae-Choon Ryu, Hae-Joon Son
  • Patent number: 7208204
    Abstract: A method and apparatus for forming a thin film magnetic recording media, the method comprises generating magnetic nanoclusters from a target of magnetic material, crystallizing the magnetic nanoclusters, and depositing the magnetic nanoclusters onto a substrate to form a thin film of magnetic particles thereon. The magnetic nanoclusters are deposited onto the substrate after crystallized and therefore after the deposition. The apparatus comprises a first chamber, a second chamber connected to the first chamber, and a third chamber connected to the second chamber. The first chamber has a source for generating magnetic nanoclusters. The second chamber is to receive the magnetic nanoclusters and crystallize the magnetic nanocluster. The third chamber is to receive the crystallized magnetic nanoclusters from the second chamber and deposit the crystallized magnetic nanoclusters onto the substrate positioned therein.
    Type: Grant
    Filed: February 11, 2004
    Date of Patent: April 24, 2007
    Assignee: Agency for Science, Technology and Research
    Inventors: Jingsheng Chen, Jian-Ping Wang
  • Patent number: 7201947
    Abstract: As track widths of magnetic read heads grow very small, conventional longitudinal bias stabilization has been found to no longer be suitable since the strong magnetostatic coupling at the track edges also pins the magnetization of the free layer. This problem has been overcome by extending the free layer so that it is no longer confined to the area immediately below the spacer or tunneling layer. A longitudinal bias layer immediately below the free layer is given a relatively weak magnetic exchange coupling field of about 200 Oe. Although there is strong exchange coupling between this and the free layer, the degree of pinning of the free layer is low so that the device's output signal is reduced by less than about 10%. A process for manufacturing both the CPP SV and a MTJ versions of the invention is described.
    Type: Grant
    Filed: September 10, 2002
    Date of Patent: April 10, 2007
    Assignee: Headway Technologies, Inc.
    Inventors: Simon Liao, Kochan Ju, Youfeng Zheng
  • Patent number: 7189438
    Abstract: A magnetic recording medium has a recording layer, disposed above a surface of a substrate and made of hard magnetic nano-particles. The hard magnetic nano-particles are made of an alloy having as a main component an element selected from a group consisting of FePt, FePd and CoPt, and the hard magnetic nano-particles have axes of easy magnetization oriented in a direction approximately perpendicular to the surface of the substrate.
    Type: Grant
    Filed: May 14, 2004
    Date of Patent: March 13, 2007
    Assignee: Fujitsu Limited
    Inventors: Satoru Momose, Hiroyoshi Kodama, Nobutaka Ihara
  • Patent number: 7153546
    Abstract: Provided are a double-layer perpendicular magnetic recording medium having a high medium S/N at an areal recording density of 50 Gbits or more per square inch, and a magnetic storage apparatus having excellent reliability with a low error rate. The perpendicular magnetic recording medium is formed by sequentially laminating a domain control layer, an amorphous soft magnetic underlayer, an intermediate layer, and a perpendicular recording layer on a substrate. The domain control layer is a triple-layer film formed by laminating a first polycrystalline soft magnetic layer, a disordered antiferromagnetic layer, and a second polycrystalline soft magnetic layer from a substrate side.
    Type: Grant
    Filed: March 3, 2004
    Date of Patent: December 26, 2006
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Kiwamu Tanahashi, Atsushi Kikugawa, Noboru Shimizu, Yukio Honda, Yuzuru Hosoe
  • Patent number: 7112354
    Abstract: An apparatus includes a low magnetic-coercivity layer of material (LMC layer) having a majority electron-spin-polarization (M-ESP), an energy-gap coupled with the LMC layer, wherein a flow of spin-polarized electrons having an electron-spin-polarization anti-parallel to the LMC layer are injected via the energy-gap, to change the M-ESP of the LMC layer. A non-magnetic material is in electrical communication with the LMC layer and provides a spin-balanced source of current to the LMC layer, responsive to the injection of spin-polarized electrons into the LMC layer.
    Type: Grant
    Filed: February 3, 2005
    Date of Patent: September 26, 2006
    Assignee: Intel Corporation
    Inventors: Eric C. Hannah, Michael A. Brown
  • Patent number: 7072209
    Abstract: A magnetic memory element includes a sense structure, a tunnel barrier adjacent the sense structure, and a synthetic antiferromagnet (SAF) adjacent the tunnel barrier on a side opposite the sense structure. The SAF includes an antiferromagnetic structure adjacent a ferromagnetic seed layer. The ferromagnetic seed layer provides a texture so that the antiferromagnetic structure deposited on the ferromagnetic seed layer has reduced pinning field dispersion.
    Type: Grant
    Filed: December 29, 2003
    Date of Patent: July 4, 2006
    Assignee: Micron Technology, Inc.
    Inventor: James G. Deak
  • Patent number: 7033685
    Abstract: A method of manufacturing a perpendicular magnetic recording medium, comprises steps of: (a) providing a substrate of an amorphous thermoplastic polymer material having softening and glass transition temperatures as low as about 95° C.; and (b) forming at least one stack of thin film layers atop at least one surface of the substrate, the at least one layer stack including at least one granular magnetic recording layer of perpendicular type, wherein oxides and/or nitrides provide physical de-coupling of adjacent magnetic grains; and wherein each of the thin film layers is formed by depositing at a substrate temperature not greater than about 70° C., and the coercivity (Hc) of the resultant perpendicular magnetic recording medium is at least about 4,000 Oe.
    Type: Grant
    Filed: October 7, 2003
    Date of Patent: April 25, 2006
    Assignee: Seagate Technology LLC
    Inventors: Jean L. Lee, Thomas P. Nolan, Hong Ying Wang, Gary C. Rauch
  • Patent number: 7022383
    Abstract: Although it is known that exchange bias can be utilized in abutted junctions for longitudinal stabilization, a relatively large moment is needed to pin down the sensor edges effectively. Due to the inverse dependence of the exchange bias on the magnetic layer thickness, a large exchange bias has been difficult to achieve by the prior art. This problem has been solved by introducing a structure in which the magnetic moment of the bias layer has been approximately doubled by pinning it from both above and below through exchange with antiferromagnetic layers. Additionally, since the antiferromagnetic layer is in direct abutted contact with the free layer, it acts directly to help stabilize the sensor edge, which is an advantage over the traditional magnetostatic pinning that had been used.
    Type: Grant
    Filed: October 22, 2002
    Date of Patent: April 4, 2006
    Assignee: Headway Technologies, Inc.
    Inventors: Yun-Fei Li, Hui-Chuan Wang, Chyu-Jiuh Torng, Cherng-Chyi Han, Mao-Min Chen
  • Patent number: 6994895
    Abstract: A method of producing a magnetic recording medium including the steps of preparing alloy particles capable of forming a CuAu type or Cu3Au type ferromagnetic order alloy phase, forming an alloy particle layer on a support using the alloy particles, oxidizing the alloy particles, and annealing the alloy particle layer in a magnetic field under a reducing atmosphere. Also disclosed is a magnetic recording medium produced by the method, that is, a magnetic recording medium including a magnetic layer which contains magnetic particles in a CuAu type or Cu3Au type ferromagnetic order alloy phase and which has a squareness ratio of 0.75 or higher.
    Type: Grant
    Filed: July 1, 2003
    Date of Patent: February 7, 2006
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yasushi Hattori, Koukichi Waki
  • Patent number: 6858328
    Abstract: A master information carrier with excellent durability is provided, for the use of static and a real lump-sum recording of digital information signals on magnetic recording medium. The master information carrier comprises a non-magnetic substrate on which a ferromagnetic film is disposed with an embossed pattern. Protrusions of the embossed pattern correspond to a disposition of the digital information signals. Recessed portions of the embossed pattern of the ferromagnetic film are filled with non-magnetic solid material. Alternately, A non-magnetic substrate has an embossed pattern and recessed portions of the embossed pattern correspond to a disposition of the digital information signals. A ferromagnetic film is filled in the recessed portions of the embossed pattern.
    Type: Grant
    Filed: March 18, 1999
    Date of Patent: February 22, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuaki Ishida, Kiyokazu Tohma, Keizo Miyata, Yoriko Takai, Taizou Hamada, Hiroshi Ryonai
  • Patent number: 6824835
    Abstract: A flexible magnetic recording medium to which data is transferred by being brought into intimate contact with a master carrier which has a land/groove pattern corresponding to the data and also has a surface whose Moh's hardness is 6 to 10. The magnetic recording medium includes a substrate, a non-magnetic layer, and a magnetic layer. The non-magnetic layer and the magnetic layer are coated on the substrate in the recited order. The magnetic layer contains an abrasive comprising diamond particles whose average particle size is 0.03 to 0.5 &mgr;m. The diamond particle content of the abrasive is in a range of 0.1 to 5 wt % of ferromagnetic powder contained in the magnetic layer.
    Type: Grant
    Filed: December 12, 2002
    Date of Patent: November 30, 2004
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hitoshi Noguchi, Kazuhiro Niitsuma
  • Patent number: 6821574
    Abstract: A multiple layer magnetic recording medium exhibiting a marked increase in skirt signal-to-noise ratios, and a method of manufacturing such magnetic recording medium including the steps of forming a lower support layer and a magnetic layer on the substrate; transporting the magnetic recording medium on a non-magnetic carrier in a transport direction; exposing the magnetic recording medium to a first magnetic field of up to about 2500 gauss when the average percent solids of the multiple layers is less than 40% collectively, and exposing the magnetic recording medium to at least one additional magnetic field of from about 3500 to about 7000 gauss as the magnetic recording medium continues to transport when the average percent solids of said multiple layers is from about 43% to about 60% collectively, wherein the magnetic pigment particles in said magnetic layer are oriented in a longitudinal direction.
    Type: Grant
    Filed: February 14, 2003
    Date of Patent: November 23, 2004
    Assignee: Imation Corp.
    Inventors: Stephen R. Ebner, Guy Tadlock
  • Patent number: 6790378
    Abstract: The present invention includes coating composition having magnetic properties for application to a substrate. The coating composition includes a plurality of strontium and or barium hexaferrite particles having a random magnetic pole alignment. The coating composition also includes a binder adhesive capable of suspending the strontium hexaferrite particles. The binder adhesive is a natural rubber capable of adhering in a substantially thin film to the substrate. The strontium hexaferrite particles are normally present between 50% to 98% of the coating composition's total weight when dried on the substrate. The thickness of the film of the coating composition ranges from 0.5 mils to 20 mils, and has 6 to 24 magnetic pole changes per linear inch. The binder adhesive allows for manipulation of the strontium hexaferrite particles to a non-random magnetic pole alignment after the ferromagnetic particles have dried in the binder adhesive on the substrate.
    Type: Grant
    Filed: October 5, 2001
    Date of Patent: September 14, 2004
    Inventors: R. William Graham, Daniel F. Peters, Charles E. Adams, Ricky L. Helton
  • Patent number: 6783798
    Abstract: Thin, flexible composite materials, which are magnetic or magnetizable and processes for producing and using the materials. The composite material contains a laminate formed from a mixture of magnetic or magnetizable particles, binder particles (and optionally active particles), applied to and fused and/or coalesced with a first substrate. The composite preferably contains an additional second substrate fused to and/or coalesced with, the laminate on the side of the laminate opposite that of the first substrate.
    Type: Grant
    Filed: June 6, 2003
    Date of Patent: August 31, 2004
    Assignee: Koslow Technologies Corporation
    Inventor: Evan E. Koslow
  • Patent number: 6773765
    Abstract: Disclosed is a process for making a flexible magnet with an induced anisotropy, and in particular to a process for making a flexible anisotropic magnet by thermal spraying in the presence of an applied magnetic field. The method may be used to fabricate a substrate having a flexible anisotropic magnetic coating or a free standing anisotropic flexible magnet.
    Type: Grant
    Filed: November 4, 1999
    Date of Patent: August 10, 2004
    Assignee: The Research Foundation of State University of New York
    Inventors: Richard J. Gambino, Dongil Shin, Jeffrey A. Brogan
  • Patent number: 6753043
    Abstract: A servo-patterned magnetic recording medium, comprising: a magnetic layer having a surface with substantially uniform topography, the magnetic layer including a data zone and a servo pattern, the servo pattern comprising: (a) a first patterned plurality of regions of first, higher values of magnetic coercivity Hc and magnetic remanence-thickness product Mrt; and (b) a second patterned plurality of ion-implanted regions of second, lower values of Hc. and Mrt; wherein the second, lower values of Hc and Mrt are sufficiently lower than the first, higher values of Hc and Mrt as to permit sensing for enabling accurate positioning of a read/write transducer head in the data zone but sufficiently high for providing the medium with thermal stability, high amplitude of magnetic transition, and high signal-to-noise ratio.
    Type: Grant
    Filed: October 12, 2001
    Date of Patent: June 22, 2004
    Assignee: Seagate Technology LLC
    Inventors: David S. Kuo, Xinwei Li
  • Patent number: 6749904
    Abstract: High areal storage density, patterned magnetic media comprising a patterned plurality of at least partially crystalline, ferromagnetic particles or grains are provided by means of a simple, economical process wherein a non-magnetic substrate is provided with a layer of an amorphous, paramagnetic or anti-paramagnetic material comprising at least one component, e.g., a metal element, which is ferromagnetic when in at least partially crystalline form, and at least partially crystallizing the at least one component at selected areas of the amorphous layer to form a spaced-apart pattern of at least partially crystallized, ferromagnetic particles or grains of the at least one component, the particles or grains being spaced apart and surrounded by a matrix of the amorphous material. Embodiments include utilizing a focussed or scanned laser source and an amorphous Ni—P layer for forming ferromagnetic Ni particles or grains.
    Type: Grant
    Filed: May 6, 2002
    Date of Patent: June 15, 2004
    Assignee: Seagate Technology LLC
    Inventors: Connie Chunling Liu, Li-Ping Wang, Linda Lijun Zhong, Jeffery Lee Petrehn
  • Patent number: 6716489
    Abstract: A manufacturing method of a domain wall displacement type magneto-optical recording medium comprises the steps of depositing a magnetic layer on a substrate to prepare a disc, and irradiating the magnetic layer with a converged light beam while applying a magnetic field and annealing the magnetic layer a converged light beam between information tracks.
    Type: Grant
    Filed: January 14, 2002
    Date of Patent: April 6, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yasuyuki Miyaoka
  • Patent number: 6716488
    Abstract: A ferrite layer formation process that may be performed at a lower temperature than conventional ferrite formation processes. The formation process may produce highly anisotropic structures. A ferrite layer is deposited on a substrate while the substrate is exposed to a magnetic field. An intermediate layer may be positioned between the substrate and the ferrite to promote bonding of the ferrite to the substrate. The process may be performed at temperatures less than 300° C. Ferrite film anisotropy may be achieved by embodiments of the invention in the range of about 1000 dyn-cm/cm3 to about 2×106 dyn-cm/cm3.
    Type: Grant
    Filed: June 22, 2001
    Date of Patent: April 6, 2004
    Assignee: Agere Systems Inc.
    Inventors: Debra Anne Fleming, Gideon S. Grader, David Wilfred Johnson, Jr., John Thomson, Jr., Robert Bruce Van Dover
  • Patent number: 6709773
    Abstract: A perpendicular magnetic recording medium having a substrate, a seedlayer on the substrate and a magnetic underlayer on the seedlayer, the magnetic underlayer having an easy axis of magnetization substantially directed in a radial or transverse direction, and a process for manufacturing the perpendicular magnetic recording medium are disclosed.
    Type: Grant
    Filed: June 5, 2001
    Date of Patent: March 23, 2004
    Assignee: Seagate Technology, Inc.
    Inventors: Chung-Hee Chang, Rajiv Y. Ranjan
  • Publication number: 20030122252
    Abstract: After a barrier film is formed on a pad electrode, Ni particles having a diameter of 2 &mgr;m or less are selectively deposited on the barrier film, thereby forming a Ni fine particle film. Then, a bump electrode made of a solder ball is provided on the pad electrode through the Ni fine particle film. Thereafter, the bump electrode is melted by a heat treatment to join the Ni fine particle film to the bump electrode. Thus, a bump electrode structure is finished.
    Type: Application
    Filed: December 9, 2002
    Publication date: July 3, 2003
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Atsuko Sakata, Keiichi Sasaki, Nobuo Hayasaka, Katsuya Okumura, Hirotaka Nishino
  • Patent number: 6572934
    Abstract: In manufacturing a magnetic recording disk, a magnetic film for a recording layer is deposited on a substrate of the magnetic recording disk in a magnetic-film deposition chamber, and the substrate is transferred from the magnetic-film deposition chamber to a lubricant-layer preparation chamber without exposing the substrate to the atmosphere. Then, a lubricant layer is prepared on the substrate in the lubricant-layer preparation chamber.
    Type: Grant
    Filed: February 1, 2001
    Date of Patent: June 3, 2003
    Assignees: Anelva Corporation, Nihon Micro Coating Co., Ltd.
    Inventors: Naoki Watanabe, Nobuyoshi Watanabe, Kazunori Tani, Shinji Furukawa, Hiromi Sasaki, Osamu Watabe
  • Publication number: 20030077465
    Abstract: A method of forming a magnetic assembly having at least one magnetic layer having dimensions of thickness, width and length, and at least one printable substrate layer having dimensions of thickness, width and length, including the steps of providing a molten magnetic composition including about 70 wt-% to about 95 wt-% of at least one magnetic material and about 5 wt-% to about 30 wt-% of at least one thermoplastic binder, forming the magnetic composition into a magnetic layer at an elevated temperature and directly applying the magnetic layer at an elevated temperature to a first surface of a printable substrate layer wherein. An adhesion promoting composition may be further provided between the magnetic layer and the printable substrate layer for improving adhesion between the magnetic layer and the printable substrate layer.
    Type: Application
    Filed: October 18, 2002
    Publication date: April 24, 2003
    Inventors: Randall Boudouris, Raymond Richards
  • Publication number: 20030030027
    Abstract: The present invention includes magnetizable coating composition for application to a substrate. The coating composition includes a plurality of strontium and or barium hexaferrite particles having a random magnetic pole alignment. The coating composition also includes a binder adhesive capable of suspending the strontium hexaferrite particles. The binder adhesive is a latex capable of adhering in a substantially thin film to the substrate. The strontium hexaferrite particles are normally present between 50% to 98% of the coating composition's total weight when dried on the substrate. The thickness of the film of the coating composition is at least about 0.5 mils thick, and has 6 to 24 magnetic pole changes per linear inch. The binder adhesive allows for manipulation of the strontium hexaferrite particles to a non-random magnetic pole alignment after the ferromagnetic particles have dried in the binder adhesive on the substrate.
    Type: Application
    Filed: July 31, 2001
    Publication date: February 13, 2003
    Inventors: R. William Graham, Daniel F. Peters, Charles E. Adams, Ricky L. Helton