Having Specified Pits, Tracks, Or Indicia Patents (Class 428/848.5)
  • Patent number: 8786971
    Abstract: According to one embodiment, there is provided a magnetic recording apparatus including a head slider including read and write elements, and a magnetic recording medium including magnetically recordable recording tracks with a width L1, a wide land track with a width L2 larger than the width L1 of the recording track, and non-recording sections with a width G1 each provided between adjacent recording tracks. The width L1 of the recording track is smaller than a bottom read width BRW of the read and write elements, and the width L2 of the wide land track is larger than the bottom read width BRW of the read and write elements.
    Type: Grant
    Filed: February 7, 2014
    Date of Patent: July 22, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masatoshi Sakurai, Kazuto Kashiwagi, Naoki Tagami
  • Patent number: 8593751
    Abstract: The invention is a patterned-media disks for multi-track recording that are fabricated by nanoimprinting from a master template and that have data islands arranged in a pattern to compensate for head skew. The islands are arranged along lines canted relative to a disk radial line by an acute angle, as required for multi-track recording. However, this angle is not the same for all bands, but varies from band to band to compensate for head skew. The angle the lines in a band are canted is reduced by the amount of head skew. There are a plurality of bands between the disk inside-diameter (ID) and mid-diameter (MD) where the angle is in one direction from a radial line and a plurality of bands between the disk MD and outside-diameter (OD) where the angle is in the opposite direction from a radial line.
    Type: Grant
    Filed: November 30, 2011
    Date of Patent: November 26, 2013
    Assignee: HGST Netherlands B.V.
    Inventor: Thomas R. Albrecht
  • Patent number: 8420239
    Abstract: A recessed field is formed surrounding resist columns that are in a pattern of bit patterned magnetic media. A filler layer is formed in the recessed field. The resist columns are removed to leave recesses in the filler layer that replicate the pattern. Bit patterned magnetic media is formed in the recesses.
    Type: Grant
    Filed: August 16, 2011
    Date of Patent: April 16, 2013
    Assignee: Seagate Technology LLC
    Inventor: Sethuraman Jayashankar
  • Patent number: 8274277
    Abstract: A high-resolution magnetic encoder system includes a magnetic resistive sensor, a fixed suspension, and a mechanism. The magnetic resistive sensor is mounted to the fixed suspension above a magnetic medium having at least one magnetic track. The fixed suspension is attached to the mechanism, such as a housing, a substrate, and/or an electronic board. The sensor is adapted to perform a relative movement with respect to and in close contact to the surface of the magnetic medium. The magnetic medium may be protected by an overcoat layer. The magnetic resistive sensor may be Giant Magnetic-Resistive (GMR) sensor and/or a Tunneling Magnetic-Resistive Sensor (TMR).
    Type: Grant
    Filed: August 29, 2009
    Date of Patent: September 25, 2012
    Assignee: International Business Machines Corporation
    Inventors: Andreas Dietzel, Marcus Breuer, Hubert Grimm, Karl-Heinz Lehnhert, Nikolaus Luckner, Rolf Schaefer, Guenther Michaelis
  • Publication number: 20120075747
    Abstract: A hard disk drive has a magnetic media disk comprising a substrate having an axis, and an exchange coupled, bit patterned media on the substrate arranged in a plurality of tracks. Each of the tracks has a pattern of islands extending in an axial direction from the disk. Each island comprises a first layer having a first anisotropy and a first layer radial width, and a second layer on the first layer and having a second anisotropy that is lower than the first anisotropy. The second layer radial width is less than the first layer radial width.
    Type: Application
    Filed: September 28, 2010
    Publication date: March 29, 2012
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Elizabeth A. Dobisz, Michael K. Grobis, Olav Hellwig, Dieter K. Weller
  • Patent number: 8116022
    Abstract: According to one embodiment, a magnetic recording apparatus includes a magnetic recording medium including magnetically recordable recording tracks with a width L1, non-recording sections each provided between adjacent recording tracks, and a wide land track having a width L2 larger than the width L1 of the recording tracks, and a head slider including read and write heads.
    Type: Grant
    Filed: April 23, 2010
    Date of Patent: February 14, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masatoshi Sakurai, Kazuto Kashiwagi
  • Publication number: 20110300410
    Abstract: A recessed field is formed surrounding resist columns that are in a pattern of bit patterned magnetic media. A filler layer is formed in the recessed field. The resist columns are removed to leave recesses in the filler layer that replicate the pattern. Bit patterned magnetic media is formed in the recesses.
    Type: Application
    Filed: August 16, 2011
    Publication date: December 8, 2011
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventor: Sethuraman Jayashankar
  • Patent number: 8059368
    Abstract: It is possible to improve the recording and reproducing S/N ratio, the reproduction signal intensity, and the degree of high density recording. There are provided a plurality of recording tracks formed on a substrate, each recording track being formed of a magnetic material, and non-recording sections formed on the substrate, each non-recording section separating adjacent recording tracks, each recording track including a plurality of recording sections and connecting sections for connecting the recording sections adjacent thereto in a track longitudinal direction, and each connecting section having a cross-sectional area in a track width direction that is smaller than a cross-sectional area in a track width direction of adjacent recording sections.
    Type: Grant
    Filed: June 2, 2010
    Date of Patent: November 15, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kaori Kimura, Masatoshi Sakurai, Akira Kikitsu, Yoshiyuki Kamata, Satoshi Shirotori, Hiroyuki Hieda
  • Publication number: 20110235215
    Abstract: A method for making a master mold that is used in the nanoimprinting process to make patterned-media disks with patterned data islands uses guided self-assembly of a block copolymer into its components. Conventional or e-beam lithography is used to first form a pattern of generally radial stripes on a substrate, with the stripes being grouped into annular zones or bands. A block copolymer material is then deposited on the pattern, resulting in guided self-assembly of the block copolymer into its components to multiply the generally radial stripes into generally radial lines. Various methods, including conventional lithography, guided self-assembly of a second block copolymer, and e-beam lithography, are then used to form concentric rings over the generally radial lines. After etching and resist removal, the master mold has a pattern of either pillars or holes, depending on the method used.
    Type: Application
    Filed: June 2, 2011
    Publication date: September 29, 2011
    Inventors: Elizabeth Ann Dobisz, Ricardo Ruiz
  • Patent number: 8021769
    Abstract: A patterned perpendicular magnetic recording medium has discrete magnetic islands, each of which has a recording layer (RL) structure that comprises two exchange-coupled ferromagnetic layers. The RL structure may be an “exchange-spring” RL structure with an upper ferromagnetic layer (MAG2), sometimes called the exchange-spring layer (ESL), ferromagnetically coupled to a lower ferromagnetic layer (MAG1), sometimes called the media layer (ML). The RL structure may also include a coupling layer (CL) between MAG1 and MAG2 that permits ferromagnetic coupling. The interlayer exchange coupling between MAG1 and MAG2 may be optimized, in part, by adjusting the materials and thickness of the CL. The RL structure may also include a ferromagnetic lateral coupling layer (LCL) that is in contact with at least one of MAG1 and MAG2 for mediating intergranular exchange coupling in the ferromagnetic layer or layers with which it is in contact (MAG2 or MAG1).
    Type: Grant
    Filed: May 22, 2007
    Date of Patent: September 20, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Andreas Klaus Berger, Eric E. Fullerton, Olav Hellwig, Byron Hassberg Lengsfield, III, Ernesto E. Marinero
  • Publication number: 20110200846
    Abstract: A method of manufacturing a magnetic recording medium having a discrete track structure enables the discrete track structure to be fabricated in a simple method with good productivity while maintaining satisfactory accuracy of the discrete track structure and holding favorable magnetic separation performance between tracks. The method comprises steps of: forming an aluminum film on a nonmagnetic substrate; executing an anodizing process on the aluminum film to form an alumina layer including nano-holes in a self-organizing manner; forming a resist pattern exposing recording track regions; and depositing a magnetic material in the nano-holes in the recording track regions. The method can further comprise a step of forming recessed parts at positions of the nano-holes to be formed in the anodizing process. The method can further comprise a step of forming a first underlayer of titanium and a second underlayer of gold.
    Type: Application
    Filed: September 7, 2010
    Publication date: August 18, 2011
    Applicant: Fuji Electric Device Technology Co., Ltd.
    Inventor: Hitoshi NAKATA
  • Publication number: 20110122526
    Abstract: A manufacturing method of a magnetic recording medium includes: forming a magnetic film having an artificial lattice structure by laminating plural types of atomic layers alternately on a substrate; and separating dots, which forms a dot separation band by implanting an ion, to reduce saturation magnetization locally, into portions of the magnetic film other than plural portions of the magnetic film. Each of the plural portions is made into a magnetic dot in which information is to be magnetically recorded. The saturation magnetization of the dot separation band is smaller than that of the magnetic dot.
    Type: Application
    Filed: July 16, 2009
    Publication date: May 26, 2011
    Applicant: ULVAC, INC.
    Inventors: Kenji Sato, Tsutomu Tanaka, Tsutomu Nishihashi, Tadashi Morita, Kazuhiro Watanabe
  • Publication number: 20110085267
    Abstract: A recording media design having discrete track recording structure where the trenches between tracks are filled with a soft magnetic material is provided. The soft magnetic material provides a low magnetic impedance path to the soft underlayer such that fringe fields from the write head are conducted to the soft underlayer without having a negative effect such as adjacent track erasure. A method of manufacturing the media includes a nano-imprint step and ion milling out the data layer to create the trenches. A B2O3 material allows the data layer to be ion milled out without redeposition bridging the B2O3 layer thus preventing lift off of the mask. The trenches are then filled by ion deposition with the layers of ferromagnetic material separated by an anti-ferromagnetic coupling that causes the flux to be conducted to the soft underlayer and remnant flux to rotate within the island and not into adjacent tracks.
    Type: Application
    Filed: December 14, 2010
    Publication date: April 14, 2011
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Mourad Benakli, Michael Mallary
  • Patent number: 7846567
    Abstract: The present invention provides a magnetic disk in a discrete track medium and a patterned medium, which prevents the loss of the magnetically recorded data when a head of a magnetic disk device contacts the magnetic disk, and a manufacturing method thereof. A magnetic disk has a protrusion as a non-magnetic member formed on a disk surface to prevent a head from being in contact with a recording section. When the protrusion formed in a disk substrate collides against the head, the protrusion 7 does not collapse, and accordingly, the recording layer is not damaged. Alternatively, concave and convex portions are formed on the substrate surface to use the convex portion as the protrusion.
    Type: Grant
    Filed: May 28, 2008
    Date of Patent: December 7, 2010
    Assignee: Hitachi, Ltd.
    Inventors: Yasutaka Okura, Tomio Iwasaki
  • Patent number: 7835094
    Abstract: A bit-patterned magnetic media (BPM) includes with respect to each data track regular bit-islands having a first size and large bit-islands having a second size. The placement of the regular bit-islands and large bit-islands within each data track results in a unique pattern. An amplitude-modulated readback signal is generated in response to a transducer head moving over the bit-patterned media. Based on the amplitude-modulated readback signal, channel response circuitry detects the pattern of regular bit-islands and large bit-islands associated with a particular data track. Based on the detected pattern, the channel response circuitry is able to uniquely identify the data track.
    Type: Grant
    Filed: July 2, 2008
    Date of Patent: November 16, 2010
    Assignee: Seagate Technology LLC
    Inventor: Mark David Bedillion
  • Publication number: 20100233517
    Abstract: A method for making a master disk to be used for nanoimprinting patterned-media magnetic recording disks uses sidewall lithography. In one implementation, the master disk substrate has a first pattern of concentric rings formed on it by sidewall lithography, followed by a second pattern of generally radially-directed pairs of parallel lines, also formed by sidewall lithography, with the pairs of parallel lines intersecting the rings. An etching process is then performed, using the upper pattern as an etch mask, to remove unprotected portions of the underlying concentric rings. This leaves a pattern of pillars on the substrate, which then serve as an etch mask for an etching process that etches unprotected portions of the master disk substrate. The resulting master disk then has pillars of substrate material arranged in a pattern of concentric rings and generally radially-directed pairs of parallel lines.
    Type: Application
    Filed: May 27, 2010
    Publication date: September 16, 2010
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventor: Thomas R. Albrecht
  • Publication number: 20100221582
    Abstract: Provided is a magnetic recording medium substrate appropriate for a discrete medium and capable of fabricating a magnetic recording medium to/from which data can be written or read stably. Coaxial grooves (2) are formed on the surface of a resin substrate (1). The groove (2) has a width (T2) greater than a width (T1) of a track (3). Accordingly, when a magnetic layer is layered on the resin substrate (1), magnetic layers formed on the adjacent tracks (3) are not brought into contact and it is possible to prevent the problem that the magnetic layer is embedded in the groove (2). Thus, it is possible to physically separate the track (3) by the groove (2) and fabricate a magnetic recording medium to/from which data can written and read stably.
    Type: Application
    Filed: December 13, 2006
    Publication date: September 2, 2010
    Inventors: Hideki Kawai, Kouichi Takikawa, Shigeru Hosoe, Satoshi Nakano, Hiroyuki Hattori, Yoshiharu Masaki
  • Publication number: 20100173177
    Abstract: To provide a mold structure used to produce a discrete track medium, including in a surface of the mold structure: a plurality of line pattern forming concave portions which are positioned so as to be adjacent and substantially parallel to each other; and a communicating concave portion which is positioned so as to intersect the line pattern forming concave portions and connects the line pattern forming concave portions.
    Type: Application
    Filed: January 6, 2010
    Publication date: July 8, 2010
    Applicant: FUJIFILM CORPORATION
    Inventors: Satoshi WAKAMATSU, Tadashi OMATSU
  • Publication number: 20100157772
    Abstract: A data storage device comprises a substrate having oppositely disposed surfaces and a plurality of volumes arranged along tracks between the surfaces; a plurality of micro-holograms each contained in a corresponding one of the volumes; and, at least one groove in at least one of the surfaces and being operative to diffract light through the at least one surface and into the volumes; wherein, the presence or absence of a micro-hologram in a stacked layer in each of the volumes is indicative of a corresponding portion of data stored.
    Type: Application
    Filed: December 23, 2008
    Publication date: June 24, 2010
    Applicant: General Electric Company
    Inventors: Pingfan Peter Wu, Brian Lee Lawrence, Zhiyuan Ren, John Erik Hershey, Xiaolei Shi, Kenneth Brakeley Welles, John Anderson Fergus Ross, Victor Petrovich Ostroverkhov
  • Patent number: 7682713
    Abstract: The magnetic recording medium includes: recording elements formed as the convex portions of the recording layer formed in the predetermined concavo-convex pattern over a substrate; and a filling elements with which a concave portions between the recording elements are filled. A surface concave portion is formed in a surface of the magnetic recording medium above the recording element. The surface concave portion has a cross-sectional shape of which a portion corresponding to a center of the recording element lying thereunder in a width direction thereof is recessed deepest toward the substrate, and has a width monotonically increasing with increase of a distance from the substrate.
    Type: Grant
    Filed: September 12, 2005
    Date of Patent: March 23, 2010
    Assignee: TDK Corporation
    Inventors: Takahiro Suwa, Kazuhiro Hattori, Shuichi Okawa
  • Patent number: 7675699
    Abstract: A patterned-media magnetic recording disk has data islands arranged into concentric data tracks and the data tracks arranged into radially-spaced annular zones, with each zone having an inside-diameter (ID) perimeter and an outside-diameter (OD) perimeter and at least one annular nondata region near one of its perimeters. Each zone includes generally radially-directed synchronization (sync) marks that extend from the zone ID perimeter to the zone OD perimeter so as to extend into the annular nondata region or regions of the zone. In the disk drive that uses the patterned-media disks the read head and write head have an effective radial offset relative to one another, so the write head may be on a data track near a zone perimeter when the read head is located in a nondata region. The read head detects the sync marks that extend into the nondata region so that the write head can be synchronized with the data islands in the data track.
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: March 9, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Thomas R. Albrecht
  • Patent number: 7636215
    Abstract: On a magnetic recording medium, data track patterns and servo patterns are formed on one surface and another surface of a disk-shaped substrate by patterns including recording regions and non-recording regions.
    Type: Grant
    Filed: January 11, 2008
    Date of Patent: December 22, 2009
    Assignee: TDK Corporation
    Inventors: Mitsuru Takai, Shuichi Okawa
  • Patent number: 7635529
    Abstract: According to one embodiment, a substrate for a magnetic recording media has circumferential protrusions corresponding to recording tracks and circumferential recesses corresponding to grooves between the recording tracks, in which the substrate satisfying at least one of conditions of (a) a surface of the recess has a surface energy smaller than that of the protrusion, (b) the surface of the recess is modified with a thermally decomposable or deformable substance, (c) the surface of the recess has surface roughness smaller than that of the protrusion, (d) crystal orientation is more disturbed on the surface of the recess than on the protrusion, (e) the surface of the recess is modified with a substance that causes reaction with a magnetic material or that diffuses into the magnetic material, and (f) the surface of the recess is modified with a substance soluble in a solvent or with a deformable substance.
    Type: Grant
    Filed: June 28, 2006
    Date of Patent: December 22, 2009
    Assignees: Showa Denko K.K., Kabushiki Kaisha Toshiba
    Inventors: Katsuyuki Naito, Masatoshi Sakurai, Akira Kikitsu, Yoshiyuki Kamata, Naoko Kihara, Masahiro Oka
  • Publication number: 20090311558
    Abstract: A magnetic recording medium that includes: a disc-shaped substrate; and plural magnetization retainers arranged on the disc-shaped substrate in plural circulations around a center of the substrate, each of the magnetization retainers having a length in a circumferential direction in such a manner that the length becomes longer as closer to outer circumference at least in a predetermined area, each retaining magnetization individually, each being formed of a magnetic material having axis of easy magnetization of magnetocrystalline anisotropy in a direction perpendicular to front and back surfaces of the substrate, each being filled with an ion that weakens the magnetocrystalline anisotropy of the magnetic material such that an amount of ion implantation becomes less as closer to the outer circumference in the predetermined area.
    Type: Application
    Filed: March 20, 2009
    Publication date: December 17, 2009
    Applicant: FUJITSU LIMITED
    Inventor: Hiroto Takeshita
  • Patent number: 7630156
    Abstract: On a rotary-type magnetic recording medium, servo patterns are formed in servo pattern regions on one surface and the other surface of a disk-shaped substrate by patterns including recording regions and non-recording regions. In the servo pattern regions on both the one surface and the other surface, plural functional regions are defined in order in a direction of rotation of the magnetic recording medium. In the pattern formed in at least one region out of the plural functional regions on the one surface, the non-recording regions are formed at formation positions on the one surface corresponding to formation positions of the recording regions on the other surface and the recording regions are formed at formation positions on the one surface corresponding to formation positions of the non-recording regions on the other surface.
    Type: Grant
    Filed: January 11, 2008
    Date of Patent: December 8, 2009
    Assignee: TDK Corporation
    Inventors: Shuichi Okawa, Kazuhiro Hattori, Makoto Moriya
  • Patent number: 7615292
    Abstract: A magnetic recording medium having a recording layer formed in a concavo-convex pattern, which can allow a head to have stable flying characteristics. The recording layer is formed in a concavo-convex pattern, and concave portions of the concavo-convex pattern of the recording layer are filled with a non-magnetic material. The relationship of S?3.6×R holds, when R represents a concavo-convex ratio obtained by dividing an area of convex portions in a surface by an area of the concave portions in the surface, and S represents a difference in height between a concavity and a convexity of the surface. In the magnetic recording medium, an arithmetical mean deviation of the assessed profile of the surface is limited to 0.3 nm or more.
    Type: Grant
    Filed: March 18, 2005
    Date of Patent: November 10, 2009
    Assignee: TDK Corporation
    Inventors: Kuniyasu Ito, Kazuhiro Hattori
  • Publication number: 20090214898
    Abstract: Embodiments of the present invention help to produce discrete track media and bit patterned media having both excellent recording and reproducing performance and reliability. According to one embodiment, a manufacturing method forms a nonmagnetic layer mainly composed of the same element as a nonmagnetic element contained in magnetic recording layers and on the magnetic recording layers and a mask layer having apertures for forming more concentrated parts of the nonmagnetic element in the magnetic recording layers on the nonmagnetic layer. The method implants ions of the nonmagnetic element through the nonmagnetic layer masked by the mask layer to form the more concentrated parts of the nonmagnetic element in the magnetic recording layer.
    Type: Application
    Filed: February 10, 2009
    Publication date: August 27, 2009
    Inventors: Tatsuya Hinoue, Hiroshi Kanai, Toshinori Ono, Hiroyuki Suzuki, Hiroshi Inaba
  • Patent number: 7577079
    Abstract: The present invention provides a master disk with high flexibility and high close contact property with a slave disk to be transferred, which bears information to be transferred by magnetic transfer. When incident angle of X-ray is designated by ?, electroforming is performed such that X-ray diffraction pattern of the master substrate 11 has a 200 plane reflection at 2?=51.0° to 53.0°, and a 220 plane reflection at 2?=75.5° to 76.5°, and the reflection intensity ratio of X-ray diffraction of the 220 plane with respect to the 200 plane is I[220]/I[200]=2 to 30.
    Type: Grant
    Filed: March 17, 2006
    Date of Patent: August 18, 2009
    Assignee: FUJIFILM Corporation
    Inventors: Shiho Kamisawa, Kenji Ichikawa
  • Publication number: 20090166184
    Abstract: A track shield structure is disclosed that enables higher track density to be achieved in a patterned track medium without increasing adjacent track erasure and side reading. This is accomplished by placing a soft magnetic shielding structure in the space that is present between the tracks in the patterned medium. A process for manufacturing the added shielding structure is also described.
    Type: Application
    Filed: December 26, 2007
    Publication date: July 2, 2009
    Inventors: Yuchen Zhou, Lijie Guan, Kunliang Zhang
  • Publication number: 20090154017
    Abstract: A bit patterned magnetic media design for reducing the amount of magnetic material located in the trenches between topographic features is disclosed. An intermediate non-magnetic layer is deposited on the topography prior to depositing the functional magnetic layer on the topographic substrate features. The non-magnetic layer increases the width of the land regions that will ultimately support the functional magnetic layer. The non-magnetic layer also reduces the amount of trench deposition that can occur in the subsequent deposition of the magnetic recording layer. By eliminating most of the magnetic trench material, the amount of magnetic flux and readback interference produced by the trench material is reduced to an acceptable level.
    Type: Application
    Filed: December 17, 2007
    Publication date: June 18, 2009
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS BV
    Inventors: Thomas Robert Albrecht, Olav Hellwig
  • Patent number: 7482070
    Abstract: A magnetic recording medium having high reliability is provided, in which concave portions between recording elements formed as convex portions of a concavo-convex pattern are approximately completely filled with a non-magnetic material. The magnetic recording medium is a plate-like body including: a substrate; a recording layer that is formed in a predetermined concavo-convex pattern over the substrate and includes recording elements for recording information formed as convex portions of the concavo-convex pattern; and the non-magnetic material filling concave portions between the recording elements. Side faces of the recording elements are inclined to face a surface of the plate-like body on a side toward which the recording elements 16 project in the concavo-convex pattern. An inclination angle of the side faces of the recording elements with respect to a direction perpendicular to that surface is smaller than 90° and 5° or more.
    Type: Grant
    Filed: April 27, 2005
    Date of Patent: January 27, 2009
    Assignee: TDK Corporation
    Inventors: Mitsuru Takai, Yoshikazu Soeno, Katsumichi Tagami, Kazuya Shimakawa
  • Publication number: 20080292907
    Abstract: A patterned perpendicular magnetic recording medium has discrete magnetic islands, each of which has a recording layer (RL) structure that comprises two exchange-coupled ferromagnetic layers. The RL structure may be an “exchange-spring” RL structure with an upper ferromagnetic layer (MAG2), sometimes called the exchange-spring layer (ESL), ferromagnetically coupled to a lower ferromagnetic layer (MAG1), sometimes called the media layer (ML). The RL structure may also include a coupling layer (CL) between MAG1 and MAG2 that permits ferromagnetic coupling. The interlayer exchange coupling between MAG1 and MAG2 may be optimized, in part, by adjusting the materials and thickness of the CL. The RL structure may also include a ferromagnetic lateral coupling layer (LCL) that is in contact with at least one of MAG1 and MAG2 for mediating intergranular exchange coupling in the ferromagnetic layer or layers with which it is in contact (MAG2 or MAG1).
    Type: Application
    Filed: May 22, 2007
    Publication date: November 27, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Andreas Klaus Berger, Eric E. Fullerton, Olav Hellwig, Byron Hassberg Lengsfield, III, Ernesto E. Marinero
  • Publication number: 20080274381
    Abstract: A patterned perpendicular magnetic recording medium of the type that has spaced-apart pillars with magnetic material on their ends and with trenches between the pillars that are nonmagnetic regions is made with a method that allows use of a pre-etched substrate. A nonmagnetic capping layer is located in the trenches above the nonmagnetic regions. The substrate has diffusion material in the trenches that when heated will diffuse into the magnetic recording layer material and chemically react with it. The pillars are formed of material that will not diffuse into the recording layer. The recording layer is formed over the entire substrate and a nonmagnetic capping layer that is not chemically reactive with the diffusion material is formed over the recording layer in the trenches. The substrate is annealed to cause the recording layer material in the trenches and the material in the substrate to diffuse into one another and chemically react to render the trenches nonmagnetic.
    Type: Application
    Filed: May 1, 2007
    Publication date: November 6, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Eric E. Fullerton, Olav Hellwig
  • Patent number: 7351484
    Abstract: A high field contrast magnetic stamper/imprinter for use in patterning of magnetic and magneto-optical (MO) recording media by contact printing, comprises: (a) a layer of a magnetic material having a high saturation magnetization Bsat?˜1.2 and high permeability ??˜5, including a first, topographically patterned surface and a second surface opposite the first surface, the first, topographically patterned surface comprising a patterned plurality of spaced-apart recesses with a plurality of non-recessed areas therebetween, the topographical pattern corresponding to a magnetic pattern to be formed in a magnetic or MO recording medium; and (b) a layer of Ni on the second surface. A corrosion-resistant protective overcoat layer may be present on the topographically patterned surface. A method for manufacturing the stamper/imprinter is also disclosed.
    Type: Grant
    Filed: February 22, 2006
    Date of Patent: April 1, 2008
    Assignee: Seagate Technology LLC
    Inventors: Li-Ping Wang, David Kuo, Jing Gui, Koichi Wago
  • Patent number: 7195808
    Abstract: A system for marking the different sides of a substrate so that the different sides can be identified is disclosed. A substrate holder is used for marking a substrate during the film growth process so that the different sides of the substrate can be distinguished includes a set of fingers having a groove for holding the substrate. The fingers extend over a surface of the substrate for shielding incoming material being deposited onto the surface of the substrate leaving a portion of the surface uncovered. The fingers are positioned asymmetrically. The fingers include a first finger, a second finger, and a third finger, with a distance between said first finger and said second finger is less than the distance between said first finger and said third finger and is less than the distance between said second finger and said third finger.
    Type: Grant
    Filed: September 29, 2003
    Date of Patent: March 27, 2007
    Assignee: Seagate Technology, LLC
    Inventor: Chang Bok Yi
  • Patent number: 7183012
    Abstract: The invention provides a magnetic recording medium and a method of manufacturing the magnetic recording medium, in which a high density and good storage stability can be achieved by giving anisotropy in shape to a magnetic substance. A plan shape of the magnetic substance in the magnetic recording medium, which appears on the recording surface side, is an ellipse that is present within a rectangle and has a minor axis with a length equal to a short side of the rectangle. A quadrilateral defined by four intersects of two adjacent vertical rows and two adjacent horizontal rows, each of these rows comprising a plurality of pores, has a rectangular or rhombic shape.
    Type: Grant
    Filed: March 18, 2003
    Date of Patent: February 27, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tatsuya Saito, Tohru Den
  • Patent number: 7151641
    Abstract: A favorable magnetic transfer is performed to a perpendicular magnetic recording medium. A master medium is provided with a substrate on the surface of which protrusion portions, which form a pattern corresponding to the data that is to be transferred, having a pliable layer thereon have been formed. The master medium is further provided with a soft magnetic layer formed in the depression portions between the protrusion portions, and which is magnetically linked to the soft magnetic layer of the protrusion portions. The soft magnetic layer of the surface of the protrusion portions is conjoined with the magnetic recording layer of a perpendicular magnetic recording medium to form a conjoined body, and a transfer magnetic field is applied to the conjoined body in the direction from the substrate of the master medium toward the slave medium to perform the magnetic transfer.
    Type: Grant
    Filed: May 12, 2004
    Date of Patent: December 19, 2006
    Assignee: Fuij Photo Film Co., Ltd.
    Inventors: Masakazu Nishikawa, Kazunori Komatsu
  • Patent number: 7138193
    Abstract: An information storage medium with an array of laterally magnetized dots, as well as a process for producing this medium is disclosed. Each dot (2) contains at least one magnetic domain formed by a thin layer (4) of at least a magnetic material laterally covering this flat material and deposited at oblique incidence relative to the normal (z) to the plane (6) of the array. The invention applies in particular to computer hard drives.
    Type: Grant
    Filed: July 2, 2002
    Date of Patent: November 21, 2006
    Assignee: Commissariat A l'Energie Atomique
    Inventors: Bernard Rodmacq, Stéphane Landis, Bernard Dieny
  • Patent number: 7115328
    Abstract: The present invention provides a master disk that can easily be brought into contact with and separated from a magnetic recording medium, and can accommodate foreign matters. This master disk transfers a predetermined magnetic pattern onto a magnetic recording medium that can record magnetic information. In the master disk, there are a magnetic pattern formation region in which the magnetic pattern is formed, and a blank region in which the magnetic pattern is not formed. A concave portion for accommodating foreign matters is formed in at least one part of the blank region.
    Type: Grant
    Filed: April 19, 2002
    Date of Patent: October 3, 2006
    Assignee: Fujitsu Limited
    Inventors: Yutaka Nakamura, Hitoshi Komoriya, Hiroyuki Suzuki, Takao Hirahara
  • Patent number: 7105238
    Abstract: A master information carrier has on its surface an irregularity pattern representing information to be magnetically transferred to a magnetic recording medium held in contact with the surface of the master information carrier. The parts of the surface of the master information carrier which is brought into contact with the magnetic recording medium are in the range of 0.3 nm to 10.0 nm in center plane mean surface roughness SRa.
    Type: Grant
    Filed: August 7, 2003
    Date of Patent: September 12, 2006
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takako Ozawa, Masakazu Nishikawa