Cr Or Cr-base Underlayer Patents (Class 428/832.2)
  • Patent number: 11316101
    Abstract: A stack of the embodiment includes: a first magnetic substance; a second magnetic substance; and a first nonmagnetic substance which is disposed between the first magnetic substance and the second magnetic substance and contains at least one first metal element (M1) selected from the group consisting of ruthenium (Ru) and osmium (Os) and at least one second metal element (M2) selected from the group consisting of rhodium (Rh) and iridium (Ir). A magnetic device of the embodiment includes: a third magnetic substance; the stack; and a second nonmagnetic substance which is disposed between the third magnetic substance and the stack.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: April 26, 2022
    Assignee: KIOXIA CORPORATION
    Inventors: Rina Nomoto, Takayuki Tsukagoshi, Yasushi Nakasaki, Masaru Toko, Tadashi Kai, Takamitsu Ishihara
  • Patent number: 10672425
    Abstract: Disclosed herein are magnetic storage media with embedded disconnected circuits, and magnetic storage systems comprising such media. A magnetic storage media comprises a recording layer comprising a storage location, and an embedded disconnected circuit (EDC) configured to assist in at least one of writing to or reading from the storage location in response to a wireless activation signal. A magnetic storage system comprises a signal generator configured to generate a wireless activation signal, a magnetic storage media with a plurality of storage locations, and a write transducer and/or a read receiver. The magnetic storage media has at least one EDC configured to assist in writing to and/or reading from at least one of the plurality of storage locations in response to the wireless activation signal.
    Type: Grant
    Filed: June 26, 2018
    Date of Patent: June 2, 2020
    Assignee: Western Digital Technologies, Inc.
    Inventors: Pankaj Mehra, Bernd Lamberts, Sridhar Chatradhi, Jordan A. Katine
  • Patent number: 9704525
    Abstract: The magnetic tape includes a magnetic layer containing ferromagnetic hexagonal ferrite powder, abrasive, and binder on a nonmagnetic support, wherein the ferromagnetic hexagonal ferrite powder exhibits an activation volume of less than or equal to 1,800 nm3, and inclination, cos ?, of the ferromagnetic hexagonal ferrite powder relative to a surface of the magnetic layer as determined by sectional observation by a scanning electron transmission microscope is greater than or equal to 0.85 but less than or equal to 1.00.
    Type: Grant
    Filed: March 17, 2016
    Date of Patent: July 11, 2017
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • Patent number: 9228255
    Abstract: An FePt—C-based sputtering target contains Fe, Pt, and C and has a structure in which an FePt-based alloy phase and a C phase containing unavoidable impurities are mutually dispersed, the FePt-based alloy phase containing Pt in an amount of 40 at % or more and 60 at % or less with the balance being Fe and unavoidable impurities. The content of C is 21 at % or more and 70 at % or less based on the total amount of the target.
    Type: Grant
    Filed: June 23, 2014
    Date of Patent: January 5, 2016
    Assignee: TANAKA KIKINZOKU KOGYO K.K.
    Inventors: Takanobu Miyashita, Yasuyuki Goto, Ryousuke Kushibiki, Masahiro Aono, Masahiro Nishiura
  • Patent number: 9093100
    Abstract: A magnetic recording medium enabling excellent magnetic recording reproduction characteristics to be exhibited with the spacing loss reduced. The magnetic recording medium has a magnetic recording layer of a granular structure having nonmagnetic boundary portions between pillar-shaped magnetic particles on a nonmagnetic substrate, and an exchange coupling layer provided on the magnetic recording layer to add an action of exchange coupling the magnetic particles. Ion irradiation on the entire surface of the exchange coupling layer after layering the exchange coupling layer on the magnetic recording layer is performed.
    Type: Grant
    Filed: March 22, 2013
    Date of Patent: July 28, 2015
    Assignee: WD Media (Singapore) Pte. Ltd.
    Inventors: Junichi Yasumori, Yoshiaki Sonobe
  • Patent number: 8988828
    Abstract: A magnetic recording medium includes a substrate, a magnetic layer including an alloy having an L10 type crystal structure, and a plurality of underlayers arranged between the substrate and the magnetic layer. At least one of the plurality of underlayers is a soft magnetic underlayer formed by an alloy having a hexagonal close packed (hcp) structure and including Co metal or Co as its main component, with a (11•0) plane oriented parallel to a surface of the substrate.
    Type: Grant
    Filed: June 27, 2014
    Date of Patent: March 24, 2015
    Assignee: Showa Denko K.K.
    Inventors: Tetsuya Kanbe, Kazuya Niwa, Yuji Murakami, Lei Zhang
  • Patent number: 8792313
    Abstract: A magnetic recording medium of the present invention includes an under layer formed on a substrate, and a magnetic layer, formed on the under layer, which contains an alloy having an L10-type crystal structure as a main component. The under layer includes, in order from the substrate side, a first under layer with a lattice constant a of 2.87 ??a<3.04 ?, a second under layer having a BCC structure with a lattice constant a of 3.04 ??a<3.18 ?, a third under layer having a BCC structure with a lattice constant a of 3.18 ??a<3.31 ?, and an upper under layer having a NaCl-type crystal structure. The first under layer has a B2 structure, or has a BCC structure containing Cr as a main component. In the magnetic recording medium of the present invention, information is recorded using a heat-assisted magnetic recording type, or a microwave-assisted magnetic recording type.
    Type: Grant
    Filed: August 21, 2013
    Date of Patent: July 29, 2014
    Assignee: Showa Denko K.K.
    Inventors: Kazuya Niwa, Tetsuya Kanbe, Yuji Murakami, Lei Zhang
  • Patent number: 8390956
    Abstract: According to one embodiment, a perpendicular magnetic recording medium includes at least one soft magnetic underlayer above a substrate, a seed layer above the at least one soft magnetic underlayer, an intermediate layer above the seed layer, a magnetic recording layer above the intermediate layer, and an overcoat layer above the magnetic recording layer, wherein the seed layer includes a second seed layer above a first seed layer. In another embodiment, the seed layer is a multilayered structure of at least two cycles of a unit of layered film which includes a first seed layer and a second seed layer. The first seed layer includes a non-magnetic alloy having a Face-Centered-Cubic (FCC) structure, and the second seed layer includes a soft magnetic alloy having a FCC structure. Other structures are also disclosed, according to more embodiments.
    Type: Grant
    Filed: June 3, 2010
    Date of Patent: March 5, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Shun Tonooka, Reiko Arai, Hiroyuki Nakagawa, Kiwamu Tanahashi
  • Patent number: 8007931
    Abstract: A perpendicular magnetic recording medium including: a substrate; a perpendicular magnetic recording layer disposed over the substrate; a soft magnetic underlayer disposed between the substrate and the perpendicular magnetic recording layer; a shunting layer disposed under the soft magnetic underlayer; and an isolation layer disposed between the soft magnetic underlayer and the shunting layer and providing magnetic isolation between the shunting layer and the other layers disposed over the shunting layer are provided. The shunting layer is magnetically separated from the other magnetic layers disposed over the shunting layer, and shunts a magnetic field generated by the magnetic domain walls of the soft magnetic underlayer such that the magnetic field cannot reach a magnetic head, thereby increasing a signal-to-noise ratio (SNR).
    Type: Grant
    Filed: January 26, 2007
    Date of Patent: August 30, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hoo-san Lee, Chee-kheng Lim, Hoon-sang Oh, Sok-hyun Kong
  • Patent number: 7876530
    Abstract: In one embodiment, a magnetic recording medium comprises an underlying film, a magnetic film and a protective film formed in this order on a substrate. The magnetic film is a cobalt-base alloy film containing chromium and has a plurality of magnetic layers stacked without interposition of any non-magnetic layer. The plural magnetic layers comprise first, second and third magnetic layers. The first magnetic layer is disposed between the underlying film and the second magnetic layer. The second magnetic layer is disposed between the first magnetic layer and the third magnetic layer. The third magnetic layer is disposed between the second magnetic layer and the protective film. The concentration of chromium contained in the first magnetic layer is lower than that of chromium contained in the second magnetic layer. The thickness of the first magnetic layer is smaller than that of the second magnetic layer. The magnetic layers which overlie the first magnetic layer further contain platinum and boron.
    Type: Grant
    Filed: April 28, 2009
    Date of Patent: January 25, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Tatsuya Hinoue, Yotsuo Yahisa, Tomoo Yamamoto, Jo Inagaki, Hiroyuki Suzuki, Masae Suzuki, legal representative, Hidekazu Kashiwase
  • Patent number: 7550211
    Abstract: A magnetic recording medium includes an orientation adjusting layer, a nonmagnetic under layer, a nonmagnetic intermediate layer, a magnetic layer and a protective layer sequentially stacked on a nonmagnetic substrate provided on a first surface thereof with a texture streak and used for a magnetic disc. The nonmagnetic under layer contains at least a layer formed of a Cr—Mn-based alloy and possesses magnetic anisotropy having an axis of easy magnetization in a circumferential direction thereof. A magnetic recording and reproducing device includes the magnetic recording medium and a magnetic head for enabling information to be recorded in and reproduced from the magnetic recording medium.
    Type: Grant
    Filed: August 9, 2005
    Date of Patent: June 23, 2009
    Assignee: Showa Denko K.K.
    Inventors: Hiroshi Osawa, Shun Matsumoto, Daizo Endo
  • Patent number: 7545604
    Abstract: In one embodiment, a magnetic recording medium comprises an underlying film, a magnetic film and a protective film formed in this order on a substrate. The magnetic film is a cobalt-base alloy film containing chromium and has a plurality of magnetic layers stacked without interposition of any non-magnetic layer. The plural magnetic layers comprise first, second and third magnetic layers. The first magnetic layer is disposed between the underlying film and the second magnetic layer. The second magnetic layer is disposed between the first magnetic layer and the third magnetic layer. The third magnetic layer is disposed between the second magnetic layer and the protective film. The concentration of chromium contained in the first magnetic layer is lower than that of chromium contained in the second magnetic layer. The thickness of the first magnetic layer is smaller than that of the second magnetic layer. The magnetic layers which overlie the first magnetic layer further contain platinum and boron.
    Type: Grant
    Filed: December 22, 2005
    Date of Patent: June 9, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Tatsuya Hinoue, Yotsuo Yahisa, Tomoo Yamamoto, Joe Inagaki, Hiroyuko Suzuki, Hidekazu Kashiwase
  • Patent number: 7494727
    Abstract: A magnetic recording medium in which a recording layer is formed in a predetermined concavo-convex pattern and recording and reproducing apparatus comprising the magnetic recording medium are disclosed. The magnetic recording medium has a high areal density and high reliability since the occurrence of a crash of a magnetic head is suppressed. The magnetic recording medium comprises a recording layer formed over a substrate in a predetermined concavo-convex pattern to form recording elements as a convex portion of the concavo-convex pattern and a non-magnetic filler element filled in a concave portion between the recording elements. In this configuration, the top surface of the filler element is formed in a shape partially recessed toward the substrate side to form a groove having a width smaller than the width of the concave portion on the surface of the magnetic recording medium.
    Type: Grant
    Filed: July 25, 2005
    Date of Patent: February 24, 2009
    Assignee: TDK Corporation
    Inventors: Takahiro Suwa, Kazuya Shimakawa
  • Patent number: 7427446
    Abstract: A magnetic recording medium including a substrate, a first underlayer provided on the substrate, a first magnetic layer provided on the first underlayer, a nonmagnetic coupling layer provided on the first magnetic layer, and a second magnetic layer provided on the nonmagnetic coupling layer. The first and second magnetic layers are exchange-coupled, and have magnetizations that are mutually antiparallel in a state where no external field is applied to the magnetic recording medium. Additionally, the first underlayer is made of Cr or a Cr alloy each having a bcc crystal structure and including nitrogen, and further wherein the first underlayer has a thickness in a range of 0.5 nm to 6.0 nm.
    Type: Grant
    Filed: February 2, 2005
    Date of Patent: September 23, 2008
    Assignee: Fujitsu Limited
    Inventors: Reiko Murao, Masaya Suzuki
  • Publication number: 20080188165
    Abstract: A method for manufacturing a magnetic recording medium disk substrate is provided for achieving a magnetic disk having a suitable surface roughness, a high in-plane magnetic anisotropy and a high S/N. The manufacturing method has a texturing process wherein the magnetic recording medium disk substrate is rotated in the circumferential direction while a polishing tape is pressed against the rotating substrate. The polishing tape includes polyester fiber having a fiber diameter of 400 nm to 950 nm, on the surface coming into contact with the substrate. All the while, slurry including abrasive grains including a cluster diamond is supplied to the surfaces of the substrate. The present invention relates to a magnetic recording medium disk substrate produced by the manufacturing method; and a magnetic recording medium at least comprising a magnetic layer on the magnetic recording medium disk substrate and manufacturing method of the magnetic recording medium.
    Type: Application
    Filed: December 21, 2007
    Publication date: August 7, 2008
    Applicants: Fuji Electric Device Technology Co., Ltd., Teijin Fibers Limited
    Inventors: Shoji Sakaguchi, Hiroyuki Nakamura, Hideki Matsuo
  • Patent number: 7338725
    Abstract: An inplane magnetic recording medium having high S/N and thermal stability and a reliable magnetic storage device having surface recording density of 50 megabit/mm2 or more is described. The magnetic recording medium includes magnetic layers formed on a nonmagnetic substrate with a plurality of ground layers therebetween, at least one of the ground layers formed from an alloy of a body-centered cubic structure containing Cr as a main component and B of from 2 atomic % to 12 atomic %. Main components of the magnetic layers include a lower magnetic layer containing Co and Cr of from 10 atomic % to 16 atomic %, with film thickness of from 1.5 nm to 4.5 nm, and an upper magnetic layer containing Co, coupling anti-ferromagnetically with the lower magnetic layer through nonmagnetic intermediate layers.
    Type: Grant
    Filed: March 3, 2005
    Date of Patent: March 4, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Tetsuya Kanbe, Yotsuo Yahisa, Hiroyuki Suzuki, Hidekazu Kashiwase
  • Patent number: 7298588
    Abstract: A magnetic recording medium deposited on glass and having an orientation ratio greater than one is disclosed. The magnetic recording medium includes a CoW seedlayer deposited on a circumferentially textured glass substrate. The magnetic recording medium with such a seedlayer can have an OR that is similar or higher than that with a NiP seedlayer. Magnetic recording medium with a CoW seedlayer can produce oriented glass media with orientation ratio OR>1 when sputtered on substrates which have been circumferentially textured before the deposition of the CoW seedlayer. The W content of the CoW seedlayer can range between 30-50 at %. The thickness of the CoW seedlayer can range between 10 ? and 200 ?. The method for sputter depositing the magnetic recording medium is also disclosed and includes sputter depositing the CoW seedlayer using pure Ar as sputtering gas or using a mixture of Ar and O2, H2O and N2 as sputtering gas.
    Type: Grant
    Filed: June 15, 2004
    Date of Patent: November 20, 2007
    Assignee: Seagate Technology LLC
    Inventors: Li-Lien Lee, Shanghsien Rou, Romulo Ata
  • Patent number: 7141318
    Abstract: Magnetic recording media having improved magnetic properties such as an improved signal-to-noise ratio. The recording media includes a magnetic recording layer and an underlayer disposed beneath the magnetic recording layer. The underlayer is a Cr-based alloy such as CrMo that includes an additive selected from boron (B), silicon (Si) and boron nitride (BN). The additive preferentially segregates to the grain boundaries in the underlayer to reduce the grain size and grain size distribution in the underlayer.
    Type: Grant
    Filed: June 6, 2003
    Date of Patent: November 28, 2006
    Assignee: Maxtor Corporation
    Inventors: Gunn Choe, Mingjun Yu
  • Patent number: 7115330
    Abstract: A magnetic recording medium including a textured surface that is textured in a predetermined direction. The textured surface preferably has a distance ? between two mutually adjacent texturing lines satisfying a relationship 5<?<30 nm, and an angle ? between the textured surface and an oblique texture plane satisfying a relationship 0.5<?<7 degrees. There is also a Cr-based underlayer provided on the textured surface that has a preferred growth so that a number of grains having Cr<110> in a vicinity of 0 degrees or 90 degrees with respect to the predetermined direction is two times or greater than a number of grains having Cr<110> in a vicinity of 45 degrees with respect to the predetermined direction. Additionally, there is also a Co-based magnetic layer provided on the underlayer that has Co(1120) preferred growth along the predetermined direction.
    Type: Grant
    Filed: April 28, 2005
    Date of Patent: October 3, 2006
    Assignee: Fujitsu Limited
    Inventors: Antony Ajan, Iwao Okamoto
  • Patent number: 7056604
    Abstract: A magnetic recording system includes an in-plane magnetic recording medium having a magnetic layer fabricated on a single underlayer or on a plurality of underlayers respectively fabricated on a substrate; a driver unit for driving the in-plane magnetic recording medium in a write direction; a magnetic head having a read unit and a write unit; a unit for moving the magnetic head relative to the in-plane magnetic recording medium; and a read/write signal processing unit for reading an output signal from the magnetic head and writing an input signal to the magnetic recording media, wherein the read unit of the magnetic head is a magnetoresistive head and the single underlayer or at least one of the plurality of underlayers is made of Co-containing amorphous material or fine crystal material, or is made of alloy material, the alloy material having as the main components at least one element selected from a group consisting of Cr, Mo, V and Ta and containing at least one element selected from a group consisting o
    Type: Grant
    Filed: June 3, 2003
    Date of Patent: June 6, 2006
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Tetsuya Kanbe, Akira Ishikawa, Ichiro Tamai, Yotsuo Yahisa, Yuzuru Hosoe, Kiwamu Tanahashi, Yoshibumi Matsuda, Hiroyuki Kataoka, Toshinori Ono, Shinji Fukaya, Kazuhiro Ura, Naoto Endo, Tomoo Yamamoto