Disk Patents (Class 360/135)
  • Publication number: 20090296278
    Abstract: A perpendicular magnetic recording medium includes a nonmagnetic seed layer, a nonmagnetic intermediate layer provided on the nonmagnetic seed layer, and a perpendicular recording layer provided on the nonmagnetic intermediate layer. The nonmagnetic seed layer includes a first seed layer made of an amorphous material, and a second seed layer provided between the first seed layer and the nonmagnetic intermediate layer and made of a material having a fcc structure. The amorphous material includes at least one element selected from a group consisting of Ta, W, Nb, Mo, Zr and alloys thereof which include at least one of Ta, W, Nb, Mo and Zr as a main component exceeding 50 at. %.
    Type: Application
    Filed: March 12, 2009
    Publication date: December 3, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Ryosaku Inamura, Yuta Toyoda
  • Publication number: 20090296279
    Abstract: A magnetic recording medium including: a substrate; plural information recording members that are formed of a hard magnetic material on the substrate, in each of which magnetization in a direction crossing the substrate is generated and, when the information recording members pass in a predetermined traveling direction in a magnetic field for information recording, the magnetization is directed to a direction corresponding to a direction of the magnetic field and information is recorded; and a high-permeability film that is placed on an edge on a front side of the information recording members in the traveling direction and has a magnetic permeability higher than a magnetic permeability of the information recording members.
    Type: Application
    Filed: March 13, 2009
    Publication date: December 3, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Nobutaka Ihara, Hiroto Takeshita, Yuji Ito
  • Patent number: 7622205
    Abstract: A disk substrate for a perpendicular magnetic recording medium is, disclosed. The substrate exhibits sufficient productivity, serves the function of a soft magnetic backing layer of the perpendicular magnetic recording medium, and scarcely generates noise. A perpendicular magnetic recording medium using such a substrate also is disclosed. The disk substrate comprises at least a soft magnetic underlayer formed on a nonmagnetic base plate by means of an electroless plating method. The thermal expansion coefficient of the soft magnetic underlayer is larger than a thermal expansion coefficient of the nonmagnetic disk-shaped base plate. A saturation magnetostriction constant ?s satisfies a relation ?s??1×10?5.
    Type: Grant
    Filed: April 12, 2005
    Date of Patent: November 24, 2009
    Assignee: Fuji Electric Device Technology Co. Ltd.
    Inventors: Hiroyuki Uwazumi, Youichi Tei, Kengo Kainuma, Kazuhito Higuchi, Akira Iso, Hajime Kurihara
  • Publication number: 20090284859
    Abstract: A data storage device, such as a disk drive unit, includes at least one disk for storing data therein. The disk is divided into a plurality of tracks. The disk has at least a first set of tracks that each have stored therein at least one repeatable runout correction code for at least one area of the track, and a second set of tracks that each do not have stored therein any repeatable runout correction codes.
    Type: Application
    Filed: May 1, 2009
    Publication date: November 19, 2009
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Da-woon CHUNG, Dong-wook LEE
  • 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
  • Patent number: 7616404
    Abstract: The magnetic recording medium includes a substrate and a recording layer formed in a predetermined concavo-convex pattern over the substrate, and the recording layer includes recording elements each formed as a convex portion of the recording layer. Surface steps are formed in an inner area including a radially innermost portion of a recording area. Each surface step is formed in such a manner that a portion over a concave portion between the recording elements is recessed toward a substrate to a level below a portion over the recording element. The surface steps are formed such that the recording area can be sectioned into an annular area adjoining the inner area and the inner area where height of the surface steps is larger than that in the annular area.
    Type: Grant
    Filed: December 20, 2007
    Date of Patent: November 10, 2009
    Assignee: TDK Corporation
    Inventors: Takahiro Suwa, Kazuya Shimakawa
  • Publication number: 20090268338
    Abstract: A hard disk drive includes a magnetic head, at least one disk and a controller. A location signal is recorded on the at least one disk for determining a location of the magnetic head in relation to the at least one disk. The controller controls the location of the magnetic head based on the location signal decoded through the magnetic head. At least one of frequency and amplitude of the location signal is variable.
    Type: Application
    Filed: April 24, 2009
    Publication date: October 29, 2009
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Kum-Jung Song, Sang Hoon Chu
  • Publication number: 20090257148
    Abstract: There is provided a magnetic recording medium which contains a substrate in the shape of a disk, and a plural of recording bit formed on the substrate, wherein a bottom face of the recording bit is disposed so as to face the substrate, a top face of the recording bit is disposed so as to correspond to the bottom face of the recording bit, and Twb is larger than Twt, where Twb indicates a width of the bottom face with respect to a radius direction of the magnetic recording medium, and Twt indicates a width of the top face with respect to the radius direction.
    Type: Application
    Filed: December 17, 2008
    Publication date: October 15, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Nobutaka Ihara, Hiroto Takeshita
  • Patent number: 7597792
    Abstract: A method and apparatus is described for gradually transitioning a slider from operation over a patterned data zone to landing on a patterned CSS zone. The ratio of raised area width to recessed area width of a pattern in a transition zone and/or CSS zone may be varied across the radial dimension of the disk. By changing the ratio of raised area width to recessed area width of the pattern in the transition from slider operation over the data zone to landing in the CSS zone, it is possible to gradually change the height of the slider from flying to non-flying conditions.
    Type: Grant
    Filed: September 14, 2005
    Date of Patent: October 6, 2009
    Assignee: WD Media, Inc.
    Inventors: Andrew M. Homola, Judy Lin
  • Publication number: 20090244777
    Abstract: A disclosed method for manufacturing a magnetic recording medium includes a first step of forming a magnetic recording film on a non-magnetic substrate and a second step of forming, in the magnetic recording film, a magnetic recording region which is magnetically recordable and an isolation region which is magnetically non-recordable and includes a first isolation-region portion and a second isolation-region portion. The second step includes the sub-steps of performing first ion implantation on the magnetic recording film to form the first isolation-region portion along a boundary of the isolation region to be formed with the magnetic recording region to be formed; and performing second ion implantation on the magnetic recording film to form the second isolation-region portion in the surface of the isolation region to be formed.
    Type: Application
    Filed: October 22, 2008
    Publication date: October 1, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Sanae Shimizu, Yuji Ito
  • Publication number: 20090244785
    Abstract: A magnetic recording medium suppresses effectively side erasure even when recording dot intervals are reduced. Magnetic dots and a soft magnetic layer are provided on a soft magnetic underlayer with a nonmagnetic layer intervening, so that magnetic dots are separated by the soft magnetic layer, and consequently leakage flux during recording to magnetic dots is absorbed by the soft magnetic layer, side erasure can be suppressed, and moreover the soft magnetic underlayer and soft magnetic layer are separated, so that an influence on recording/reproduction characteristics can be prevented.
    Type: Application
    Filed: December 30, 2008
    Publication date: October 1, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Hideyuki Kikuchi, Kenji Sato, Takuya Uzumaki
  • Publication number: 20090244775
    Abstract: Methods and systems are shown that specify using group counters and track counters to reduce the need for adjacent-track-erasure (ATE) refresh. A group threshold may be used to monitor the number of write operations to a group. The group threshold may be used to determine when it is necessary to monitor the write operations to the tracks in a group on an individual basis.
    Type: Application
    Filed: March 31, 2008
    Publication date: October 1, 2009
    Applicant: Kabushiki Kaisha Toshiba 1-1
    Inventor: Richard M. Ehrlich
  • Publication number: 20090244776
    Abstract: To provide a magnetic transfer master carrier including a base material, a concavo-convex pattern formed by arranging a plurality of convex portions on a surface of the base material, and a magnetic layer provided at least on upper surfaces of the convex portions, wherein the magnetic layer is formed by an ion gun deposition method in which a target material is irradiated with an ion beam and a layer is deposited with sputter particles sputtered from the target material.
    Type: Application
    Filed: March 30, 2009
    Publication date: October 1, 2009
    Applicant: FUJIFILM CORPORATION
    Inventors: Hideyuki KUBOTA, Makoto Nagao
  • Publication number: 20090237829
    Abstract: An information recording medium has a substrate, first recording dots, and second recording dots. The first recording dots are arranged in an array circumferentially in accordance with a predetermined regulation at mutual intervals in accordance with the regulation at a position in accordance with the regulation, and are used to magnetically record information. The second recording dots are arranged in an array circumferentially in accordance with the regulation at mutual intervals in accordance with the regulation. In the second recording dots, plural kinds of positions having different deviation amounts from the position in accordance with the regulation appear in one round of the array. The second recording dots are also used to magnetically record information.
    Type: Application
    Filed: November 21, 2008
    Publication date: September 24, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Yasuyuki Ozawa, Haruhiko Izumi
  • Publication number: 20090231746
    Abstract: In the magnetic recording apparatus, a recording layer is formed in a concavo-convex pattern, and recording elements are formed of convex portions of the concavo-convex pattern. Furthermore, the following equation (I) BL?ERL?BL+2×GL ??(Equation (I)) is satisfied in each of tracks, where BL represents a length of the recording element in a circumferential direction, GL represents a length of a gap between the recording elements in the circumferential direction, and ERL represents an effective recording length which is a length of an effective recording area ER in the circumferential direction, the effective recording area ER being created on a magnetic recording medium by a heating head and a recording head.
    Type: Application
    Filed: February 27, 2009
    Publication date: September 17, 2009
    Applicant: TDK CORPORATION
    Inventors: Akimasa Kaizu, Satoshi Tomikawa, Yoshikazu Soeno
  • Publication number: 20090225634
    Abstract: Method for the bidirectional transmission of data between one or more textile machines (1) producing cross-wound bobbins and/or one or more same-level and/or higher level control systems with a device (2) for transmitting data to a transport medium, which is used for the transporting of data located on the transport medium, the transport medium being in operative connection with the textile machine (1) producing cross-wound bobbins to transmit data via the device (2). According to the invention, a a memory, a hard disc, a magnetic tape, a writable contact disc (CD), a writable digital versatile disc (DVD), a magneto-optical disc (MO disc), a minidisc (MD) or a digital memory card provided in a mobile telephone or a palm-top computer (personal digital assistant) are used as the transporting medium and the device (2) is integrated in an exchangeable manner in the textile machine (1).
    Type: Application
    Filed: September 30, 2006
    Publication date: September 10, 2009
    Applicant: Oerlikon Textile GmbH & Co. KGö
    Inventor: Olav Birlem
  • Publication number: 20090225473
    Abstract: A magnetic recording medium includes a plurality of recording tracks magnetically continuous with respect to a recording direction and arranged intermittently in a track width direction, a plurality of recording dots intermittently formed in the recording tracks in the recording direction and a plurality of space dots alternately formed in the recording track with the recording dots in the recording direction and having a magnetic moment per unit area smaller than a magnetic moment per unit area of the recording dots.
    Type: Application
    Filed: March 3, 2009
    Publication date: September 10, 2009
    Applicant: FUJITSU LIMITED
    Inventor: Hiroto TAKESHITA
  • Patent number: 7582368
    Abstract: A perpendicular magnetic recording system and medium has a multilayered recording layer that includes an exchange-spring structure and a ferromagnetic lateral coupling layer (LCL). The exchange-spring structure is made up of two ferromagnetically exchange-coupled magnetic layers (MAG1 and MAG2), each with perpendicular magnetic anisotropy. MAG1 and MAG2 are either in direct contact with one another or have a coupling layer (CL) located between them. The LCL is located in direct contact with MAG2 and mediates intergranular exchange coupling in MAG2. The ferromagnetic alloy in the LCL has significantly greater intergranular exchange coupling than the ferromagnetic alloy in MAG2, which typically will include segregants such as oxides. The LCL is preferably free of oxides or other segregants, which would tend to reduce intergranular exchange coupling in the LCL.
    Type: Grant
    Filed: September 14, 2006
    Date of Patent: September 1, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Andreas Klaus Berger, Hoa Van Do, Byron Hassberg Lengsfield, III, Natacha F. Supper
  • Publication number: 20090213497
    Abstract: Embodiments of the present invention provide recording area separated magnetic recording media (DTMs, BPMs) allowing magnetic heads to fly lower. According to one embodiment, the recording area separated magnetic recording media are configured so that magnetic recording layers have parts with the relatively higher element ratio of a ferromagnetic material, and parts with the lower element ratio of the ferromagnetic material, occurring periodically in the in-plane direction, and the average height from the substrate surface of the parts with the relatively higher element ratio of a ferromagnetic material is higher than the average height from the substrate surface of the parts with the lower element ratio of the ferromagnetic material.
    Type: Application
    Filed: February 20, 2009
    Publication date: August 27, 2009
    Inventors: Toshinori Ono, Hiroshi Kanai, Tatsuysa Hinoue, Hiroyuki Suzuki, Hiroshi Inaba
  • Patent number: 7580223
    Abstract: According to one embodiment, a magnetic recording media includes a substrate having recording tracks and separating regions separating the recording tracks, the separating regions having patterns of protrusions and recesses formed therein, and a recording film deposited on the substrate, in which a difference in height between a top of the recording track and a top of the separating region is 2 nm or more and 7 nm or less, and a difference in height between the top of the recording track and a bottom of the separating region is 10 nm or more.
    Type: Grant
    Filed: June 28, 2006
    Date of Patent: August 25, 2009
    Assignees: Kabushiki Kaisha Toshiba, Showa Denko K.K.
    Inventors: Masatoshi Sakurai, Akira Kikitsu, Masahiro Oka
  • Publication number: 20090207523
    Abstract: A magnetic recording medium formed on a substrate. The magnetic recording medium includes a data region including a plurality of magnetic dots arranged at predetermined positions on the substrate, for recording information; and a servo region for specifying the positions of the magnetic dots, the servo region including a plurality of magnetic segments arranged at predetermined positions on the substrate, each of the magnetic segments being smaller than each of the magnetic dots.
    Type: Application
    Filed: February 2, 2009
    Publication date: August 20, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Takayuki Kawabe, Haruhiko Izumi, Yasuyuki Ozawa, Takuya Kamimura
  • Patent number: 7572528
    Abstract: A magnetic recording medium is obtained by easily patterning a magnetic recording layer without deteriorating its electromagnetic conversion characteristics, by forming a silicon-based protective film between the magnetic recording layer and a photoresist, and performing dry etching and oxygen plasma processing.
    Type: Grant
    Filed: May 24, 2005
    Date of Patent: August 11, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takayuki Yamamoto, Masatoshi Sakurai, Yoshiyuki Kamata
  • Publication number: 20090195925
    Abstract: According to one embodiment, a patterned magnetic recording media has a magnetic recording layer and a protective layer formed on a substrate, in which the magnetic recording layer including a magnetic material patterned in tracks and a nonmagnetic material filled in between the tracks in a data area, and has a recessed portion formed in an area within 1 mm from an outer media end and extending to the media end. The recessed portion being formed 1 to 50 nm deeper than the data area.
    Type: Application
    Filed: April 6, 2009
    Publication date: August 6, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Akira Kikitsu, Yoshiyuki Kamata, Takayuki Yamamoto, Hiroyuki Hyodo
  • Publication number: 20090195929
    Abstract: According to one embodiment, a method of manufacturing a discrete track recording medium includes forming protruded magnetic patterns on a substrate, and repeating processes of depositing a nonmagnetic material so as to be filled in recesses between the magnetic patterns and etching back the nonmagnetic material two or more times with rotating the substrate in a plane thereof by an angle less than one revolution.
    Type: Application
    Filed: March 9, 2009
    Publication date: August 6, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshiyuki Kamata, Satoshi Shirotori, Kaori Kimura, Masatoshi Sakurai
  • Publication number: 20090195928
    Abstract: A magnetic disk apparatus includes a non-volatile memory for saving read data and write data transmitted from a host. The magnetic disk apparatus includes a non-volatile memory that saves read data and write data transmitted from a host. The non-volatile memory has a host designated data area that saves host designated data designated by the host, and an independent data area that independently saves data other than the host designated data wherein the independent data area comprises a read data area that saves read data based on a read request command transmitted from the host and a write data area that saves write data based on a write request command.
    Type: Application
    Filed: November 7, 2008
    Publication date: August 6, 2009
    Applicant: FUJITSU LIMITED
    Inventor: Takehiro Ogawa
  • Publication number: 20090185308
    Abstract: On a magnetic recording medium, M sets of burst patterns are formed along a direction of rotation of a substrate in each burst pattern region, where M is a natural number of two or higher. Each burst pattern is formed so as to include two types of burst signal units that are positioned at different distances from a center of data track patterns and have an equal length along a radial direction of the substrate. The length along the radial direction is (2·M/N) times the track pitch, where N is a natural number of two or higher.
    Type: Application
    Filed: March 27, 2009
    Publication date: July 23, 2009
    Applicant: TDK CORPORATION
    Inventors: Akimasa KAIZU, Yoshikazu SOENO, Makoto MORIYA
  • Publication number: 20090180213
    Abstract: A discrete track-type magnetic recording medium (30) includes a nonmagnetic substrate (1), a magnetic recording track and a servo signal pattern that are provided on at least one side of the nonmagnetic substrate and a part (4) nonmagnetized through implantation (7) of ions from above a mask (6) having a shape of a pattern expected to be separated for physically separating the magnetic recording track and the servo signal pattern. A magnetic recording and reproducing device includes the magnetic recording medium (30), a driving part (26) serving to drive the magnetic recording medium in a direction of recording, a magnetic head (27) composed of a recording part and a reproducing part, means (28) to impart motion to the magnetic head relative to the magnetic recording medium and recording and reproducing signal processing means (29) for entering a signal into the magnetic head and reproducing an output signal from the magnetic head.
    Type: Application
    Filed: February 19, 2007
    Publication date: July 16, 2009
    Applicant: SHOWA DENKO K.K.
    Inventors: Masato Fukushima, Akira Sakawaki, Yasumasa Sasaki
  • Patent number: 7562374
    Abstract: Provided is a form factor disk such as an optical or magnetic disk used in electronic appliances and information appliances. The form factor disk includes: a circular plate having a first hole for inserting a rotational shaft, a plurality of second holes formed adjacent to the first hole, and an information storage region formed at a surface thereof; an upper metal hub located on the circular plate, and having a hole aligned with the first hole of the circular plate and column-shaped joints formed at portions corresponding to the second holes of the circular plate; and a lower metal hub located under the circular plate, and having a hole aligned with the first hole of the circular plate and column-shaped joints formed at portions corresponding to the second holes of the circular plate, wherein the joints of the upper and lower metal hubs are jointed through the second holes.
    Type: Grant
    Filed: June 9, 2005
    Date of Patent: July 14, 2009
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Woo Seok Cheong, Yong Goo Yoo, Sung Q Lee, Ho Jun Ryu, Mun Cheol Paek, Eun Kyoung Kim
  • Publication number: 20090168244
    Abstract: The magnetic recording medium includes: a substrate; a recording layer formed in a predetermined concavo-convex pattern over the substrate, the concavo-convex pattern including a convex portion that serves as a recording element; and a filling portion that fills a concave portion between the recording elements. The filling portion comprises a metal-based main filling material and nitrogen. Nitrogen is unevenly distributed in the filling portion such that the ratio of the number of nitrogen atoms to the total number of atoms of the main filling material and nitrogen atoms is greater in the upper surface portion of the filling portion than in the lower portion thereof.
    Type: Application
    Filed: December 19, 2008
    Publication date: July 2, 2009
    Applicant: TDK CORPORATION
    Inventors: Shuichi Okawa, Kazuhiro Hattori, Narutoshi Fukuzawa, Takahiro Suwa
  • Publication number: 20090168245
    Abstract: Data track patterns and servo patterns are formed on an information recording medium by concave/convex patterns divided into ring-shaped regions that are concentric with the data track patterns. In the servo patterns, a unit convex length and a unit concave length along the direction of rotation increase in each ring-shaped region from an inside to an outside of the ring-shaped region in proportion to the distance from the center of the data track patterns and a value produced by dividing an average unit convex (or concave) length inside each ring-shaped region by a distance from the center to the ring-shaped region decreases toward the outer periphery of the medium. The ring-shaped regions include plural first regions between an innermost region and an outermost region. Respective lengths along a radial direction of the first regions increase toward an outer periphery of the medium.
    Type: Application
    Filed: December 23, 2008
    Publication date: July 2, 2009
    Applicant: TDK CORPORATION
    Inventors: Yoshikazu Soeno, Kazuya Shimakawa
  • Patent number: 7554768
    Abstract: On an information recording medium, a data track pattern and a servo pattern composed of a concave/convex pattern including a plurality of convex parts are formed on at least one surface of a substrate and respective concave parts in the concave/convex pattern are filled with non-magnetic material. In the concave/convex pattern that constructs the data track pattern, the respective convex parts are formed concentrically or in a spiral. In the concave/convex pattern that constructs the servo pattern, a unit convex part length along a direction of rotation of the substrate is set so that a value produced by dividing the unit convex part length by a distance from a center of the data track pattern decreases from an inner periphery to an outer periphery.
    Type: Grant
    Filed: August 31, 2005
    Date of Patent: June 30, 2009
    Assignee: TDK Corporation
    Inventors: Yoshikazu Soeno, Takahiro Suwa
  • Publication number: 20090161254
    Abstract: A magnetic recording medium for use in digital magnetic recording, which comprises a nonmagnetic substrate having deposited thereon a magnetic layer, wherein with respect to the in-plane direction, the magnetic recording layer comprises a plurality of ferromagnetic regions separated from each other by an antiferromagnetic region. A production method of the magnetic recording medium and a magnetic disc apparatus are also disclosed.
    Type: Application
    Filed: September 8, 2008
    Publication date: June 25, 2009
    Applicants: FUJITSU LIMITED, NATIONAL UNIVERSITY CORPORATION AKITA UNIVERSITY
    Inventors: Shunji Ishio, Hitoshi Saito, Takashi Hasegawa, Iwao Okamoto, Naoya Yamamoto
  • Publication number: 20090163079
    Abstract: In various embodiments, applicant's teachings are related to an apparatus and method of providing a data storage device to be interfaced between a data receiving apparatus in a data collecting configuration and a data processor in a data retrieval configuration. In various embodiments, applicant's teachings are related to an apparatus and method of selectively operating a data storage device to receive data from a data receiving apparatus. In some embodiments, the data storage device receives data when an acceptable operating condition of the device is sensed. In various embodiments, applicant's teachings are related to an apparatus and method to reduce the time that the data storage device is in operation while it is collecting the data.
    Type: Application
    Filed: September 25, 2006
    Publication date: June 25, 2009
    Inventor: Quang V.T. Nguyen
  • Patent number: 7550210
    Abstract: A perpendicular magnetic recording medium has an “exchange-spring” type magnetic recording layer (RL) formed of two ferromagnetic layers with substantially similar anisotropy fields that are ferromagnetically exchange-coupled by a nonmagnetic or weakly ferromagnetic coupling layer. Because the write head produces a larger magnetic field and larger field gradient at the upper portion of the RL, while the field strength decreases further inside the RL, the upper ferromagnetic layer can have a high anisotropy field. The high field and field gradient near the top of the RL, where the upper ferromagnetic layer is located, reverses the magnetization of the upper ferromagnetic layer, which then assists in the magnetization reversal of the lower ferromagnetic layer. Because both ferromagnetic layers in this exchange-spring type RL have a high anisotropy field, the thermal stability of the medium is not compromised. The medium shows improved writability, i.e.
    Type: Grant
    Filed: March 9, 2006
    Date of Patent: June 23, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Andreas Klaus Berger, Hoa Van Do, Eric E. Fullerton, Yoshihiro Ikeda, Byron Hassberg Lengsfield, III, Natacha F. Supper
  • Patent number: 7549209
    Abstract: A method of forming a discrete track recording pattern in a magnetic recording disk. In one embodiment, the discrete track recording pattern may be formed in a NiP layer continuous throughout the discrete track recording pattern. Alternatively, the discrete track recording pattern may be formed in a substrate.
    Type: Grant
    Filed: January 21, 2005
    Date of Patent: June 23, 2009
    Assignee: WD Media, Inc.
    Inventors: David E. Wachenschwanz, Gerardo A. Bertero, David Treves, Andrew Homola, James L. Chao, Christopher H. Bajorek
  • Publication number: 20090153999
    Abstract: A hard disk includes: a plurality of servo areas which are elongated radially from a center of the hard disk to an outward thereof over tracks thereof; and a plurality of data areas which are respectively provided between the plurality of servo areas; wherein alternative operation is conducted per servo sector containing one of the plurality of servo areas and a data area provided subsequent to the one of the plurality of servo areas and having a defect created therein when a user sector containing at least a portion of the data area and functioning as an access unit has the defect therein.
    Type: Application
    Filed: June 30, 2008
    Publication date: June 18, 2009
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Kenji Yoshida, Yuuichi Abe
  • 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: 7548398
    Abstract: A thermally assisted magnetic recording medium includes a substrate having a first surface and a second surface opposite to the first surface. A recording layer is formed on the first surface of the substrate. A plurality of thermally conductive regions are provided at the first surface of the substrate to extend in parallel to each other and about the center of rotation of the recording medium. The thermally conductive regions have a higher thermal conductivity than the substrate, and are at least partially embedded in the substrate.
    Type: Grant
    Filed: February 15, 2006
    Date of Patent: June 16, 2009
    Assignee: Fujitsu Limited
    Inventors: Takuya Kamimura, Koji Matsumoto, Yuzuru Yamakage, Koichi Iida
  • Publication number: 20090147403
    Abstract: Embodiments in accordance with the present invention provide a perpendicular magnetic recording medium where the signal to noise (S/N) of the media is improved. In a particular embodiment, a magnetic layer is applied to the recording magnetic layer of the recording medium in which the normalization crystal grain cluster size (Dn) is controlled so as to satisfy 1?Dn?1.9, where the mean value of the recording crystal grain cluster area obtained by summation of the area of neighboring grains having the same crystal orientation in both the a-axis and the c-axis of the recording layer crystal grain of the magnetic layer is normalized by the mean grain size.
    Type: Application
    Filed: November 18, 2008
    Publication date: June 11, 2009
    Inventors: Ryoko Araki, Yoshio Takahashi
  • 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
  • Publication number: 20090141399
    Abstract: A magnetic-recording medium which is provided on a nonmagnetic substrate with at least an orientation-controlling layer for controlling the orientation of a layer formed directly thereon, a perpendicularly magnetic layer having an easily magnetizing axis oriented mainly perpendicularly relative to the nonmagnetic substrate, and a protective layer. The perpendicularly magnetic layer includes two or more magnetic layers, at least one of the magnetic layers is a layer having Co as a main component and containing Pt as well and containing an oxide, and at least another of the magnetic layers is a layer having Co as a main component and containing Cr as well and containing no oxide.
    Type: Application
    Filed: November 20, 2008
    Publication date: June 4, 2009
    Applicants: SHOWA DENKO K.K., KABUSHIKI KAISHA TOSHIBA
    Inventors: Akira SAKAWAKI, Kenji Shimizu, Kazuo Kobayashi, Hiroshi Sakai, Soichi Oikawa, Takeshi Iwasaki, Tomoyuki Maeda, Futoshi Nakamura
  • Patent number: 7542235
    Abstract: A perpendicular magnetic recording medium having a soft magnetic backing layer in which amount of cobalt elution is suppressed without imposing restraint on the construction of the protective layer is disclosed. The perpendicular magnetic recording medium of the invention comprises at least a soft magnetic backing layer, a magnetic recording layer, and a protective layer sequentially laminated on a nonmagnetic substrate, the soft magnetic backing layer containing iron and cobalt, and further containing at least two elements selected from Si, Ni, Ta, Nb, Zr, Ti, Cr, Mo, and B, and the surface roughness of the soft magnetic backing layer being in a range of 0.2 nm to 0.8 nm in center line average roughness. The iron concentration in the soft magnetic backing layer preferably is in the range of 40 at % to 85 at %, the cobalt concentration preferably is in a range of 10 at % to 45 at %, and the total concentration of Si, Ni, Ta, Nb, Zr, Ti, Cr, Mo, and B is in a range of 20 at % to 50 at %.
    Type: Grant
    Filed: March 7, 2006
    Date of Patent: June 2, 2009
    Assignee: Fuji Electric Device Technology Co., Ltd.
    Inventor: Yoshiyuki Kuboki
  • Publication number: 20090135518
    Abstract: A magnetic recording medium with domain wall pinning sites including a substrate, a soft magnetic underlayer, and a magnetic recording layer overlying the soft magnetic underlayer. In one embodiment the magnetic recording layer has at least two grooves providing a track having first and second sidewalls formed by the grooves. The sidewalls provide a plurality of pinning sites formed between the sidewalls for pinning magnetic domain walls in the track. At least one of the pinning sites includes a first indentation in the first sidewall and a paired second indentation in the second sidewall. In one embodiment data can be stored within the magnetic recording layer by positioning a write head adjacent the track and inducing at least two magnetic domains defining a domain wall. The domain wall migrates to one of the pinning sites in the track.
    Type: Application
    Filed: November 28, 2007
    Publication date: May 28, 2009
    Inventors: Dieter Weller, Timothy J. Klemmer, Kim Y. Lee
  • Publication number: 20090135519
    Abstract: A magnetic recording medium includes a disk substrate, and recording cells arrayed on the disk substrate in a track direction, the recording cells includes a ferromagnetic pattern and a magnetic pattern formed on one of two sidewalls of the ferromagnetic pattern in the track direction and having a lower crystalline magnetic anisotropy constant Ku than that of the ferromagnetic pattern.
    Type: Application
    Filed: November 20, 2008
    Publication date: May 28, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hiroyuki Hieda, Kazuto Kashiwagi, Akira Kikitsu, Yousuke Isowaki, Yoshiyuki Kamata
  • Publication number: 20090128957
    Abstract: A connecting apparatus adapted in a conjunctive structure is provided. The conjunctive structure comprises a baseboard, a peripheral element and a connecting apparatus. The connecting apparatus comprises at least one first connecting element and at least one second connecting element. The first connecting element is a magnetic element and is placed on one corner of the peripheral element. The second connecting element is placed around a hole of the baseboard, and the second connecting element comprises two adjacent magnetic elements with opposite polarity arrangement.
    Type: Application
    Filed: February 26, 2008
    Publication date: May 21, 2009
    Applicant: Quanta Computer Inc.
    Inventor: Chun-Wang Lin
  • Publication number: 20090128958
    Abstract: A magnetic transfer master substrate for transferring magnetic information thereof to a perpendicular recording magnetic recording medium in contact therewith under application of a magnetic field comprises a transfer surface area with a magnetic layer formed thereon in a pattern according to the magnetic information to be transferred to the perpendicular magnetic recording medium and a non-transfer surface area laying below said transfer surface area, wherein the magnetic layer has a perpendicular magnetic anisotropy of an anisotropy energy higher than 4×106 erg/cm3.
    Type: Application
    Filed: November 21, 2008
    Publication date: May 21, 2009
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Yoichi NISHIDA, Masakazu Nishikawa, Hideyuki Kubota, Ryuji Sugita, Takashi Komine
  • Publication number: 20090122447
    Abstract: A disk drive includes a magnetic recording medium rotatably supported, a spindle motor for spinning the recording medium, a slider having a head, a supporting arm having the slider at a first end facing the recording medium, a bearing for holding the supporting arm rotatably along a recording surface of the medium and pivotably in a vertical direction with respect to the recording surface, a leaf spring giving thrusting force to a first end of the supporting arm toward the medium, and a driver for rotating the supporting arm along the recording surface. When the driver rotates the supporting arm along the recording surface and parks the head in a given evacuation area on the recording surface, a second end of the supporting arm is depressed.
    Type: Application
    Filed: September 16, 2005
    Publication date: May 14, 2009
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventor: Hideki KUWAJIMA
  • Publication number: 20090123870
    Abstract: An electron beam lithographic method and system for forming a micro-pattern, including servo patterns each of which comprises a plurality of recessed servo elements in a track and groove patterns each of which comprises an inter-track groove extending along the track and to be formed on a discrete track medium, on the a resist coated disc substrate by scanning the resist-coated surface with an electron beam during rotation of the disc substrate.
    Type: Application
    Filed: November 13, 2008
    Publication date: May 14, 2009
    Applicant: FUJIFILM CORPORATION
    Inventors: Toshihiro USA, Kazunori Komatsu
  • Publication number: 20090116147
    Abstract: Perpendicular magnetic recording disks and methods of fabricating perpendicular magnetic recording disks are described. The perpendicular magnetic recording disk includes a soft magnetic uniderlayer (SUL) structure, an interlayer, and a perpendicular magnetic recording layer. The SUL structure has an increased permeability from an inner radius of the disk to an outer radius of the disk. As a result, the magnetic write width (MWW) on the tracks of the disk is substantially uniform throughout the disk.
    Type: Application
    Filed: November 5, 2007
    Publication date: May 7, 2009
    Inventor: Gunn Choe
  • Publication number: 20090110962
    Abstract: A perpendicular media is formed without an adhesion layer between the substrate and soft underlayer (SUL) to reduce the cost of fabrication. The thickness of the SUL is reduced to less than 50 nm to increase the film adhesion strength between the substrate and SUL. The perpendicular media comprises only a substrate, the SUL, an exchange break layer, a recording layer, and a protective overcoat.
    Type: Application
    Filed: October 31, 2007
    Publication date: April 30, 2009
    Applicant: Hitachi Global Storage Technologies Netherlands BV
    Inventors: Hong Deng, Yoshihiro Ikeda