Disk Patents (Class 360/135)
  • Publication number: 20080259482
    Abstract: A magnetic media that has at least one groove. The groove is created by a process that includes initially forming a temporary layer over a magnetic layer of the disk. One or more grooves are formed in the temporary and magnetic layers. The temporary layer is removed and a protective layer is formed over the magnetic layer and within the groove.
    Type: Application
    Filed: April 20, 2007
    Publication date: October 23, 2008
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Kiseok Moon, Soo Youl Hong, Yawshing Tang, Xiaodong Che
  • Patent number: 7440233
    Abstract: The present invention provides a magnetic recording medium with a reduced tendency for a free layer to become thicker near an outer periphery than near an inner periphery of a recording zone as well as provides an information reproducing apparatus which is equipped with the magnetic recording medium and reproduces information according to the magnetization at various points on the magnetic recording medium. A magnetic layer carries information in an outer zone outside a predetermined inner zone around a through-hole. That part of the free layer which is located in the outer zone is thinner near the outer periphery than near the inner periphery.
    Type: Grant
    Filed: February 14, 2005
    Date of Patent: October 21, 2008
    Assignee: Fujitsu Limitd
    Inventor: Shinichi Takahashi
  • Publication number: 20080239534
    Abstract: Watermarks for patterned magnetic media. The watermarks are used to demonstrate the unauthorized replication of a patterned magnetic media. The watermarks include a dibit, a pattern in an open region, shifting of data, shifting of a sync mark and large length scale perturbations. Also described are methods to determine if a watermark appears on a patterned media.
    Type: Application
    Filed: March 30, 2007
    Publication date: October 2, 2008
    Inventors: Thomas Robert Albrecht, Zvonimir Z. Bandic, Jorge Campello de Souza
  • Publication number: 20080239570
    Abstract: A spindle motor can suppress the generation of noise during swinging and the extend service life, and also suppress the increase in current consumption. The outside diameter Do of a thrust hydrodynamic groove 3 is at least 10% of the outside diameter Dd of a disk-shaped medium 20, and the depth of the radial hydrodynamic groove is greater than the depth of the thrust hydrodynamic groove. By adjusting to specific numbers, the angular stiffness in the thrust bearing is raised, and even if a disturbance torque should be applied, wear or noise caused by metal contact inside the bearing can be suppressed.
    Type: Application
    Filed: March 24, 2008
    Publication date: October 2, 2008
    Inventors: Masafumi KUMOI, Yukinori MARUYAMA
  • Publication number: 20080239548
    Abstract: A disk drive includes a disk for storing information representing data, and a memory device. A method for writing includes locating a first data sector on a disk where a write operation fails, identifying the first data sector and a plurality of other data sectors near the first data sector as a grown defect, and storing the location of the first data sector and the plurality of other data sectors on a grown defect list. The memory device includes a list of grown defects that identifies a plurality of data sectors stored along a track between the first servo wedge and the second servo wedge on a selected track as data sectors which may not be written to.
    Type: Application
    Filed: March 30, 2007
    Publication date: October 2, 2008
    Applicant: TOSHIBA AMERICA INFORMATION SYSTEMS, INC.
    Inventors: Stephen G. Paul, Dar-Der Chang
  • Publication number: 20080239555
    Abstract: A method for servo correction includes determining a first wedge offset reduction field value for a read element from information in a servo burst area of a wedge on a disk, storing the first wedge offset reduction field value, determining a second wedge offset reduction field value for the read element from information in the servo burst area of the wedge on the disk, storing the second wedge offset reduction field value, and estimating an offset value of the read element from a desired track on the disk using at least one of the first wedge offset reduction value or second wedge offset reduction field value.
    Type: Application
    Filed: March 30, 2007
    Publication date: October 2, 2008
    Applicant: TOSHIBA AMERICA INFORMATION SYSTEMS, INC.
    Inventors: Richard M. Ehrlich, Thorsten Schmidt
  • Patent number: 7423841
    Abstract: A magnetic recording medium capable of preventing contact with a magnetic head for use in recording or reproduction, during recording or reproducing of record data. The magnetic recording medium has a disk-shaped substrate having a surface formed with an annular data-recording area, an outer area outward of the data-recording area, and an inner area inward of the same. The annular data-recording area has a plurality of tracks separated from each other by concentric separating grooves. At least one of the outer area and the inner is subjected to lift-adjusting treatment for enabling adjustment of lifts applied to the magnetic head. This makes it possible to effectively prevent the magnetic head from being inclined to be brought into contact with the magnetic recording medium.
    Type: Grant
    Filed: July 15, 2004
    Date of Patent: September 9, 2008
    Assignee: TDK Corporation
    Inventors: Mitsuru Takai, Kazuhiro Hattori
  • Patent number: 7423842
    Abstract: A magnetic recording medium including at least a disk substrate 1A, a magnetic recording layer 5 formed with a predetermined concavo-convex pattern on the disk substrate 1A, and a non-magnetic layer 6 filled into concave portions of the concavo-convex pattern, so as to have data track regions 20 and servo pattern regions 21. Due to the existence of concaves and convexes in the surface of each data track region 20, the foregoing problem is solved. On this occasion, arithmetical mean deviation of the assessed profile Ra of the surface of each data track region 20 is preferably not lower than 0.3 nm. The difference in surface level between each concave and each convex existing in the surface of the data track region 20 is preferably not larger than 6 nm.
    Type: Grant
    Filed: February 22, 2005
    Date of Patent: September 9, 2008
    Assignee: TDK Corporation
    Inventors: Minoru Fujita, Mitsuru Takai, Kazuya Shimakawa
  • Publication number: 20080212233
    Abstract: A method of manufacturing a storage medium apparatus having a storage medium that stores data. The method includes disposing the storage medium onto a first unit having an insertion section to be inserted into a through hole of the storage medium and an abutment face made of a soft-metal material and spreading around the insertion section, such that the abutment face abuts a surface of the storage medium. The method further includes: abutting an abutment face of a second unit, made of a soft-metal material, on a surface of the storage medium opposite to the surface abutting the abutment face of the first unit; and while holding the storage medium between the first unit and the second unit, fixing the storage medium and at least one of the first unit and the second unit by rotating the storage medium and the one relatively to each other about the through hole.
    Type: Application
    Filed: January 4, 2008
    Publication date: September 4, 2008
    Applicant: Fujitsu Limited
    Inventor: Yoshiyuki Nanba
  • Publication number: 20080212231
    Abstract: The magnetic recording medium includes a substrate and a recording layer formed in a predetermined concavo-convex pattern over the substrate, the recording layer including recording elements each formed as a convex portion of the recording layer. Surface steps are formed in an outer area including a radially outermost 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 the 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 outer area and the outer area where height of the surface steps is larger than that in the annular area.
    Type: Application
    Filed: January 3, 2008
    Publication date: September 4, 2008
    Applicant: TDK CORPORATION
    Inventors: Takahiro Suwa, Kazuya Shimakawa
  • Patent number: 7419730
    Abstract: An antiferromagnetically coupled (AFC) magnetic recording medium with an AFC master layer comprising at least two magnetic layers with the top magnetic layer including copper is described. The slave layer is separated from the master layer structure by a nonmagnetic spacer layer selected to antiferromagnetically couple the layers. The master layer structure according to the invention includes a bottom and top layer of distinct ferromagnetic materials. Preferably, the top layer of the master layer is a cobalt alloy including from 1 to 5 at. % copper with an example being CoPt13Cr20B8Cu2. The AFC magnetic layer structure can be used with a variety of substrates including circumferentially textured glass and NiP/AlMg.
    Type: Grant
    Filed: August 31, 2004
    Date of Patent: September 2, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Xiaoping Bian, Mary Frances Doerner, Tetsuya Kanbe, Mark Mercado, Mohammad Mirzamaani, Adam Polcyn, Kai Tang
  • Publication number: 20080204933
    Abstract: A perpendicular magnetic recording medium comprises a layer stack formed over a surface of a non-magnetic substrate, and comprising, in overlying sequence from the surface: a magnetically soft underlayer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material formed thereon; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer on the interlayer structure; wherein the interlayer structure is a triple-layer stacked structure comprising: a first interlayer of a first non-magnetic material proximal the magnetically soft underlayer and containing Ru; a second interlayer of a second non-magnetic material in overlying contact with the first interlayer and not containing Ru; and a third interlayer of a third non-magnetic material in overlying contact with the second interlayer and containing Ru.
    Type: Application
    Filed: February 23, 2007
    Publication date: August 28, 2008
    Inventors: Abebe Hailu, Weilu Xu, Xiaoguang Ma, Chung-Hee Chang, Shoutao Wang, Charles C. Chen
  • Publication number: 20080204934
    Abstract: There is provided a method for fabricating a magnetic recording medium that provides high throughput, low manufacturing cost, and no degradation in accuracy in pattern size in fine pattern formation. A resist layer is formed on a substrate or cutting work layer. The surface of the substrate is divided into two or more areas using the center of rotation of the substrate as a reference point. An optical, contactless pattern transfer method is used to transfer a figure pattern contained in the divided area through a mask to the resist layer so as to form a latent image of the figure pattern. The pattern transfer is similarly carried out for the divided area. After the pattern transfer processes for all the divided areas are completed, the entire resist layer is developed to form a resist pattern. The resist pattern is used as a mask to cut the substrate or cutting work layer. As a result, there is provided the substrate or cut work layer onto which a fine pattern has been transferred.
    Type: Application
    Filed: November 15, 2007
    Publication date: August 28, 2008
    Inventors: Yuko Tsuchiya, Chiseki Haginoya
  • Publication number: 20080204935
    Abstract: It is made possible to fabricate a bit-patterned magnetic recording medium having a high recording density and making favorable address deciphering possible. An original disk fabrication method for irradiating a photosensitive resin film with an electron beam to draw a pattern, the method includes: irradiating the electron beam by using a plurality of blanking signals every rotation of a stage per bit unit, when drawing the pattern in a part corresponding to an address part on a photosensitive resin film.
    Type: Application
    Filed: February 15, 2008
    Publication date: August 28, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Takeshi OKINO
  • Patent number: 7417826
    Abstract: A magnetic recording medium on which servo information is recorded efficiently with a sufficient output amplitude for favorable read accuracy of the servo information. In servo areas, a magnetic layer is separated into a plurality of servo pattern unit parts forming a predetermined servo pattern and servo pattern peripheral parts/part surrounding the servo pattern unit parts. The servo pattern unit parts and the servo pattern peripheral parts/part are formed in different sizes so as to have different magnetic properties.
    Type: Grant
    Filed: March 22, 2004
    Date of Patent: August 26, 2008
    Assignee: TDK Corporation
    Inventors: Kazuhiro Hattori, Shuichi Okawa, Katsuyuki Nakada
  • Patent number: 7409759
    Abstract: Provided is a method and system for manufacturing a hard drive platen. The method includes depositing two or more types of film around a central core to form a plurality of film layers, each film layer being of a different type than its adjacent layers. Next, the deposited film layers are sectioned to expose a patterned surface. The patterned surface is then planarized and selectively etched to expose patterns comprised of one of the types of film to a predetermined depth to produce a selectively etched surface. Magnetic material it deposited within etches of the surface and the surface is then planarized to form separated magnetic tracks therein.
    Type: Grant
    Filed: December 16, 2004
    Date of Patent: August 12, 2008
    Assignee: ASML Holding N.V.
    Inventor: Harry Sewell
  • Publication number: 20080182131
    Abstract: According to one embodiment, a soft magnetic layer, a first nonmagnetic underlayer having a fine crystal structure and made of Pd or a Pd alloy, a second nonmagnetic underlayer made of Ru or an Ru alloy, and a perpendicular magnetic recording layer are stacked on a nonmagnetic substrate.
    Type: Application
    Filed: January 16, 2008
    Publication date: July 31, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Takeshi Iwasaki
  • Publication number: 20080180843
    Abstract: Embodiments of the present invention provide a perpendicular magnetic recording medium having an improved writing property due to the exchange spring effect and capable of stable production. According to one embodiment, a perpendicular magnetic recording medium includes a non-magnetic substrate; an adhesion layer; a soft magnetic underlayer; a seed layer; and intermediate layer; a magnetic recording layer at least including a perpendicular recording layer, a writing assist layer, and a magnetic coupling layer disposed between the perpendicular recording layer and the writing assist layer; a protective layer, and a lubrication layer, in which the saturation magnetization of the magnetic coupling layer is lower than the saturation magnetization of the writing assist layer, the saturation magnetization of the magnetic coupling layer is 300 kA/m (300 emu/cc) or lower, and the thickness of the magnetic coupling layer is 1 nm or more and 3 nm or lower.
    Type: Application
    Filed: January 17, 2008
    Publication date: July 31, 2008
    Inventors: Zhengang Zhang, Ikuko Takekuma, Kiwamu Tanahashi
  • Publication number: 20080180827
    Abstract: A magnetic microstructure comprising (i) a magnetic storage layer having a magnetic easy axis perpendicular to a film plane of the storage magnetic layer; (ii) a magnetic assist layer having a magnetic easy axis in the film plane; and (iii) a phase transition interlayer between the magnetic storage layer and the magnetic assist layer. The phase transition layer comprises a material, such as FeRh, that switches from antiferromagnetic at ambient to ferromagnetic at a transition temperature that is greater than ambient, but below the Curie temperature. When the phase transition interlayer is in antiferromagnetic phase, there exists little magnetic coupling between the storage and assist layers. When the interlayer changes to ferromagnetic phase, the interlayer couples the magnetic moments of the storage and assist layer ferromagnetically.
    Type: Application
    Filed: January 31, 2007
    Publication date: July 31, 2008
    Applicant: Carnegie Mellon University
    Inventors: Jian-Gang Zhu, David E. Laughlin
  • Publication number: 20080180844
    Abstract: A defect inspection is performed for each of glass substrates by a surface defect detector. The distance from the center of the glass substrate to a detected defect, as a radius of a nonmagnetic region to be formed circular, is recorded along with an ID assigned to the glass substrate. Such defect information is recorded in a defect list using a printer or recorded in an RFID tag using an RFID writer. The defect list or the RFID tag is attached to a glass-substrate case. Each glass substrate and its defect information are in one-to-one correspondence and are provided to a customer as a magnetic disk manufacturer. Based on the obtained defect information, the customer manufactures magnetic disks each being a discrete track recording medium having the nonmagnetic region formed at the position where the defect is present.
    Type: Application
    Filed: January 15, 2008
    Publication date: July 31, 2008
    Applicants: HOYA CORPORATION
    Inventors: Hiroshi TAKEDA, Ken-ichi NISHIMORI, Tomotaka YOKOYAMA, Tadashi TOMONAGA
  • Patent number: 7406605
    Abstract: Medium individual information formed an information recording medium is obtained, and a management key used for recording or regeneration on the information recording medium corresponding to the medium individual information is generated, and the predetermined information is encoded to create encode data by using the management key when recording predetermined information, the encode data recorded on the information recording medium is decoded to create decode data by using the transferred management key when regenerating the predetermined information.
    Type: Grant
    Filed: October 22, 2002
    Date of Patent: July 29, 2008
    Assignee: Fuji Electric Device Technology Co., Ltd.
    Inventor: Teruhisa Yokosawa
  • Publication number: 20080174913
    Abstract: A servo pattern magnetization method is provided, having full-amplitude servo signals, to eliminate the need for intensity modification and waveform shaping during servo signal reading, and to improve the precision of head positioning and enable an increase in track recording density. A servo pattern magnetization method for a perpendicular recording discrete track medium, having a plurality of recording areas and a plurality of servo areas separating the plurality of recording areas, has a process of recording magnetization perpendicular to the substrate and in opposite directions in each of the magnetic recording layers of the plurality of servo blocks, by means of the leakage magnetic field from the soft magnetic layers separated from other servo blocks when a magnetic field is applied.
    Type: Application
    Filed: January 10, 2008
    Publication date: July 24, 2008
    Applicant: FUJI ELECTRIC DEVICE TECHNOLOGY CO., LTD.
    Inventor: Kiminori SATO
  • Publication number: 20080174914
    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: Application
    Filed: January 11, 2008
    Publication date: July 24, 2008
    Applicant: TDK CORPORATION
    Inventors: Mitsuru TAKAI, Shuichi OKAWA
  • Patent number: 7403355
    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 servo pattern, a unit convex part length along a direction of rotation of the substrate and a unit concave part length along the direction of rotation are set so that the ratio of the unit convex part length to the unit concave part length decreases from an inner periphery to an outer periphery of the information recording medium.
    Type: Grant
    Filed: August 31, 2005
    Date of Patent: July 22, 2008
    Assignee: TDK Corporation
    Inventors: Yoshikazu Soeno, Takahiro Suwa
  • Patent number: 7403353
    Abstract: The invention is directed to a magnetic recording/reproducing system wherein each burst pattern in discrete media is configured in a substantially trapezoidal shape (truncated quadrangular pyramid shape, and which satisfies given relations between W1, W2, Tp and Wr. W1 is the upper side of the trapezoidal shape in the track width direction, which corresponds to the surface of said convex-form magnetic recoding layer, W2 is the lower side of the trapezoidal shape in the track width direction, which corresponds to the bottom surface of said convex-form magnetic layer, Tp is the data track pitch at the data information recording portion, and Wr is the read width of the magnetic head, so that loads on burst pattern shape in medium fabrication processes can be far more reduced and far more precise position error signals can be obtained.
    Type: Grant
    Filed: January 18, 2006
    Date of Patent: July 22, 2008
    Assignee: TDK Corporation
    Inventors: Katsumichi Tagami, Kazuya Shimakawa
  • Publication number: 20080170331
    Abstract: A magnetic recording medium is provided, which has recording layers having concavo-convex patterns formed on both sides of a substrate and can easily distinguish one face from the other face. A magnetic recording and reproducing apparatus having the magnetic recording medium is also provided. The magnetic recording medium includes a substrate, a first recording layer formed in a first concavo-convex pattern on a side of a first face, and a second recording layer formed in a second concavo-convex pattern on a side of a second face. The magnetic recording medium also includes a distinction element which can distinguish the first face from the second face. At least part of the distinction element is disposed in a non-recording area adjacent to at least one of an inner part and an outer part of a recording area in a radial direction.
    Type: Application
    Filed: January 3, 2008
    Publication date: July 17, 2008
    Applicant: TDK CORPORATION
    Inventors: Daisuke Yoshitoku, Minoru Fujita, Narutoshi Fukuzawa
  • Patent number: 7397624
    Abstract: A ferroelectric transducer for use with a ferroelectric storage medium includes a read electrode. The read electrode emits a current when a polarity orientation of the read electrode is opposite a polarity orientation of a ferroelectric domain on the storage medium.
    Type: Grant
    Filed: November 6, 2003
    Date of Patent: July 8, 2008
    Assignee: Seagate Technology LLC
    Inventors: Earl C. Johns, Mark I. Lutwyche, Yiao-Tee Hsia, James D. Kiely
  • Patent number: 7394622
    Abstract: A magnetic recording medium comprises a magnetically soft underlayer having a plurality of cavities in a surface thereof, and a magnetic recording material in the cavities, wherein a surface of the magnetic recording material in the cavities is substantially coplanar with the surface of the soft underlayer. A recording system that includes the recording medium is also included.
    Type: Grant
    Filed: December 7, 2004
    Date of Patent: July 1, 2008
    Assignee: Seagate Technology LLC
    Inventors: Edward Charles Gage, Gary Clark Rauch, Rene Johannes Marinus van de Veerdonk, Hans Juergen Richter, Terry Wayne McDaniel, Mark H. Kryder
  • Publication number: 20080152794
    Abstract: An information storage device using movement of magnetic domain walls includes a writing magnetic layer having a magnetic domain wall. A stack structure is formed on the writing magnetic layer. The stack structure includes a connecting magnetic layer and an information storing magnetic layer stacked sequentially. The information storage device also includes a reader for reading information stored in the information storing magnetic layer.
    Type: Application
    Filed: October 31, 2007
    Publication date: June 26, 2008
    Inventors: Chee-kheng Lim, Eun-hyoung Cho, Sung-hoon Choa
  • Patent number: 7391592
    Abstract: A magnetic recording medium having a diamond-like carbon (DLC) film added therein a Group IV element of the periodic table such as silicon, particularly in the vicinity of the boundary between the magnetic material and the formed DLC film. Since a DLC having low friction coefficient can be formed, the centerline average roughness can be reduced to 30 nm or even less. Accordingly, a magnetic recording medium improved in magnetic properties and in lubricity can be obtained.
    Type: Grant
    Filed: July 26, 2006
    Date of Patent: June 24, 2008
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Shigenori Hayashi
  • Publication number: 20080144219
    Abstract: Embodiments of the invention generally relate to PFPE lubricants, and more specifically to increasing the conductivity of PFPE lubricants. PFPE lubricants generally have low polarity and do not dissolve most conductive additives that tend to be highly polar. However, hydrophobic ionic liquids are highly fluorinated and have low polarity. Therefore, the hydrophobic ionic liquids may be dissolved in a PFPE lubricant to increase the conductivity of the PFPE lubricant.
    Type: Application
    Filed: December 19, 2006
    Publication date: June 19, 2008
    Inventors: John M. Burns, Malika D. Carter, Cynthia Delenia
  • Patent number: 7385785
    Abstract: A magnetic recording medium is provided, which includes a recording layer formed in a concavo-convex pattern to achieve high areal density and can ensure good recording and reproduction characteristics so as to provide high reliability. The magnetic recording medium has a substrate and a recording layer formed in the predetermined concavo-convex pattern over the substrate. The recording layer has a non-recording element and recording elements. The non-recording element is formed as convex portion of the concavo-convex pattern at an outer circumferential end and/or an inner circumferential end. The recording elements are formed as convex portions of the concavo-convex pattern in a region other than a region where the non-recording element is arranged.
    Type: Grant
    Filed: September 8, 2005
    Date of Patent: June 10, 2008
    Assignee: TDK Corporation
    Inventors: Kazuhiro Hattori, Kazuya Shimakawa
  • Publication number: 20080130157
    Abstract: A recording medium (100) on which record information is recorded, wherein the recording medium is displaced relatively with respect to a recording/reproducing device (60) for performing at least one of recording and reproduction of the record information, along each of one direction (X-axis) and another direction (Y-axis), and a track (120) which is a guide in recording the record information is formed such that a relative displacement direction of the recording/reproducing device due to the at least one of recording and reproduction of the record information is distributed substantially uniformly in both the one direction and the another direction.
    Type: Application
    Filed: November 17, 2005
    Publication date: June 5, 2008
    Applicant: PIONEER CORPORATION
    Inventors: Takanori Maeda, Kiyoshi Tateishi, Atsushi Onoe, Kazuo Takahashi
  • Publication number: 20080123209
    Abstract: A rotary-type magnetic recording medium has servo patterns formed in servo pattern regions on a substrate by patterns including recording regions and non-recording regions. Burst signal units composed of the recording regions or the non-recording regions are formed in burst pattern regions in the servo pattern regions. The burst signal units are formed so that for at least one edge out of both edges along a direction of rotation of the magnetic recording medium, a center in the direction of rotation is positioned closer to the other edge than both ends in the direction of rotation, and a ratio of a length along a radial direction of the magnetic recording medium between both ends and the center of the one edge to a length along the radial direction between both ends of the one edge and both ends of the other edge is in a range of 0.2 or below.
    Type: Application
    Filed: November 23, 2007
    Publication date: May 29, 2008
    Applicant: TDK CORPORATION
    Inventors: Katsuyuki NAKADA, Mitsuru TAKAI, Kazuhiro HATTORI
  • Publication number: 20080117548
    Abstract: A storage device includes a drive selection section (1), a hard disk drive (HDD) (2), and a non-volatile memory drive (3). When an instruction such as a data I/O instruction is issued from a host such as a CPU (5) and an ATA controller (6) to the hard disk drive (HDD) (2), the drive selection section (1) receives the address value. If the address value is included in the address space predefined, the non-volatile memory drive (3) is made to execute the instruction. Otherwise, the hard disk drive (HDD) (2) is made to execute the instruction.
    Type: Application
    Filed: July 5, 2004
    Publication date: May 22, 2008
    Inventors: Shuichiro Azuma, Masahiro Matsumoto, Takayuki Okinaga, Shigeru Takemura, Yoshiyuki Kimata, Takayuki Kishimoto
  • Publication number: 20080117544
    Abstract: According to one embodiment, a magnetic recording medium includes a substrate, and a magnetic recording layer formed on the substrate and having patterns of protrusions and recesses corresponding to a servo area and a recording area, in which the magnetic recording layer located in each of the recesses in the recording area has a thickness smaller than two thirds of a thickness of the magnetic recording layer corresponding to each of the protrusions, the magnetic recording layer remaining in each of the recesses in the recording area has a thickness of 1 nm or more, and a difference in height on a surface of the magnetic recording medium is 7 nm or less.
    Type: Application
    Filed: November 20, 2007
    Publication date: May 22, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Masatoshi Sakurai, Yoshiyuki Kamata, Satoshi Shirotori
  • Publication number: 20080106821
    Abstract: Provided is a patterned magnetic recording medium including a plurality of magnetic recording layers arranged at predetermined regular intervals on a substrate, wherein the magnetic recording layers are multi-layered and comprise a means of suppressing magnetic interaction between the magnetic recording layers. The magnetic recording layer includes a first ferromagnetic layer, the means of suppressing magnetic interaction, and a second ferromagnetic layer sequentially stacked, wherein the means of suppressing magnetic interaction is a soft magnetic layer.
    Type: Application
    Filed: May 31, 2007
    Publication date: May 8, 2008
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Chee-kheng Lim, Jin-seung Sohn, Byung-kyu Lee
  • Patent number: 7368186
    Abstract: The master carrier for magnetic transfer of the invention comprises a support and a magnetic layer formed on the surface of the support, wherein an uneven transfer pattern that corresponds to the information to be transferred to a magnetic recording medium is formed in the surface of the magnetic layer, and a relief is formed in the site where the transfer pattern is not formed.
    Type: Grant
    Filed: July 23, 2004
    Date of Patent: May 6, 2008
    Assignee: FUJIFILM Corporation
    Inventors: Naoto Fujiwara, Seiji Kasahara, Kazuhiro Niitsuma
  • Patent number: 7368184
    Abstract: A magnetic recording medium which has a high areal density and reduced power consumption for recording operations, and a magnetic recording device incorporating the magnetic recording medium. The magnetic recording medium has an upper soft magnetic layer formed uniformly along a plane including the upper surface of a recording layer over the convex and concave portions of a concavo-convex pattern in the recording layer.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: May 6, 2008
    Assignee: TDK Corporation
    Inventors: Akimasa Kaizu, Yoshikazu Soeno
  • Publication number: 20080100964
    Abstract: A magnetic recording disk drive has a bilayer recording medium of a high-anisotropy recording layer and an exchange-coupled antiferromagnetic-to-ferromagnetic (AF-F) transition layer. The transition layer has an AF-F transition temperature (TAF-F) that decreases relatively rapidly with increasing applied magnetic field. Thus the transition layer has a transition field HAF-F(T), which is the applied magnetic field required to transition the material from antiferromagnetic to ferromagnetic at temperature T without the need to heat the layer. At ambient temperature and in the absence of HW, the transition layer is antiferromagnetic and the switching field H0 of the bilayer is just the H0 of the high-anisotropy recording layer, which is typically much higher than HW.
    Type: Application
    Filed: October 26, 2006
    Publication date: May 1, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Eric Edward Fullerton, Stefan Maat, Ian Robson McFadyen, Jan-Ulrich Thiele
  • Publication number: 20080084635
    Abstract: Provided are a magnetic recording medium and a method of manufacturing the magnetic recording medium. The magnetic recording medium includes a substrate, a soft magnetic underlayer formed on the substrate, a texturing layer formed on the soft magnetic underlayer and including a uniform pattern, and a recording layer including magnetic grains and a non-magnetic boundary region isolating the magnetic grains. The magnetic grains and the non-magnetic boundary region of the recording layer are formed into a regular granular structure by segregation according to the regular pattern of the texturing layer. Therefore, a regular granular structure can be formed in the recording layer without a process such as etching of the recording layer, so that the recording density of the magnetic recording medium can be largely improved.
    Type: Application
    Filed: May 15, 2007
    Publication date: April 10, 2008
    Applicant: SAMSUNG ELECTRONICS CO., LTD
    Inventors: Du-hyun LEE, Seong-yong YOON, Jin-seung SOHN, Byung-kyu LEE
  • Patent number: 7351445
    Abstract: The present invention is directed to carrying out a high density magnetic recording to a material having a large coercive force by perpendicular magnetic recording head. By giving a patterning onto a soft magnetic under layer of a perpendicular two-layer recording media in sync with a period of a recording bit, a magnetic field from a write head can be allowed to converge to a soft magnetic column. Therefore, a magnetization reversal of the magnetic recording media material having a large anisotropic constant becomes possible, and then a high density magnetic recording can be achieved.
    Type: Grant
    Filed: June 12, 2006
    Date of Patent: April 1, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Chiseki Haginoya, Kaori Suzuki, Hisashi Kimura, Masaaki Futamoto, Hideo Matsuyama
  • Patent number: 7352529
    Abstract: A magnetic recording medium including at least a disk substrate 1A, a magnetic recording layer 5 formed with a predetermined concavo-convex pattern on the disk substrate 1A, and a non-magnetic layer 6 filled into concave portions of the concavo-convex pattern, so as to have data track regions 20 and servo pattern regions 21. Due to the existence of concaves and convexes in the surface of each servo pattern region 21, the foregoing problem is solved. On this occasion, arithmetical mean deviation of the assessed profile Ra of the surface of each servo pattern region 21 is preferably not lower than 0.3 nm. The difference in surface level between each concave and each convex existing in the surface of the servo pattern region 21 is preferably not larger than 6 nm.
    Type: Grant
    Filed: February 22, 2005
    Date of Patent: April 1, 2008
    Assignee: TDK Corporation
    Inventors: Mikiharu Hibi, Kazuhiro Hattori, Kazuya Shimakawa
  • Publication number: 20080074788
    Abstract: A disk for a hard disk drive. The disk includes a protective layer of shape memory alloy material over a magnetic layer. Contact between a head of the drive and the shape memory alloy material will cause frictional heat. The heat will cause a solid-solid phase transformation of the shape memory alloy material that will absorb energy and reduce wear. After head-disk contact terminates the shape memory alloy material will resume its initial solid phase. The shape memory alloy material may be relatively thin thereby improving the magnetic characteristics of the disks while providing a protective coating.
    Type: Application
    Filed: September 21, 2006
    Publication date: March 27, 2008
    Inventors: Chao Yuan Chen, Xiaoguang Ma, Michael Sullivan
  • Publication number: 20080068754
    Abstract: An apparatus, system, and method are disclosed for variable data density patterned media. The apparatus includes a patterned media recording surface comprising a plurality of sectors. Each sector may include a synchronization region configured to generate a signal in a read head, a first data region with a first data density configured to generate a signal with a first frequency, and at least a second data region with a second data density configured to generate a signal with a second frequency. The system includes a hard disk drive and the apparatus. The method includes sensing a signal in a read head, synchronizing the frequency and phase of a write clock with a predetermined frequency and phase of a synchronization region, and modifying the frequency of the write clock after a period of time determined in response to at least one physical characteristic of the disk.
    Type: Application
    Filed: September 15, 2006
    Publication date: March 20, 2008
    Inventor: Thomas R. Albrecht
  • Publication number: 20080070065
    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: Application
    Filed: September 14, 2006
    Publication date: March 20, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Andreas Klaus Berger, Hoa Van Do, Byron Hassberg Lengsfield, Natacha F. Supper
  • Publication number: 20080062562
    Abstract: According to one embodiment, an information processing apparatus includes a disk drive capable of writing data to a disk on which data can be written, a storage device configured to store data to be written on the disk, priority setting unit for setting priorities of the data stored in the storage device in a case of writing the data on the disk, and writing unit for writing the data stored in the storage device, with the higher priorities set by the priority setting unit, on an outer periphery of the disk.
    Type: Application
    Filed: September 6, 2007
    Publication date: March 13, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshihiro Kaneko, Yoji Nagao
  • Publication number: 20080062560
    Abstract: The disclosure pertains to a scratch effect controller wherein the lower surface of the user manipulated disc and the upper surface of the rotary platter are made of low friction material. The lower surface of the user manipulated disc and the upper surface of the rotary platter impinge against each other creating an area of low friction, thereby eliminating the need for a slip disc.
    Type: Application
    Filed: September 13, 2006
    Publication date: March 13, 2008
    Inventors: James Mazur, Alan Flum
  • Publication number: 20080055777
    Abstract: A scratch erasure resistant perpendicular magnetic recording medium comprises a non-magnetic substrate having a surface, and a layer stack formed over the surface and comprising: (i) at least one magnetically hard perpendicular magnetic recording layer; and (ii) at least one low shear modulus layer comprising at least one material having a shear modulus not greater than about 30 GPa. Preferably, the at least one magnetically hard perpendicular magnetic recording layer includes at least a first layer comprised of a magnetic material having a hexagonal close packed (hcp) crystal structure and <0001> preferred basal plane crystallographic orientation with c-axis perpendicular to a surface thereof.
    Type: Application
    Filed: September 6, 2006
    Publication date: March 6, 2008
    Inventors: Shanghsien (Alex) Rou, Qixu (David) Chen, Raj N. Thangaraj, Huan Tang, Xinwei Li, Jing Gui
  • Patent number: 7339764
    Abstract: A method of designing a patterned magnetic recording medium including a magnetic film with perpendicular magnetic anisotropy which is patterned into dots form includes steps of setting values to dot pattern periods Px and Py, a thickness “t”, a thermal stability factor Kn, a minimum inter-dot spacing S0, and a maximum recording field Hm, setting an initial value of a saturation magnetization Ms, finding a nucleation field for magnetization reversal Hn and estimating a coercivity Hc and a saturation field Hs, and repeating the steps given above so as to make the saturation field Hs lower than the maximum recording field Hm, thereby determining the magnetic properties Ms, Hn and Hc satisfying a desired condition.
    Type: Grant
    Filed: March 22, 2007
    Date of Patent: March 4, 2008
    Assignees: Japan Science and Technology Agency, Akita Prefecture
    Inventors: Naoki Honda, Kazuhiro Ouchi