Patents Assigned to Hitachi Global Storage Technologies
  • Patent number: 9177111
    Abstract: A software protection system comprises a memory system and a microprocessing system. The memory system is configured to store a software program comprised of a plurality of program instructions that, when executed, have a program order. The microprocessing system is coupled to the memory system and is configured to, when executing the software program, determine a next program instruction of the plurality of program instructions in the program order based on an order identifier, fetch the next program instruction from the memory system, determine if the next program instruction requires decrypting, decrypt the next program instruction responsive to determining that the next program instruction requires decrypting, and execute the next program instruction.
    Type: Grant
    Filed: November 14, 2006
    Date of Patent: November 3, 2015
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Christopher J. Squires, Jeffrey G. Reh
  • Patent number: 8638527
    Abstract: A signaling method and apparatus for providing two write assist components for perpendicular thin film heads writing to high coercivity media is disclosed. The two components provided by the present invention include a media writing assist component and a head switching assist component. Circuit wiring configurations and waveforms for driving an auxiliary half coil are disclosed. These include configurations for connecting the auxiliary half coil in parallel with the main data coil, or connecting the auxiliary half coil to the thermal flight control system. Provision for both common mode signals as well as differential mode signals are disclosed. RF sinusoidal waveforms between 1 and 5 GHz have been found suitable for head switching assist functions for either symmetric current feed and common mode current configuration, or asymmetric current feed and differential mode current configuration.
    Type: Grant
    Filed: October 16, 2009
    Date of Patent: January 28, 2014
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Luiz M. Franca-Neto, Bernhard E. Knigge, Petrus Antonius Van Der Heijden
  • Publication number: 20140002927
    Abstract: A magnetic write head for magnetic data recording that includes a structure having a low coefficient of thermal expansion for controlling thermal expansion of the write head. The structure having a low coefficient of thermal expansion has a shape that substantially conforms to the shape of the write coil, such that both the write coil and the structure having a low coefficient of thermal expansion have a central portion that is located closest to the air bearing surface and outer end portions that bend away from the air bearing surface to form a horseshoe shape.
    Type: Application
    Filed: June 28, 2012
    Publication date: January 2, 2014
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Wen-Chien D. Hsiao, Terence T.L. Lam, Yansheng Luo, Xinjiang Shen
  • Publication number: 20130342937
    Abstract: A magnetic write head having a main magnetic write pole and a magnetic sub-pole that are configured to maximize magnetic performance. The main magnetic write pole has a flared portion located near the air bearing surface and a non-flared portion removed from the air bearing surface. A magnetic sub-pole is formed adjacent to the main magnetic write pole and terminates at a front endpoint that is recessed from the air bearing surface but is closer to the air bearing surface than the non-flared portion.
    Type: Application
    Filed: June 21, 2012
    Publication date: December 26, 2013
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Mikito Sugiyama, Kazuhiko Hosomi, Kaori Suzuki
  • Publication number: 20130308228
    Abstract: A magnetic sensor having reduced read gap thickness, reduced signal noise and improved signal to noise ratio. The sensor includes a sensor stack and hard bias structures formed at either side of the sensor stack for biasing the free layer of the sensor. A protective layer is formed over a portion of the hard bias structure, however a portion of the hard bias structure extends upward toward the upper shield and is disposed between the protective layer and the sensor stack as a result of the process used to form the magnetic bias structure. This portion of the hard bias structure that extends toward the upper shield has a reduced magnetization relative to the rest of the hard bias structure so that it will not magnetically couple with the upper shield.
    Type: Application
    Filed: May 15, 2012
    Publication date: November 21, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hideki Mashima, Nobuo Yoshida, Takahiro Ibusuki, Tsutomu Yasuda
  • Publication number: 20130301157
    Abstract: In one embodiment, a magnetic recording medium includes a magnetic recording layer including a magnetic material characterized by having convex and concave portions, the convex portions acting as magnetic regions, a nonmagnetic material positioned within each concave portion of the magnetic material which act as nonmagnetic regions that separate the magnetic regions, an organic material layer which exhibits a corrosion-inhibiting characteristic with respect to cobalt or cobalt alloy positioned on a nonmagnetic region side of each concave portion, and an oxide layer and/or hydroxide layer positioned adjacent the organic material layer on a magnetic region side of each concave portion of the magnetic material. In another embodiment, the magnetic recording medium may be a patterned recording layer having a protective film, and the oxide layer and/or hydroxide layer may be positioned at least in defect portions of the protective film.
    Type: Application
    Filed: May 8, 2012
    Publication date: November 14, 2013
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Qing Dai, Bruno Marchon, Katsumi Mabuchi, Mina Amo
  • Publication number: 20130284693
    Abstract: A method for manufacturing a magnetic read sensor allows for the construction of a very narrow trackwidth sensor while avoiding problems related to mask liftoff and shadowing related process variations across a wafer. The process involves depositing a plurality of sensor layers and forming a first mask structure. The first mask structure has a relatively large opening that encompasses a sensor area and an area adjacent to the sensor area where a hard bias structure can be deposited. A second mask structure is formed over the first mask structure and includes a first portion that is configured to define a sensor dimension and a second portion that is over the first mask structure in the field area.
    Type: Application
    Filed: April 27, 2012
    Publication date: October 31, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Yi Zheng, Guomin Mao, Hicham M. Sougrati, Xiaozhong Dang
  • Publication number: 20130279045
    Abstract: A head for magnetic thermally assisted magnetic data recording, having a read element, a write element a heater element for controlling thermal protrusion of the read and write elements and a thermal sensor for detecting contact a portion of the head with a magnetic media. The thermal contact sensor is arranged so that the thermal conduction between the thermal contact sensor and the read element is substantially equal to the thermal conductivity between the thermal contact sensor and the write element. In this way the accuracy of the detection of thermal contact is maintained whether the read element makes contact with the disk or the write element makes contact with disk.
    Type: Application
    Filed: April 19, 2012
    Publication date: October 24, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hiroshi Agari, Hideaki Tanaka, Yoshinori Takeuchi, Koichi Watanabe, Minoru Koike, Koji Tanaka
  • Publication number: 20130268718
    Abstract: A method, apparatus, and a storage system are provided for implementing enhanced indirection update for indirected storage devices. A novel remapping command generated by a host is used to store indirection data. The remapping command enables remapping of a set of Logical Block Addresses (LBAs) to a different set of LBAs. The remapping command includes a source LBA, length and a destination LBA.
    Type: Application
    Filed: April 9, 2012
    Publication date: October 10, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: David Robison Hall
  • Publication number: 20130242431
    Abstract: A magnetic write head having a shield structure that provides both a leading shield and side shielding function. The magnetic shield is separated from the sides and leading edge of the write pole by a non-magnetic gap layer that has a non-uniform thickness. The non-magnetic gap layer is thicker near the leading edge and thinner at the trailing edge. This allows for increased side field gradient near the trailing edge of the write pole and decreased write field loss at the leading edge of the write pole.
    Type: Application
    Filed: March 13, 2012
    Publication date: September 19, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kazuhiko Hosomi, Kimitoshi Eto, Mikito Sugiyama, Junichi Hashimoto, Kazue Kudo, Misuzu Kanai
  • Publication number: 20130237131
    Abstract: A method of polishing workpieces includes final tape polishing (FTP) a media disk by rotating the media disk; applying a liquid that is substantially pure to the media disk adjacent to an FTP tape; applying the FTP tape to the media disk at a pad load to polish the media disk, such that the liquid acts as a transient lubricant between the media disk and the FTP tape; and completing FTP. The FTP process is completely independent of the final disk lubricant, such that the final disk lubricant may be applied before or after FTP.
    Type: Application
    Filed: March 7, 2012
    Publication date: September 12, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Xing-Cai Guo, Thomas E. Karis, Bruno Marchon
  • Publication number: 20130235491
    Abstract: A heat enabled magnetic media having a composite magnetic recording layer structure that includes first and second magnetic layers and an exchange coupling layer sandwiched between the first and second magnetic layers. The exchange coupling layer has a reduced Curie temperature that allows the magnetic layers to become decoupled a lower temperature. This reduced Curie temperature can be achieved the addition of an alloying element such as Ni or Cu into the exchange coupling layer. Therefore, the exchange coupling layer can be constructed of an alloy such as FePtNi FePtCu, and the magnetic layers can be constructed of a material such as FePt.
    Type: Application
    Filed: March 9, 2012
    Publication date: September 12, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Oleksandr Mosendz, Hans J. Richter
  • Publication number: 20130236987
    Abstract: A method of fabricating workpieces includes one or more layers on a substrate that are masked with an ion implantation mask comprising two or more layers. The mask layers include a first mask layer closer to the substrate, and a second mask layer on the first mask layer. The method also comprises ion implanting one or more of the layers on the substrate. Ion implantation may form portions with altered physical properties from the layers under the mask. The portions may form a plurality of non-magnetic regions corresponding to apertures in the mask.
    Type: Application
    Filed: March 8, 2012
    Publication date: September 12, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kanaiyalal C. Patel, Kurt A. Rubin
  • Publication number: 20130229728
    Abstract: A magnetic head according to one embodiment includes a nonmagnetic gap layer in a trench; a pole seed layer above the nonmagnetic gap layer; and a pole layer of a magnetic material above the pole seed layer, wherein at least one of the nonmagnetic gap layer, the pole seed layer and the pole layer has nitrogen therein. A magnetic head according to another embodiment includes a nonmagnetic gap layer in a trench; a pole seed layer above the nonmagnetic gap layer, the pole seed layer being comprised primarily of a material selected from a group consisting of NiCr, Ta/Ru, Ta/Rh, NiCr/Ru, NiCr/Rh, NiCr, CoOx, Ru, Rh, Cu, Au/MgO, Ta/Cu; and a pole layer comprised primarily of CoFe above the pole seed layer, wherein at least one of the nonmagnetic gap layer, the pole seed layer and the pole layer has nitrogen therein.
    Type: Application
    Filed: March 2, 2012
    Publication date: September 5, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Elizabeth A. Brinkman, Ning Shi, Brian R. York
  • Publication number: 20130232292
    Abstract: A method and a storage system are provided for implementing a sustained large block random write performance mechanism for shingled magnetic recording (SMR) drives in a redundant array of inexpensive disks (RAID). A Solid State Drive (SSD) is provided with the SMR drives in the RAID. The SSD is used in a hot spare mode, which is activated when a large block random-write event is identified for a SMR drive in the RAID. In the hot spare mode, the SSD temporarily receives new incoming writes for the identified SMR drive. Then the identified SMR drive is updated from the SSD to restore the state of the identified SMR drive, and operations continue with normal writing only using the SMR drives in the RAID.
    Type: Application
    Filed: March 1, 2012
    Publication date: September 5, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B. V.
    Inventors: Zvonimir Z. Bandic, Cyril Guyot, Tomohiro Harayama, Hitoshi Kamei, Takaki Nakamura, Timothy Tsai
  • Publication number: 20130215530
    Abstract: In one embodiment, a magnetic data storage system includes a main pole power supply adapted for supplying an excitation current to a main pole coil, a microwave-assisted magnetic recording (MAMR) device including a spin-torque oscillator (STO) element, the STO element having a field generation layer (FGL) and a polarization layer, a timing-control circuit adapted for determining a duration of a main pole magnetic moment inversion process and signaling a start of the main pole magnetic moment inversion process, and a current-regulating circuit comprising an STO power supply adapted for supplying current to the STO element, wherein the STO power supply prevents degradation of a single rotating magnetic domain structure in the FGL into a closure magnetic domain structure in the FGL. Other systems and methods for preventing degradation of the single rotating magnetic domain structure in the FGL into a closure magnetic domain structure are described for more embodiments.
    Type: Application
    Filed: February 21, 2012
    Publication date: August 22, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masukazu Igarashi, Masato Matsubara, Keiichi Nagasaka, Masato Shiimoto
  • Publication number: 20130194865
    Abstract: A method and apparatus are provided for implementing enhanced data read for multi-level cell (MLC) memory using threshold-voltage-drift or resistance-drift tolerant moving baseline memory data encoding. A data read back for data written to the MLC memory using threshold-voltage-drift or resistance-drift tolerant moving baseline memory data encoding is performed, higher voltage and lower voltage levels are compared, and respective data values are identified responsive to the compared higher voltage and lower voltage levels.
    Type: Application
    Filed: January 30, 2012
    Publication date: August 1, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Zvonimir Z. Bandic, Luiz M. Franca-Neto, Cyril Guyot, Robert Eugeniu Mateescu
  • Publication number: 20130194693
    Abstract: According to one embodiment, a lubricant includes a perfluoropolyether having a chemical structure of wherein Rf is at least one of —CF2O(CF2CF2O)m(CF2O)nCF2— and —CF2CF2O(CF2CF2CF2O)kCF2CF2—, with m representing 0 or a positive integer, n representing 0 or a positive integer, and k representing 0 or a positive integer, and wherein R1 to R4 are selected from a group consisting of —H or with at least one of R1 to R4 being
    Type: Application
    Filed: January 30, 2012
    Publication date: August 1, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Mina Amo, Katsumi Mabuchi, Hiroshi Yoshida, Bruno Marchon, Qing Dai
  • Publication number: 20130194864
    Abstract: A method and apparatus are provided for implementing enhanced performance for multi-level cell (MLC) memory using threshold-voltage-drift or resistance-drift tolerant moving baseline memory data encoding. A voltage baseline of a prior write is identified, and a data write uses the threshold-voltage-drift or resistance-drift tolerant moving baseline memory data encoding for data being written to the MLC memory responsive to the identified voltage baseline.
    Type: Application
    Filed: January 30, 2012
    Publication date: August 1, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Zvonimir Z. Bandic, Luiz M. Franca-Neto, Cyril Guyot, Robert Eugeniu Mateescu
  • Publication number: 20130198436
    Abstract: A method and apparatus are provided for implementing enhanced data partial erase for multi-level cell (MLC) memory using threshold-voltage-drift or resistance-drift tolerant moving baseline memory data encoding. A data partial erase for data written to the MLC memory using threshold-voltage-drift or resistance-drift tolerant moving baseline memory data encoding is performed, and a data re-write after the partial erase to the MLC memory is performed using threshold-voltage-drift or resistance-drift tolerant moving baseline memory data encoding. A data partial erase cycle includes a duration and voltage level based upon a degradation of the MLC memory cells.
    Type: Application
    Filed: January 30, 2012
    Publication date: August 1, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Zvonimir Z. Bandic, Luiz M. Franca-Neto, Cyril Guyot, Robert Eugeniu Mateescu