Patents by Inventor Masahiro Takashita

Masahiro Takashita has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8320079
    Abstract: It is made possible to reduce the write magnetic field generated from the main magnetic pole toward the spin torque oscillator, so as to reduce the variation in the oscillation characteristics of the spin torque oscillator, and reduce the current required for oscillation. The magnetic head assembly includes: a recording magnetic pole; a spin torque oscillator that has first and second magnetic layers, and an intermediate layer interposed between the first and second magnetic layers, the spin torque oscillator generating a high-frequency magnetic field by applying a current between the first and second magnetic layers; and a third magnetic layer that is placed adjacent to at least part of a side face of the second magnetic layer.
    Type: Grant
    Filed: June 17, 2009
    Date of Patent: November 27, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hitoshi Iwasaki, Kenichiro Yamada, Masayuki Takagishi, Tomomi Funayama, Masahiro Takashita, Mariko Shimizu, Soichi Oikawa, Katsuhiko Koui
  • Patent number: 8305716
    Abstract: An example magneto-resistance effect element includes a magnetization layer and a free magnetization layer of which magnetization direction changes depending on an external magnetic field. A spacer layer is located between the magnetization layer and the free magnetization layer, and has an insulating layer and an electric conductor passing current therethrough in a layer direction of the insulating layer. A diffusive electron scattering layer is disposed on said free magnetization layer for scattering diffusive electrons. The scattering layer includes a first nonmagnetic layer and a second nonmagnetic layer containing a first element and a second element, respectively, and a mixing layer disposed at a boundary between the first and second nonmagnetic layers and containing the first and second elements. The mixing layer has a thickness of 0.5 nm or more and 1.5 nm or less.
    Type: Grant
    Filed: January 27, 2012
    Date of Patent: November 6, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Masahiro Takashita, Hiromi Yuasa, Yoshihiko Fuji, Hitoshi Iwasaki
  • Publication number: 20120275061
    Abstract: According to one embodiment, a magnetic recording device includes a magnetic recording head and a magnetic recording medium. The magnetic recording head includes a main magnetic pole, a shield and a stacked structure. The main magnetic pole has a medium facing surface and a main magnetic pole side surface. The shield has a shield side surface. The stacked structure is provided between the main magnetic pole and shield, and includes first and second magnetic layers, and an intermediate layer. The magnetic recording medium includes a backing layer and a magnetic recording layer. A distance between an end portion of the medium facing surface on a side of the stacked structure and the backing layer is twice or more of a distance between the main magnetic pole side surface and the shield side surface.
    Type: Application
    Filed: April 30, 2012
    Publication date: November 1, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Masayuki TAKAGISHI, Hitoshi Iwasaki, Kenichiro Yamada, Katsuhiko Koui, Tomomi Funayama, Masahiro Takashita, Mariko Kitazaki, Soichi Oikawa
  • Publication number: 20120275060
    Abstract: An example magnetic head includes a recording magnetic pole to generate a recording magnetic field; a spin torque oscillator formed in the vicinity of the recording magnetic pole; and a hard bias film for applying a magnetic field to the spin torque oscillator.
    Type: Application
    Filed: July 10, 2012
    Publication date: November 1, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Mariko Shimizu, Hitoshi Iwasaki, Kenichiro Yamada, Junichi Akiyama, Masayuki Takagishi, Tomomi Funayama, Masahiro Takashita
  • Publication number: 20120268844
    Abstract: An example magnetic writing head includes a main magnetic pole, a coil to generate an ampere magnetic field to magnetize the main magnetic pole to cause the magnetized main magnetic pole to generate a magnetic field, and a laminated body. The laminated body includes a first magnetic layer having a coercivity lower than the magnetic field applied by the main magnetic pole and a second magnetic layer having a coercivity lower than the magnetic field applied by the main magnetic pole.
    Type: Application
    Filed: July 3, 2012
    Publication date: October 25, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Kenichiro Yamada, Hitoshi Iwasaki, Junichi Akiyama, Masayuki Takagishi, Tomomi Funayama, Masahiro Takashita, Mariko Shimizu, Shuichi Murakami, Tadashi Kai
  • Patent number: 8295009
    Abstract: An example magnetic recording head includes: a main magnetic pole; a laminated body; and a pair of electrodes. The laminated body includes a first magnetic layer having a coercivity lower than magnetic field applied by the main magnetic pole, a second magnetic layer having a coercivity lower than the magnetic field applied by the main magnetic pole, and an intermediate layer provided between the first magnetic layer and the second magnetic layer. The pair of electrodes is operable to pass a current through the laminated body.
    Type: Grant
    Filed: August 19, 2011
    Date of Patent: October 23, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kenichiro Yamada, Hitoshi Iwasaki, Junichi Akiyama, Masayuki Takagishi, Tomomi Funayama, Masahiro Takashita, Mariko Shimizu, Shuichi Murakami, Tadashi Kai
  • Patent number: 8270112
    Abstract: It is made possible to provide a magnetic head that generates a sufficient high-frequency magnetic field for assisting recording operations, and a magnetic recording device that includes the magnetic head. A magnetic head includes: a recording magnetic pole; a return yoke magnetically coupled to the recording magnetic pole; and at least two spin torque oscillators provided near the recording magnetic pole.
    Type: Grant
    Filed: September 16, 2008
    Date of Patent: September 18, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomomi Funayama, Kenichiro Yamada, Masayuki Takagishi, Masahiro Takashita, Mariko Shimizu, Junichi Akiyama, Hitoshi Iwasaki
  • Patent number: 8238060
    Abstract: A magnetic recording head includes: a main magnetic pole; a laminated body; and a pair of electrodes. The laminated body includes a first magnetic layer having a coercivity lower than magnetic field applied by the main magnetic pole, a second magnetic layer having a coercivity lower than the magnetic field applied by the main magnetic pole, and an intermediate layer provided between the first magnetic layer and the second magnetic layer. The pair of electrodes are operable to pass a current through the laminated body.
    Type: Grant
    Filed: May 14, 2010
    Date of Patent: August 7, 2012
    Inventors: Kenichiro Yamada, Hitoshi Iwasaki, Junichi Akiyama, Masayuki Takagishi, Tomomi Funayama, Masahiro Takashita, Mariko Shimizu, Shuichi Murakami, Tadashi Kai
  • Patent number: 8238058
    Abstract: According to one embodiment, a magnetic recording head includes a main magnetic pole, a shield, and a stacked structure body. The shield is provided to oppose the main magnetic pole. The stacked structure body is provided between the main magnetic pole and the shield. The stacked structure body includes a first magnetic layer, a second magnetic layer, and an intermediate layer. The first magnetic layer has coercivity lower than a magnetic field applied from the main magnetic pole. A size of a film surface of the second magnetic layer is larger than a size of a film surface of the first magnetic layer. The intermediate layer is provided between the first magnetic layer and the second magnetic layer and is made of a nonmagnetic material. A current is configured to pass between the first magnetic layer and the second magnetic layer.
    Type: Grant
    Filed: February 7, 2011
    Date of Patent: August 7, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Mariko Shimizu, Hitoshi Iwasaki, Kenichiro Yamada, Katsuhiko Koui, Masayuki Takagishi, Tomomi Funayama, Masahiro Takashita, Soichi Oikawa
  • Publication number: 20120170151
    Abstract: According to one embodiment, a recording track has a surface modification layer in the surface region. This surface modification layer has an anisotropic magnetic field Hk reduced from that of a region between adjacent recording tracks.
    Type: Application
    Filed: March 14, 2012
    Publication date: July 5, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Soichi OIKAWA, Hitoshi IWASAKI, Masayuki TAKAGISHI, Kenichiro YAMADA, Tomomi FUNAYAMA, Masahiro TAKASHITA, Katsuhiko KOUI, Mariko SHIMIZU
  • Publication number: 20120154952
    Abstract: A magnetic recorder includes: a magnetic recording medium; a reproducing head; a magnetic recording head including: a main magnetic pole; a first magnetic layer containing a TM alloy; a second magnetic layer containing a TM alloy or an RE-TM alloy; a third magnetic layer containing an RE-TM alloy; a first intermediate layer provided between the first magnetic layer and the second magnetic layer; and a second intermediate layer provided between the second magnetic layer and the third magnetic layer; and a signal processing portion which performs signal writing into the magnetic recording medium by using the magnetic recording head and reading from the magnetic recording medium by using the reproducing head.
    Type: Application
    Filed: February 24, 2012
    Publication date: June 21, 2012
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Kenichiro YAMADA, Hitoshi IWASAKI, Masayuki TAKAGISHI, Tomomi FUNAYAMA, Masahiro TAKASHITA, Katsuhiko KOUI, Mariko KITAZAKI, Soichi OIKAWA
  • Publication number: 20120129008
    Abstract: A magneto-resistance effect element, a magneto-resistance effect head, a magnetic storage and a magnetic memory, in which noise caused by a spin-transfer torque is reduced, are provided. In a fixed magnetization layer or a free magnetization layer of a magneto-resistance effect element including the fixed magnetization layer, a spacer layer and the free magnetization layer; a layer containing one element selected from the group consisting of Ti, Zr, Nb, Mo, Ru, Rh, Pd, Ag, La, Hf, Ta, W, Re, Os, Ir, Pt and Au is disposed.
    Type: Application
    Filed: January 27, 2012
    Publication date: May 24, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hideaki FUKUZAWA, Masahiro TAKASHITA, Hiromi YUASA, Yoshihiko FUJI, Hitoshi IWASAKI
  • Patent number: 8164854
    Abstract: A magnetic recording head includes a recording magnetic pole, and a spin oscillation device including a first magnetic layer having at least one magnetic material layer, a second magnetic layer having at least one magnetic material layer, and a first nonmagnetic layer provided between the first magnetic layer and the second magnetic layer. The first magnetic layer and the second magnetic layer are antiferromagnetically coupled and/or magnetostatically coupled to each other. The first magnetic layer and the second magnetic layer are laminated in a direction generally parallel to a medium facing surface and generally parallel to a side surface of the recording magnetic pole intersecting with the medium facing surface.
    Type: Grant
    Filed: June 4, 2008
    Date of Patent: April 24, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masayuki Takagishi, Kenichiro Yamada, Hitoshi Iwasaki, Junichi Akiyama, Tomomi Funayama, Masahiro Takashita, Mariko Shimizu
  • Patent number: 8154825
    Abstract: It is made possible to provide a magnetic head that can stabilize the high-frequency magnetic field generated from the spin torque oscillator. A magnetic head includes: first and second main magnetic poles; and a spin torque oscillator provided between the first and second main magnetic poles.
    Type: Grant
    Filed: September 16, 2008
    Date of Patent: April 10, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masahiro Takashita, Hitoshi Iwasaki, Kenichiro Yamada, Junichi Akiyama, Masayuki Takagishi, Tomomi Funayama, Mariko Shimizu
  • Patent number: 8139322
    Abstract: A magnetic recording head includes: a main magnetic pole; a laminated body; and a pair of electrodes operable to pass a current through the laminated body. The laminated body includes a first magnetic layer, a second magnetic layer, and an intermediate layer provided between the first magnetic layer and the second magnetic layer. A lamination direction of the laminated body is substantially parallel to a medium moving direction. In a first direction parallel to an air bearing surface and perpendicular to the lamination direction, the laminated body has a protruding portion that protrudes beyond an end of a surface of the main magnetic pole facing the laminated body.
    Type: Grant
    Filed: May 20, 2008
    Date of Patent: March 20, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kenichiro Yamada, Hitoshi Iwasaki, Junichi Akiyama, Masayuki Takagishi, Tomomi Funayama, Masahiro Takashita, Mariko Shimizu
  • Patent number: 8130477
    Abstract: A magneto-resistance effect element, a magneto-resistance effect head, a magnetic storage and a magnetic memory, in which noise caused by a spin-transfer torque is reduced, are provided. In a fixed magnetization layer or a free magnetization layer of a magneto-resistance effect element including the fixed magnetization layer, a spacer layer and the free magnetization layer; a layer containing one element selected from the group consisting of Ti, Zr, Nb, Mo, Ru, Rh, Pd, Ag, La, Hf, Ta, W, Re, Os, Ir, Pt and Au is disposed.
    Type: Grant
    Filed: September 10, 2010
    Date of Patent: March 6, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Masahiro Takashita, Hiromi Yuasa, Yoshihiko Fuji, Hitoshi Iwasaki
  • Patent number: 8125744
    Abstract: A current perpendicular to plane magneto-resistance effect element includes: a magneto-resistance effect film comprised of a fixed magnetization layer, a free magnetization layer, and a complex spacer layer including an insulating layer and current paths formed through the insulating layer; a biasing mechanism for stabilizing the free magnetization layer; a shielding mechanism for ensuring a reproducing resolution of the magneto-resistance effect element; and a pair of electrodes for flowing a current perpendicular to a film surface of the magneto-resistance effect element; wherein a resistance area product (RA:?×?m2) is set to 0.00062×?{square root over ((GAP))}×TW+0.06 when a track width of the magneto-resistance effect element is defined as TW (nm) and a gap length of the magneto-resistance effect element is defined as GAP (nm).
    Type: Grant
    Filed: March 18, 2008
    Date of Patent: February 28, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masayuki Takagishi, Hitoshi Iwasaki, Masahiro Takashita, Michiko Hara, Dan Abels, Xin Li
  • Patent number: 8120875
    Abstract: A magnetic recording apparatus includes a magnetic recording head having a magnetic pole and a spin torque oscillator, the spin torque oscillator being placed adjacent to the magnetic pole and includes at least two magnetic layers of a first magnetic layer and a second magnetic layer, and a magnetic recording medium includes two magnetic layers of a recording layer and an antenna layer, the recording layer including a hard magnetic material, such that the antenna layer is formed closer to the magnetic recording head than the recording layer, in which the antenna layer has a resonance frequency fa lower than a resonance frequency fr of the recording layer, greater than a resonance frequency of the second magnetic layer, and the recording layer and the antenna layer are ferromagnetically coupled to each other.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: February 21, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masayuki Takagishi, Kenichiro Yamada, Hitoshi Iwasaki, Tomomi Funayama, Masahiro Takashita, Mariko Shimizu
  • Patent number: 8081397
    Abstract: A magnetic head assembly includes a magnetic recording head, a main magnetic pole, a head slider, a suspension and an actuator arm. The magnetic recording head includes a main magnetic pole having an air bearing surface facing a magnetic recording medium; and a stacked structure having, a first magnetic layer, a second magnetic layer, and an intermediate layer provided between the first magnetic layer and the second magnetic layer. A stacked plane of the stacked structure is inclined with respect to the air bearing surface. The magnetic recording head is mounted on the head slider. The head slider is mounted on one end of the suspension. The actuator arm is connected to the other end of the suspension.
    Type: Grant
    Filed: June 18, 2009
    Date of Patent: December 20, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomomi Funayama, Kenichiro Yamada, Katsuhiko Koui, Hitoshi Iwasaki, Masayuki Takagishi, Masahiro Takashita, Mariko Shimizu, Soichi Oikawa
  • Publication number: 20110299192
    Abstract: An example magnetic recording head includes: a main magnetic pole; a laminated body; and a pair of electrodes. The laminated body includes a first magnetic layer having a coercivity lower than magnetic field applied by the main magnetic pole, a second magnetic layer having a coercivity lower than the magnetic field applied by the main magnetic pole, and an intermediate layer provided between the first magnetic layer and the second magnetic layer. The pair of electrodes is operable to pass a current through the laminated body.
    Type: Application
    Filed: August 19, 2011
    Publication date: December 8, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Kenichiro Yamada, Hitoshi Iwasaki, Junichi Akiyama, Masayuki Takagishi, Tomomi Funayama, Masahiro Takashita, Mariko Shimizu, Shuichi Murakami, Tadashi Kai