Patents by Inventor Mariko Shimizu

Mariko Shimizu 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: 8547662
    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: Grant
    Filed: July 3, 2012
    Date of Patent: October 1, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kenichiro Yamada, Hitoshi Iwasaki, Junichi Akiyama, Masayuki Takagishi, Tomomi Funayama, Masahiro Takashita, Mariko Shimizu, Shuichi Murakami, Tadashi Kai
  • Publication number: 20130187238
    Abstract: According to one embodiment, a semiconductor device includes a first semiconductor layer of a first conductivity type, a second semiconductor layer of a first conductivity type, a third semiconductor layer of a second conductivity type, an isolation layer, and a guard ring layer of the second conductivity type. The second semiconductor layer is provided on the first semiconductor layer. The third semiconductor layer is provided on the second semiconductor layer to be joined to the second semiconductor layer. The isolation layer surrounds a periphery of the third semiconductor layer and is deeper than the third semiconductor layer. The guard ring layer is provided between the third semiconductor layer and the isolation layer, adjacent to the third semiconductor layer, and deeper than the third semiconductor layer.
    Type: Application
    Filed: June 11, 2012
    Publication date: July 25, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Koji Shirai, Mariko Shimizu
  • Patent number: 8421153
    Abstract: A first semiconductor layer extends from the element region to the element-termination region, and functions as a drain of the MOS transistor. A second semiconductor layer extends, below the first semiconductor layer, from the element region to the element-termination region. A third semiconductor layer extends from the element region to the element-termination region, and is in contact with the second semiconductor layer to function as a drift layer of the MOS transistor. A distance between a boundary between the first semiconductor layer and the field oxide film, and the end portion of the third semiconductor layer on the fifth semiconductor layer side in the element region is smaller than that between a boundary between the first semiconductor layer and the field oxide layer and an end portion of the third semiconductor layer on the fifth semiconductor layer side in the element-termination region.
    Type: Grant
    Filed: September 22, 2011
    Date of Patent: April 16, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kanako Komatsu, Jun Morioka, Koji Shirai, Keita Takahashi, Tsubasa Yamada, Mariko Shimizu
  • Patent number: 8400734
    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: March 19, 2013
    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: 8325442
    Abstract: A spin torque oscillator includes a first magnetic layer, a second magnetic layer and a first nonmagnetic layer. The first magnetic layer includes a magnetic film of a magnetic material with a body-centered cubic (bcc) structure and an oriented {110} plane of the body-centered cubic structure, the oriented {110} plane being oriented substantially parallel to a principal plane of the magnetic film. The first nonmagnetic layer is disposed between the first magnetic layer and the second magnetic layer. In addition, a magnetic moment in the magnetic film precesses around an axis substantially parallel to the principal plane. Furthermore, a magnetic field is applied in a direction substantially perpendicular to the principal plane, and a current is passed perpendicularly to the principal plane.
    Type: Grant
    Filed: November 5, 2009
    Date of Patent: December 4, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsuhiko Koui, Mariko Shimizu, Kenichiro Yamada
  • 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
  • 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
  • Publication number: 20120241858
    Abstract: A first semiconductor layer extends from the element region to the element-termination region, and functions as a drain of the MOS transistor. A second semiconductor layer extends, below the first semiconductor layer, from the element region to the element-termination region. A third semiconductor layer extends from the element region to the element-termination region, and is in contact with the second semiconductor layer to function as a drift layer of the MOS transistor. A distance between a boundary between the first semiconductor layer and the field oxide film, and the end portion of the third semiconductor layer on the fifth semiconductor layer side in the element region is smaller than that between a boundary between the first semiconductor layer and the field oxide layer and an end portion of the third semiconductor layer on the fifth semiconductor layer side in the element-termination region.
    Type: Application
    Filed: September 22, 2011
    Publication date: September 27, 2012
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Kanako Komatsu, Jun Morioka, Koji Shirai, Keita Takahashi, Tsubasa Yamada, Mariko Shimizu
  • 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
  • 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: 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: 20110300409
    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