Patents by Inventor Masashi Sahashi

Masashi Sahashi 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: 11244781
    Abstract: A magnetization control element according to an aspect of the invention includes a magnetization control layer containing a magnetoelectric material exhibiting a magnetoelectric effect, and a magnetic coupling layer that is magnetically coupled to a magnetization of a first surface of the magnetization control layer through exchange coupling and exhibits a magnetic state according to the magnetization of the first surface, wherein a magnetization having a component in a direction opposite to a direction of a magnetization of the magnetic coupling layer is imparted to the magnetization control layer.
    Type: Grant
    Filed: April 20, 2018
    Date of Patent: February 8, 2022
    Assignee: TDK CORPORATION
    Inventors: Tatsuo Shibata, Masashi Sahashi, Tomohiro Nozaki
  • Publication number: 20200194157
    Abstract: A magnetization control element according to an aspect of the invention includes a magnetization control layer containing a magnetoelectric material exhibiting a magnetoelectric effect, and a magnetic coupling layer that is magnetically coupled to a magnetization of a first surface of the magnetization control layer through exchange coupling and exhibits a magnetic state according to the magnetization of the first surface, wherein a magnetization having a component in a direction opposite to a direction of a magnetization of the magnetic coupling layer is imparted to the magnetization control layer.
    Type: Application
    Filed: April 20, 2018
    Publication date: June 18, 2020
    Applicant: TDK CORPORATION
    Inventors: Tatsuo SHIBATA, Masashi SAHASHI, Tomohiro NOZAKI
  • Patent number: 9520175
    Abstract: A magnetization controlling element includes a ferromagnetic material layer, an exchange coupling adjustment layer, an antiferromagnetic material layer, an electrode layer, a magnetic field applying mechanism which applies a magnetic field to the antiferromagnetic material layer, and an electric field applying mechanism which applies an electric field to the antiferromagnetic material layer. The antiferromagnetic material layer contains an antiferromagnetic material or ferrimagnetic material having a magnetoelectric effect, the ferromagnetic material layer includes a perpendicular magnetization film having a magnetization component perpendicular to the film surface, the ferromagnetic material layer includes a ferromagnetic material layer that is magnetically connected, through exchange coupling, to the antiferromagnetic material layer. The exchange coupling adjustment layer has a function of adjusting exchange coupling between the ferromagnetic material layer and the antiferromagnetic material layer.
    Type: Grant
    Filed: November 4, 2014
    Date of Patent: December 13, 2016
    Assignee: TDK Corporation
    Inventors: Tatsuo Shibata, Masashi Sahashi
  • Publication number: 20150123755
    Abstract: A magnetization controlling element includes a ferromagnetic material layer, an exchange coupling adjustment layer, an antiferromagnetic material layer, an electrode layer, a magnetic field applying mechanism which applies a magnetic field to the antiferromagnetic material layer, and an electric field applying mechanism which applies an electric field to the antiferromagnetic material layer. The antiferromagnetic material layer contains an antiferromagnetic material or ferrimagnetic material having a magnetoelectric effect, the ferromagnetic material layer includes a perpendicular magnetization film having a magnetization component perpendicular to the film surface, the ferromagnetic material layer includes a ferromagnetic material layer that is magnetically connected, through exchange coupling, to the antiferromagnetic material layer. The exchange coupling adjustment layer has a function of adjusting exchange coupling between the ferromagnetic material layer and the antiferromagnetic material layer.
    Type: Application
    Filed: November 4, 2014
    Publication date: May 7, 2015
    Inventors: Tatsuo SHIBATA, Masashi SAHASHI
  • Patent number: 8929035
    Abstract: A magnetoresistance effect element having a magnetoresistance effect film and a pair of electrode, the magnetoresistance effect film having a first magnetic layer whose direction of magnetization is substantially pinned in one direction, a second magnetization layer whose direction of magnetization changes in response to an external magnetic field, a nonmagnetic intermediate layer located between the first and second magnetic layers, and a film provided in the first magnetic layer, in the second magnetic layer, at an interface between the first magnetic layer and the nonmagnetic intermediate layer, and/or at an interface between the second magnetic layer and the nonmagnetic intermediate layer.
    Type: Grant
    Filed: May 19, 2009
    Date of Patent: January 6, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hiromi Fuke, Hitoshi Iwasaki, Masashi Sahashi
  • Patent number: 8724434
    Abstract: A magnetic recording system including follows: a recording head, a recording medium that includes a first recording medium layer, a second recording medium layer, and a substrate. The magnetic recording system includes an electric field applying device applying an electric field and a magnetic field applying device applying a magnetic field to the recording medium, a movement mechanism that moves them to an arbitrary position. The magnetic recording system has a function of controlling an applying direction of at least one of the electric field applying device and the magnetic field applying device, and the recording head is arranged at a position facing the recording medium.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: May 13, 2014
    Assignee: TDK Corporation
    Inventors: Mikio Matsuzaki, Koichi Shinohara, Tatsuo Shibata, Masashi Sahashi, Tomohiro Nozaki
  • Publication number: 20130279309
    Abstract: A magnetic recording system including follows: a recording head, a recording medium that includes a first recording medium layer, a second recording medium layer, and a substrate. The magnetic recording system includes an electric field applying device applying an electric field and a magnetic field applying device applying a magnetic field to the recording medium, a movement mechanism that moves them to an arbitrary position. The magnetic recording system has a function of controlling an applying direction of at least one of the electric field applying device and the magnetic field applying device, and the recording head is arranged at a position facing the recording medium.
    Type: Application
    Filed: March 15, 2013
    Publication date: October 24, 2013
    Inventors: Mikio MATSUZAKI, Koichi Shinohara, Tatsuo Shibata, Masashi Sahashi, Tomohiro Nozaki
  • Patent number: 8259419
    Abstract: There are provided a magnetoresistance effect element, a magnetic head, a magnetic head assembly and a magnetic recording system, which have high sensitivity and high reliability. The magnetoresistance effect element has two ferromagnetic layers, a non-magnetic layer provided between the ferromagnetic layers, and a layer containing an oxide or nitride as a principal component, wherein the layer containing the oxide or nitride as the principal component contains a magnetic transition metal element which does not bond to oxygen and nitrogen and which is at least one of Co, Fe and Ni.
    Type: Grant
    Filed: September 23, 2011
    Date of Patent: September 4, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Katsuhiko Koi, Hiromi Fuke, Hiroshi Tomita, Hitoshi Iwasaki, Masashi Sahashi
  • Publication number: 20120009440
    Abstract: There are provided a magnetoresistance effect element, a magnetic head, a magnetic head assembly and a magnetic recording system, which have high sensitivity and high reliability. The magnetoresistance effect element has two ferromagnetic layers, a non-magnetic layer provided between the ferromagnetic layers, and a layer containing an oxide or nitride as a principal component, wherein the layer containing the oxide or nitride as the principal component contains a magnetic transition metal element which does not bond to oxygen and nitrogen and which is at least one of Co, Fe and Ni.
    Type: Application
    Filed: September 23, 2011
    Publication date: January 12, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hideaki FUKUZAWA, Katsuhiko KOI, Hiromi FUKE, Hiroshi TOMITA, Hitoshi IWASAKI, Masashi SAHASHI
  • Patent number: 8085511
    Abstract: A magnetoresistance effect element includes a magnetoresistance effect film including a magnetically pinned layer having a magnetic material film whose direction of magnetization is pinned substantially in one direction, a magnetically free layer having a magnetic material film whose direction of magnetization changes in response to an external magnetic field, and a nonmagnetic metal intermediate layer located between said pinned layer and said free layer. The element also includes a pair of electrodes electrically connected to the magnetoresistance effect film to supply a sense current perpendicularly to a film plane of the magnetoresistance effect film. At least one of the pinned layer and the free layer may include a thin-film insertion layer.
    Type: Grant
    Filed: September 23, 2008
    Date of Patent: December 27, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Yuasa, Yuzo Kamiguchi, Masatoshi Yoshikawa, Katsuhiko Koui, Hitoshi Iwasaki, Tomohiko Nagata, Takeo Sakakubo, Masashi Sahashi
  • Patent number: 8049999
    Abstract: There are provided a magnetoresistance effect element, a magnetic head, a magnetic head assembly and a magnetic recording system, which have high sensitivity and high reliability. The magnetoresistance effect element has two ferromagnetic layers, a non-magnetic layer provided between the ferromagnetic layers, and a layer containing an oxide or nitride as a principal component, wherein the layer containing the oxide or nitride as the principal component contains a magnetic transition metal element which does not bond to oxygen and nitrogen and which is at least one of Co, Fe and Ni.
    Type: Grant
    Filed: December 31, 2008
    Date of Patent: November 1, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Katsuhiko Koi, Hiromi Fuke, Hiroshi Tomita, Hitoshi Iwasaki, Masashi Sahashi
  • Patent number: 7897274
    Abstract: A magnetoresistive device includes a magnetization pinned layer, a magnetization free layer, a nonmagnetic intermediate layer formed between the magnetization pinned layer and the magnetization free layer, and electrodes allowing a sense current to flow in a direction substantially perpendicular to the plane of the stack including the magnetization pinned layer, the nonmagnetic intermediate layer and the magnetization free layer. At least one of the magnetization pinned layer and the magnetization free layer is substantially formed of a binary or ternary alloy represented by the formula FeaCobNic (where a+b+c=100 at %, and a?75 at %, b?75 at %, and c?63 at %), or formed of an alloy having a body-centered cubic crystal structure.
    Type: Grant
    Filed: March 13, 2007
    Date of Patent: March 1, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Yuasa, Masatoshi Yoshikawa, Yuzo Kamiguchi, Hitoshi Iwasaki, Masashi Sahashi
  • Patent number: 7898774
    Abstract: A spin valve type magnetoresistive effect element for vertical electric conduction includes a magnetoresistive effect film in which a resistance adjustment layer made of a material containing conductive carriers not more than 1022/cm3 is inserted. Thus the resistance value of a portion in change of spin-relied conduction is raised to an adequate value, thereby to increase the resistance variable amount.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: March 1, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Yuasa, Masatoshi Yoshikawa, Katsuhiko Koui, Hitoshi Iwasaki, Masashi Sahashi
  • Patent number: 7843669
    Abstract: A magnetoresistance effect element comprises a magnetoresistance effect film and a pair of electrode. The magnetoresistance effect film having a first magnetic layer whose direction of magnetization is substantially pinned in one direction; a second magnetic layer whose direction of magnetization changes in response to an external magnetic field; a nonmagnetic intermediate layer located between the first and second magnetic layers; and a film provided in the first magnetic layer, in the second magnetic layer, at a interface between the first magnetic layer and the nonmagnetic intermediate layer, and/or at a interface between the second magnetic layer and the nonmagnetic intermediate layer, the film having a thickness not larger than 3 nanometers, and the film has as least one selected from the group consisting of nitride, oxinitride, phosphide, and fluoride.
    Type: Grant
    Filed: February 6, 2009
    Date of Patent: November 30, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hiromi Fuke, Hitoshi Iwasaki, Masashi Sahashi
  • Patent number: 7791843
    Abstract: There is provided a practical magnetoresistance effect element which has an appropriate value of resistance, which can be sensitized and which has a small number of magnetic layers to be controlled, and a magnetic head and magnetic recording and/or reproducing system using the same. In a magnetoresistance effect element wherein a sense current is caused to flow in a direction perpendicular to the plane of the film, a resistance regulating layer is provided in at least one of a pinned layer, a free layer and an non-magnetic intermediate layer. The resistance regulating layer contains, as a principal component, an oxide, a nitride, a fluoride, a carbide or a boride. The resistance regulating layer may be a continuous film or may have pin holes. Thus, it is possible to provide a practical magnetoresistance effect element which has an appropriate value of resistance, which can be sensitized and which has a small number of magnetic layers, while effectively utilizing the scattering effect depending on spin.
    Type: Grant
    Filed: July 6, 2009
    Date of Patent: September 7, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yuuzo Kamiguchi, Hiromi Yuasa, Tomohiko Nagata, Hiroaki Yoda, Katsuhiko Koui, Masatoshi Yoshikawa, Hitoshi Iwasaki, Masashi Sahashi, Masayuki Takagishi
  • Patent number: 7738220
    Abstract: A magnetoresistance effect element, comprising a nonmagnetic spacer layer, first and second ferromagnetic layers separated by the nonmagnetic spacer layer, the first ferromagnetic layer having a magnetization direction at an angle relative to a magnetization direction of the second ferromagnetic layer at zero applied magnetic field, the magnetization of the first ferromagnetic layer freely rotating in a magnetic field signal, a magnetoresistance effect-improving layer comprising a plurality of metal films and disposed in contact with the first ferromagnetic layer so that the first ferromagnetic layer is disposed between the nonmagnetic spacer layer and the magnetoresistance effect-improving layer, one of the plurality of metal films disposed in contact with the first ferromagnetic layer contains metal element of not solid solution with metal element of the first ferromagnetic layer and a nonmagnetic underlayer or a nonmagnetic protecting layer disposed in contact with the magnetoresistance effect-improving la
    Type: Grant
    Filed: July 17, 2007
    Date of Patent: June 15, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Yuzo Kamiguchi, Katsuhiko Koui, Shin-ichi Nakamura, Hitoshi Iwasaki, Kazuhiro Saito, Hiromi Fuke, Masatoshi Yoshikawa, Susumu Hashimoto, Masashi Sahashi
  • Patent number: 7719800
    Abstract: An example magnetoresistive effect element includes a magnetoresistive effect film including a magnetization pinned layer, a magnetization free layer, and an intermediate layer interposed therebetween and having a magnetic region and a nonmagnetic region whose electrical resistance is higher than the magnetic region. A sense current is passed to the magnetoresistive effect film in a direction substantially perpendicular to the film plane thereof. The magnetic region of the intermediate layer penetrates the nonmagnetic region locally and extends in the direction substantially perpendicular to the film plane. The nonmagnetic region contains a nonmagnetic metallic element having a larger surface energy than a magnetic metallic element contained in the magnetic region.
    Type: Grant
    Filed: December 26, 2006
    Date of Patent: May 18, 2010
    Assignees: Kabuhsiki Kaisha Toshiba, TDK Corporation
    Inventors: Susumu Hashimoto, Hiromi Fuke, Hitoshi Iwasaki, Masaaki Doi, Kousaku Miyake, Masashi Sahashi
  • Publication number: 20090269618
    Abstract: There is provided a practical magnetoresistance effect element which has an appropriate value of resistance, which can be sensitized and which has a small number of magnetic layers to be controlled, and a magnetic head and magnetic recording and/or reproducing system using the same. In a magnetoresistance effect element wherein a sense current is caused to flow in a direction perpendicular to the plane of the film, a resistance regulating layer is provided in at least one of a pinned layer, a free layer and an non-magnetic intermediate layer. The resistance regulating layer contains, as a principal component, an oxide, a nitride, a fluoride, a carbide or a boride. The resistance regulating layer may be a continuous film or may have pin holes. Thus, it is possible to provide a practical magnetoresistance effect element which has an appropriate value of resistance, which can be sensitized and which has a small number of magnetic layers, while effectively utilizing the scattering effect depending on spin.
    Type: Application
    Filed: July 6, 2009
    Publication date: October 29, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yuuzo KAMIGUCHI, Hiromi Yuasa, Tomohiko Nagata, Hiroaki Yoda, Katsuhiko Koui, Masatoshi Yoshikawa, Hitoshi Iwasaki, Masashi Sahashi, Masayuki Takagishi
  • Patent number: 7593195
    Abstract: A magnetoresistance effect element comprises a magnetoresistance effect film and a pair of electrode. The magnetoresistance effect film having a first magnetic layer whose direction of magnetization is substantially pinned in one direction; a second magnetic layer whose direction of magnetization changes in response to an external magnetic field; a nonmagnetic intermediate layer located between the first and second magnetic layers; and a film provided in the first magnetic layer, in the second magnetic layer, at a interface between the first magnetic layer and the nonmagnetic intermediate layer, and/or at a interface between the second magnetic layer and the nonmagnetic intermediate layer, the film having a thickness not larger than 3 nanometers, and the film has as least one selected from the group consisting of nitride, oxinitride, phosphide, and fluoride.
    Type: Grant
    Filed: December 12, 2006
    Date of Patent: September 22, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hiromi Fuke, Hitoshi Iwasaki, Masashi Sahashi
  • Publication number: 20090225477
    Abstract: A magnetoresistance effect element comprises a magnetoresistance effect film and a pair of electrode. The magnetoresistance effect film having a first magnetic layer whose direction of magnetization is substantially pinned in one direction; a second magnetic layer whose direction of magnetization changes in response to an external magnetic field; a nonmagnetic intermediate layer located between the first and second magnetic layers; and a film provided in the first magnetic layer, in the second magnetic layer, at a interface between the first magnetic layer and the nonmagnetic intermediate layer, and/or at a interface between the second magnetic layer and the nonmagnetic intermediate layer, the film having a thickness not larger than 3 nanometers, and the film has as least one selected from the group consisting of oxide, nitride, oxinitride, phosphide, and fluoride.
    Type: Application
    Filed: May 19, 2009
    Publication date: September 10, 2009
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hideaki FUKUZAWA, Hiromi Yuasa, Hiromi Fuke, Hitoshi Iwasaki, Masashi Sahashi