Patents by Inventor Koichiro Inomata

Koichiro Inomata 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: 10832719
    Abstract: Disclosed is a perpendicularly magnetized film structure using a highly heat resistant underlayer film on which a cubic or tetragonal perpendicularly magnetized film can grow, comprising a substrate of a cubic single crystal substrate having a (001) plane or a substrate having a cubic oriented film that grows to have the (001) plane; an underlayer formed on the substrate from a thin film of a metal having an hcp structure in which the [0001] direction of the thin metal film forms an angle in the range of 42° to 54° with respect to the <001> direction or the (001) orientation of the substrate; and a perpendicularly magnetized layer located on the metal underlayer and formed from a cubic material selected from a Co-based Heusler alloy and a cobalt-iron (CoFe) alloy having a bcc structure a constituent material, and grown to have the (001) plane.
    Type: Grant
    Filed: December 10, 2018
    Date of Patent: November 10, 2020
    Assignee: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Hiroaki Sukegawa, Zhenchao Wen, Seiji Mitani, Koichiro Inomata, Takao Furubayashi, Jason Paul Hadorn, Tadakatsu Ohkubo, Kazuhiro Hono, Jungwoo Koo
  • Publication number: 20190172486
    Abstract: Disclosed is a perpendicularly magnetized film structure using a highly heat resistant underlayer film on which a cubic or tetragonal perpendicularly magnetized film can grow, comprising a substrate of a cubic single crystal substrate having a (001) plane or a substrate having a cubic oriented film that grows to have the (001) plane; an underlayer formed on the substrate from a thin film of a metal having an hcp structure in which the [0001] direction of the thin metal film forms an angle in the range of 42° to 54° with respect to the <001> direction or the (001) orientation of the substrate; and a perpendicularly magnetized layer located on the metal underlayer and formed from a cubic material selected from a Co-based Heusler alloy and a cobalt-iron (CoFe) alloy having a bcc structure a constituent material, and grown to have the (001) plane.
    Type: Application
    Filed: December 10, 2018
    Publication date: June 6, 2019
    Applicant: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Hiroaki SUKEGAWA, Zhenchao WEN, Seiji MITANI, Koichiro INOMATA, Takao FURUBAYASHI, Jason Paul HADORN, Tadakatsu OHKUBO, Kazuhiro HONO, Jungwoo KOO
  • Patent number: 10199063
    Abstract: Disclosed is a perpendicularly magnetized film structure that uses a highly heat resistant underlayer film on which a cubic or tetragonal perpendicularly magnetized film can grow with high quality, the structure comprising any one substrate (5) of a cubic single crystal substrate having a (001) plane, or a substrate having a cubic oriented film that grows to have the (001) plane; an underlayer (6) formed on the substrate (5) from a thin film of a metal having an hcp structure, such as Ru or Re, in which the [0001] direction of the thin metal film forms an angle in the range of 42° to 54° with respect to the <001> direction or the (001) orientation of the substrate (5); and a perpendicularly magnetized layer (7) located on the metal underlayer (6) and formed from a cubic material selected from the group consisting of a Co-based Heusler alloy, a cobalt-iron (CoFe) alloy having a bcc structure, and the like, as a constituent material, and grown to have the (001) plane.
    Type: Grant
    Filed: March 19, 2015
    Date of Patent: February 5, 2019
    Assignee: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Hiroaki Sukegawa, Zhenchao Wen, Seiji Mitani, Koichiro Inomata, Takao Furubayashi, Jason Paul Hadorn, Tadakatsu Ohkubo, Kazuhiro Hono, Jungwoo Koo
  • Publication number: 20170140784
    Abstract: Disclosed is a perpendicularly magnetized film structure that uses a highly heat resistant underlayer film on which a cubic or tetragonal perpendicularly magnetized film can grow with high quality, the structure comprising any one substrate (5) of a cubic single crystal substrate having a (001) plane, or a substrate having a cubic oriented film that grows to have the (001) plane; an underlayer (6) formed on the substrate (5) from a thin film of a metal having an hcp structure, such as Ru or Re, in which the [0001] direction of the thin metal film forms an angle in the range of 42° to 54° with respect to the <001> direction or the (001) orientation of the substrate (5); and a perpendicularly magnetized layer (7) located on the metal underlayer (6) and formed from a cubic material selected from the group consisting of a Co-based Heusler alloy, a cobalt-iron (CoFe) alloy having a bcc structure, and the like, as a constituent material, and grown to have the (001) plane.
    Type: Application
    Filed: March 19, 2015
    Publication date: May 18, 2017
    Applicant: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Hiroaki SUKEGAWA, Zhenchao WEN, Seiji MITANI, Koichiro INOMATA, Takao FURUBAYASHI, Jason Paul HADORN, Tadakatsu OHKUBO, Kazuhiro HONO, Jungwoo KOO
  • Patent number: 8866243
    Abstract: For the present ferromagnetic tunnel junction structure, employed is a means characterized by using an MgO barrier and using a Co2FeAl full-Heusler alloy for any of the ferromagnetic layers therein. The ferromagnetic tunnel junction structure is characterized in that Co2FeAl includes especially a B2 structure and one of the ferromagnetic layers is formed on a Cr buffer layer. The magnetoresistive element is characterized in that the ferromagnetic tunnel junction structure therein is any of the above-mentioned ferromagnetic tunnel junction structure. Accordingly, a large TMR, especially a TMR over 100% at room temperature can be attained, using Co2FeAl having a smallest ? though not a half-metal.
    Type: Grant
    Filed: May 7, 2010
    Date of Patent: October 21, 2014
    Assignee: National Institute for Materials Science
    Inventors: Koichiro Inomata, Wenhong Wang, Hiroaki Sukegawa
  • Patent number: 8575674
    Abstract: Disclosed is a ferromagnetic tunnel junction structure which is characterized by having a tunnel barrier layer that comprises a non-magnetic material having a spinel structure. The ferromagnetic tunnel junction structure is also characterized in that the non-magnetic material is substantially MgAl2O4. The ferromagnetic tunnel junction is also characterized in that at least one of the ferromagnetic layers comprises a Co-based full Heusler alloy having an L21 or B2 structure. The ferromagnetic tunnel junction structure is also characterized in that the Co-based full Heusler alloy comprises a substance represented by the following formula: Co2FeAlxSi1-x (0?x?1). Also disclosed are a magnetoresistive element and a spintronics device, each of which utilizes the ferromagnetic tunnel junction structure and can achieve a high TMR value, that cannot be achieved by employing conventional tunnel barrier layers other than a MgO barrier.
    Type: Grant
    Filed: April 15, 2010
    Date of Patent: November 5, 2013
    Assignee: National Institute for Materials Science
    Inventors: Hiroaki Sukegawa, Koichiro Inomata, Rong Shan, Masaya Kodzuka, Kazuhiro Hono, Takao Furubayashi, Wenhong Wang
  • Publication number: 20120112299
    Abstract: For the present ferromagnetic tunnel junction structure, employed is a means characterized by using an MgO barrier and using a Co2FeAl full-Heusler alloy for any of the ferromagnetic layers therein. The ferromagnetic tunnel junction structure is characterized in that Co2FeAl includes especially a B2 structure and one of the ferromagnetic layers is formed on a Cr buffer layer. The magnetoresistive element is characterized in that the ferromagnetic tunnel junction structure therein is any of the above-mentioned ferromagnetic tunnel junction structure. Accordingly, a large TMR, especially a TMR over 100% at room temperature can be attained, using Co2FeAl having a smallest ? though not a half-metal.
    Type: Application
    Filed: May 7, 2010
    Publication date: May 10, 2012
    Applicant: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Koichiro Inomata, Wenhong Wang, Hiroaki Sukegawa
  • Publication number: 20120091548
    Abstract: Disclosed is a ferromagnetic tunnel junction structure which is characterized by having a tunnel barrier layer that comprises a non-magnetic material having a spinel structure. The ferromagnetic tunnel junction structure is also characterized in that the non-magnetic material is substantially MgAl2O4. The ferromagnetic tunnel junction is also characterized in that at least one of the ferromagnetic layers comprises a Co-based full Heusler alloy having an L21 or B2 structure. The ferromagnetic tunnel junction structure is also characterized in that the Co-based full Heusler alloy comprises a substance represented by the following formula: Co2FeAlxSi1-x (0?x?1). Also disclosed are a magnetoresistive element and a spintronics device, each of which utilizes the ferromagnetic tunnel junction structure and can achieve a high TMR value, that cannot be achieved by employing conventional tunnel barrier layers other than a MgO barrier.
    Type: Application
    Filed: April 15, 2010
    Publication date: April 19, 2012
    Inventors: Hiroaki Sukegawa, Koichiro Inomata, Rong Shan, Masaya Kodzuka, Kazuhiro Hono, Takao Furubayashi, Wenhong Wang
  • Publication number: 20100207052
    Abstract: A method for producing a magnetic particle forming a magnetic material for absorbing electromagnetic waves comprises the steps of mixing an organometallic complex or a metal salt with a chain polymer and dissolving the mixture in a solvent (step S1); raising the temperature of the mixture to reaction temperature (step S2), carrying out a reaction at the reaction temperature (step S3); and forming the magnetic particle having a structure that the periphery of each fine particle formed from the organometallic complex or the metal salt is surrounded by the chain polymer and recovering the formed magnetic particle after the reaction (step S4). The magnetic particle has a nanogranular structure to become a magnetic material for absorbing electromagnetic waves. Such a magnetic particle is produced by a wet reaction. Thus, a larger amount of magnetic particle can be produced by one reaction.
    Type: Application
    Filed: May 3, 2010
    Publication date: August 19, 2010
    Applicant: SONY CORPORATION
    Inventors: Katsumi Okayama, Kaoru Kobayashi, Koichiro Inomata, Sat shi Sugimoto, Yoshihiro Kato
  • Patent number: 7745004
    Abstract: A method for producing a magnetic particle forming a magnetic material for absorbing electromagnetic waves comprises the steps of mixing an organometallic complex or a metal salt with a chain polymer and dissolving the mixture in a solvent (step S1); raising the temperature of the mixture to reaction temperature (step S2), carrying out a reaction at the reaction temperature (step S3); and forming the magnetic particle having a structure that the periphery of each fine particle formed from the organometallic complex or the metal salt is surrounded by the chain polymer and recovering the formed magnetic particle after the reaction (step S4). The magnetic particle has a nanogranular structure to become a magnetic material for absorbing electromagnetic waves. Such a magnetic particle is produced by a wet reaction. Thus, a larger amount of magnetic particle can be produced by one reaction.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: June 29, 2010
    Assignees: Sony Corporation
    Inventors: Katsumi Okayama, Kaoru Kobayashi, Koichiro Inomata, Satoshi Sugimoto, Yoshihiro Kato
  • Patent number: 7593193
    Abstract: A magnetoresistive element has a ferromagnetic double tunnel junction having a stacked structure of a first antiferromagnetic layer/a first ferromagnetic layer/a first dielectric layer/a second ferromagnetic layer/a second dielectric layer/a third ferromagnetic layer/a second antiferromagnetic layer. The second ferromagnetic layer that is a free layer consists of a Co-based alloy or a three-layered film of a Co-based alloy/a Ni—Fe alloy/a Co-based alloy. A tunnel current is flowed between the first ferromagnetic layer and the third ferromagnetic layer.
    Type: Grant
    Filed: August 30, 2007
    Date of Patent: September 22, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koichiro Inomata, Kentaro Nakajima, Yoshiaki Saito, Masayuki Sagoi, Tatsuya Kishi
  • Publication number: 20090015969
    Abstract: Magnetic thin film having high spin polarizability and a magnetoresistance effect device and a magnetic device using the same, provided with a substrate (2) and Co2MGa1-xAlx thin film (3) formed on the substrate (2), the Co2MGa1-xAlx thin film (3) has a L21 or B2 single phase structure, M of the thin film is either one or two or more of Ti, V, Mo, W, Cr, Mn, and Fe, an average valence electron concentration Z in M is 5.5?Z?7.5, and 0?x?0.7, shows ferromagnetism at room temperature, and can attain high spin polarizability. A buffer layer (4) may be inserted between the substrate (2) and the Co2FexCr1-xAl thin film (3). The tunnel magnetoresistance effect device and the giant magnetoresistance effect device using this magnetic thin film can attain large TMR and GMR at room temperature under the low magnetic field.
    Type: Application
    Filed: February 8, 2005
    Publication date: January 15, 2009
    Applicant: JAPAN SCIENCE AND TECHNOLOGY AGENCY
    Inventors: Ryosuke Kainuma, Koichiro Inomata, Kiyohito Ishida
  • Patent number: 7345852
    Abstract: A magnetoresistive element has a ferromagnetic double tunnel junction having a stacked structure of a first antiferromagnetic layer/a first ferromagnetic layer/a first dielectric layer/a second ferromagnetic layer/a second dielectric layer/a third ferromagnetic layer/a second antiferromagnetic layer. The second ferromagnetic layer that is a free layer consists of a Co-based alloy or a three-layered film of a Co-based alloy/a Ni—Fe alloy/a Co-based alloy. A tunnel current is flowed between the first ferromagnetic layer and the third ferromagnetic layer.
    Type: Grant
    Filed: March 6, 2006
    Date of Patent: March 18, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koichiro Inomata, Kentaro Nakajima, Yoshiaki Saito, Masayuki Sagoi, Tatsuya Kishi
  • Publication number: 20070297101
    Abstract: A magnetoresistive element has a ferromagnetic double tunnel junction having a stacked structure of a first antiferromagnetic layer/a first ferromagnetic layer/a first dielectric layer/a second ferromagnetic layer/a second dielectric layer/a third ferromagnetic layer/a second antiferromagnetic layer. The second ferromagnetic layer that is a free layer consists of a Co-based alloy or a three-layered film of a Co-based alloy/a Ni—Fe alloy/a Co-based alloy. A tunnel current is flowed between the first ferromagnetic layer and the third ferromagnetic layer.
    Type: Application
    Filed: August 30, 2007
    Publication date: December 27, 2007
    Inventors: Koichiro Inomata, Kentaro Nakajima, Yoshiaki Saito, Masayuki Sagoi, Tatsuya Kishi
  • Publication number: 20060146451
    Abstract: A magnetoresistive element has a ferromagnetic double tunnel junction having a stacked structure of a first antiferromagnetic layer/a first ferromagnetic layer/a first dielectric layer/a second ferromagnetic layer/a second dielectric layer/a third ferromagnetic layer/a second antiferromagnetic layer. The second ferromagnetic layer that is a free layer consists of a Co-based alloy or a three-layered film of a Co-based alloy/a Ni—Fe alloy/a Co-based alloy. A tunnel current is flowed between the first ferromagnetic layer and the third ferromagnetic layer.
    Type: Application
    Filed: March 6, 2006
    Publication date: July 6, 2006
    Applicant: KABUSHI KAISHA TOSHIBA
    Inventors: Koichiro Inomata, Kentaro Nakajima, Yoshiaki Saito, Masayuki Sagoi, Tatsuya Kishi
  • Patent number: 7038894
    Abstract: A magnetoresistive element has a ferromagnetic double tunnel junction having a stacked structure of a first antiferromagnetic layer/a first ferromagnetic layer/a first dielectric layer/a second ferromagnetic layer/a second dielectric layer/a third ferromagnetic layer/a second antiferromagnetic layer. The second ferromagnetic layer that is a free layer consists of a Co-based alloy or a three-layered film of a Co-based alloy/a Ni—Fe alloy/a Co-based alloy. A tunnel current is flowed between the first ferromagnetic layer and the third ferromagnetic layer.
    Type: Grant
    Filed: April 21, 2005
    Date of Patent: May 2, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koichiro Inomata, Kentaro Nakajima, Yoshiaki Saito, Masayuki Sagoi, Tatsuya Kishi
  • Publication number: 20060060027
    Abstract: A method for producing a magnetic particle forming a magnetic material for absorbing electromagnetic waves comprises the steps of mixing an organometallic complex or a metal salt with a chain polymer and dissolving the mixture in a solvent (step S1); raising the temperature of the mixture to reaction temperature (step S2), carrying out a reaction at the reaction temperature (step S3); and forming the magnetic particle having a structure that the periphery of each fine particle formed from the organometallic complex or the metal salt is surrounded by the chain polymer and recovering the formed magnetic particle after the reaction (step S4). The magnetic particle has a nanogranular structure to become a magnetic material for absorbing electromagnetic waves. Such a magnetic particle is produced by a wet reaction. Thus, a larger amount of magnetic particle can be produced by one reaction.
    Type: Application
    Filed: October 25, 2005
    Publication date: March 23, 2006
    Inventors: Katsumi Okayama, Kaoru Kobayashi, Koichiro Inomata, Satoshi Sugimoto, Yoshihiro Kato
  • Patent number: 6992155
    Abstract: A method for producing a magnetic particle forming a magnetic material for absorbing electromagnetic waves comprises the steps of mixing an organometallic complex or a metal salt with a chain polymer and dissolving the mixture in a solvent (step S1); raising the temperature of the mixture to reaction temperature (step S2), carrying out a reaction at the reaction temperature (step S3); and forming the magnetic particle having a structure that the periphery of each fine particle formed from the organometallic complex or the metal salt is surrounded by the chain polymer and recovering the formed magnetic particle after the reaction (step S4). The magnetic particle has a nanogranular structure to become a magnetic material for absorbing electromagnetic waves. Such a magnetic particle is produced by a wet reaction. Thus, a larger amount of magnetic particle can be produced by one reaction.
    Type: Grant
    Filed: September 17, 2002
    Date of Patent: January 31, 2006
    Assignees: Sony Corporation
    Inventors: Katsumi Okayama, Kaoru Kobayashi, Koichiro Inomata, Satoshi Sugimoto, Yoshihiro Kato
  • Patent number: 6987653
    Abstract: A magnetoresistive element has a ferromagnetic double tunnel junction having a stacked structure of a first antiferromagnetic layer/a first ferromagnetic layer/a first dielectric layer/a second ferromagnetic layer/a second dielectric layer/a third ferromagnetic layer/a second antiferromagnetic layer. The second ferromagnetic layer that is a free layer consists of a Co-based alloy or a three-layered film of a Co-based alloy/a Ni—Fe alloy/a Co-based alloy. A tunnel current is flowed between the first ferromagnetic layer and the third ferromagnetic layer.
    Type: Grant
    Filed: March 11, 2004
    Date of Patent: January 17, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koichiro Inomata, Kentaro Nakajima, Yoshiaki Saito, Masayuki Sagoi, Tatsuya Kishi
  • Publication number: 20050185347
    Abstract: A magnetoresistive element has a ferromagnetic double tunnel junction having a stacked structure of a first antiferromagnetic layer/a first ferromagnetic layer/a first dielectric layer/a second ferromagnetic layer/a second dielectric layer/a third ferromagnetic layer/a second antiferromagnetic layer. The second ferromagnetic layer that is a free layer consists of a Co-based alloy or a three-layered film of a Co-based alloy/a Ni—Fe alloy/a Co-based alloy. A tunnel current is flowed between the first ferromagnetic layer and the third ferromagnetic layer.
    Type: Application
    Filed: April 21, 2005
    Publication date: August 25, 2005
    Applicant: KABUSHI KAISHA TOSHIBA
    Inventors: Koichiro Inomata, Kentaro Nakajima, Yoshiaki Saito, Masayuki Sagoi, Tatsuya Kishi