Patents by Inventor Susumu Soeya

Susumu Soeya 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: 9490428
    Abstract: Technology capable of improving performance of a phase-change memory is provided. A recording/reproducing film contains Sn (tin), Sb (antimony), and Te (tellurium) and also contains an element X having a bonding strength with Te stronger than a bonding strength between Sn and Te and a bonding strength between Sb and Te. Here, the recording/reproducing film has a (SnXSb)Te alloy phase, and this (SnXSb)Te alloy phase includes a self-assembled superlattice structure.
    Type: Grant
    Filed: February 3, 2014
    Date of Patent: November 8, 2016
    Assignee: Hitachi, Ltd.
    Inventors: Susumu Soeya, Toshimichi Shintani, Takahiro Odaka
  • Patent number: 9177640
    Abstract: A phase-change device capable of realizing a multi-level record in a superlattice phase-change memory cell in which a superlattice phase-change material is used as a recording film, and thereby achieving the reduction in power consumption and the capacity increase is provided. To a phase-change memory cell composed of GeTe/Sb2Te3 superlattice or SnTe/Sb2Te3 superlattice, a SET pulse is once applied to form a SET state (low resistance state). Thereafter, recording pulses having respectively different voltage values between a voltage value forming the SET state and a voltage value forming a RESET state (high resistance state) are respectively applied to the superlattice phase-change memory cell twice or more. In this manner, a read resistance (SET resistance) corresponding to a recording pulse (SET pulse) and read resistances corresponding to each of the recording pulses are obtained, so that the multi-level record can be realized.
    Type: Grant
    Filed: January 24, 2014
    Date of Patent: November 3, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Toshimichi Shintani, Susumu Soeya
  • Patent number: 9082970
    Abstract: A phase-change memory and a semiconductor recording reproducing device capable of reducing consumed power are provided. A SnxTe100-x/Sb2Te3 SL film obtained by depositing a SnxTe100-x film and a Sb2Te3 film layer by layer contains a SnTe/Sb2Te3 superlattice phase formed of SnTe and Sb2Te3, a SnSbTe alloy phase, and a Te phase. The SnTe/Sb2Te3 superlattice phase is diluted by the SnSbTe alloy phase and the Te phase. Here, X of the SnxTe100-x film is represented by 4 at. %?X?55 at. %.
    Type: Grant
    Filed: October 10, 2013
    Date of Patent: July 14, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Susumu Soeya, Takahiro Odaka, Toshimichi Shintani, Junji Tominaga
  • Publication number: 20150144865
    Abstract: Technology capable of improving performance of a phase-change memory is provided. A recording/reproducing film contains Sn (tin), Sb (antimony), and Te (tellurium) and also contains an element X having a bonding strength with Te stronger than a bonding strength between Sn and Te and a bonding strength between Sb and Te. Here, the recording/reproducing film has a (SnXSb)Te alloy phase, and this (SnXSb)Te alloy phase includes a self-assembled superlattice structure.
    Type: Application
    Filed: February 3, 2014
    Publication date: May 28, 2015
    Inventors: Susumu Soeya, Toshimichi Shintani, Takahiro Odaka
  • Publication number: 20140376307
    Abstract: A phase-change device capable of realizing a multi-level record in a superlattice phase-change memory cell in which a superlattice phase-change material is used as a recording film, and thereby achieving the reduction in power consumption and the capacity increase is provided. To a phase-change memory cell composed of GeTe/Sb2Te3 superlattice or SnTe/Sb2Te3 superlattice, a SET pulse is once applied to form a SET state (low resistance state). Thereafter, recording pulses having respectively different voltage values between a voltage value forming the SET state and a voltage value forming a RESET state (high resistance state) are respectively applied to the superlattice phase-change memory cell twice or more. In this manner, a read resistance (SET resistance) corresponding to a recording pulse (SET pulse) and read resistances corresponding to each of the recording pulses are obtained, so that the multi-level record can be realized.
    Type: Application
    Filed: January 24, 2014
    Publication date: December 25, 2014
    Inventors: Toshimichi Shintani, Susumu Soeya
  • Publication number: 20140252304
    Abstract: A phase-change memory and a semiconductor recording/reproducing device capable of reducing consumed power are provided. A SnxTe100-x/Sb2Te3 SL film obtained by depositing a SnxTe100-x film and a Sb2Te3 film layer by layer contains a SnTe/Sb2Te3 superlattice phase formed of SnTe and Sb2Te3, a SnSbTe alloy phase, and a Te phase. The SnTe/Sb2Te3 superlattice phase is diluted by the SnSbTe alloy phase and the Te phase. Here, X of the SnxTe100-x film is represented by 4 at. %?X?55 at. %.
    Type: Application
    Filed: October 10, 2013
    Publication date: September 11, 2014
    Applicant: National Institute of Advanced Industrial Science and Technology
    Inventors: Susumu Soeya, Takahiro Odaka, Toshimichi Shintani, Junji Tominaga
  • Patent number: 8084149
    Abstract: Embodiments of the invention provide a thermally assisted magnetic recording medium, which can overcome resistance against thermal fluctuation at RT and write capability, obtain a drastic temperature variation in coercive force at right below the recording temperature, and be formed at low temperature. In one embodiment, the medium has a layered structure formed of a lower high-KF ferromagnetic (F) layer formed on a substrate, satisfying TW<TC, an intermediate low-KAF antiferromagnetic (AF) layer satisfying TB<TW, and an upper ferromagnetic (F) layer for recording and reproducing, satisfying TW<TC, where TW is a recording temperature, TC is a Curie point, TN is a Neel point, TB is a blocking temperature, KF is a ferromagnetic magnetocrystalline anisotropy constant, and KAF is an antiferromagnetic magnetocrystalline anisotropy constant.
    Type: Grant
    Filed: July 25, 2006
    Date of Patent: December 27, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Susumu Soeya
  • Patent number: 7732005
    Abstract: A method for producing a recording medium provides good throughput for mass production and reduces cost. The method facilitates the control of the shape or dimensions of a pattern obtained by microfabrication, allows an accurate pattern transfer, and provides superior uniformity. A magnetic layer is formed on a substrate. A nano-particle film 16 is formed on a desired portion on the magnetic layer. Using the nano-particle film as a mask, the magnetic layer is cut. A micropattern with concavities and convexities is formed on the magnetic layer by removing the nano-particle film.
    Type: Grant
    Filed: May 23, 2005
    Date of Patent: June 8, 2010
    Assignee: Hitachi, Ltd.
    Inventors: Yuko Tsuchiya, Susumu Soeya, Hiromasa Takahashi
  • Publication number: 20080074776
    Abstract: Embodiments of the present invention provide a heat-assisted magnetic recording medium capable of overcoming contradiction between the thermal fluctuation resistance at RT and easy writing at high temperature, capable of making the change of the coercive force to temperature change abrupt just below the recording temperature, and capable of formation at low temperature, specific anisotropy axis orientation and granulation.
    Type: Application
    Filed: August 28, 2007
    Publication date: March 27, 2008
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Susumu Soeya
  • Patent number: 7265948
    Abstract: No related magnetoresistive multi-layered films made from a metal magnetic film provide sufficient reproducing output power. A high-polarized layer with a thickness of 10 nm or less is formed as a Fe-rich Fe—O layer in contact with the interface of a non-magnetic intermediate layer and the resulting layers are heat treated to form a multi-layered film of ferromagnetic Fe—O layers, achieving a magnetoresistive element having high magnetoresistance.
    Type: Grant
    Filed: November 7, 2005
    Date of Patent: September 4, 2007
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.,
    Inventors: Hiroyuki Hoshiya, Susumu Soeya, Kenichi Meguro
  • Publication number: 20070048552
    Abstract: Embodiments of the invention provide a thermally assisted magnetic recording medium, which can overcome resistance against thermal fluctuation at RT and write capability, obtain a drastic temperature variation in coercive force at right below the recording temperature, and be formed at low temperature. In one embodiment, the medium has a layered structure formed of a lower high-KF ferromagnetic (F) layer formed on a substrate, satisfying TW<TC, an intermediate low-KAF antiferromagnetic (AF) layer satisfying TB<TW, and an upper ferromagnetic (F) layer for recording and reproducing, satisfying TW<TC, where TW is a recording temperature, TC is a Curie point, TN is a Neel point, TB is a blocking temperature, KF is a ferromagnetic magnetocrystalline anisotropy constant, and KAF is an antiferromagnetic magnetocrystalline anisotropy constant.
    Type: Application
    Filed: July 25, 2006
    Publication date: March 1, 2007
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Susumu Soeya
  • Publication number: 20060153976
    Abstract: A magnetic recording medium, a hard disk using the same, and a manufacturing method thereof are provided. In one example, the magnetic nano-particle medium is formed by depositing a magnetic nano-particle colloid on a substrate, wherein the axes of easy magnetization of respective crystalline particles are aligned with high accuracy. A layer of L10 alloy nano-particles which will exhibit magnetic properties through an order-disorder transition, and arranged at a substantially uniform spacing on a substrate, and a carbon-containing covering film for surrounding these nano-particles and making the spacing substantially uniform are provided. To the L10 alloy of the nano-particles, at least one non-magnetic element is added, or a covered layer comprising at least one non-magnetic layer is formed therearound.
    Type: Application
    Filed: March 14, 2006
    Publication date: July 13, 2006
    Inventors: Kenchi Ito, Susumu Soeya, Yuko Tsuchiya
  • Patent number: 7072155
    Abstract: A magnetoresistive sensor of the type of flowing a signal sensing current perpendicular to the plane, a magnetic head using the magnetoresistive sensor, and a magnetic disk apparatus, comprising a substrate, a pair of magnetic shield layers consisting of a lower magnetic shield layer and an upper magnetic shield layer, a magnetoresistive sensor layer, disposed between the pair of magnetic shield layers, an electrode terminal for flowing a signal current perpendicular to the plane of the magnetoresistive sensor layer, and magnetic domain control layers for controlling Barkhausen noise of the magnetoresistive sensor layer, the magnetic domain control layers being disposed in contact with opposite ends of the magnetoresistive sensor layer consist of a material having high electric resistivity and with a specific resistance not less than 10 m?cm.
    Type: Grant
    Filed: July 26, 2005
    Date of Patent: July 4, 2006
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Hiromasa Takahashi, Reiko Arai, Susumu Soeya
  • Publication number: 20060061914
    Abstract: No related magnetoresistive multi-layered films made from a metal magnetic film provide sufficient reproducing output power. A high-polarized layer with a thickness of 10 nm or less is formed as a Fe-rich Fe—O layer in contact with the interface of a non-magnetic intermediate layer and the resulting layers are heat treated to form a multi-layered film of ferromagnetic Fe—O layers, achieving a magnetoresistive element having high magnetoresistance.
    Type: Application
    Filed: November 7, 2005
    Publication date: March 23, 2006
    Inventors: Hiroyuki Hoshiya, Susumu Soeya, Kenichi Meguro
  • Publication number: 20050266271
    Abstract: A method for producing a recording medium provides good throughput for mass production and reduces cost. The method facilitates the control of the shape or dimensions of a pattern obtained by microfabrication, allows an accurate pattern transfer, and provides superior uniformity. A magnetic layer is formed on a substrate. A nano-particle film 16 is formed on a desired portion on the magnetic layer. Using the nano-particle film as a mask, the magnetic layer is cut. A micropattern with concavities and convexities is formed on the magnetic layer by removing the nano-particle film.
    Type: Application
    Filed: May 23, 2005
    Publication date: December 1, 2005
    Inventors: Yuko Tsuchiya, Susumu Soeya, Hiromasa Takahashi
  • Publication number: 20050254182
    Abstract: A magnetoresistive sensor of the type of flowing a signal sensing current perpendicular to the plane, a magnetic head using the magnetoresistive sensor, and a magnetic disk apparatus, comprising a substrate, a pair of magnetic shield layers consisting of a lower magnetic shield layer and an upper magnetic shield layer, a magnetoresistive sensor layer, disposed between the pair of magnetic shield layers, an electrode terminal for flowing a signal current perpendicular to the plane of the magnetoresistive sensor layer, and magnetic domain control layers for controlling Barkhausen noise of the magnetoresistive sensor layer, the magnetic domain control layers being disposed in contact with opposite ends of the magnetoresistive sensor layer consist of a material having high electric resistivity and with a specific resistance not less than 10 m?cm.
    Type: Application
    Filed: July 26, 2005
    Publication date: November 17, 2005
    Inventors: Hiromasa Takahashi, Reiko Arai, Susumu Soeya
  • Patent number: 6947316
    Abstract: There are provided a magnetoresistive sensor of the type of flowing a signal sensing current perpendicular to the plane to improve resolution at reproducing a signal, a magnetic head using the magnetoresistive sensor, and a magnetic disk apparatus.
    Type: Grant
    Filed: January 13, 2004
    Date of Patent: September 20, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Hiromasa Takahashi, Reiko Arai, Susumu Soeya
  • Patent number: 6917088
    Abstract: A magneto-resistive device has a high reproducing output and is suitable for use as a CPP-GMR device. The magneto-resistive device has a first magnetic layer, a second magnetic layer, and a non-magnetic spacer formed between the first and second magnetic layers. The first magnetic layer contains a magnetic material whose conduction electrons belong to a first energy band, and the second magnetic layer contains a magnetic material whose conduction electrons belong to a second energy band. The first and second energy bands are attributable to orbitals of the same kind, thereby increasing the ratio of change in magnetoresistance and adjusting the electric resistance.
    Type: Grant
    Filed: December 31, 2002
    Date of Patent: July 12, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Hiromasa Takahashi, Jun Hayakawa, Susumu Soeya, Kenchi Ito
  • Patent number: 6876523
    Abstract: A magnetic head at high sensitivity and with enhanced output having a magnetoresistive element of high output and optimal for use in CPP-GMR, the magnetoresistive element comprising a pinned layer 606 containing a half-metal, a free layer 608 formed on one main surface of the pinned layer 606, a spacer 607 formed between the pinned layer 606 and the free layer 608, an anti-ferromagnetic layer 603 formed on the main surface of the pinned layer 606, a soft magnetic layer 604 formed between the pinned layer 606 and the anti-ferromagnetic layer 606, and a noble-metallic layer 605 formed between the pinned layer 606 and the soft magnetic layer.
    Type: Grant
    Filed: August 22, 2002
    Date of Patent: April 5, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Hiromasa Takahashi, Susumu Soeya, Jun Hayakawa, Kenchi Ito
  • Patent number: 6870718
    Abstract: A magnetoresistive sensor of the type of flowing a signal sensing current perpendicular to the plane to improve resolution at reproducing a signal, a magnetic head using the magnetoresistive sensor, and a magnetic disk apparatus. A magnetoresistive sensor comprising a substrate, a pair of magnetic shield layers consisting of a lower magnetic shield layer and an upper magnetic shield layer, a magnetoresistive sensor layer, disposed between the pair of magnetic shield layers, an electrode terminal for flowing a signal current perpendicular to the plane of the magnetoresistive sensor layer, and magnetic domain control layers for controlling Barkhausen noise of the magnetoresistive sensor layer, wherein the magnetic domain control layers disposed in contact with opposite ends of the magnetoresistive sensor layer consist of a material having high electric resistivity and with a specific resistance not less than 10 m?cm so as to give the magnetoresistive sensor having excellent reproducing resolution.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: March 22, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Hiromasa Takahashi, Reiko Arai, Susumu Soeya