Patents by Inventor Tsutomu Chou

Tsutomu Chou 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).

  • Publication number: 20190206433
    Abstract: A TAMR (thermally assisted magnetic recording) write head uses a gap-based NFT (near-field transducer) to create plasmon near field energy. In one embodiment the NFT is a double ridge aperture structure that simultaneously delivers low transition curvature and better cross-track thermal gradients than previous designs. In another embodiment a NFT comprises a top and bottom ridge not confined to an aperture structure, made of thermo-mechanically stable materials and a parabolic shaped metal layer disposed adjacent to a dielectric waveguide core to couple optical energy to surface plasmon modes.
    Type: Application
    Filed: December 29, 2017
    Publication date: July 4, 2019
    Inventors: Matteo Staffaroni, Koji Shimazawa, Tobias Maletzky, Xuhui Jin, Yoshihiro Tsuchiya, Tsutomu Chou
  • Patent number: 10332553
    Abstract: A TAMR (thermally assisted magnetic recording) write head uses a gap-based NFT (near-field transducer) to create plasmon near field energy. In one embodiment the NFT is a double ridge aperture structure that simultaneously delivers low transition curvature and better cross-track thermal gradients than previous designs. In another embodiment a NFT comprises a top and bottom ridge not confined to an aperture structure, made of thermo-mechanically stable materials and a parabolic shaped metal layer disposed adjacent to a dielectric waveguide core to couple optical energy to surface plasmon modes.
    Type: Grant
    Filed: December 29, 2017
    Date of Patent: June 25, 2019
    Assignee: Headway Technologies, Inc.
    Inventors: Matteo Staffaroni, Koji Shimazawa, Tobias Maletzky, Xuhui Jin, Yoshihiro Tsuchiya, Tsutomu Chou
  • Patent number: 10152991
    Abstract: A method for manufacturing a TAMR (thermal assisted magnetic recording) write head. The write head has a metal blocker formed against a distal end of a waveguide. The waveguide focuses optical radiation on an adjacent plasmon generator where it excites plasmon modes that heat the recording medium. Although the plasmon generator typically heats the recording medium using the plasmon near field to supply the required Joule heating, an unblocked waveguide would also send optical radiation to the medium and surrounding structures producing unwanted heating and device unreliability. The role of the blocker is to block the unwanted optical radiation and, thereby, to limit the heating to that supplied by the plasmon near field.
    Type: Grant
    Filed: December 11, 2017
    Date of Patent: December 11, 2018
    Assignee: Headway Technologies, Inc.
    Inventors: Tsutomu Chou, Kouji Shimazawa, Tobias Maletzky, Weihao Xu, Shinji Hara, Yoshihiro Tsuchiya, Yiming Wang, Cherng-Chyi Han, Xuhui Jin
  • Patent number: 10043542
    Abstract: A plasmon generator generates surface plasmon and generates near-field light from the surface plasmon at a distal end surface situated on an air bearing surface facing a magnetic recording medium. The plasmon generator has a first portion including the distal end surface, a second portion situated away from the air bearing surface, and a separating layer situated between the first portion and the second portion and separating the first portion from the second portion.
    Type: Grant
    Filed: March 25, 2016
    Date of Patent: August 7, 2018
    Assignee: TDK Corporation
    Inventors: Koji Shimazawa, Tsutomu Chou, Yoshihiro Tsuchiya, Kosuke Tanaka
  • Patent number: 10020193
    Abstract: A laser annealing method that includes forming a second layer having through holes on a first layer, and radiating laser light with a wavelength of 3 ?m or greater to the first layer via the through holes.
    Type: Grant
    Filed: June 10, 2016
    Date of Patent: July 10, 2018
    Assignee: TDK Corporation
    Inventors: Koji Shimazawa, Tsutomu Chou
  • Publication number: 20180182419
    Abstract: A TAMR (thermal assisted magnetic recording) write head and a method of its fabrication. The write head has a metal blocker formed against a distal end of a waveguide. The waveguide focuses optical radiation on an adjacent plasmon generator where it excites plasmon modes that heat the recording medium. Although the plasmon generator typically heats the recording medium using the plasmon near field to supply the required Joule heating, an unblocked waveguide would also send optical radiation to the medium and surrounding structures producing unwanted heating and device unreliability. The role of the blocker is to block the unwanted optical radiation and, thereby, to limit the heating to that supplied by the plasmon near field.
    Type: Application
    Filed: December 11, 2017
    Publication date: June 28, 2018
    Inventors: Tsutomu Chou, Kouji Shimazawa, Tobias Maletzky, Weihao Xu, Shinji Hara, Yoshihiro Tsuchiya, Yiming Wang, Cherng-Chyi Han, Xuhui Jin
  • Patent number: 9852752
    Abstract: A TAMR (thermal assisted magnetic recording) write head has a metal blocker formed against a distal end of a waveguide. The waveguide focuses optical radiation on an adjacent plasmon generator where it excites plasmon modes that heat the recording medium. Although the plasmon generator typically heats the recording medium using the plasmon near field to supply the required Joule heating, an unblocked waveguide would also send optical radiation to the medium and surrounding structures producing unwanted heating and device unreliability. The role of the blocker is to block the unwanted optical radiation and, thereby, to limit the heating to that supplied by the plasmon near field.
    Type: Grant
    Filed: August 12, 2016
    Date of Patent: December 26, 2017
    Assignee: Headway Technologies, Inc.
    Inventors: Tsutomu Chou, Kouji Shimazawa, Tobias Maletzky, Weihao Xu, Shinji Hara, Yoshihiro Tsuchiya, Yiming Wang, Cherng-Chyi Han, Xuhui Jin
  • Publication number: 20170278530
    Abstract: A plasmon generator generates surface plasmon and generates near-field light from the surface plasmon at a distal end surface situated on an air bearing surface facing a magnetic recording medium. The plasmon generator has a first portion including the distal end surface, a second portion situated away from the air bearing surface, and a separating layer situated between the first portion and the second portion and separating the first portion from the second portion.
    Type: Application
    Filed: March 25, 2016
    Publication date: September 28, 2017
    Inventors: Koji SHIMAZAWA, Tsutomu CHOU, Yoshihiro TSUCHIYA, Kosuke TANAKA
  • Patent number: 9305573
    Abstract: A thermally assisted magnetic recording head includes core that propagates laser light as propagation light, a near-field light generator that faces a portion of the core and extends to an air bearing surface (ABS), the near-field light generator coupled to the propagation light propagating through the core so as to generate a surface plasmon, propagating the surface plasmon to an end part facing the ABS, and generating near-field light at the end part to irradiate the near-field light to a magnetic recording medium, a main magnetic pole layer provided in the vicinity of the near-field light generator where an end part is positioned on the ABS, a laser diode that generates laser light of wavelength 890 nm to 1,000 nm and enters the laser light into the core, and a photodiode provided on a silicon substrate measures an intensity of the laser light entering from the laser diode to the core.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: April 5, 2016
    Assignee: TDK Corporation
    Inventors: Shinji Hara, Tsutomu Chou, Koji Shimazawa, Eiji Komura, Seiichi Takayama, Yasuhiro Ito
  • Patent number: 9165569
    Abstract: Thermally-assisted magnetic recording head, includes: a magnetic pole having an end exposed on an air-bearing surface; a waveguide; a plasmon generator having a first and second region, first region extending backward from the air-bearing surface to a first position, second region being coupled with the first region at the first position, extending backward from first position, and having a width in a track-width direction, and width in the track-width direction of second region being larger than a width in the track-width direction of first region; an adhesion layer having an end exposed on the air-bearing surface and a first adhesion region, the first adhesion region being in close contact with an end face in the track-width direction of first region; and a cladding layer located around plasmon generator and adhesion layer. Adhesion force between adhesion layer and plasmon generator is greater than adhesion force between cladding layer and plasmon generator.
    Type: Grant
    Filed: May 13, 2014
    Date of Patent: October 20, 2015
    Assignee: TDK CORPORATION
    Inventors: Takafumi Kobayashi, Susumu Aoki, Kosuke Tanaka, Tsutomu Chou, Koji Shimazawa
  • Patent number: 9165581
    Abstract: A thermally assisted magnetic recording head has a generator end surface facing an air bearing surface (ABS), and includes: a near-field light (NF light) generator that generates an NF light on the generator end surface and irradiates a magnetic recording medium with the NF light, and a main magnetic pole end surface positioned in the vicinity of the generator end surface; a main magnetic pole that emits a magnetic flux from the main magnetic pole end surface to the magnetic recording medium and a shield end surface positioned in the vicinity of the generator end surface; and a return shield that is magnetically linked to the main magnetic pole, and that absorbs the magnetic flux returning from the magnetic recording medium at the shield end surface.
    Type: Grant
    Filed: March 11, 2014
    Date of Patent: October 20, 2015
    Assignee: TDK Corporation
    Inventors: Susumu Aoki, Takafumi Kobayashi, Kei Hirata, Eiji Komura, Tsutomu Chou
  • Publication number: 20150262595
    Abstract: A thermally assisted magnetic recording head has a generator end surface facing an air bearing surface (ABS), and includes: a near-field light (NF light) generator that generates an NF light on the generator end surface and irradiates a magnetic recording medium with the NF light, and a main magnetic pole end surface positioned in the vicinity of the generator end surface; a main magnetic pole that emits a magnetic flux from the main magnetic pole end surface to the magnetic recording medium and a shield end surface positioned in the vicinity of the generator end surface; and a return shield that is magnetically linked to the main magnetic pole, and that absorbs the magnetic flux returning from the magnetic recording medium at the shield end surface.
    Type: Application
    Filed: March 11, 2014
    Publication date: September 17, 2015
    Applicant: TDK Corporation
    Inventors: Susumu AOKI, Takafumi KOBAYASHI, Kei HIRATA, Eiji KOMURA, Tsutomu CHOU
  • Patent number: 8970995
    Abstract: A thin film magnetic head includes a magnetoresistive effect (MR) laminated body that has the following structure: first and second magnetic layers in which the magnetization direction of at least one of the magnetic layers changes according to an external magnetic field; the first magnetic layer is provided at a lower side of a laminated direction; the second magnetic layer is provided at an upper side of the laminated direction; a non-magnetic intermediate layer made of ZnO sandwiched between the first and the second magnetic layers; a first intermediate interface layer is provided at the interface between the first magnetic layer and the non-magnetic intermediate layer; and a second intermediate interface layer is provided at the interface between the non-magnetic intermediate layer and the second magnetic layer. At least the first intermediate interface layer contains Ag and Zn, or Au and Zn.
    Type: Grant
    Filed: March 10, 2009
    Date of Patent: March 3, 2015
    Assignee: TDK Corporation
    Inventors: Tsutomu Chou, Shinji Hara, Yoshihiro Tsuchiya, Hironobu Matsuzawa
  • Patent number: 8873351
    Abstract: A thermally assisted magnetic recording head includes a plasmon-generator that generates near-field light (NF light) from a near-field light generating portion on a near field light generator end surface constituting a portion of the medium opposing surface. The plasmon-generator has a first PG part having the near field light generator end surface constituting a portion of the medium opposing surface, and a second PG part positioned at a back side compared to the medium opposing surface when viewed from the medium opposing surface side. When viewed from the medium opposing surface side, the first PG part extends toward the back side from the medium opposing surface, and the second PG part is placed to contact at least a portion of both side surfaces of the first PG part.
    Type: Grant
    Filed: August 28, 2013
    Date of Patent: October 28, 2014
    Assignee: TDK Corporation
    Inventors: Susumu Aoki, Kosuke Tanaka, Shinji Hara, Tsutomu Chou
  • Patent number: 8854931
    Abstract: A polarization converter of the invention includes a core part that wave-guides an electromagnetic wave and a cladding part that is provided around the core part. The core part includes a conversion part converting a polarization state of the electromagnetic wave. A cross-sectional shape of the conversion part in a plane orthogonal to a propagation direction of the electromagnetic wave is a shape formed by cutting off a portion of a rectangular or square shape along a jagged diagonal line.
    Type: Grant
    Filed: March 8, 2013
    Date of Patent: October 7, 2014
    Assignee: TDK Corporation
    Inventors: Eiji Komura, Tsutomu Chou, Koji Shimazawa
  • Patent number: 8845867
    Abstract: A method of manufacturing a magnetoresistive (MR) effective element having a pair of magnetic layers and a nonmagnetic intermediate layer including a ZnO film, wherein a relative angle of magnetization directions of the pair of magnetic layers varies according to an external magnetic field. The method includes a step for introducing a mix gas of oxygen gas and argon gas into a depressurized chamber, wherein a first target of ZnO, a second target of Zn and a substrate having a right-below layer are disposed in the chamber, and a step for depositing the ZnO film on the right-below layer by applying each of a first and second direct current (DC) application power to spaces between the first and second targets and the substrate respectively after the mix gas introducing step, wherein the first and second targets are set at negative potential, and the substrate is set at positive potential.
    Type: Grant
    Filed: December 9, 2008
    Date of Patent: September 30, 2014
    Assignee: TDK Corporation
    Inventors: Shinji Hara, Yoshihiro Tsuchiya, Tsutomu Chou, Tomihito Mizuno
  • Publication number: 20140269233
    Abstract: A thermally assisted magnetic recording head includes core that propagates laser light as propagation light, a near-field light generator that faces a portion of the core and extends to an air bearing surface (ABS), the near-field light generator coupled to the propagation light propagating through the core so as to generate a surface plasmon, propagating the surface plasmon to an end part facing the ABS, and generating near-field light at the end part to irradiate the near-field light to a magnetic recording medium, a main magnetic pole layer provided in the vicinity of the near-field light generator where an end part is positioned on the ABS, a laser diode that generates laser light of wavelength 890 nm to 1,000 nm and enters the laser light into the core, and a photodiode provided on a silicon substrate measures an intensity of the laser light entering from the laser diode to the core.
    Type: Application
    Filed: March 14, 2013
    Publication date: September 18, 2014
    Inventors: Shinji HARA, Tsutomu CHOU, Koji SHIMAZAWA, Eiji KOMURA, Seiichi TAKAYAMA, Yasuhiro ITO
  • Publication number: 20140254333
    Abstract: A polarization converter of the invention includes a core part that wave-guides an electromagnetic wave and a cladding part that is provided around the core part. The core part includes a conversion part converting a polarization state of the electromagnetic wave. A cross-sectional shape of the conversion part in a plane orthogonal to a propagation direction of the electromagnetic wave is a shape formed by cutting off a portion of a rectangular or square shape along a jagged diagonal line.
    Type: Application
    Filed: March 8, 2013
    Publication date: September 11, 2014
    Applicant: TDK Corporation
    Inventors: Eiji KOMURA, Tsutomu CHOU, Koji SHIMAZAWA
  • Patent number: 8760979
    Abstract: The thermally-assisted magnetic recording head includes: a magnetic pole having an end exposed on an air-bearing surface; a waveguide; a plasmon generator provided between the magnetic pole and the waveguide, and having a first region and a second region, the first region extending backward from the air-bearing surface to a first position, and the second region being coupled with the first region at the first position and extending backward from the first position; a gap layer provided between the magnetic pole and the first region of the plasmon generator and extending backward from the air-bearing surface to the first position, and being formed of a dielectric material; and a metallic layer buried in the gap layer, and extending forward from a second position that is located between the air-bearing surface and the first position.
    Type: Grant
    Filed: February 26, 2013
    Date of Patent: June 24, 2014
    Assignee: TDK Corporation
    Inventors: Tsutomu Chou, Eijii Komura, Shinji Hara, Daisuke Miyauchi, Koji Shimazawa, Mitsuo Otsuki
  • Patent number: 8750082
    Abstract: The thermally-assisted magnetic recording head includes: a magnetic pole having an end exposed on an air bearing surface; a waveguide; a plasmon generator provided between the magnetic pole and the waveguide, and having a first region and a second region, the first region extending backward from the air bearing surface to a first position, and the second region being coupled with the first region at the first position and extending backward from the first position; and a gap layer provided between the magnetic pole and the first region of the plasmon generator and extending backward from the air bearing surface, the gap layer including at least two dielectric layers and at least one metallic layer provided between the dielectric layers.
    Type: Grant
    Filed: February 21, 2013
    Date of Patent: June 10, 2014
    Assignee: TDK Corporation
    Inventors: Koji Shimazawa, Eiji Komura, Tsutomu Chou