Patents by Inventor Takehito Shimatsu

Takehito Shimatsu 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: 20160267934
    Abstract: The purpose of the present invention is to provide a magnetic recording medium including a magnetic recording layer having more excellent magnetic properties and including an L1o type ordered alloy. One constitutional example of the magnetic recording medium includes a substrate, a first seed layer comprising ZnO, a second seed layer comprising MgO, and a magnetic recording layer comprising an ordered alloy, in this order.
    Type: Application
    Filed: August 10, 2015
    Publication date: September 15, 2016
    Inventors: Akira Furuta, Shinji Uchida, Tomohiro Moriya, Hitoshi Nakata, Takehito Shimatsu
  • Publication number: 20160254017
    Abstract: The purpose of the present invention is to provide a magnetic recording medium including a first magnetic recording layer having a large coercive force and a granular structure in which magnetic crystal grains are well separated from each other. The magnetic recording medium of the present invention includes a non-magnetic substrate, a first seed layer, and a first magnetic recording layer formed on the first seed layer, wherein the first seed layer includes Pt, the first magnetic recording layer includes one or more magnetic layers, the magnetic layer in contact with the first seed layer includes Fe, Pt and Ti, and the magnetic layer in contact with the first seed layer has a granular structure consisting of magnetic crystal grains of a L10 type ordered alloy including Fe and Pt, and a non-magnetic grain boundary including Ti.
    Type: Application
    Filed: January 13, 2015
    Publication date: September 1, 2016
    Inventors: Hitoshi Nakata, Takehito Shimatsu
  • Publication number: 20160225394
    Abstract: The present invention provides a magnetic recording layer that has a high magnetic anisotropy constant Ku and a low Curie temperature Tc, as well as a magnetic recording medium that incorporates such a magnetic recording layer. The magnetic recording medium of the present invention includes a nonmagnetic substrate and a magnetic recording layer containing an ordered alloy. The ordered alloy may contain at least one element selected from the group consisting of Fe and Ni; at least one element selected from the group consisting of Pt, Pd, Au, Rh and Ir; and Ru.
    Type: Application
    Filed: April 8, 2016
    Publication date: August 4, 2016
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Tomohiro MORIYA, Hitoshi NAKATA, Hiroto KIKUCHI, Hiroyasu KATAOKA, Akira FURUTA, Takehito SHIMATSU
  • Publication number: 20160190417
    Abstract: A semiconductor device includes an insulating substrate,a semiconductor element disposed on an upper surface of the substrate, a heat dissipation member, and a metal bonding layer that bonds the lower surface of the substrate to the upper surface of the heat dissipation member, and the area of the upper surface of the heat dissipation member is larger than the area of the lower surface of the substrate, and the metal bonding layer contacts the whole of the lower surface of the substrate and has an area larger than the area of the lower surface of the substrate, and the heat conductivity of the metal bonding layer is higher than the heat conductivity of the heat dissipation member.
    Type: Application
    Filed: December 21, 2015
    Publication date: June 30, 2016
    Applicant: NICHIA CORPORATION
    Inventors: Masatsugu ICHIKAWA, Satoshi SHICHIJO, Takehito SHIMATSU
  • Patent number: 9257619
    Abstract: To provide a light-emitting device that is provided with an optical member firmly bonded to a semiconductor light-emitting element and has a high light extraction efficiency, the light-emitting device includes a light-emitting element having a semiconductor layer and an optical member bonded to the light-emitting surface of the light-emitting element with a metal film being interposed therebetween wherein the metal film has a thickness in a film-forming rate conversion not less than 0.05 nm nor more than 2 times of an atomic diameter of the metal atoms forming the metal film.
    Type: Grant
    Filed: June 25, 2014
    Date of Patent: February 9, 2016
    Assignee: NICHIA CORPORATION
    Inventors: Masatsugu Ichikawa, Takehito Shimatsu
  • Publication number: 20150213821
    Abstract: A perpendicular magnetic recording medium includes a non-magnetic substrate; and a magnetic recording layer that includes magnetic crystal grains and a non-magnetic crystal grain boundary that surrounds the magnetic crystal grains, wherein the magnetic crystal grains contain an ordered alloy and the non-magnetic crystal grain boundary contains Ge oxides. The magnetic recording layer may have a granular structure. The magnetic crystal grains may be micronized to be sufficiently ordered and separated, and the perpendicular magnetic recording medium may have a high magnetic anisotropy constant Ku and high coercivity Hc.
    Type: Application
    Filed: April 6, 2015
    Publication date: July 30, 2015
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Takuya ONO, Takehito SHIMATSU
  • Patent number: 9093099
    Abstract: Provided are a perpendicular magnetic recording medium and a method for manufacturing the same, the perpendicular magnetic recording medium including an alloy (FePt, FePd, or CoPt) having a large Ku value with an L10 type ordered structure, and obtained with achievement of controlled crystal orientation and thin film formation without heating. Specifically, in the perpendicular magnetic recording medium, at least a nonmagnetic seed layer, a nonmagnetic underlayer, and a magnetic layer are formed in this order on a nonmagnetic substrate. The nonmagnetic seed layer includes a MgO layer and a metal layer having a body-centered cubic (bcc) structure. The nonmagnetic underlayer has a NaCl type structure of one selected from the group consisting of MgO, NiO, TiO, CrN, Ti carbides, and Ti nitrides. The magnetic layer includes an alloy selected from the group consisting of FePt, FePd, and CoPt having an L10 type ordered structure.
    Type: Grant
    Filed: July 8, 2013
    Date of Patent: July 28, 2015
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Yuki Inaba, Takehito Shimatsu
  • Publication number: 20150132608
    Abstract: A perpendicular magnetic recording medium includes at least a nonmagnetic substrate and a magnetic recording layer. The magnetic recording layer is constituted by a plurality of layers that includes at least a first magnetic recording layer and a second magnetic recording layer. The first magnetic recording layer has a granular structure that includes first magnetic crystal grains and first nonmagnetic crystal grain boundaries surrounding the first magnetic crystal grains. The first magnetic crystal grains include an ordered alloy, and the first nonmagnetic crystal grain boundaries are constituted by carbon. The second magnetic recording layer has a granular structure that includes second magnetic crystal grains and a second nonmagnetic crystal grain boundaries that surround the second magnetic crystal grains. The second magnetic crystal grains include an ordered alloy, and the second nonmagnetic crystal grain boundaries are constituted by a carbon-containing nonmagnetic material.
    Type: Application
    Filed: December 4, 2014
    Publication date: May 14, 2015
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Hiroyasu KATAOKA, Hiroto KIKUCHI, Akira FURUTA, Shinji UCHIDA, Takehito SHIMATSU
  • Publication number: 20150048398
    Abstract: To provide a light-emitting device that is provided with an optical member firmly bonded to a semiconductor light-emitting element and has a high light extraction efficiency, the light-emitting device includes a light-emitting element having a semiconductor layer and an optical member bonded to the light-emitting surface of the light-emitting element with a metal film being interposed therebetween wherein the metal film has a thickness in a film-forming rate conversion not less than 0.05 nm nor more than 2 times of an atomic diameter of the metal atoms forming the metal film.
    Type: Application
    Filed: June 25, 2014
    Publication date: February 19, 2015
    Inventors: Masatsugu Ichikawa, Takehito Shimatsu
  • Patent number: 8691402
    Abstract: A perpendicular magnetic recording medium according to which both the thermal stability of the magnetization is good and writing with a magnetic head is easy, and moreover the SNR is improved. In the case of a perpendicular magnetic recording medium comprising a nonmagnetic substrate (1), and at least a nonmagnetic underlayer (2), a magnetic recording layer (3), and a protective layer (4) formed in this order on the nonmagnetic substrate (1), the magnetic recording layer (3) comprises a low Ku region (31) layer having a perpendicular magnetic anisotropy constant (Ku value) of not more than 1×105 erg/cm3, and a high Ku region (32) layer having a Ku value of at least 1×106 erg/cm3. Moreover, the magnetic recording layer (3) is made to have therein nonmagnetic grain boundaries that contain a nonmagnetic oxide and magnetically isolate crystal grains, which are made of a ferromagnetic metal, from one another.
    Type: Grant
    Filed: November 2, 2012
    Date of Patent: April 8, 2014
    Assignees: Fuji Electric Co., Ltd., National University Corporation Tohoku University
    Inventors: Osamu Kitakami, Yutaka Shimada, Satoshi Okamoto, Takehito Shimatsu, Hajime Aoi, Hiroaki Muraoka, Yoshihisa Nakamura, Hiroyuki Uwazumi, Tadaaki Oikawa
  • Publication number: 20140072829
    Abstract: The present invention provides: a thin film structure including an ordered alloy in which atoms are orderly arranged using an inexpensive substrate; and a method for manufacturing the thin film structure. Specifically, the thin film structure includes a substrate, a plating layer formed on the substrate and made of one selected from the group consisting of NiPMo and NiPW, and an ordered alloy disposed on the plating layer. The method for manufacturing the thin film structure includes the steps of: forming a plating layer on a substrate, the plating layer being made of one selected from the group consisting of NiPMo and NiPW; and forming an ordered alloy on the plating layer. The vacuum degree immediately before the ordered alloy is formed is 7.0×10?7 Pa or less. In the step of forming the ordered alloy, a process gas has an impurity concentration of 5 ppb or lower.
    Type: Application
    Filed: July 8, 2013
    Publication date: March 13, 2014
    Inventors: Yuki INABA, Takehito SHIMATSU
  • Publication number: 20140072828
    Abstract: Provided are a perpendicular magnetic recording medium and a method for manufacturing the same, the perpendicular magnetic recording medium including an alloy (FePt, FePd, or CoPt) having a large Ku value with an L10 type ordered structure, and obtained with achievement of controlled crystal orientation and thin film formation without heating. Specifically, in the perpendicular magnetic recording medium, at least a nonmagnetic seed layer, a nonmagnetic underlayer, and a magnetic layer are formed in this order on a nonmagnetic substrate. The nonmagnetic seed layer includes a MgO layer and a metal layer having a body-centered cubic (bcc) structure. The nonmagnetic underlayer has a NaCl type structure of one selected from the group consisting of MgO, NiO, TiO, CrN, Ti carbides, and Ti nitrides. The magnetic layer includes an alloy selected from the group consisting of FePt, FePd, and CoPt having an L10 type ordered structure.
    Type: Application
    Filed: July 8, 2013
    Publication date: March 13, 2014
    Applicant: Fuji Electric Co., Ltd.
    Inventors: Yuki INABA, Takehito SHIMATSU
  • Patent number: 8323808
    Abstract: There is provided a perpendicular magnetic recording medium according to which both the thermal stability of the magnetization is good and writing with a magnetic head is easy, and moreover the SNR is improved. In the case of a perpendicular magnetic recording medium comprising a nonmagnetic substrate 1, and at least a nonmagnetic underlayer 2, a magnetic recording layer 3 and a protective layer 4 formed in this order on the nonmagnetic substrate 1, the magnetic recording layer 3 comprises a low Ku region 31 layer having a perpendicular magnetic anisotropy constant (Ku value) of not more than 1×105 erg/cm3, and a high Ku region 32 layer having a Ku value of at least 1×106 erg/cm3. Moreover, the magnetic recording layer 3 is made to have therein nonmagnetic grain boundaries that contain a nonmagnetic oxide and magnetically isolate crystal grains, which are made of a ferromagnetic metal, from one another.
    Type: Grant
    Filed: January 10, 2005
    Date of Patent: December 4, 2012
    Assignees: Fuji Electric Co., Ltd., National University Corporation Tohoku University
    Inventors: Osamu Kitakami, Yutaka Shimada, Satoshi Okamoto, Takehito Shimatsu, Hajime Aoi, Hiroaki Muraoka, Yoshihisa Nakamura, Hiroyuki Uwazumi, Tadaaki Oikawa
  • Patent number: 8076012
    Abstract: Disclosed are a magnetic thin film capable of providing a high uniaxial magnetic anisotropy, Ku, while suppressing the saturation magnetization Ms thereof, and a method for forming the film; and also disclosed are various devices to which the magnetic thin film is applied. The magnetic thin film comprises a Co-M-Pt alloy having an L11-type ordered structure (wherein M represents one or more metal elements except Co and Pt). For example, the Co-M-Pt alloy is a Co—Ni—Pt alloy of which the composition comprises from 10 to 35 at. % of Co, from 20 to 55 at. % of Ni and a balance of Pt. The magnetic thin film is applicable to perpendicular magnetic recording media, tunnel magneto-resistance (TMR) devices, magnetoresistive random access memories (MRAM), microelectromechanical system (MEMS) devices, etc.
    Type: Grant
    Filed: July 28, 2009
    Date of Patent: December 13, 2011
    Assignees: Tohoku University, Fuji Electric Co., Ltd.
    Inventors: Takehito Shimatsu, Hideo Sato, Osamu Kitakami, Satoshi Okamoto, Hajime Aoi, Hiroyasu Kataoka
  • Patent number: 7993762
    Abstract: The present invention relates to a magnetic thin film containing a L11 type Co—Pt—C alloy in which atoms are orderly arranged, and can realize an order degree excellent in regard to the L11 type Co—Pt—C alloy to achieve excellent magnetic anisotropy of the magnetic thin film. Therefore, in the various application devices using the magnetic thin film, it is possible to achieve a large capacity process and/or a high density process thereof in a high level.
    Type: Grant
    Filed: December 4, 2009
    Date of Patent: August 9, 2011
    Assignees: Tohoku University, Fuji Electric Device Technology Co., Ltd.
    Inventors: Takehito Shimatsu, Hideo Sato, Osamu Kitakami, Satoshi Okamoto, Hajime Aoi, Hiroyasu Kataoka
  • Publication number: 20110020669
    Abstract: A magnetic recording medium having excellent stability of recorded magnetic signals and capable of recording magnetic signals by a thermally assisted magnetic recording system in which a magnetic recording layer of the magnetic recording medium contains ferromagnetic crystal grains of a Co—Ni—Pt alloy with a Pt content of 44 at % or more and 55 at % or less and with an atom content ratio: Ni/(Co+Ni) of 0.64 or more and 0.8 or less. The magnetic recording medium has extremely excellent stability of recorded magnetic signals since the Co—Ni—Pt alloy constituting the magnetic recording layer has an extremely high anisotropy field at a normal temperature. Further, the magnetic recording medium can perform signal recording based on the thermally assisted magnetic recording system since the Co—Ni—Pt alloy constituting the magnetic recording layer has a Curie point within an appropriate temperature range.
    Type: Application
    Filed: July 21, 2010
    Publication date: January 27, 2011
    Inventors: Junichi SAYAMA, Hiroaki Nemoto, Hiroshi Ide, Hiroyasu Kataoka, Nobuyukl Takahashi, Takehito Shimatsu, Osamu Kitakami, Satoshi Okamoto, Hajime Aoi
  • Publication number: 20100140727
    Abstract: The present invention relates to a magnetic thin film containing a L11 type Co—Pt—C alloy in which atoms are orderly arranged, and can realize an order degree excellent in regard to the L11 type Co—Pt—C alloy to achieve excellent magnetic anisotropy of the magnetic thin film. Therefore, in the various application devices using the magnetic thin film, it is possible to achieve a large capacity process and/or a high density process thereof in a high level.
    Type: Application
    Filed: December 4, 2009
    Publication date: June 10, 2010
    Applicants: Tohoku University, Fuji Electric Device Technology Co., Ltd.
    Inventors: Takehito SHIMATSU, Hideo SATO, Osamu KITAKAMI, Satoshi OKAMOTO, Hajime AOI, Hiroyasu KATAOKA
  • Publication number: 20100055503
    Abstract: Disclosed are a magnetic thin film capable of providing a high uniaxial magnetic anisotropy, Ku, while suppressing the saturation magnetization Ms thereof, and a method for forming the film; and also disclosed are various devices to which the magnetic thin film is applied. The magnetic thin film comprises a Co-M-Pt alloy having an L11-type ordered structure (wherein M represents one or more metal elements except Co and Pt). For example, the Co-M-Pt alloy is a Co—Ni—Pt alloy of which the composition comprises from 10 to 35 at. % of Co, from 20 to 55 at. % of Ni and a balance of Pt. The magnetic thin film is applicable to perpendicular magnetic recording media, tunnel magneto-resistance (TMR) devices, magnetoresistive random access memories (MRAM), microelectromechanical system (MEMS) devices, etc.
    Type: Application
    Filed: July 28, 2009
    Publication date: March 4, 2010
    Applicants: TOHOKU UNIVERSITY, FUJI ELECTRIC DEVICE TECHNOLOGY CO., LTD.
    Inventors: Takehito SHIMATSU, Hideo SATO, Osamu KITAKAMI, Satoshi OKAMOTO, Hajime AOI, Hiroyasu KATAOKA
  • Publication number: 20050181237
    Abstract: There is provided a perpendicular magnetic recording medium according to which both the thermal stability of the magnetization is good and writing with a magnetic head is easy, and moreover the SNR is improved. In the case of a perpendicular magnetic recording medium comprising a nonmagnetic substratel, and at least a nonmagnetic underlayer 2, a magnetic recording layer 3 and a protective layer 4 formed in this order on the nonmagnetic substrate 1, the magnetic recording layer 3 comprises a low Ku region 31 layer having a perpendicular magnetic anisotropy constant (Ku value) of not more than 1×105 erg/cm3, and a high Ku region 32 layer having a Ku value of at least 1×106 erg/cm3. Moreover, the magnetic recording layer 3 is made to have therein nonmagnetic grain boundaries that contain a nonmagnetic oxide and magnetically isolate crystal grains, which are made of a ferromagnetic metal, from one another.
    Type: Application
    Filed: January 10, 2005
    Publication date: August 18, 2005
    Inventors: Osamu Kitakami, Yutaka Shimada, Satoshi Okamoto, Takehito Shimatsu, Hajime Aoi, Hiroaki Muraoka, Yoshihisa Nakamura, Hiroyuki Uwazumi, Tadaaki Oikawa