Patents by Inventor Tomohito Mizuno

Tomohito Mizuno 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: 20100022014
    Abstract: A method for efficiently evaluating or selecting an obesity controlling substance, a blood insulin regulating substance or a blood sugar regulating substance, is provided. A method for evaluating or screening an obesity controller, the method including administering a carbohydrate and a lipid to an animal, and evaluating or selecting a substance which decreases or increases insulin secretion, is also provided.
    Type: Application
    Filed: November 7, 2007
    Publication date: January 28, 2010
    Applicant: Kao Corporation
    Inventors: Akira Shimotoyodome, Junko Suzuki, Nanami Takeno, Daisuke Fukuoka, Tomohito Mizuno, Shinichi Meguro
  • Publication number: 20090303640
    Abstract: A magneto resistance effect element includes a first magnetic layer, a second magnetic layer and a spacer layer interposed between the first and second magnetic layers. The magneto resistance effect element is configured to allow sense current to flow in a direction that is perpendicular to film planes of the first magnetic layer, the second magnetic layer and the spacer layer so that a relative angle between a magnetization direction of the first magnetic layer and a magnetization direction of the second magnetic layer varies depending on an external magnetic field. The present invention aims at providing a magneto resistance effect element which ensures high resistance to sense current, while limiting the influence of the current limiting layer on the magnetic layer, and which thereby achieves a high magneto resistance ratio.
    Type: Application
    Filed: April 25, 2008
    Publication date: December 10, 2009
    Applicant: TDK CORPORATION
    Inventors: Tomohito Mizuno, Koji Shimazawa, Yoshihiro Tsuchiya, Daisuke Miyauchi, Takahiko Machita, Shinji Hara, Tsutomu Chou, Hironobu Matsuzawa, Toshiyuki Ayukawa, Tsuyoshi Ichiki
  • Publication number: 20090296283
    Abstract: The invention provides a magnetoresistive device of the CPP (current perpendicular to plane) structure, comprising a magnetoresistive unit, and a first shield layer and a second shield layer which are located and formed such that the magnetoresistive unit is sandwiched between them with a sense current applied in a stacking direction. The magnetoresistive unit comprises a nonmagnetic intermediate layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked and formed such that the nonmagnetic intermediate layer is sandwiched between them. The first shield layer and the second shield layer are each controlled by magnetization direction control means in terms of magnetization direction to create an antiparallel magnetization state where their magnetizations are in opposite directions.
    Type: Application
    Filed: May 28, 2008
    Publication date: December 3, 2009
    Applicant: TDK CORPORATION
    Inventors: Tomohito Mizuno, Koji Shimazawa, Yoshihiro Tsuchiya
  • Publication number: 20090290264
    Abstract: The invention provides a magnetoresistive device of the CPP (current perpendicular to plane) structure, comprising a magnetoresistive unit, and a first, substantially soft magnetic shield layer positioned below and a second, substantially soft magnetic shield layer positioned above, which are located and formed such that the magnetoresistive effect is sandwiched between them from above and below, with a sense current applied in the stacking direction. The magnetoresistive unit comprises a nonmagnetic intermediate layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked and formed such that said nonmagnetic intermediate layer is sandwiched between them. At least one of the first shield layer positioned below and the second shield layer positioned above is configured in a framework form having a planar shape (X-Y plane) defined by the width and length directions of the device.
    Type: Application
    Filed: May 23, 2008
    Publication date: November 26, 2009
    Applicant: TDK CORPORATION
    Inventors: Toshiyuki Ayukawa, Takahiko Machita, Daisuke Miyauchi, Tsutomu Chou, Koji Shimazawa, Shinji Hara, Tomohito Mizuno, Yoshihiro Tsuchiya
  • Publication number: 20090274837
    Abstract: The invention provides a process for the formation of a sensor site of a magnetoresistive device in which the first ferromagnetic layer and a nonmagnetic intermediate layer are formed in order, then surface treatment is applied to the surface of the nonmagnetic intermediate layer, and thereafter the second ferromagnetic layer is formed on the thus treated surface of the nonmagnetic intermediate layer. The surface treatment is implemented by a method of letting a modification element hit right on the surface of the nonmagnetic intermediate layer using a vacuum. The nonmagnetic intermediate layer is composed mainly of an oxide or nitride, and the modification element is a low-melting element having a melting point of 500° C. or lower. It is thus possible to reduce spin scattering while reducing oxidization or nitriding of the surfaces of the ferromagnetic layers used for the sensor site, thereby achieving high MR change rates.
    Type: Application
    Filed: April 30, 2008
    Publication date: November 5, 2009
    Applicant: TDK CORPORATION
    Inventors: Shinji Hara, Yoshihiro Tsuchiya, Tomohito Mizuno
  • Patent number: 7609490
    Abstract: An MR device includes a magnetization pinned film having a nonmagnetic intermediate layer positioned on the opposite side of a magnetization free layer while sandwiching a nonmagnetic spacer layer and made of RuCu. In the case of passing read current in the stacking direction via lower and upper electrodes, decrease in a resistance change amount caused by a second magnetization pinned layer can be suppressed. Further, a first magnetization pinned layer and the second magnetization pined layer which are thicker can be antiferromagnetically coupled to each other in magnetic fields in a wider range. Thus, both increase in the resistance change amount and magnetic field stability can be achieved. Therefore, while maintaining stable operations by reducing the influence of external noise, the invention can address higher recording density by the increase in the resistance change amount as a whole.
    Type: Grant
    Filed: July 21, 2006
    Date of Patent: October 27, 2009
    Assignee: TDK Corporation
    Inventors: Tomohito Mizuno, Daisuke Miyauchi
  • Publication number: 20090237839
    Abstract: A magnetoresistance effect element comprises: a magnetoresistive stack including: first, second and third magnetic layers whose magnetization directions change in accordance with an external magnetic field, said second magnetic layer being located between said first magnetic layer and the third magnetic layer; a first non-magnetic intermediate layer sandwiched between said first and second magnetic layers, said first non-magnetic intermediate layer allowing said first magnetic layer and said second magnetic layer to be exchange-coupled such that the magnetization directions thereof are anti-parallel to each other when no magnetic field is applied; and a second non-magnetic intermediate layer sandwiched between said second and third magnetic layers, said second non-magnetic intermediate layer producing a magnetoresistance effect between said second magnetic layer and said third magnetic layer; wherein sense current is adapted to flow in a direction perpendicular to a film plane; a bias magnetic layer provided
    Type: Application
    Filed: March 20, 2008
    Publication date: September 24, 2009
    Applicant: TDK CORPORATION
    Inventors: Kei Hirata, Satoshi Miura, Tomohito Mizuno, Takeo Kagami
  • Publication number: 20090231762
    Abstract: An MR element includes a pinned layer, a free layer and a nonmagnetic space layer or a tunnel barrier layer sandwiched between the pinned layer and the free layer. A magnetization direction of the free layer is substantially perpendicular to a film surface thereof, and a magnetization direction of the pinned layer is substantially parallel to a film surface thereof.
    Type: Application
    Filed: March 13, 2008
    Publication date: September 17, 2009
    Applicant: TDK CORPORATION
    Inventors: Naoki Ohta, Satoshi Miura, Tomohito Mizuno
  • Patent number: 7580231
    Abstract: A magneto-resistive element has a pinned layer, a free layer, and a spacer layer which is sandwiched between the pinned layer and the free layer. The spacer layer is made of copper. The magneto-resistive element is configured such that sense current is applied in a direction that is perpendicular to layer surfaces. The free layer has: a nonmagnetic layer that includes copper as a main component; and ternary alloy layers each including cobalt (Co), iron (Fe), and nickel (Ni), the ternary alloy layers being disposed on both sides of the nonmagnetic layer. The ternary alloy layer includes nickel and iron at a composition ratio in which a ratio x of an atomic percentage of nickel to a total atomic percentage of nickel and iron is 27%?x?45%.
    Type: Grant
    Filed: October 27, 2006
    Date of Patent: August 25, 2009
    Assignee: TDK Corporation
    Inventors: Daisuke Miyauchi, Tomohito Mizuno
  • Publication number: 20090190270
    Abstract: The invention provides a magnetoresistive device with the CPP (current perpendicular to plane) structure, comprising a nonmagnetic intermediate layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked and formed with said nonmagnetic intermediate layer interposed between them, with a sense current applied in the stacking direction, wherein each of said first and second ferromagnetic layers comprises a sensor area joining to the nonmagnetic intermediate layer near a medium opposite plane and a magnetization direction control area that extends further rearward (toward the depth side) from the position of the rear end of said nonmagnetic intermediate layer; a magnetization direction control multilayer arrangement is interposed at an area where the magnetization direction control area for said first ferromagnetic layer is opposite to the magnetization direction control area for said second ferromagnetic layer in such a way that the magnetizations of the said first and second ferromagnetic l
    Type: Application
    Filed: January 30, 2008
    Publication date: July 30, 2009
    Applicant: TDK Corporation
    Inventors: Tsutomu Chou, Yoshihiro Tsuchiya, Daisuke Miyauchi, Takahiko Machita, Shinji Hara, Tomohito Mizuno, Hironobu Matsuzawa, Toshiyuki Ayukawa, Koji Shimazawa, Kiyoshi Noguchi
  • Patent number: 7564657
    Abstract: Provided are a magnetoresistive device capable of obtaining a larger amount of resistance change and responding to a higher recording density and a thin film magnetic head comprising the magnetoresistive device. A first magnetization fixed film and a second magnetization fixed film have magnetization directions antiparallel to each other, and the second magnetization fixed film farther from a magnetization free layer is made of, for example, a material including at least one selected from the group consisting of tantalum (Ta), chromium (Cr) and vanadium (V), and has a bulk scattering coefficient of 0.25 or less. Thereby, a bulk scattering effect by the second magnetization fixed film which has a function of canceling out the amount of resistance change between the magnetization free layer and the first magnetization fixed film can be prevented, and a magnetoresistive ratio ?R/R can be improved, and recorded magnetic information with a higher recording density can be read out.
    Type: Grant
    Filed: March 11, 2005
    Date of Patent: July 21, 2009
    Assignee: TDk Corporation
    Inventors: Daisuke Miyauchi, Tomohito Mizuno
  • Publication number: 20090174971
    Abstract: A magnetoresistance effect element comprises: a pair of magnetic layers whose magnetization directions form a relative angle therebetween that is variable depending on an external magnetic field; and a crystalline spacer layer sandwiched between the pair of magnetic layers; wherein sense current may flow in a direction that is perpendicular to a film plane of the pair of magnetic layers and the spacer layer. The spacer layer includes a crystalline oxide, and either or both magnetic layers whose magnetization direction is variable depending on the external magnetic field has a layer configuration in which a CoFeB layer is sandwiched between a CoFe layer and a NiFe layer and is positioned between the spacer layer and the NiFe layer.
    Type: Application
    Filed: January 3, 2008
    Publication date: July 9, 2009
    Inventors: Yoshihiro Tsuchiya, Shinji Hara, Tomohito Mizuno, Satoshi Miura, Takumi Yanagisawa
  • Publication number: 20090168264
    Abstract: In an MR element, first and second ferromagnetic layers are antiferromagnetically coupled to each other through a spacer layer, and have magnetizations that are in opposite directions when no external magnetic field is applied thereto and that change directions in response to an external magnetic field. The spacer layer and the second ferromagnetic layer are stacked in this order on the first ferromagnetic layer. The first ferromagnetic layer includes a plurality of ferromagnetic material layers stacked, and an insertion layer made of a nonmagnetic material and inserted between respective two of the ferromagnetic material layers that are adjacent to each other along the direction in which the layers are stacked. The ferromagnetic material layers and the spacer layer each include a component whose crystal structure is a face-centered cubic structure.
    Type: Application
    Filed: December 27, 2007
    Publication date: July 2, 2009
    Applicant: TDK CORPORATION
    Inventors: Shinji Hara, Koji Shimazawa, Yoshihiro Tsuchiya, Tomohito Mizuno, Tsuyoshi Ichiki, Toshiyuki Ayukawa
  • Publication number: 20090128965
    Abstract: A magnetic field detecting element has a stack which includes a NiCr layer, a first magnetic layer whose magnetization direction varies in accordance with an external magnetic field, a non-magnetic spacer layer, and a second magnetic layer whose magnetization direction varies in accordance with the external magnetic field, said NiCr layer, said first magnetic layer, said spacer layer and said second magnetic layer being disposed in this order and being arranged in contact with each other, wherein a sense current is adapted to flow in a direction that is perpendicular to a film surface of said stack; and a bias magnetic layer which is disposed on a side of said stack, said side being opposite to an air bearing surface of said stack, wherein said bias magnetic layer is adapted to apply a bias magnetic field to said stack in a direction that is perpendicular to said air bearing surface.
    Type: Application
    Filed: November 15, 2007
    Publication date: May 21, 2009
    Inventors: Tomohito MIZUNO, Yoshihiro TSUCHIYA, Shinji HARA, Koji SHIMAZAWA, Daisuke MIYAUCHI, Takahiko MACHITA, Tsutomu CHOU, Toshiyuki AYUKAWA, Hironobu MATSUZAWA, Tsuyoshi ICHIKI
  • Patent number: 7535682
    Abstract: A magneto-resistance element according to the present invention has a pinned layer whose magnetization direction is fixed; a free layer whose magnetization direction varies in accordance with an external magnetic field; and a nonmagnetic spacer layer that is arranged between the pinned layer and the free layer, at least the pinned layer or the free layer includes a layer having Heusler alloy represented by composition formula X2YZ (where X is a precious metal element, Y is a transition metal of Mn, V, or Ti group, Z is an element from group III to group V), and a part of composition X is replaced with Co, and an atomic composition ratio of Co in composition X is from 0.5 to 0.85.
    Type: Grant
    Filed: September 13, 2006
    Date of Patent: May 19, 2009
    Assignee: TDK Corporation
    Inventors: Koji Shimazawa, Yoshihiro Tsuchiya, Tomohito Mizuno
  • Patent number: 7533456
    Abstract: A free layer functions such that a magnetization direction changes depending on an external magnetic field, and is made up of a multilayer structure including a first Heusler alloy layer, and a fixed magnetization layer takes a form wherein an inner pin layer and an outer pin layer are stacked one upon another with a nonmagnetic intermediated layer sandwiched between them. The inner pin layer is made up of a multilayer structure including a second Heusler alloy layer. The first and second Heusler alloy layers are each formed by a co-sputtering technique using a split target split into at least two sub-targets in such a way as to constitute a Heusler alloy layer composition. When the Heusler alloy layer is formed, therefore, it is possible to bring up a film-deposition rate, improve productivity, and improve the performance of the device.
    Type: Grant
    Filed: June 1, 2007
    Date of Patent: May 19, 2009
    Assignee: TDK Corporation
    Inventors: Yoshihiro Tsuchiya, Tomohito Mizuno, Koji Shimazawa
  • Publication number: 20090086383
    Abstract: The invention provides a giant magneto-resistive effect device of the CPP (current perpendicular to plane) structure (CPP-GMR device) comprising a spacer layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked together with said spacer layer sandwiched between them, with a sense current passed in the stacking direction, wherein the first ferromagnetic layer and the second ferromagnetic layer function such that the angle made between the directions of magnetizations of both layers change relatively depending on an external magnetic field, said spacer layer contains a semiconductor oxide layer, and a nitrogen element-interface protective layer is provided at a position where the semiconductor oxide layer forming the whole or a part of said spacer layer contacts an insulating layer.
    Type: Application
    Filed: October 1, 2007
    Publication date: April 2, 2009
    Applicant: TDK CORPORATION
    Inventors: Shinji Hara, Daisuke Miyauchi, Koji Shimazawa, Yoshihiro Tsuchiya, Tomohito Mizuno, Takahiko Machita
  • Patent number: 7510787
    Abstract: An MR element has a pinned layer, a spacer layer, and a free layer successively stacked in the order named. The free layer includes a Heusler alloy layer in at least a region thereof adjacent to the spacer layer. An oxide is distributed as sea-islands in the interface between the Heusler alloy layer and the spacer layer. The Heusler alloy layer virtually has a stoichiometric composition. The oxide has an RA in the range from 0.10 ??m2 to 0.36 ??m2.
    Type: Grant
    Filed: February 5, 2007
    Date of Patent: March 31, 2009
    Assignee: TDK Corporation
    Inventors: Yoshihiro Tsuchiya, Tomohito Mizuno, Daisuke Miyauchi, Koji Shimazawa
  • Publication number: 20090067099
    Abstract: An MR element includes an MR stack including a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer disposed between the first and the second ferromagnetic layer. The MR stack has an outer surface, and the spacer layer has a periphery located in the outer surface of the MR stack. The magnetoresistive element further includes a layered film that touches the periphery of the spacer layer. The spacer layer includes a semiconductor layer formed using an oxide semiconductor as a material. The layered film includes a first layer, a second layer, and a third layer stacked in this order. The first layer is formed of the same material as the semiconductor layer, and touches the periphery of the spacer layer. The second layer is a metal layer that forms a Schottky barrier at the interface between the first layer and the second layer. The third layer is an insulating layer.
    Type: Application
    Filed: September 11, 2007
    Publication date: March 12, 2009
    Applicant: TDK CORPORATION
    Inventors: Yoshihiro Tsuchiya, Koji Shimazawa, Tomohito Mizuno, Shinji Hara, Daisuke Miyauchi, Takahiko Machita
  • Publication number: 20090061258
    Abstract: A magnetic field detecting element comprises: a stack which includes first, second and third magnetic layers whose magnetization directions change in accordance with an external magnetic field, a first non-magnetic intermediate layer which is sandwiched between the first magnetic layer and the second magnetic layer, the first non-magnetic intermediate layer producing a magnetoresistance effect between the first magnetic layer and the second magnetic layer, and a second non-magnetic intermediate layer which is sandwiched between the second magnetic layer and the third magnetic layer, the second non-magnetic intermediate layer allowing the second magnetic layer and the third magnetic layer to be exchange-coupled such that magnetization directions thereof are anti-parallel to each other under no magnetic field, the stack being adapted such that sense current flows in a direction that is perpendicular to a film surface thereof; and a bias magnetic layer which is provided on a side of the stack, the side being opp
    Type: Application
    Filed: August 30, 2007
    Publication date: March 5, 2009
    Inventors: Tomohito MIZUNO, Yoshihiro TSUCHIYA, Shinji HARA, Koji SHIMAZAWA, Tsutomu CHOU