Patents by Inventor Hironobu Matsuzawa

Hironobu Matsuzawa 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: 9824701
    Abstract: A microwave assisted magnetic head includes a main magnetic pole; a trailing shield; and a spin torque oscillator provided between the main magnetic pole and the trailing shield. The spin torque oscillator has a first end surface configuring a part of an air bearing surface, a second end surface facing the main magnetic pole, and a third end surface facing the first end surface, the first angle ?1 made by the first end surface and the second end surface is smaller than the second angle ?2 formed by the second end surface and the third end surface, and the second angle ?2 is 80 to 100 degrees.
    Type: Grant
    Filed: April 26, 2016
    Date of Patent: November 21, 2017
    Assignee: TDK Corporation
    Inventors: Zhenyao Tang, Tetsuya Roppongi, Yoshikazu Soeno, Hironobu Matsuzawa, Hirokazu Takahashi
  • Publication number: 20170309299
    Abstract: A microwave assisted magnetic head includes a main magnetic pole; a trailing shield; and a spin torque oscillator provided between the main magnetic pole and the trailing shield. The spin torque oscillator has a first end surface configuring a part of an air bearing surface, a second end surface facing the main magnetic pole, and a third end surface facing the first end surface, the first angle ?1 made by the first end surface and the second end surface is smaller than the second angle ?2 formed by the second end surface and the third end surface, and the second angle ?2 is 80 to 100 degrees.
    Type: Application
    Filed: April 26, 2016
    Publication date: October 26, 2017
    Inventors: Zhenyao TANG, Tetsuya ROPPONGI, Yoshikazu SOENO, Hironobu MATSUZAWA, Hirokazu TAKAHASHI
  • 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: 8593766
    Abstract: A magneto-resistive effect (MR) element includes first and second magnetic layers in which a relative angle formed by magnetization directions changes responsive to an external magnetic field, and a spacer layer positioned between the first and second magnetic layers. The first magnetic layer is positioned closer to a substrate above which the MR element is formed than the second magnetic layer. The spacer layer includes copper and metal intermediate layers and a main spacer layer composed primarily of gallium oxide. The copper and metal intermediate layers are positioned between the main spacer and first magnetic layers. The metal intermediate layer is positioned between the copper and main spacer layers. The metal intermediate layer is composed primarily of at least one from a group of one of magnesium and at least partially oxidized magnesium, and one of aluminum and at least partially oxidized aluminum.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: November 26, 2013
    Assignee: TDK Corporation
    Inventors: Yoshihiro Tsuchiya, Tsutomu Chou, Hironobu Matsuzawa, Hayato Koike
  • Patent number: 8564911
    Abstract: A magneto-resistive effect (MR) element includes: first and second magnetic layers in which a relative angle formed by magnetization directions changes according to an external magnetic field; and a spacer layer positioned between the first magnetic layer and the second magnetic layer. The spacer layer includes a main spacer layer composed of gallium oxide as a primary component and containing at least one metal element selected from a group of magnesium, zinc, indium and aluminum.
    Type: Grant
    Filed: February 17, 2011
    Date of Patent: October 22, 2013
    Assignee: TDK Corporation
    Inventors: Hayato Koike, Tsutomu Chou, Yoshihiro Tsuchiya, Hironobu Matsuzawa
  • Patent number: 8498083
    Abstract: A magneto-resistive effect (MR) element includes first and second magnetic layers where a relative angle formed by magnetization directions changes in response to an external magnetic field and a spacer layer positioned between the first magnetic layer and the second magnetic layer. The first magnetic layer is positioned closer to a substrate above which the MR element is formed than the second magnetic layer. The spacer layer includes a main spacer layer that is composed of gallium oxide as a primary component and a bottom layer that is positioned between the main spacer layer and the first magnetic layer and that is composed of partially oxidized copper as a primary component.
    Type: Grant
    Filed: March 16, 2011
    Date of Patent: July 30, 2013
    Assignee: TDK Corporation
    Inventors: Hayato Koike, Tsutomu Chou, Yoshihiro Tsuchiya, Hironobu Matsuzawa
  • Patent number: 8441763
    Abstract: A magneto-resistive effect (MR) element includes first and second magnetic layers in which a relative angle formed by magnetization directions changes in response to an external magnetic field, and a spacer layer positioned between the first magnetic layer and the second magnetic layer. The spacer layer, on an air bearing surface, has a larger film thickness at both side edge parts in a track width direction than a film thickness at a central part in a track width direction. When a region of the spacer layer on the air bearing surface is divided into quarters which are both side edge part regions and two central regions such that track width direction lengths are equivalent, an average film thickness of a region where the both side edge regions are combined is preferably larger than a region where the two central regions are combined.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: May 14, 2013
    Assignee: TDK Corporation
    Inventors: Tsutomu Chou, Yoshihiro Tsuchiya, Hironobu Matsuzawa, Hayato Koike
  • Patent number: 8432645
    Abstract: An MR element includes a stack, being a pillar or trapezoidal stack, including first and second magnetic layers in which a relative angle formed by magnetization directions changes according to an external magnetic field, and a spacer layer that is positioned between the first magnetic layer and the second magnetic layer, and that is provided with a main spacer layer that is composed of gallium oxide, zinc oxide or magnesium oxide as a primary component, wherein, one part of side surfaces of the stack forms a part of an air bearing surface; and a cover layer that covers at least another part of the side surfaces of the stack and that is composed of gallium oxide as a primary component.
    Type: Grant
    Filed: January 31, 2011
    Date of Patent: April 30, 2013
    Assignee: TDK Corporation
    Inventors: Hironobu Matsuzawa, Yoshihiro Tsuchiya, Hayato Koike, Tsutomu Chou
  • Patent number: 8405935
    Abstract: A magnetoresistive effect element (MR element) includes first and second magnetic layers of which relative angles formed by magnetization directions change in relation to an external magnetic field; and a spacer layer positioned between the first magnetic layer and the second magnetic layer. The first magnetic layer is positioned on a side closer than the second magnetic layer in regards to a substrate above which the magnetoresistive effect element is formed, and the spacer layer includes a main spacer layer made of gallium oxide as the primary component, and a first nonmagnetic layer positioned between the main spacer layer and the first magnetic layer and contains copper and gallium.
    Type: Grant
    Filed: December 28, 2010
    Date of Patent: March 26, 2013
    Assignee: TDK Corporation
    Inventors: Tsutomu Chou, Yoshihiro Tsuchiya, Hironobu Matsuzawa, Hayato Koike
  • Patent number: 8379350
    Abstract: An MR element includes a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer disposed between the first and second ferromagnetic layers. The spacer layer includes a nonmagnetic metal layer, a first oxide semiconductor layer, and a second oxide semiconductor layer that are stacked in this order. The nonmagnetic metal layer is made of Cu, and has a thickness in the range of 0.3 to 1.5 nm. The first oxide semiconductor layer is made of a Ga oxide semiconductor, and has a thickness in the range of 0.5 to 2.0 nm. The second oxide semiconductor layer is made of a Zn oxide semiconductor, and has a thickness in the range of 0.1 to 1.0 nm.
    Type: Grant
    Filed: June 30, 2010
    Date of Patent: February 19, 2013
    Assignee: TDK Corporation
    Inventors: Hironobu Matsuzawa, Yoshihiro Tsuchiya
  • Patent number: 8345390
    Abstract: An MR element according to the present invention has the superior effects that further improve an MR ratio because a structure of a spacer layer 40 is configured of a certain three-layer structure with certain materials, and at least one of a first ferromagnetic layer 30 and a second ferromagnetic layer 50 contains a certain amount of an element selected from the group of nitrogen (N), carbon (C), and oxygen (O).
    Type: Grant
    Filed: February 26, 2009
    Date of Patent: January 1, 2013
    Assignee: TDK Corporation
    Inventors: Yoshihiro Tsuchiya, Shinji Hara, Tsutomu Chou, Hironobu Matsuzawa
  • Patent number: 8331063
    Abstract: An MR element in a CPP-GMR structure includes a first ferromagnetic layer, a spacer layer that is epitaxially formed on the first ferromagnetic layer, a second ferromagnetic layer that is located on the spacer layer, and that is laminated with the first ferromagnetic layer to sandwich the spacer layer. A sense current flows along a lamination direction of the first and second ferromagnetic layers. Angle of magnetization directions of the first ferromagnetic layer and the second ferromagnetic layer relatively change due to an externally applied magnetic field.
    Type: Grant
    Filed: July 10, 2009
    Date of Patent: December 11, 2012
    Assignee: TDK Corporation
    Inventors: Shinji Hara, Tsutomu Chou, Yoshihiro Tsuchiya, Hironobu Matsuzawa
  • Patent number: 8274764
    Abstract: A magneto-resistive effect (MR) element includes a first magnetic layer and a second magnetic layer in which a relative angle of magnetization directions of the first and second magnetic layers changes according to an external magnetic field; and a spacer layer that is provided between the first magnetic layer and the second magnetic layer. The spacer layer contains gallium nitride (GaN) as a main component.
    Type: Grant
    Filed: March 10, 2009
    Date of Patent: September 25, 2012
    Assignee: TDK Corporation
    Inventors: Shinji Hara, Yoshihiro Tsuchiya, Tsutomu Chou, Hironobu Matsuzawa
  • Publication number: 20120237796
    Abstract: A magneto-resistive effect (MR) element includes first and second magnetic layers where a relative angle formed by magnetization directions changes in response to an external magnetic field and a spacer layer positioned between the first magnetic layer and the second magnetic layer. The first magnetic layer is positioned closer to a substrate above which the MR element is formed than the second magnetic layer. The spacer layer includes a main spacer layer that is composed of gallium oxide as a primary component and a bottom layer that is positioned between the main spacer layer and the first magnetic layer and that is composed of partially oxidized copper as a primary component.
    Type: Application
    Filed: March 16, 2011
    Publication date: September 20, 2012
    Applicant: TDK Corporation
    Inventors: Hayato KOIKE, Tsutomu CHOU, Yoshihiro TSUCHIYA, Hironobu MATSUZAWA
  • Publication number: 20120212860
    Abstract: A magneto-resistive effect (MR) element includes: first and second magnetic layers in which a relative angle formed by magnetization directions changes according to an external magnetic field; and a spacer layer positioned between the first magnetic layer and the second magnetic layer. The spacer layer includes a main spacer layer composed of gallium oxide as a primary component and containing at least one metal element selected from a group of magnesium, zinc, indium and aluminum.
    Type: Application
    Filed: February 17, 2011
    Publication date: August 23, 2012
    Applicant: TDK Corporation
    Inventors: Hayato KOIKE, Tsutomu CHOU, Yoshihiro TSUCHIYA, Hironobu MATSUZAWA
  • Publication number: 20120214020
    Abstract: A magneto-resistive effect (MR) element includes first and second magnetic layers in which a relative angle formed by magnetization directions changes in response to an external magnetic field, and a spacer layer positioned between the first magnetic layer and the second magnetic layer. The spacer layer, on an air bearing surface, has a larger film thickness at both side edge parts in a track width direction than a film thickness at a central part in a track width direction. When a region of the spacer layer on the air bearing surface is divided into quarters which are both side edge part regions and two central regions such that track width direction lengths are equivalent, an average film thickness of a region where the both side edge regions are combined is preferably larger than a region where the two central regions are combined.
    Type: Application
    Filed: February 22, 2011
    Publication date: August 23, 2012
    Applicant: TDK Corporation
    Inventors: Tsutomu CHOU, Yoshihiro Tsuchiya, Hironobu Matsuzawa, Hayato Koike
  • Publication number: 20120212859
    Abstract: A magneto-resistive effect (MR) element includes first and second magnetic layers in which a relative angle formed by magnetization directions changes in response to an external magnetic field, and a spacer layer positioned between the first magnetic layer and the second magnetic layer. The first magnetic layer is positioned closer to a substrate above which the MR element is formed than the second magnetic layer. The spacer layer includes a copper layer, a metal intermediate layer and a main spacer layer composed of gallium oxide as a primary component. The copper layer and the metal intermediate layer are positioned between the main spacer layer and the first magnetic layer. The metal intermediate layer is positioned between the copper layer and the main spacer layer.
    Type: Application
    Filed: February 22, 2011
    Publication date: August 23, 2012
    Applicant: TDK Corporation
    Inventors: Yoshihiro TSUCHIYA, Tsutomu Chou, Hironobu Matsuzawa, Hayato Koike
  • Publication number: 20120196153
    Abstract: An MR element includes a stack, being a pillar or trapezoidal stack, including first and second magnetic layers in which a relative angle formed by magnetization directions changes according to an external magnetic field, and a spacer layer that is positioned between the first magnetic layer and the second magnetic layer, and that is provided with a main spacer layer that is composed of gallium oxide, zinc oxide or magnesium oxide as a primary component, wherein, one part of side surfaces of the stack forms a part of an air bearing surface; and a cover layer that covers at least another part of the side surfaces of the stack and that is composed of gallium oxide as a primary component.
    Type: Application
    Filed: January 31, 2011
    Publication date: August 2, 2012
    Applicant: TDK Corporation
    Inventors: Hironobu MATSUZAWA, Yoshihiro Tsuchiya, Hayato Koike, Tsutomu Chou
  • Publication number: 20120164484
    Abstract: A magnetoresistive effect element (MR element) includes first and second magnetic layers of which relative angles formed by magnetization directions change in relation to an external magnetic field; and a spacer layer positioned between the first magnetic layer and the second magnetic layer. The first magnetic layer is positioned on a side closer than the second magnetic layer in regards to a substrate above which the magnetoresistive effect element is formed, and the spacer layer includes a main spacer layer made of gallium oxide as the primary component, and a first nonmagnetic layer positioned between the main spacer layer and the first magnetic layer and contains copper and gallium.
    Type: Application
    Filed: December 28, 2010
    Publication date: June 28, 2012
    Applicant: TDK Corporation
    Inventors: Tsutomu CHOU, Yoshihiro Tsuchiya, Hironobu Matsuzawa, Hayato Koike
  • Patent number: 8194364
    Abstract: In an MR element of the present invention, an effect of an extremely-high MR ratio is obtained since a crystal structure of a CoFe magnetic layer in the vicinity of an interface with a spacer layer is formed as a close packed structure, such as an hcp structure and an fcc structure, and a total existing ratio of these crystal structures is 25% or more by an area ratio.
    Type: Grant
    Filed: August 31, 2009
    Date of Patent: June 5, 2012
    Assignee: TDK Corporation
    Inventors: Shinji Hara, Tsutomu Chou, Yoshihiro Tsuchiya, Hironobu Matsuzawa