Patents by Inventor Naomichi Degawa

Naomichi Degawa 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: 8891208
    Abstract: An MR element suppressing a false writing into a medium with an MR part has a CPP structure. The MR part includes a nonmagnetic intermediate layer and first and second ferromagnetic layers so as to interpose the nonmagnetic intermediate layer. First and second shield layers respectively have an inclining magnetization structure of which a magnetization is inclined with regard to a track width direction. The first and second ferromagnetic layers are respectively, magnetically coupled with the first and second shield layers. A magnetization direction adjustment layer for adjusting at least a magnetization direction of the first ferromagnetic layer is positioned at a rear end surface side of the first ferromagnetic layer, which is opposite to a front end surface receiving a magnetic field detected in the MR part.
    Type: Grant
    Filed: March 29, 2013
    Date of Patent: November 18, 2014
    Assignee: TDK Corporation
    Inventors: Naomichi Degawa, Takahiko Machita, Takekazu Yamane, Takumi Yanagisawa, Satoshi Miura, Kenta Hamamoto, Minoru Ota, Kenzo Makino, Shohei Kawasaki
  • Publication number: 20140293474
    Abstract: An MR element includes an MR part and upper and lower shield layers in a CPP structure. The MR element has side shield layers so as to interpose the MR part between the side shield layers in a track width direction. The MR part comprises a nonmagnetic intermediate layer and first and second ferromagnetic layers so as to interpose the nonmagnetic intermediate layer between the ferromagnetic layers. Each of the upper and lower shield layers has an inclined magnetization structure such that its magnetization is inclined relative to the track width direction. The side shield layers are magnetically coupled with the upper shield layer, respectively. The second ferromagnetic layer is indirectly magnetically coupled with the lower shield layer via an exchange-coupling functional gap layer. The side shield layer applies a bias magnetic field to the first ferromagnetic layer; and magnetizations of the first and second ferromagnetic layers are substantially orthogonal.
    Type: Application
    Filed: March 29, 2013
    Publication date: October 2, 2014
    Applicant: TDK CORPORATION
    Inventors: Takekazu YAMANE, Takahiko MACHITA, Naomichi DEGAWA, Minoru OTA, Kenta HAMAMOTO
  • Publication number: 20140293475
    Abstract: An MR element suppressing a false writing into a medium with an MR part has a CPP structure. The MR part includes a nonmagnetic intermediate layer and first and second ferromagnetic layers so as to interpose the nonmagnetic intermediate layer. First and second shield layers respectively have an inclining magnetization structure of which a magnetization is inclined with regard to a track width direction. The first and second ferromagnetic layers are respectively, magnetically coupled with the first and second shield layers. A magnetization direction adjustment layer for adjusting at least a magnetization direction of the first ferromagnetic layer is positioned at a rear end surface side of the first ferromagnetic layer, which is opposite to a front end surface receiving a magnetic field detected in the MR part.
    Type: Application
    Filed: March 29, 2013
    Publication date: October 2, 2014
    Inventors: Naomichi DEGAWA, Takahiko MACHITA, Takekazu YAMANE, Takumi YANAGISAWA, Satoshi MIURA, Kenta HAMAMOTO, Minoru OTA, Kenzo MAKINO, Shohei KAWASAKI
  • Publication number: 20140268405
    Abstract: A magnetoresistive effect element that prevents a recording medium from deteriorating by effectively inhibiting erroneous writing to a medium or the like includes a magnetoresistive effect part, and an upper shield layer and a lower shield layer that are laminated and formed in a manner sandwiching the magnetoresistive effect part from above and below, and is in a current perpendicular to plane (CPP) structure in which a sense current is applied in a lamination direction.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Inventors: Takahiko MACHITA, Naomichi DEGAWA, Takekazu YAMANE, Takumi YANAGISAWA, Satoshi MIURA, Kenta HAMAMOTO, Minoru OTA, Kenzo MAKINO, Shohei KAWASAKI
  • Patent number: 8547091
    Abstract: A measuring method measuring a resistance of a resistor of a magnetic sensor that includes the resistor is provided. The method includes a step of measuring an output voltage of the magnetic sensor in an AC magnetic field, a step of measuring a first combined resistance of the MR element and the resistor in no magnetic field, a step of measuring a second combined resistance of the MR element and the resistor in a constant magnetic field of which a direction and strength are substantially the same as a magnetic field, a step of measuring a third combined resistance of the MR element and the resistor in another constant magnetic field of which a direction and strength are substantially the same as another magnetic field, and a step of calculating the resistance of the resistor based on the output voltage, the first, second and third combined resistance.
    Type: Grant
    Filed: December 14, 2010
    Date of Patent: October 1, 2013
    Assignee: TDK Corporation
    Inventors: Takekazu Yamane, Naomichi Degawa
  • Patent number: 8462467
    Abstract: A thin film magnetic head includes: a magneto resistance effect film of which electrical resistance varies corresponding to an external magnetic field; a pair of shields provided on both sides in a manner of sandwiching the MR film in a direction that is orthogonal to a film surface of the MR film; an anisotropy providing layer that provides exchange anisotropy to a first shield of the pair of shields in order to magnetize the first shield in a desired direction, and that is disposed on the opposite side from the MR film with respect to the first shield; and side shields that are disposed on both sides of the MR film in a track width direction and that include soft magnetic layers magnetically connected with the first shield.
    Type: Grant
    Filed: October 8, 2010
    Date of Patent: June 11, 2013
    Assignee: TDK Corporation
    Inventors: Takumi Yanagisawa, Yasushi Nishioka, Takahiko Machita, Satoshi Miura, Takayasu Kanaya, Kenzo Makino, Yoshikazu Sawada, Takekazu Yamane, Naomichi Degawa, Kosuke Tanaka, Soji Koide, Daisuke Miyauchi
  • Patent number: 8456962
    Abstract: A magnetic head that writes information to a recording medium includes a magnetic pole layer that generates a writing magnetic field to the recording medium, a microstripline that is disposed in proximity to the magnetic pole layer and to which high frequency current is applied, and a ferromagnetic thin film that is disposed on a portion of the microstripline that faces the recording medium, and that generates a high frequency alternate-current (AC) magnetic field to be applied to the recording medium, using a current magnetic field generated on the microstripline due to the high frequency current.
    Type: Grant
    Filed: March 31, 2011
    Date of Patent: June 4, 2013
    Assignee: TDK Corporation
    Inventors: Takekazu Yamane, Yoshikazu Soeno, Akimasa Kaizu, Naomichi Degawa, Hayato Koike
  • Patent number: 8437106
    Abstract: A thin film magnetic head includes; an MR film that includes a pinned layer of which a magnetization direction is pinned, a free layer of which a magnetization direction varies, and a spacer that is disposed therebetween; a pair of shields that are disposed on both sides sandwiching the MR film in a direction orthogonal to a film surface of the MR film; and an anisotropy providing layer that provides anisotropy to a first shield so that the first shield is magnetized in a desired direction, and that is disposed on an opposite side from the MR film with respect to the first shield. The MR film includes a magnetic coupling layer that is disposed between the first shield and the free layer and that magnetically couples the first shield with the free layer.
    Type: Grant
    Filed: October 8, 2010
    Date of Patent: May 7, 2013
    Assignee: TDK Corporation
    Inventors: Takumi Yanagisawa, Yasushi Nishioka, Takahiko Machita, Satoshi Miura, Takayasu Kanaya, Kenzo Makino, Yoshikazu Sawada, Takekazu Yamane, Naomichi Degawa, Kosuke Tanaka, Soji Koide, Daisuke Miyauchi
  • Patent number: 8402635
    Abstract: A method of manufacturing a magnetic head, including a magneto resistance effect (MR) element that reads a magnetic recording medium, is disclosed. A multilayer film is formed on a shield layer. Unnecessary portions of the multilayer film are removed from both sides of the MR element in a first direction orthogonal to a lamination direction of the multilayer film and parallel to the MR element surface facing the magnetic recording medium. An insulating layer is formed on a surface exposed by removal of the unnecessary portions. An integrated soft magnetic layer covering both sides of the MR element in the first direction and an upper side of the MR element is formed, thereby configuring a second shield layer. An anisotropy application layer is formed on the second shield layer, thereby providing exchange anisotropy to the soft magnetic layer, and magnetizing the soft magnetic layer in a predetermined direction.
    Type: Grant
    Filed: March 21, 2011
    Date of Patent: March 26, 2013
    Assignee: TDK Corporation
    Inventors: Naomichi Degawa, Takumi Yanagisawa, Satoshi Miura, Yoshikazu Sawada, Takahiko Machita, Kenzo Makino, Takekazu Yamane, Shohei Kawasaki
  • Publication number: 20120250472
    Abstract: A magnetic head that writes information to a recording medium includes a magnetic pole layer that generates a writing magnetic field to the recording medium, a microstripline that is disposed in proximity to the magnetic pole layer and to which high frequency current is applied, and a ferromagnetic thin film that is disposed on a portion of the microstripline that faces the recording medium, and that generates a high frequency alternate-current (AC) magnetic field to be applied to the recording medium, using a current magnetic field generated on the microstripline due to the high frequency current.
    Type: Application
    Filed: March 31, 2011
    Publication date: October 4, 2012
    Applicant: TDK Corporation
    Inventors: Takekazu YAMANE, Yoshikazu Soeno, Akimasa Kaizu, Naomichi Degawa, Hayato Koike
  • Publication number: 20120250189
    Abstract: A magnetic head that reads information of a magnetic recording medium is provided. The magnetic head according to one embodiment includes: an MR element, formed with multilayer films, of which an electrical resistance changes according to an external magnetic field; a first shield layer that is disposed on a lower side in an lamination direction of the MR element; a second shield layer that is disposed on an upper side in the lamination direction of the MR element, and that applies voltage to the MR element together with the first shield layer; and side shield layers that are disposed on both sides of the MR element in a truck width direction. The side shield layers include soft magnetic layers and hard magnetic layers magnetized in a predetermined direction.
    Type: Application
    Filed: March 29, 2011
    Publication date: October 4, 2012
    Applicant: TDK Corporation
    Inventors: Naomichi DEGAWA, Takumi Yanagisawa, Satoshi Miura, Yoshikazu Sawada, Takahiko Machita, Kenzo Makino, Takekazu Yamane, Shohei Kawasaki
  • Publication number: 20120240390
    Abstract: A method of manufacturing a magnetic head that includes a magneto resistance effect (MR) element of which an electrical resistance changes according to an external magnetic field and shield layers surrounding the MR element, and that reads information of a magnetic recording medium is provided.
    Type: Application
    Filed: March 21, 2011
    Publication date: September 27, 2012
    Applicant: TDK Corporation
    Inventors: Naomichi Degawa, Takumi Yanagisawa, Satoshi Miura, Yoshikazu Sawada, Takahiko Machita, Kenzo Makino, Takekazu Yamane, Shohei Kawasaki
  • Publication number: 20120146633
    Abstract: A measuring method measuring a resistance of a resistor of a magnetic sensor that includes the resistor is provided. The method includes a step of measuring an output voltage of the magnetic sensor in an AC magnetic field, a step of measuring a first combined resistance of the MR element and the resistor in no magnetic field, a step of measuring a second combined resistance of the MR element and the resistor in a constant magnetic field of which a direction and strength are substantially the same as a magnetic field, a step of measuring a third combined resistance of the MR element and the resistor in another constant magnetic field of which a direction and strength are substantially the same as another magnetic field, and a step of calculating the resistance of the resistor based on the output voltage, the first, second and third combined resistance.
    Type: Application
    Filed: December 14, 2010
    Publication date: June 14, 2012
    Applicant: TDK Corporation
    Inventors: Takekazu YAMANE, Naomichi Degawa
  • Publication number: 20120087046
    Abstract: A thin film magnetic head includes: a magneto resistance effect film of which electrical resistance varies corresponding to an external magnetic field; a pair of shields provided on both sides in a manner of sandwiching the MR film in a direction that is orthogonal to a film surface of the MR film; an anisotropy providing layer that provides exchange anisotropy to a first shield of the pair of shields in order to magnetize the first shield in a desired direction, and that is disposed on the opposite side from the MR film with respect to the first shield; and side shields that are disposed on both sides of the MR film in a track width direction and that include soft magnetic layers magnetically connected with the first shield.
    Type: Application
    Filed: October 8, 2010
    Publication date: April 12, 2012
    Applicant: TDK Corporation
    Inventors: Takumi Yanagisawa, Yasushi Nishioka, Takahiko Machita, Satoshi Miura, Takayasu Kanaya, Kenzo Makino, Yoshikazu Sawada, Takekazu Yamane, Naomichi Degawa, Kosuke Tanaka, Soji Koide, Daisuke Miyauchi
  • Publication number: 20120087045
    Abstract: A thin film magnetic head includes; an MR film that includes a pinned layer of which a magnetization direction is pinned, a free layer of which a magnetization direction varies, and a spacer that is disposed therebetween; a pair of shields that are disposed on both sides sandwiching the MR film in a direction orthogonal to a film surface of the MR film; and an anisotropy providing layer that provides anisotropy to a first shield so that the first shield is magnetized in a desired direction, and that is disposed on an opposite side from the MR film with respect to the first shield. The MR film includes a magnetic coupling layer that is disposed between the first shield and the free layer and that magnetically couples the first shield with the free layer.
    Type: Application
    Filed: October 8, 2010
    Publication date: April 12, 2012
    Applicant: TDK Corporation
    Inventors: Takumi Yanagisawa, Yasushi Nishioka, Takahiko Machita, Satoshi Miura, Takayasu Kanaya, Kenzo Makino, Yoshikazu Sawada, Takekazu Yamane, Naomichi Degawa, Kosuke Tanaka, Soji Koide, Daisuke Miyauchi