Patents by Inventor Takahiko Machita

Takahiko Machita 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: 20170270954
    Abstract: A magnetic head includes a magneto-resistance effect element in the form of a multilayer film, a pair of shields between which the magneto-resistance effect element is interposed in the lamination direction of the layers of the magneto-resistance effect element and each functioning as an electrode, a pair of side shields with one of said side shields on each side of the magneto-resistance effect element in the direction perpendicular to the lamination direction of the magneto-resistance effect element interposed between the pair of shields, the side shields magnetically coupled to either of the pair of shields, and an anisotropy-application layer disposed adjacent to the shield magnetically coupled to the pair of side shields. The pair of shields, the magneto-resistance effect element, and the pair of side shields are exposed on the air bearing surface facing a recording medium.
    Type: Application
    Filed: March 18, 2016
    Publication date: September 21, 2017
    Inventors: Tetsuya HIRAKI, Minoru OTA, Hisayoshi WATANABE, Takahiko MACHITA, Hideyuki UKITA
  • Patent number: 9767834
    Abstract: A magnetic head includes a magneto-resistance effect element in the form of a multilayer film, a pair of shields between which the magneto-resistance effect element is interposed in the lamination direction of the layers of the magneto-resistance effect element and each functioning as an electrode, a pair of side shields with one of said side shields on each side of the magneto-resistance effect element in the direction perpendicular to the lamination direction of the magneto-resistance effect element interposed between the pair of shields, the side shields magnetically coupled to either of the pair of shields, and an anisotropy-application layer disposed adjacent to the shield magnetically coupled to the pair of side shields. The pair of shields, the magneto-resistance effect element, and the pair of side shields are exposed on the air bearing surface facing a recording medium.
    Type: Grant
    Filed: March 18, 2016
    Date of Patent: September 19, 2017
    Assignee: TDK Corporation
    Inventors: Tetsuya Hiraki, Minoru Ota, Hisayoshi Watanabe, Takahiko Machita, Hideyuki Ukita
  • Patent number: 9129622
    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: Grant
    Filed: March 15, 2013
    Date of Patent: September 8, 2015
    Assignee: TDK Corporation
    Inventors: Takahiko Machita, Naomichi Degawa, Takekazu Yamane, Takumi Yanagisawa, Satoshi Miura, Kenta Hamamoto, Minoru Ota, Kenzo Makino, Shohei Kawasaki
  • Patent number: 8913349
    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: Grant
    Filed: March 29, 2013
    Date of Patent: December 16, 2014
    Assignee: TDK Corporation
    Inventors: Takekazu Yamane, Takahiko Machita, Naomichi Degawa, Minoru Ota, Kenta Hamamoto
  • Patent number: 8896974
    Abstract: A thin film magnetic head includes a spin valve film that includes a magnetization free layer, a magnetization pinned layer and a non-magnetic spacer layer that is disposed between the magnetization free and pinned layers, and a pair of side layers that are disposed at both sides of the spin valve film in a track width direction and at least in the vicinity of the magnetization free layer and the magnetization pinned layer. Each of the side layers has a bias magnetic field application layer that includes a soft magnetic layer and applies a bias magnetic field in the track width direction to the magnetization free layer, and a gap layer that is positioned between the spin valve film and the bias magnetic field application layer, and the side layers have compression stresses at least in the vicinity of the magnetization pinned layer.
    Type: Grant
    Filed: March 29, 2013
    Date of Patent: November 25, 2014
    Assignee: TDK Corporation
    Inventors: Shohei Kawasaki, Shuji Okame, Takayasu Kanaya, Satoshi Miura, Kenzo Makino, Takumi Yanagisawa, Takahiko Machita, Masashi Sano, Hideyuki Ukita
  • 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: 8477461
    Abstract: A thin film magnetic head including an MR laminated body composed of a first and second MR magnetic layers, first and second shield layers, and a bias magnetic field application layer provided on an opposite side of an air bearing surface (ABS) of the MR laminated body in order to apply a bias magnetic field orthogonal relative to the ABS. The first shield layer includes a first exchange coupling magnetic field application layer and a first antiferromagnetic layer; and the second shield layer includes a second exchange coupling magnetic field application layer and a second antiferromagnetic layer.
    Type: Grant
    Filed: July 29, 2008
    Date of Patent: July 2, 2013
    Assignee: TDK Corporation
    Inventors: Tsutomu Chou, Yoshihiro Tsuchiya, Shinji Hara, Daisuke Miyauchi, Takahiko Machita
  • Patent number: 8472149
    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: Grant
    Filed: October 1, 2007
    Date of Patent: June 25, 2013
    Assignee: TDK Corporation
    Inventors: Shinji Hara, Daisuke Miyauchi, Koji Shimazawa, Yoshihiro Tsuchiya, Tomohito Mizuno, Takahiko Machita
  • 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: 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
  • Patent number: 8369048
    Abstract: A thin film magnetic head includes a magnetoresistive (MR) stack disposed between first and second shield layers in a direction orthogonal to the film surface; a first exchange-coupling layer that is positioned between the MR stack and the first shield layer; a second exchange-coupling layer that is positioned between the MR stack and the second shield layer; a bias magnetic field application layer that is disposed at an opposite surface of the MR stack from an air bearing surface (ABS); and pair of side shield layers that are positioned at both sides of the MR stack with respect to a track width direction. Each of the side shield layers includes a pair of magnetic layers that are antiferromagnetically exchange-coupled through a side shield ruthenium layer.
    Type: Grant
    Filed: August 31, 2009
    Date of Patent: February 5, 2013
    Assignee: TDK Corporation
    Inventors: Daisuke Miyauchi, Keita Kawamori, Takahiko Machita
  • Patent number: 8310791
    Abstract: A magnetoresistive effect element is structured in the manner that the antiferromagnetic layer interposed between the upper and lower shields is eliminated and the antiferromagnetic layer is positioned in a so-called shield layer. Therefore, it is realized to solve a pin reversal problem and to allow narrower tracks and narrower read gaps.
    Type: Grant
    Filed: March 13, 2009
    Date of Patent: November 13, 2012
    Assignee: TDK Corporation
    Inventors: Takahiko Machita, Tomohito Mizuno, Koji Shimazawa, Tsutomu Chou, Daisuke Miyauchi, Yoshihiro Tsuchiya, Shinji Hara, Toshiyuki Ayukawa
  • 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
  • Patent number: 8256096
    Abstract: Using a beam of xenon ions together with a suitable mask, a stack is ion milled until a part of it, no more than about 0.1 microns thick, has been removed so that a pedestal having sidewalls, including a vertical section and a shortened taper portion, has been formed. This is followed by formation of conductive lead layers as needed. Using xenon as the sputtering gas enables the point at which milling is terminated to be more precisely controlled.
    Type: Grant
    Filed: October 18, 2007
    Date of Patent: September 4, 2012
    Assignees: Headway Technologies, Inc., TDK Corporation
    Inventors: Stuart Kao, Chunping Luo, Chaopeng Chen, Takahiko Machita, Daisuke Miyauchi, Jeiwei Chang
  • Patent number: 8225489
    Abstract: An MR element includes a first exchange coupling shield layer, an MR stack, and a second exchange coupling shield layer that are arranged in this order from the bottom, and a nonmagnetic layer surrounding the MR stack. The MR stack includes a first free layer, a spacer layer, a second free layer, and a magnetic cap layer that are arranged in this order from the bottom. In the step of forming the MR stack and the nonmagnetic layer, a protection layer is formed on a layered film that will be the MR stack later, and a mask is then formed on the protection layer. Next, the layered film and the protection layer are etched using the mask and then the nonmagnetic layer is formed. After removal of the mask, the protection layer is removed by wet etching.
    Type: Grant
    Filed: March 26, 2010
    Date of Patent: July 24, 2012
    Assignee: TDK Corporation
    Inventors: Daisuke Miyauchi, Takahiko Machita, Keita Kawamori