Patents by Inventor Tomomi Funayama

Tomomi Funayama 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: 7463455
    Abstract: A magnetic head provided with magnetoresistance effect element, the magnetic head comprises first shielding layer superimposed on one surface of the magnetoresistance effect element and whose area is larger than that of this one surface, a first lead layer formed ranging from a portion where the first shielding layer is superimposed on the magnetoresistance effect element to another portion on the first shielding layer and which applies the sense current to the magnetoresistance effect element, a second shielding layer superimposed on another surface of the magnetoresistance effect element opposite to the one surface and whose area is larger than that of the other surface, and a second lead layer formed ranging from a portion where the second shielding layer is superimposed on the magnetoresistance effect element to another portion on the second shielding layer and which applies the sense current to the magnetoresistance effect element.
    Type: Grant
    Filed: August 10, 2005
    Date of Patent: December 9, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tomomi Funayama
  • Publication number: 20080239588
    Abstract: A magneto-resistance effect element includes a magneto-resistance effect film comprised of a free magnetization layer, a fixed magnetization layer and an intermediate layer disposed between the free magnetization layer and the fixed magnetization layer; a magnetic coupling layer which is disposed on one main surface of the fixed magnetization layer; a ferromagnetic layer which is disposed on one main surface of the magnetic coupling layer; an antiferromagnetic layer which is disposed on one main surface of the ferromagnetic layer; a magnetic domain controlling film for applying a biasing magnetic field to the free magnetization layer; and a pair of electrodes for flowing a current in the magneto-resistance effect film; wherein an asymmetry is set positive and an element resistance RA is set to 1.5 ??m2 or less in the direction from the free magnetization layer to the fixed magnetization layer.
    Type: Application
    Filed: March 14, 2008
    Publication date: October 2, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Masahiro Takashita, Tomomi Funayama, Masayuki Takagishi, Hitoshi Iwasaki
  • Patent number: 7405906
    Abstract: A magnetoresistance effect element of the dual spin valve type using a current-perpendicular-to-the-plane (CPP) system where a sensing current flows perpendicular to the stacked faces of a plurality of conductive layers, the magnetoresistance effect element comprises a first unit which includes a free layer and a first pinning layer, a second unit which includes the free layer shared with the first unit and a second pinning layer, a first current control layer which is provided in the first unit and limits the flow quantity of the sensing current, and a second current control layer which is provided in the second unit and limits the flow quantity of the sensing current.
    Type: Grant
    Filed: September 9, 2004
    Date of Patent: July 29, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomomi Funayama, Masayuki Takagishi, Katsuhiko Koui, Kohichi Tateyama
  • Publication number: 20080144228
    Abstract: According to one embodiment, a magnetic head includes a magnetoresistance element including a first spin valve layer, a bias layer, and a second spin valve layer sequentially arranged in the track direction, the first spin valve layer having a first magnetization free layer including a ferromagnetic film, the second spin valve layer having a second magnetization free layer having a ferromagnetic film, and the bias layer having a magnetic layer to apply a bias magnetic field, in a direction of track width orthogonal to the track direction, to the first magnetization free layer and the second magnetization free layer, and a pair of electrodes to cause a current, having a direction almost parallel to the track direction, to flow into the magnetoresistance element.
    Type: Application
    Filed: December 13, 2007
    Publication date: June 19, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Tomomi Funayama
  • Publication number: 20080106825
    Abstract: A magnetoresistance effect element of the dual spin valve type using a current-perpendicular-to-the-plane (CPP) system where a sensing current flows perpendicular to the stacked faces of a plurality of conductive layers, the magnetoresistance effect element comprises a first unit which includes a free layer and a first pinning layer, a second unit which includes the free layer shared with the first unit and a second pinning layer, a first current control layer which is provided in the first unit and limits the flow quantity of the sensing current, and a second current control layer which is provided in the second unit and limits the flow quantity of the sensing current.
    Type: Application
    Filed: December 27, 2007
    Publication date: May 8, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tomomi Funayama, Masayuki Takagishi, Katsuhiko Koui, Kohichi Tateyama
  • Publication number: 20080106826
    Abstract: A magnetoresistance effect element of the dual spin valve type using a current-perpendicular-to-the-plane (CPP) system where a sensing current flows perpendicular to the stacked faces of a plurality of conductive layers, the magnetoresistance effect element comprises a first unit which includes a free layer and a first pinning layer, a second unit which includes the free layer shared with the first unit and a second pinning layer, a first current control layer which is provided in the first unit and limits the flow quantity of the sensing current, and a second current control layer which is provided in the second unit and limits the flow quantity of the sensing current.
    Type: Application
    Filed: December 27, 2007
    Publication date: May 8, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tomomi Funayama, Masayuki Takagishi, Katsuhiko Koui, Kohichi Tateyama
  • Publication number: 20070291421
    Abstract: Disclosed is a CCP-CPP-GMR head assembly which has: a CCP-CPP-GMR head that includes at least a current control layer having as a microstructure a plurality of truncated cone electric conductors with axes the same as a current direction and an insulator filling between the plurality of truncated cone electric conductors, and in which a surface on which a larger-area basal plane of the plurality of truncated cone electric conductors is greater in number is a first surface of the current control layer and a surface of an opposite side of the first surface is a second surface of the current control layer; and a sense current source providing the CCP-CPP-GMR head with a sense current that flows from the second surface to the first surface, a magnetic recording/reproducing apparatus having such a head, and a specification method of an appropriate sense current direction of the CCP-CPP-GMR head.
    Type: Application
    Filed: August 7, 2007
    Publication date: December 20, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: TOMOMI FUNAYAMA, KOHICHI TATEYAMA, MASAYUKI TAKAGISHI
  • Publication number: 20070279810
    Abstract: According to one embodiment, a current-perpendicular-to-plane magnetic head includes a magnetoresistive film including a pinned layer, an intermediate layer and a free layer, a pair of magnetic shields serving as electrodes provided over and under the magnetoresistive film, and a pair of biasing films provided on both sides of the magnetoresistive film through an insulating film, in which an angle ? between a magnetization direction of the pinned layer and a magnetization direction of the free layer is set to 5°??<90°, or a bias point is set to 5%?BP<50%, at zero external field.
    Type: Application
    Filed: May 31, 2007
    Publication date: December 6, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tomomi Funayama, Katsuhiko Koui
  • Patent number: 7304825
    Abstract: Disclosed is a CCP-CPP-GMR head assembly which has: a CCP-CPP-GMR head that includes at least a current control layer having as a microstructure a plurality of truncated cone electric conductors with axes the same as a current direction and an insulator filling between the plurality of truncated cone electric conductors, and in which a surface on which a larger-area basal plane of the plurality of truncated cone electric conductors is greater in number is a first surface of the current control layer and a surface of an opposite side of the first surface is a second surface of the current control layer; and a sense current source providing the CCP-CPP-GMR head with a sense current that flows from the second surface to the first surface, a magnetic recording/reproducing apparatus having such a head, and a specification method of an appropriate sense current direction of the CCP-CPP-GMR head.
    Type: Grant
    Filed: November 12, 2004
    Date of Patent: December 4, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomomi Funayama, Kohichi Tateyama, Masayuki Takagishi
  • Publication number: 20070268626
    Abstract: According to one embodiment, a perpendicular magnetic recording head includes a main pole which generates a recording magnetic field, a return pole which forms a closed magnetic circuit for the recording magnetic field, and a side shield magnetically spaced from the main pole in a cross-track direction in which a point on a trailing edge of the side shield which is closest to the main pole is positioned on a leading side of a trailing edge of the main pole.
    Type: Application
    Filed: May 3, 2007
    Publication date: November 22, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tomoko Taguchi, Tomomi Funayama, Yuka Aoyagi, Katsuhiko Koui
  • Patent number: 7277262
    Abstract: A magnetic recording/reproducing apparatus has a magnetoresistive head having a magnetoresistive film through which a current is flowed in a direction substantially perpendicular to a film plane and a pair of magnetic shields disposed to sandwich the magnetoresistive film, and a preamplifier which supplies a sense current to the magnetoresistive head in constant-current driving.
    Type: Grant
    Filed: September 2, 2004
    Date of Patent: October 2, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masayuki Takagishi, Tomomi Funayama, Yoichiro Tanaka
  • Patent number: 7196877
    Abstract: A magnetoresistive element includes a magnetoresistive film having a magnetization pinned layer, a magnetization free layer, and a nonmagnetic intermediate layer. A magnetization direction of the magnetization pinned layer is substantially fixed in an external magnetic field, a magnetization direction of the magnetization free layer is configured to change in the external magnetic field, and the nonmagnetic intermediate layer formed between the magnetization pinned layer and the magnetization free layer and has a stacked structure of a first non-metallic intermediate layer/a metal intermediate layer/a second non-metallic intermediate layer. The magnetoresistive element also includes a pair of electrodes coupled to the magnetoresistive film and is configured to provide a current in a direction substantially perpendicular to a surface of the magnetoresistive film.
    Type: Grant
    Filed: December 23, 2003
    Date of Patent: March 27, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masatoshi Yoshikawa, Masayuki Takagishi, Tomomi Funayama, Kohichi Tateyama, Hitoshi Iwasaki, Hideaki Fukuzawa
  • Patent number: 7126795
    Abstract: A magnetic recording head, a magnetic reproducing head, a magnetic recording apparatus comprising the magnetic recording head, and a magnetic reproducing apparatus comprising the magnetic reproducing head are described. The magnetic reproducing head having a magnetic gap at a medium-facing surface and includes a pair of magnetic yokes of ferromagnetic material, a magnetoresistance effect film, and a pair of biasing films. One of the pair of magnetic yokes has a magnetic tip at the medium-facing surface and also a rear portion recessed from the medium-facing surface and magnetically coupled to the magnetic tip. The magnetic tip has a first width in a track width direction at the medium-facing surface, and the rear portion has a second width in the track width direction wider than the first width. The magnetoresistance effect film is recessed from the medium-facing surface and is magnetically coupled to the pair of magnetic yokes of ferromagnetic material.
    Type: Grant
    Filed: August 27, 2001
    Date of Patent: October 24, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomomi Funayama, Kohichi Tateyama, Michiko Hara, Masatoshi Yoshikawa, Hiroaki Yoda
  • Publication number: 20060221484
    Abstract: A magnetic disk apparatus with a magnetic disk medium capable of recording data magnetically, comprises a current perpendicular to plane magnetic reproducing head which includes a magnetoresistive effect element composed of a plurality of magnetic films stacked one on top of another and causes sense current to flow in the direction perpendicular to the stacked faces of the plurality of magnetic films, a high-pass filter which suppresses the low-frequency component of a reproduced signal output from the magnetic reproducing head, and a reproduced-signal processing section which reproduces the data from the reproduced signal which has the low-frequency component suppressed.
    Type: Application
    Filed: March 21, 2006
    Publication date: October 5, 2006
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Tomomi Funayama
  • Publication number: 20060209472
    Abstract: A magnetoresistive device includes a magnetoresistive film and a pair of electrodes for applying a sense current substantially perpendicularly to the magnetoresistive film. The magnetoresistive film includes a magnetization pinned film including a first ferromagnetic layer having a magnetization direction substantially pinned in one direction, a magnetization free film including a second ferromagnetic layer whose magnetization direction changes in accordance with an external magnetic field applied thereto, an intermediate layer formed between the magnetization pinned film and the magnetization free film and having an insulating film and a metal conduction portion extending in the film thickness direction of the insulating film, and a layer containing an electrovalent or covalent compound formed near the metal conduction portion.
    Type: Application
    Filed: March 8, 2006
    Publication date: September 21, 2006
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Katsuhiko Koui, Kohichi Tateyama, Tomomi Funayama, Koichi Kubo, Hitoshi Iwasaki, Hideaki Fukuzawa
  • Patent number: 7100267
    Abstract: A method for producing a magnetic head, including the steps of forming a magnetic body on a substrate, the magnetic body including a principal plane facing the substrate and a rear plane opposite to the principal plane; applying a beam to the rear plane of the magnetic body and forming a portion defining a hole extending from the rear plane to the principal plane; forming a magnetic gap in the hole; and separating the magnetic body and the magnetic gap from the substrate and forming medium facing surface substantially coplanar with the principal plane.
    Type: Grant
    Filed: August 7, 2003
    Date of Patent: September 5, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroaki Yoda, Yuichi Osawa, Tomomi Funayama
  • Publication number: 20060044701
    Abstract: A magnetic head provided with magnetoresistance effect element, the magnetic head comprises first shielding layer superimposed on one surface of the magnetoresistance effect element and whose area is larger than that of this one surface, a first lead layer formed ranging from a portion where the first shielding layer is superimposed on the magnetoresistance effect element to another portion on the first shielding layer and which applies the sense current to the magnetoresistance effect element, a second shielding layer superimposed on another surface of the magnetoresistance effect element opposite to the one surface and whose area is larger than that of the other surface, and a second lead layer formed ranging from a portion where the second shielding layer is superimposed on the magnetoresistance effect element to another portion on the second shielding layer and which applies the sense current to the magnetoresistance effect element.
    Type: Application
    Filed: August 10, 2005
    Publication date: March 2, 2006
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Tomomi Funayama
  • Patent number: 6940700
    Abstract: In a magnetic head having magnetic yoke layers, each magnetic yoke layer includes a yoke projecting portion (2A) projected toward a recording medium, and yoke setback portions (2B) set back from the yoke projecting portion. A first bias magnetic field applying film (5) of an antiferromagnetic material is formed to cover the yoke projecting portion whereas a second bias magnetic field applying film (6) of a ferromagnetic material may be formed on opposite side surfaces of the yoke projecting portion.
    Type: Grant
    Filed: June 24, 2002
    Date of Patent: September 6, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kohichi Tateyama, Susumu Hashimoto, Masayuki Takagishi, Tomomi Funayama, Yuichi Ohsawa
  • Publication number: 20050190510
    Abstract: Disclosed is a CCP-CPP-GMR head assembly which has: a CCP-CPP-GMR head that includes at least a current control layer having as a microstructure a plurality of truncated cone electric conductors with axes the same as a current direction and an insulator filling between the plurality of truncated cone electric conductors, and in which a surface on which a larger-area basal plane of the plurality of truncated cone electric conductors is greater in number is a first surface of the current control layer and a surface of an opposite side of the first surface is a second surface of the current control layer; and a sense current source providing the CCP-CPP-GMR head with a sense current that flows from the second surface to the first surface, a magnetic recording/reproducing apparatus having such a head, and a specification method of an appropriate sense current direction of the CCP-CPP-GMR head.
    Type: Application
    Filed: November 12, 2004
    Publication date: September 1, 2005
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tomomi Funayama, Kohichi Tateyama, Masayuki Takagishi
  • Publication number: 20050094317
    Abstract: A CPP (Current Perpendicular-to-the-Plane) magnetoresistance effect element which causes sensing current to flow perpendicularly to the stacked faces of a plurality of conductive layers, the CPP magnetoresistance effect element comprises a composite layer in which a plurality of regions differing from one another are formed in a common layer in a mixed manner and which includes a current control region which is formed narrower than the stacked area of the composite layer and controls the flow rate of the sensing current, and an insulating material region which cuts off the flow of the sensing current.
    Type: Application
    Filed: September 22, 2004
    Publication date: May 5, 2005
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Tomomi Funayama