Patents by Inventor Eizo Fukami

Eizo Fukami 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: 6903908
    Abstract: A magnetoresistive effect sensor uses a shielded-type magnetoresistive effect element using a magnetoresistive effect film formed by a basic configuration of a combination of a free layer, a barrier layer formed on the free layer, and a fixed layer formed on the barrier layer, wherein a sensing current flows substantially perpendicular to the magnetoresistive effect film, and wherein an amorphous material or a microcrystalline material is used in a lower shield.
    Type: Grant
    Filed: May 14, 2001
    Date of Patent: June 7, 2005
    Assignee: NEC Corporation
    Inventors: Kazuhiko Hayashi, Keishi Ohashi, Nobuyuki Ishiwata, Masafumi Nakada, Eizo Fukami, Kiyokazu Nagahara, Hiroaki Honjo, Junichi Fujikata, Kunihiko Ishihara, Shigeru Mori
  • Patent number: 6798626
    Abstract: A magnetoresistive effect element which is easy to manufacture and in which a sense current is prevented from bypassing a barrier layer is provided. Also provided are a method for manufacturing the element and a magnetic recording apparatus utilizing the element. This magnetoresistive effect element utilizes an MTJ film which comprises, for forming its basic structure, a free layer, a barrier layer, a pinned layer and a pinning layer, wherein an oxide or a nitride layer is formed by oxidizing or nitriding metallic materials constituting the pinned layer and pinning layer.
    Type: Grant
    Filed: February 3, 2003
    Date of Patent: September 28, 2004
    Assignee: NEC Corporation
    Inventors: Kazuhiko Hayashi, Keishi Ohashi, Nobuyuki Ishiwata, Masafumi Nakada, Eizo Fukami, Kiyokazu Nagahara, Hiroaki Honjou, Shinsaku Saitoh
  • Publication number: 20040134877
    Abstract: In a magnetoresistance apparatus including a first functional layer and a second functional layer magnetically connected to the first functional layer, an overlapping ratio of the second functional layer onto the first functional layer is approximately 0 to 10 percent.
    Type: Application
    Filed: January 5, 2004
    Publication date: July 15, 2004
    Applicant: TDK CORPORATION
    Inventors: Nobuyuki Ishiwata, Shigeru Mori, Kiyokazu Nagahara, Tsutomu Ishi, Kunihiko Ishihara, Eizo Fukami, Masafumi Nakada
  • Patent number: 6718621
    Abstract: In a production process of an MR head using the tunnel junction film basically consisting of a free layer, a barrier layer, and a pinned layer, the resistance between the free layer and the pined layer reduced beforehand and increased afterward up to a resistance value necessary when actually used. While the resistance between the free layer and the pinned layer is low, current can easily flow, suppressing charge up, thus preventing insulation destruction of the barrier layer. This significantly increases a production yield of a recording/reproduction head using a ferromagnetic tunnel junction element.
    Type: Grant
    Filed: May 9, 2000
    Date of Patent: April 13, 2004
    Assignee: NEC Corporation
    Inventors: Kazuhiko Hayashi, Keishi Ohashi, Nobuyuki Ishiwata, Masafumi Nakada, Eizo Fukami, Kiyokazu Nagahara, Hiroaki Honjo, Shinsaku Saitoh
  • Patent number: 6624987
    Abstract: A magnetoresistive effect head which is easy to manufacture and in which a sense current is prevented from bypassing a barrier layer is provided. Also provided are a method for manufacturing the head and a magnetic recording apparatus utilizing the head. This magnetoresistive effect head utilizes an MTJ film which comprises, for forming its basic structure, a free layer, a barrier layer, a pinned layer and a pinning layer, wherein an oxide or a nitride layer is formed by oxidizing or nitriding metallic materials constituting the pinned layer and pinning layer.
    Type: Grant
    Filed: May 31, 2000
    Date of Patent: September 23, 2003
    Assignee: NEC Corporation
    Inventors: Kazuhiko Hayashi, Keishi Ohashi, Nobuyuki Ishiwata, Masafumi Nakada, Eizo Fukami, Kiyokazu Nagahara, Hiroaki Honjou, Shinsaku Saitoh
  • Publication number: 20030151859
    Abstract: A magnetoresistive effect element which is easy to manufacture and in which a sense current is prevented from bypassing a barrier layer is provided. Also provided are a method for manufacturing the element and a magnetic recording apparatus utilizing the element. This magnetoresistive effect element utilizes an MTJ film which comprises, for forming its basic structure, a free layer, a barrier layer, a pinned layer and a pinning layer, wherein an oxide or a nitride layer is formed by oxidizing or nitriding metallic materials constituting the pinned layer and pinning layer.
    Type: Application
    Filed: February 3, 2003
    Publication date: August 14, 2003
    Applicant: NEC CORPORATION
    Inventors: Kazuhiko Hayashi, Keishi Ohashi, Nobuyuki Ishiwata, Masafumi Nakada, Eizo Fukami, Kiyokazu Nagahara, Hiroaki Honjou, Shinsaku Saitoh
  • Patent number: 6538861
    Abstract: A magnetoresistive head whose operation depends on a magnetoresistive effect is configured using a ferromagnetic tunnel junction (MTJ) film, which is arranged between a lower electrode and an upper electrode. The ferromagnetic tunnel junction film is basically configured using a set of a free layer, a barrier layer and a fixing layer, which are sequentially formed and laminated on the lower electrode. Herein, the ferromagnetic tunnel junction film is designed to avoid electrostatic destruction in manufacture by prescribed measures. For example, the barrier layer is reduced in thickness at a terminal portion as compared with a center portion. Or, the barrier layer has a defect at the terminal portion. In addition, it is possible to provide a conductor in connection with the barrier layer in proximity to its terminal portion.
    Type: Grant
    Filed: June 19, 2000
    Date of Patent: March 25, 2003
    Assignee: NEC Corporation
    Inventors: Kazuhiko Hayashi, Masafumi Nakada, Eizo Fukami, Kiyokazu Nagahara, Hiroaki Honjou, Kunihiko Ishihara, Tamaki Toba, Hisanao Tsuge, Atsushi Kamijo
  • Patent number: 6493195
    Abstract: A magnetoresistance element includes a lower electrode layer, a magnetoresistance effect layer, an upper electrode layer and a lower electrode anti-erosion/flaking layer. The lower electrode anti-erosion/flaking layer, which is formed before a photoresist layer remaining on the patterned lower electrode layer is removed, is formed around the lower electrode layer so that its edge facing the lower electrode layer will be in contact with the edge of the lower electrode layer.
    Type: Grant
    Filed: August 30, 2000
    Date of Patent: December 10, 2002
    Assignee: NEC Corporation
    Inventors: Kazuhiko Hayashi, Keishi Ohashi, Nobuyuki Ishiwata, Masafumi Nakada, Eizo Fukami, Hiroaki Honjo, Hisanao Tsuge, Atsushi Kamijo
  • Publication number: 20020008016
    Abstract: A magnetoresistive effect sensor uses a shielded-type magnetoresistive effect element using a magnetoresistive effect film formed by a basic configuration of a combination of a free layer, a barrier layer formed on the free layer, and a fixed layer formed on the barrier layer, wherein a sensing current flows substantially perpendicular to the magnetoresistive effect film, and wherein an amorphous material or a microcrystalline material is used in a lower shield.
    Type: Application
    Filed: May 14, 2001
    Publication date: January 24, 2002
    Inventors: Kazuhiko Hayashi, Keishi Ohashi, Nobuyuki Ishiwata, Masafumi Nakada, Eizo Fukami, Kiyokazu Nagahara, Hiroaki Honjo, Junichi Fujikata, Kunihiko Ishihara, Shigeru Mori