Patents by Inventor Tatsuya Kishi

Tatsuya Kishi 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: 6590803
    Abstract: A magnetic memory device includes a plurality of magnetoresistive elements arranged on a first plane in a matrix form, a plurality of first writing lines which are arranged on a second plane different from the first plane adjacent to the magnetoresistive elements, a first address decoder which selects a desired one from the plurality of first writing lines, a plurality of second writing lines crossing the plurality of first writing lines on a third plane different from the second plane and having parts adjacent to the plurality of magnetoresistive elements on the second plane and parallel to the plurality of first writing lines, and a second address decoder which selects a desired one from the plurality of second writing lines.
    Type: Grant
    Filed: March 22, 2002
    Date of Patent: July 8, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Saito, Kentaro Nakajima, Masayuki Sagoi, Minoru Amano, Shigeki Takahashi, Tatsuya Kishi
  • Publication number: 20030123283
    Abstract: A highly reliable magnetic memory exhibits enhanced data-holding stability at high storage density in a storage layer of a magnetoresistive effect element used for memory cells. A magnetic memory includes a memory cell array having first wirings, second wirings intersecting the first wirings and memory cells each provided at an intersection area of the corresponding first and second wirings. Each memory cell is selected when the corresponding first and second wirings are selected.
    Type: Application
    Filed: December 27, 2002
    Publication date: July 3, 2003
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Minoru Amano, Tatsuya Kishi, Hiroaki Yoda, Yoshiaki Saito, Shigeki Takahashi, Tomomasa Ueda, Katsuya Nishiyama, Yoshiaki Asao, Yoshihisa Iwata
  • Publication number: 20030104249
    Abstract: A magnetoresistance effect element includes a first ferromagnetic layer (1), insulating layer (3) overlying the first ferromagnetic layer, and second ferromagnetic layer (2) overlying the insulating layer. The insulating layer has formed a through hole (A) having an opening width not larger than 20 nm, and the first and second ferromagnetic layers are connected to each other via the through hole.
    Type: Application
    Filed: September 17, 2002
    Publication date: June 5, 2003
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shiho Okuno, Yuichi Ohsawa, Shigeru Haneda, Yuzo Kamiguchi, Tatsuya Kishi
  • Patent number: 6556473
    Abstract: There is provided a magnetic memory including first and second wirings intersecting each other and disposed apart from each other, a magnetoresistance effect film positioned between the first and second wirings, and a first magnetic film including a first portion facing the magnetoresistance effect film with the first wiring interposed therebetween and a pair of second portions positioned on both sides of the first wiring and magnetically connected to the first portion, each of the first and second portions having either one of a high saturation magnetization soft magnetic material containing cobalt and a metal-nonmetal nano-granular film.
    Type: Grant
    Filed: July 26, 2001
    Date of Patent: April 29, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Saito, Koichiro Inomata, Minoru Amano, Kentaro Nakajima, Masayuki Sagoi, Tatsuya Kishi, Shigeki Takahashi
  • Publication number: 20030062975
    Abstract: A magnetoresistive effect element of a tunnel junction type includes a magnetic multi-layered film (1), ferromagnetic film (3) and intervening insulating film (2) such that a current flows between the magnetic multi-layered film and the ferromagnetic film, tunneling through the insulating film. The magnetic multi-layered film includes a first ferromagnetic layer, second ferromagnetic layer and anti-ferromagnetic layer inserted between the first and second ferromagnetic layers.
    Type: Application
    Filed: September 4, 2002
    Publication date: April 3, 2003
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Tatsuya Kishi, Yoshiaki Saito, Minoru Amano, Shigeki Takahashi, Katsuya Nishiyama
  • Publication number: 20020191451
    Abstract: A magnetoresistance effect devices having a magnetization free layer free to rotate in an applied magnetic field. The magnetization free layer may include first and second ferromagnetic material layers with a nonmagnetic material layer disposed between the two ferromagnetic material layers. Those ferromagnetic materials are antiferromagnetically coupled with each other at a magnetic coupling field J (−3 [kOe]≦J<0 [kOe]) or ferromagnetically coupled with each other. Alternatively, the magnetization free film includes a first ferromagnetic material layer including a center region having a first magnetization and edge regions having a second magnetization different from the first magnetization and a second ferromagnetic material layer including a center region having a third magnetization parallel to the first magnetization and edge regions having a fourth magnetization different from the third magnetization.
    Type: Application
    Filed: March 22, 2002
    Publication date: December 19, 2002
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tatsuya Kishi, Minoru Amano, Yoshiaki Saito, Shigeki Takahashi, Kentaro Nakajima, Masayuki Sagoi
  • Publication number: 20020159203
    Abstract: There is provided a magnetoresistance effect element including a first pinned ferromagnetic layer, a second pinned ferromagnetic layer facing the first pinned ferromagnetic layer, surface regions of the first and second pinned ferromagnetic layer facing each other being different from each other in composition, a free ferromagnetic layer intervening between the first and second pinned ferromagnetic layers, a first tunnel barrier layer intervening between the first pinned ferromagnetic layer and the free ferromagnetic layer, and a second tunnel barrier layer intervening between the second pinned ferromagnetic layer and the free ferromagnetic layer.
    Type: Application
    Filed: March 11, 2002
    Publication date: October 31, 2002
    Inventors: Yoshiaki Saito, Masayuki Sagoi, Minoru Amano, Kentaro Nakajima, Shigeki Takahashi, Tatsuya Kishi
  • Publication number: 20020141232
    Abstract: A magnetic memory device includes a plurality of magnetoresistive elements arranged on a first plane in a matrix form, a plurality of first writing lines which are arranged on a second plane different from the first plane adjacent to the magnetoresistive elements, a first address decoder which selects a desired one from the plurality of first writing lines, a plurality of second writing lines crossing the plurality of first writing lines on a third plane different from the second plane and having parts adjacent to the plurality of magnetoresistive elements on the second plane and parallel to the plurality of first writing lines, and a second address decoder which selects a desired one from the plurality of second writing lines.
    Type: Application
    Filed: March 22, 2002
    Publication date: October 3, 2002
    Inventors: Yoshiaki Saito, Kentaro Nakajima, Masayuki Sagoi, Minoru Amano, Shigeki Takahashi, Tatsuya Kishi
  • Publication number: 20020130339
    Abstract: Magnetoresistance effect devices for attaining magnetically stability and for reducing a switching magnetic field. One of the ferromagnetic layers of the magnetoresistance effect device has a plane shape in which a width of an end portions is wider than a center portion sandwiched by two end portions. The end portions are not symmetrical with respect to an easy magnetization axis or longer axis of the plane shape of ferromagnetic material layer, but are substantially rotationally symmetrical with a center of the plane shape as a pivot. The plane shape may have an S-shape where its magnetic domain is stabilized and the switching magnetic field is reduced. The manufacturing method uses two linear mask patterns intersecting with each other to form sharp corners of a ferromagnetic tunnel junction. An electron beam (EB) drawing may be used to form the S-shape plane.
    Type: Application
    Filed: March 15, 2002
    Publication date: September 19, 2002
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tatsuya Kishi, Shigeki Takahashi, Kentaro Nakajima, Minoru Amano, Masayuki Sagoi, Yoshiaki Saito
  • Publication number: 20020034094
    Abstract: There is provided a magnetic memory including first and second wirings intersecting each other and disposed apart from each other, a magnetoresistance effect film positioned between the first and second wirings, and a first magnetic film including a first portion facing the magnetoresistance effect film with the first wiring interposed therebetween and a pair of second portions positioned on both sides of the first wiring and magnetically connected to the first portion, each of the first and second portions having either one of a high saturation magnetization soft magnetic material containing cobalt and a metal-nonmetal nano-granular film.
    Type: Application
    Filed: July 26, 2001
    Publication date: March 21, 2002
    Inventors: Yoshiaki Saito, Koichiro Inomata, Minoru Amano, Kentaro Nakajima, Masayuki Sagoi, Tatsuya Kishi, Shigeki Takahashi
  • Patent number: 6069820
    Abstract: A discrete energy levels are introduced in a ferromagnetic layer of a magnetic device, and tunnel current flows through a plurality of tunnel junctions. The tunnel junctions are disposed between first and second electrodes and the first ferromagnetic layer is interposed between the two tunnel junctions. Variations of the tunnel current depend on the relationship between magnetization directions of the ferromagnetic layer and another ferromagnetic layer. Tunnel current varies between parallel relation and anti-parallel relation.
    Type: Grant
    Filed: February 10, 1999
    Date of Patent: May 30, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koichiro Inomata, Yoshiaki Saito, Tatsuya Kishi