Patents by Inventor Kota Asatsuma

Kota Asatsuma 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: 9207293
    Abstract: A magnetic sensor having no sensitivity differences between sensitivity axes, and an easy manufacturing method therefor are provided. The method includes a process of forming first stacked films for a magnetoresistive element on a substrate. This element has a sensitivity axis in a certain direction and includes a self-pinned ferromagnetic pinned layer in which first and second ferromagnetic films are antiferromagnetically coupled through an antiparallel coupling layer, a nonmagnetic intermediate layer, and a soft magnetic free layer. The method further includes a process of removing a region of the first stacked films from the substrate. The remaining region of the films includes at least a region to be left to form the element. The method furthermore includes a process of forming second stacked films for a magnetoresistive element, which has a sensitivity axis in a direction different from the certain direction and has the same structure, on the exposed substrate.
    Type: Grant
    Filed: May 8, 2012
    Date of Patent: December 8, 2015
    Assignee: ALPS ELECTRIC CO., LTD.
    Inventors: Hideto Ando, Shinji Sugihara, Fumihito Koike, Kota Asatsuma
  • Patent number: 8760913
    Abstract: A magnetic detecting element includes a laminated structure where a fixed magnetic layer and a free magnetic layer are laminated through a non-magnetic material layer, wherein the fixed magnetic layer is a self-pinned type where a first magnetic layer and a second magnetic layer are laminated through a non-magnetic intermediate layer and the first magnetic layer and the second magnetic layer are antiparallelly magnetization-fixed, and the second magnetic layer is in contact with the non-magnetic material layer. The first magnetic layer is formed using FeCo serving as a material having a higher coercive force than the second magnetic layer. The film thickness of the first magnetic layer falls within a range greater than or equal to 10 ? and less than or equal to 17 ?, and is thinner than the film thickness of the second magnetic layer. The non-magnetic intermediate layer is formed using Rh.
    Type: Grant
    Filed: December 7, 2012
    Date of Patent: June 24, 2014
    Assignee: Alps Electric Co., Ltd.
    Inventors: Fumihito Koike, Kota Asatsuma
  • Publication number: 20130257422
    Abstract: A magnetic sensor of the present invention includes a magnetoresistive element having a sensitivity axis in a specified direction, the magnetoresistive element having a laminated structure including a ferromagnetic pinned layer having a pinned magnetization direction, a nonmagnetic intermediate layer, a free magnetic layer having a magnetization direction varying with an external magnetic field, and an antiferromagnetic layer which applies an exchange coupling magnetic field to the free magnetic layer.
    Type: Application
    Filed: May 29, 2013
    Publication date: October 3, 2013
    Inventors: Fumihito KOIKE, Kota ASATSUMA, Masamichi SAITO, Akira TAKAHASHI, Yosuke IDE
  • Publication number: 20130257581
    Abstract: A magnetic detecting element includes a laminated structure where a fixed magnetic layer and a free magnetic layer are laminated through a non-magnetic material layer, wherein the fixed magnetic layer is a self-pinned type where a first magnetic layer and a second magnetic layer are laminated through a non-magnetic intermediate layer and the first magnetic layer and the second magnetic layer are antiparallelly magnetization-fixed, and the second magnetic layer is in contact with the non-magnetic material layer. The first magnetic layer is formed using FeCo serving as a material having a higher coercive force than the second magnetic layer. The film thickness of the first magnetic layer falls within a range greater than or equal to 10 ? and less than or equal to 17 ?, and is thinner than the film thickness of the second magnetic layer. The non-magnetic intermediate layer is formed using Rh.
    Type: Application
    Filed: December 7, 2012
    Publication date: October 3, 2013
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventors: Fumihito KOIKE, Kota ASATSUMA
  • Publication number: 20130009630
    Abstract: A magnetic detection device includes a layered film including a self-pinned magnetic layer, a free magnetic layer, a nonmagnetic material layer disposed between the pinned magnetic layer and the free magnetic layer, and a top capping layer. The pinned magnetic layer includes a first magnetic layer, a second magnetic layer, and a nonmagnetic intermediate layer disposed therebetween. A first magnetization of the first magnetic layer is pinned in antiparallel with a second magnetization of the second magnetic layer. The capping layer is formed of tantalum, and an as-deposited thickness of the capping layer is 55 ? or more.
    Type: Application
    Filed: May 4, 2012
    Publication date: January 10, 2013
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventors: Fumihito KOIKE, Kota ASATSUMA, Kazuya OMINATO
  • Publication number: 20120217962
    Abstract: A magnetic sensor having no sensitivity differences between sensitivity axes, and an easy manufacturing method therefor are provided. The method includes a process of forming first stacked films for a magnetoresistive element on a substrate. This element has a sensitivity axis in a certain direction and includes a self-pinned ferromagnetic pinned layer in which first and second ferromagnetic films are antiferromagnetically coupled through an antiparallel coupling layer, a nonmagnetic intermediate layer, and a soft magnetic free layer. The method further includes a process of removing a region of the first stacked films from the substrate. The remaining region of the films includes at least a region to be left to form the element. The method furthermore includes a process of forming second stacked films for a magnetoresistive element, which has a sensitivity axis in a direction different from the certain direction and has the same structure, on the exposed substrate.
    Type: Application
    Filed: May 8, 2012
    Publication date: August 30, 2012
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventors: Hideto ANDO, Shinji SUGIHARA, Fumihito KOIKE, Kota ASATSUMA
  • Publication number: 20120032673
    Abstract: First magnetoresistive effect elements and second magnetoresistive effect elements and are formed on the same substrate. A pinned magnetic layer of each of the first magnetoresistive effect elements has a three-layer laminated ferrimagnetic structure including magnetic layers. A pinned magnetic layer of each of the second magnetoresistive effect elements has a two-layer laminated ferrimagnetic structure including magnetic layers. The magnetization direction of the third magnetic layer of each of the magnetoresistive effect elements is antiparallel to the magnetization direction of the second magnetic layer of each of the second magnetoresistive effect elements.
    Type: Application
    Filed: October 14, 2011
    Publication date: February 9, 2012
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventors: Shuji MAEKAWA, Kota ASATSUMA, Fumihito KOIKE, Hideto ANDO
  • Patent number: 8009391
    Abstract: An underlying layer is composed of Co—Fe—B that is an amorphous magnetic material. Thus, the upper surface of the underlying layer can be taken as a lower shield layer-side reference position for obtaining a gap length (GL) between upper and lower shields, resulting in a narrower gap than before. In addition, since the underlying layer has an amorphous structure, the underlying layer does not adversely affect the crystalline orientation of individual layers to be formed thereon, and the surface of the underlying layer has good planarizability. Accordingly, PW50 (half-amplitude pulse width) and SN ratio can be improved more than before without causing a decrease in rate of change in resistance (? R/R) or the like, thereby achieving a structure suitable for increasing recording density.
    Type: Grant
    Filed: May 15, 2008
    Date of Patent: August 30, 2011
    Assignee: TDK Corporation
    Inventors: Kenichi Tanaka, Eiji Umetsu, Kazuaki Ikarashi, Kota Asatsuma, Norimasa Okanishi, Yoshihiro Nishiyama, Masamichi Saito, Yosuke Ide, Kazumasa Nishimura, Ryo Nakabayashi, Hidekazu Kobayashi, Akio Hanada, Naoya Hasegawa
  • Publication number: 20080285180
    Abstract: An underlying layer is composed of Co—Fe—B that is an amorphous magnetic material. Thus, the upper surface of the underlying layer can be taken as a lower shield layer-side reference position for obtaining a gap length (GL) between upper and lower shields, resulting in a narrower gap than before. In addition, since the underlying layer has an amorphous structure, the underlying layer does not adversely affect the crystalline orientation of individual layers to be formed thereon, and the surface of the underlying layer has good planarizability. Accordingly, PW50 (half-amplitude pulse width) and SN ratio can be improved more than before without causing a decrease in rate of change in resistance (? R/R) or the like, thereby achieving a structure suitable for increasing recording density.
    Type: Application
    Filed: May 15, 2008
    Publication date: November 20, 2008
    Inventors: Kenichi Tanaka, Eiji Umetsu, Kazuaki Ikarashi, Kota Asatsuma, Norimasa Okanishi, Yoshihiro Nishiyama, Masamichi Saito, Yosuke Ide, Kazumasa Nishimura, Ryo Nakabayashi, Hidekazu Kobayashi, Akio Hanada, Naoya Hasegawa
  • Publication number: 20080174921
    Abstract: A second fixed magnetic layer is formed of a CoFeB layer of CoFeB and an interface layer of CoFe or Co provided in that order from the bottom. An insulating barrier layer composed of Al—O is formed on the second fixed magnetic layer. When a lamination structure composed of CoFeB/CoFe/Al—O is formed as described above, a low RA and a high rate of change in resistance (?R/R) can be simultaneously obtained. In addition, variations in RA and rate of change in resistance (?R/R) can be suppressed as compared to that in the past.
    Type: Application
    Filed: September 21, 2007
    Publication date: July 24, 2008
    Inventors: Kazuaki Ikarashi, Eiji Umetsu, Kenichi Tanaka, Kota Asatsuma
  • Publication number: 20080151438
    Abstract: The invention provides a magnetoresistive element including a seed layer having a flat surface, which makes it possible to improve the flatness of all of the elements. A seed layer is formed in a two-layer structure of a first seed layer that is formed on a lower shield layer and a second seed layer that is formed underneath an anti-ferromagnetic layer, and the second seed layer is formed of ruthenium (Ru). According to this structure, the flatness of the surface of the seed layer is improved, which makes it possible to improve the flatness of interfaces between layers of an element formed on the seed layer. As a result, it is possible to manufacture a magnetoresistive element having a high dielectric breakdown voltage and high operational reliability.
    Type: Application
    Filed: November 28, 2007
    Publication date: June 26, 2008
    Inventors: Kenichi Tanaka, Eiji Umetsu, Kazuaki Ikarashi, Kota Asatsuma