Patents by Inventor Masayoshi Hiramoto

Masayoshi Hiramoto 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: 6950333
    Abstract: A magnetic memory of the present invention includes two or more memory layers and two or more tunnel layers that are stacked in the thickness direction of the layers. The two or more memory layers are connected electrically in series. A group of first layers includes at least one layer selected from the two or more memory layers. A group of second layers includes at least one layer selected from the two or more memory layers. A resistance change caused by magnetization reversal in the group of first layers differs from a resistance change caused by magnetization reversal in the group of second layers.
    Type: Grant
    Filed: October 24, 2003
    Date of Patent: September 27, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masayoshi Hiramoto, Nozomu Matsukawa, Akihiro Odagawa, Mitsuo Satomi, Yasunari Sugita, Yoshio Kawashima
  • Publication number: 20050174700
    Abstract: The present invention provides a magnetic head having improved characteristics, using a magnetoresistive device in which current flows across the film plane such as a TMR device. In a first magnetic head of the present invention, when the area of a non-magnetic layer is defined as a device cross-section area, and the area of a yoke is defined as a yoke area, viewed along the direction perpendicular to the surface of the substrate over which the yoke and the magnetoresistive device are formed, then the device cross-section area is not less than 30% of the yoke area, so that a resistance increase of the device cross-section area is suppressed. In a second magnetic head of the present invention, a magnetoresistive device is formed on a substrate, and a yoke is provided above a non-magnetic layer constituting the device.
    Type: Application
    Filed: July 22, 2004
    Publication date: August 11, 2005
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masayoshi Hiramoto, Nozomu Matsukawa, Akihiro Odagawa, Kenji Iijima, Hiroshi Sakakima
  • Publication number: 20050163336
    Abstract: A condenser sensor (10) comprises an electrically conductive case (20) having an opening portion (22a) formed therein and an opposing portion (22b) opposing to and spaced apart from the opening portion (22a); a fixed electrode (30) received in the electrically conductive case (20) through the opening portion (22a); an electrically conductive diaphragm (51) accommodated in the electrically conductive case (20), the electrically conductive diaphragm (51) spaced apart from the fixed electrode (30) and opposing to the opening portion (22a); an electrically conductive diaphragm supporting member (52) disposed in the electrically conductive case (20) to support the diaphragm (51); a circuit packaging board (60) disposed in the electrically conductive case (20) to be held in electrical contact with the fixed electrode (30) and the diaphragm (51) respectively through the electrically conductive case (20) and the diaphragm supporting member (52); and deformation protecting member (32) for protecting the opposing porti
    Type: Application
    Filed: April 4, 2003
    Publication date: July 28, 2005
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masayoshi Hiramoto, Kazumoto Doi, Yoshinobu Yasuno, Tatsuhiro Sawada
  • Patent number: 6917492
    Abstract: A magnetoresistive element includes a pair of ferromagnetic layers and a non-magnetic layer arranged between the ferromagnetic layers. At least one of the ferromagnetic layers has a composition expressed by (MxLy)100-zRz at the interface with the non-magnetic layer. The non-magnetic layer includes at least one element selected from the group consisting of B, C, N, O, and P. Here, M is FeaCobNic, L is at least one element selected from the group consisting of Pt, Pd, Ir, and Rh, R is an element that has a lower free energy to form a compound with the element of the non-magnetic layer that is at least one selected from the group consisting of B, C, N, O, and P than does any other element included in the composition as M or L, and a, b, c, x, y, and z satisfy a+b+c=100, a?30, x+y=100, 0<y?35, and 0.1?z?20. This element can provide a high MR ratio. A method for manufacturing a magnetoresistive element includes a first heat treatment process at 200° C. to 330° C.
    Type: Grant
    Filed: June 27, 2003
    Date of Patent: July 12, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Nozomu Matsukawa, Masayoshi Hiramoto, Akihiro Odagawa, Yasunari Sugita, Mitsuo Satomi, Yoshio Kawashima
  • Publication number: 20050135020
    Abstract: The present invention provides a magnetoresistive (MR) element that is excellent in MR ratio and thermal stability and includes at least one magnetic layer including a ferromagnetic material M-X expressed by M100-aXa. Here, M is at least one selected from Fe, Co and Ni, X is expressed by X1bX2c,X3d (X1 is at least one selected from Cu, Ru, Rh, Pd, Ag, Os, Ir, Pt and Au, X2 is at least one selected from Al, Sc, Ti, V, Cr, Mn, Ga, Ge, Y, Zr, Nb, Mo, Hf, Ta, W, Re, Zn and lanthanide series elements, and X3 is at least one selected from Si, B, C, N, O, P and S), and a, b, c and d satisfy 0.05?a?60, 0?b?60, 0?c?30, 0?d?20, and a=b+c+d.
    Type: Application
    Filed: February 16, 2005
    Publication date: June 23, 2005
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yasunari Sugita, Masayoshi Hiramoto, Nozomu Matsukawa, Mitsuo Satomi, Yoshio Kawashima, Akihiro Odagawa
  • Publication number: 20050111147
    Abstract: A magnetoresistive element includes a pair of magnetic layers sandwiching an intermediate layer, at least one of the magnetic layers includes an oxide ferrite having a plane orientation with a (100), (110) or (111) plane. The oxide can be formed by sputtering with an oxide target while applying a bias voltage to a substrate including a plane on which the oxide ferrite is to be formed so as to adjust the amount of oxygen supplied to the oxide ferrite from the target. One of the magnetic layers is a pinned magnetic layer, and the pinned magnetic layer includes at least one non-magnetic film and magnetic films sandwiching the non-magnetic film. The magnetic films can be coupled with one another by magnetostatic coupling or antiferromagnetic coupling, generating negative magnetic coupling. Magnetic shifts are reduced by generating negative coupling. This element also has an improved thermal resistance.
    Type: Application
    Filed: December 28, 2004
    Publication date: May 26, 2005
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Masayoshi Hiramoto, Hiroshi Sakakima, Hideaki Adachi, Nozomu Matukawa, Kenji Iijima, Mitsuo Satomi
  • Patent number: 6887717
    Abstract: A magnetoresistive device including a high-resistivity layer (13), a first magnetic layer (12) and a second magnetic layer (14), the first magnetic layer (12) and the second magnetic layer (14) being arranged so as to sandwich the high-resistivity layer (13), wherein the high-resistivity layer (13) is a barrier for passing tunneling electrons between the first magnetic layer (12) and the second magnetic layer (14), and contains at least one element LONC selected from oxygen, nitrogen and carbon; at least one layer A selected from the first magnetic layer (12) and the second magnetic layer (14) contains at least one metal element M selected from Fe, Ni and Co, and an element RCP different from the metal element M; and the element RCP combines with the element LONC more easily in terms of energy than the metal element M. Accordingly, a novel magnetoresistive device having a low junction resistance and a high MR can be obtained.
    Type: Grant
    Filed: August 19, 2002
    Date of Patent: May 3, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masayoshi Hiramoto, Nozomu Matsukawa, Hiroshi Sakakima, Hideaki Adachi, Akihiro Odagawa
  • Patent number: 6878979
    Abstract: A spin switch that can be driven with voltage. This spin switch includes the following: a ferromagnetic material; a magnetic semiconductor magnetically coupled to the ferromagnetic material; an antiferromagnetic material magnetically coupled to the magnetic semiconductor; and an electrode connected to the magnetic semiconductor via an insulator. A change in the electric potential of the electrode causes the magnetic semiconductor to make a reversible transition between a ferromagnetic state and a paramagnetic state. When the magnetic semiconductor is changed to the ferromagnetic state, the ferromagnetic material is magnetized in a predetermined direction due to the magnetic coupling with the magnetic semiconductor.
    Type: Grant
    Filed: January 18, 2002
    Date of Patent: April 12, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Nozomu Matsukawa, Masayoshi Hiramoto, Akihiro Odagawa, Mitsuo Satomi, Yasunari Sugita
  • Publication number: 20040257712
    Abstract: The present invention provides a magnetic head having improved characteristics, using a magnetoresistive device in which current flows across the film plane such as a TMR device. In a first magnetic head of the present invention, when the area of a non-magnetic layer is defined as a device cross-section area, and the area of a yoke is defined as a yoke area, viewed along the direction perpendicular to the surface of the substrate over which the yoke and the magnetoresistive device are formed, then the device cross-section area is not less than 30% of the yoke area, so that a resistance increase of the device cross-section area is suppressed. In a second magnetic head of the present invention, a magnetoresistive device is formed on a substrate, and a yoke is provided above a non-magnetic layer constituting the device.
    Type: Application
    Filed: July 22, 2004
    Publication date: December 23, 2004
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masayoshi Hiramoto, Nozomu Matsukawa, Akihiro Odagawa, Kenji Iijima, Hiroshi Sakakima
  • Publication number: 20040228046
    Abstract: The present invention provides a magnetoresistive element that includes a pair of magnetic layers and an intermediate layer between the magnetic layers. The intermediate layer contains at least three elements selected from Groups 2 to 17, and the elements include at least one selected from the group consisting of F, O, N, C and B. According to the invention, a magnetoresistive element with high magnetoresistance change ratio and low resistance can be provided. The invention also provides a method for producing a magnetoresistive element. The method includes forming a precursor and forming at least one part of the intermediate layer from the precursor. The precursor is reacted with at least one reactive species selected from the group consisting of oxygen atoms, nitrogen atoms and carbon atoms in a reactive atmosphere containing the reactive species.
    Type: Application
    Filed: June 18, 2004
    Publication date: November 18, 2004
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masayoshi Hiramoto, Akihiro Odagawa, Nozomu Matukawa, Kenji Iijima, Hiroshi Sakakima
  • Publication number: 20040213071
    Abstract: The present invention provides a vertical current-type magneto-resistive element. The element includes an intermediate layer and a pair of magnetic layers sandwiching the intermediate layer, and at least one of a free magnetic layer and a pinned magnetic layer is a multilayer film including at least one non-magnetic layer and magnetic layers sandwiching the non-magnetic layer. The element area defined by the area of the intermediate layer through which current flows perpendicular to the film is not larger than 1000 &mgr;m2.
    Type: Application
    Filed: May 17, 2004
    Publication date: October 28, 2004
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Masayoshi Hiramoto, Nozomu Matukawa, Akihiro Odagawa, Kenji Iijima, Hiroshi Sakakima
  • Patent number: 6798620
    Abstract: A magnetic head including a magnetic substrate for operating as a first electrode, a multi-layer film formed on a portion of the surface of the magnetic substrate an inter-layer insulating layer provided to cover side surfaces of the multi-layer film, a flux guide formed on surfaces of the multi-layer film and inter-layer insulating layers, a non-magnetic conductive layer formed on a surface of the flux guide, and a second electrode formed on a surface of the non-magnetic conductive layer, in which the multi-layer film includes a first magnetic layer formed on a portion of the surface of the magnetic substrate and includes a fixed layer, and a second magnetic layer including a non-magnetic layer formed on a surface of the first magnetic layer and a free layer formed on a surface of the non-magnetic layer.
    Type: Grant
    Filed: May 20, 2003
    Date of Patent: September 28, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masayoshi Hiramoto, Nozomu Matsukawa, Akihiro Odagawa, Hideaki Adachi, Kenji Iijima, Hiroshi Sakakima, Yasunari Sugita
  • Patent number: 6785100
    Abstract: The present invention provides a magnetic head having improved characteristics, using a magnetoresistive device in which current flows across the film plane such as a TMR device. In a first magnetic head of the present invention, when the area of a non-magnetic layer is defined as a device cross-section area, and the area of a yoke is defined as a yoke area, viewed along the direction perpendicular to the surface of the substrate over which the yoke and the magnetoresistive device are formed, then the device cross-section area is not less than 30% of the yoke area, so that a resistance increase of the device cross-section area is suppressed. In a second magnetic head of the present invention, a magnetoresistive device is formed on a substrate, and a yoke is provided above a non-magnetic layer constituting the device.
    Type: Grant
    Filed: April 9, 2001
    Date of Patent: August 31, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masayoshi Hiramoto, Nozomu Matsukawa, Akihiro Odagawa, Kenji Iijima, Hiroshi Sakakima
  • Patent number: 6778425
    Abstract: A magneto-resistive effect memory element according to the present invention includes a first ferromagnetic film; a second ferromagnetic film; a first nonmagnetic film provided between the first ferromagnetic film and the second ferromagnetic film, a first conductive film for generating a magnetic field for causing magnetization inversion in at least one of the first ferromagnetic film and the second ferromagnetic film, the first conductive film not being electrically in contact with the first ferromagnetic film or the second ferromagnetic film; and a second conductive film and a third conductive film for supplying an electric current to the first ferromagnetic film, the first nonmagnetic film, and the second ferromagnetic film. The first ferromagnetic film and the second ferromagnetic film have different magnetization inversion characteristics with respect to the magnetic field, and the first nonmagnetic film contains at least a nitride.
    Type: Grant
    Filed: August 22, 2001
    Date of Patent: August 17, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Akihiro Odagawa, Masayoshi Hiramoto, Nozomu Matsukawa, Hideaki Adachi, Hiroshi Sakakima
  • Patent number: 6778427
    Abstract: A magnetoresistve memory device includes a magnetoresistive element and a wiring for applying a magnetic field to the magnetoresistive element. The wiring includes two or more conductive wires that extend in the same direction. A plurality of conductive wires is used to apply a magnetic field to a single magnetoresistive element, thereby achieving high-speed response and suppressing crosstalk.
    Type: Grant
    Filed: June 26, 2003
    Date of Patent: August 17, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Akihiro Odagawa, Masayoshi Hiramoto, Nozomu Matsukawa
  • Patent number: 6771473
    Abstract: The present invention provides a magnetoresistive element that includes a pair of magnetic layers and an intermediate layer between the magnetic layers. The intermediate layer contains at least three elements selected from Groups 2 to 17, and the elements include at least one selected from the group consisting of F, O, N, C and B. According to the invention, a magnetoresistive element with high magnetoresistance change ratio and low resistance can be provided. The invention also provides a method for producing a magnetoresistive element. The method includes forming a precursor and forming at least one part of the intermediate layer from the precursor. The precursor is reacted with at least one reactive species selected from the group consisting of oxygen atoms, nitrogen atoms and carbon atoms in a reactive atmosphere containing the reactive species.
    Type: Grant
    Filed: January 18, 2002
    Date of Patent: August 3, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masayoshi Hiramoto, Akihiro Odagawa, Nozomu Matukawa, Kenji Iijima, Hiroshi Sakakima
  • Patent number: 6767655
    Abstract: The present invention provides a vertical current-type magneto-resistive element. The element includes an intermediate layer and a pair of magnetic layers sandwiching the intermediate layer, and at least one of a free magnetic layer and a pinned magnetic layer is a multilayer film including at least one non-magnetic layer and magnetic layers sandwiching the non-magnetic layer. The element area defined by the area of the intermediate layer through which current flows perpendicular to the film is not larger than 1000 &mgr;m2.
    Type: Grant
    Filed: August 16, 2001
    Date of Patent: July 27, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masayoshi Hiramoto, Nozomu Matukawa, Akihiro Odagawa, Kenji Iijima, Hiroshi Sakakima
  • Publication number: 20040085807
    Abstract: A magnetic memory of the present invention includes two or more memory layers and two or more tunnel layers that are stacked in the thickness direction of the layers. The two or more memory layers are connected electrically in series. A group of first layers includes at least one layer selected from the two or more memory layers. A group of second layers includes at least one layer selected from the two or more memory layers. A resistance change caused by magnetization reversal in the group of first layers differs from a resistance change caused by magnetization reversal in the group of second layers.
    Type: Application
    Filed: October 24, 2003
    Publication date: May 6, 2004
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Masayoshi Hiramoto, Nozomu Matsukawa, Akihiro Odagawa, Mitsuo Satomi, Yasunari Sugita, Yoshio Kawashima
  • Publication number: 20040086752
    Abstract: The present invention provides a magnetoresistive element that has excellent magnetoresistance characteristics over a conventional magnetoresistive element. The magnetoresistive element is produced by a method including heat treatment at 330° C. or more and characterized in that the longest distance from a centerline of a non-magnetic layer to the interfaces between a pair of ferromagnetic layers and the non-magnetic layer is not more than 10 nm. This element can be produced, e.g., by forming an underlying film on a substrate, heat-treating the underlying film at 400° C. or more, decreasing surface roughness by irradiating the surface of the underlying film with an ion beam, and forming the ferromagnetic layers and the non-magnetic layer. The longest distance is reduced relatively even when M1 (at least one element selected from Tc, Re, Ru, Os, Rh, Ir, Pd, Pt, Cu, Ag and Au) is added to the ferromagnetic layers in the range of 2 nm from the interfaces with the non-magnetic layer.
    Type: Application
    Filed: October 24, 2003
    Publication date: May 6, 2004
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO.
    Inventors: Nozomu Matsukawa, Akihiro Odagawa, Yasunari Sugita, Mitsuo Satomi, Yoshio Kawashima, Masayoshi Hiramoto
  • Publication number: 20040080874
    Abstract: The invention provides a magnetoresistive element in which the pinned magnetic layer includes at least one non-magnetic film and magnetic films sandwiching that non-magneticfilm, and the magnetic films are coupled with one another by magnetostatic coupling via the non-magnetic film. This element has an improved thermal resistance. Furthermore, the invention provides a magnetoresistive element in which the pinned magnetic layer is as described above. The magnetic films can be coupled with one another by magnetostatic coupling or antiferromagnetic coupling generating negative magnetic coupling. In this element, the magnetic field shift is reduced. Furthermore, the invention provides a magnetoresistive element in which at least one of the magnetic layers sandwiching the intermediate layer includes an oxide ferrite having a plane orientation with a (100), (110) or (111) plane. A magnetic field is introduced in a direction of the axis of easy magnetization in the plane.
    Type: Application
    Filed: October 16, 2003
    Publication date: April 29, 2004
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Masayoshi Hiramoto, Hiroshi Sakakima, Hideaki Adachi, Nozomu Matukawa, Kenji Iijima, Mitsuo Satomi