Patents by Inventor Masashi Sahashi

Masashi Sahashi 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: 5712751
    Abstract: Magnetic sensor comprises a pair of hard magnetic films magnetized inplane in directions substantially perpendicular to the direction of a signal magnetic field and substantially equal to each other, a soft magnetic film formed in the same plane as the pair of hard magnetic films and interposed between the pair of hard magnetic films and held in contact therewith or in proximity thereto, and a signal magnetic field detecting film superposed on the main surface of the soft magnetic film. A magnetic recording.reproducing head using this reproducing head comprises the reproducing head mentioned above, a pair of magnetic pole layers vertically opposed to each other through the medium of a recording gap, and a recording head possessed of a recording track width equal to or smaller than the reproducing track width of the reproducing head. The reproducing track width L.sub.1 is so set as to satisfy the relation, L.sub.2 <L.sub.1 <L.sub.3, wherein L.sub.
    Type: Grant
    Filed: January 30, 1997
    Date of Patent: January 27, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroaki Yoda, Masashi Sahashi
  • Patent number: 5702832
    Abstract: It is an object of the present invention to provide a magnetoresistance effect element which has a film with a spin valve structure or an artificial lattice film having good soft magnetic characteristics, and which can be applied to a high-sensitivity magnetic head. The present invention provides a magnetoresistance effect element including a stacked film formed on a substrate by sequentially stacking a ferromagnetic film containing as its main constituents at least one elements selected from the group consisting of Co, Fe, and Ni, a nonmagnetic film, and the ferromagnetic film, wherein the two ferromagnetic films are not coupled with each other, and the closest packed plane of each ferromagnetic film is oriented in a direction perpendicular to the film surface.
    Type: Grant
    Filed: May 23, 1996
    Date of Patent: December 30, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hitoshi Iwasaki, Yuichi Ohsawa, Reiko Kondoh, Susumu Hashimoto, Atsuhito Sawabe, Yuzo Kamiguchi, Masashi Sahashi
  • Patent number: 5698335
    Abstract: It is an object of the present invention to provide a magnetoresistance effect element which has a film with a spin valve structure or an artificial lattice film having good soft magnetic characteristics, and which can be applied to a high-sensitivity magnetic head. The present invention provides a magnetoresistance effect element including a stacked film formed on a substrate by sequentially stacking a ferromagnetic film containing as its main constituents at least one elements selected from the group consisting of Co, Fe, and Ni, a nonmagnetic film, and the ferromagnetic film, wherein the two ferromagnetic films are not coupled with each other, and the closest packed plane of each ferromagnetic film is oriented in a direction perpendicular to the film surface.
    Type: Grant
    Filed: May 23, 1996
    Date of Patent: December 16, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hitoshi Iwasaki, Yuichi Ohsawa, Reiko Kondoh, Susumu Hashimoto, Atsuhito Sawabe, Yuzo Kamiguchi, Masashi Sahashi
  • Patent number: 5688605
    Abstract: It is an object of the present invention to provide a magnetoresistance effect element which has a film with a spin valve structure or an artificial lattice film having good soft magnetic characteristics, and which can be applied to a high-sensitivity magnetic head. The present invention provides a magnetoresistance effect element including a stacked film formed on a substrate by sequentially stacking a ferromagnetic film containing as its main constituents at least one elements selected from the group consisting of Co, Fe, and Ni, a nonmagnetic film, and the ferromagnetic film, wherein the two ferromagnetic films are not coupled with each other, and the closest packed plane of each ferromagnetic film is oriented in a direction perpendicular to the film surface.
    Type: Grant
    Filed: May 23, 1996
    Date of Patent: November 18, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hitoshi Iwasaki, Yuichi Ohsawa, Reiko Kondoh, Susumu Hashimoto, Atsuhito Sawabe, Yuzo Kamiguchi, Masashi Sahashi
  • Patent number: 5601662
    Abstract: There is disclosed a method of introducing magnetic anisotropy into a magnetic material, in which a laser beam is selectively radiated on the surface of a magnetic material to locally heat it, thereby forming a pattern of boundary phases for magnetically dividing a main phase of the magnetic material into a plurality of regions, and magnetic domains of the divided main phase regions are controlled to induce magnetic anisotropy in the main phase regions.
    Type: Grant
    Filed: June 29, 1990
    Date of Patent: February 11, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takahiro Hirai, Tadahiko Kobayashi, Masashi Sahashi
  • Patent number: 5593517
    Abstract: The regenerating material according to the present invention comprises two alloy phases which differ in a content of rare earth elements. Of these alloy phases, a dominant phase in the regenerating material is defined as a main phase, and the other phase is defined as a sub-phase. A plurality of particles, each of which consists of a granular main phase and a sub-phase present on the surface of the main phase, gathers to form an aggregate. Otherwise, a sub-phase present in a main phase in the form of fiber. The refrigerator according to the present invention comprises a regenerator charged with above-mentioned regenerating material, a coolant gas and an expansion means for expanding the coolant gas.
    Type: Grant
    Filed: September 15, 1994
    Date of Patent: January 14, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akiko Saito, Masashi Sahashi, Yoichi Tokai, Akihiko Tsutai, Masami Okamura, Yukiko Nishiyama, Michihiko Inaba
  • Patent number: 5585199
    Abstract: A magnetoresistance effect head is disclosed which is provided with a spin valve film of the three-layer laminate construction comprising a pair of magnetic layers made of a Co-based alloy and a nonmagnetic intermediate layer interposed between the pair of magnetic layers. This magnetoresistance effect head satisfies the expressions, 3.ltoreq.d.sub.1 .ltoreq.7, 3.ltoreq.d.sub.2 .ltoreq.7, and 0.ltoreq. (d.sub.1 -d.sub.2)/d.sub.1 .ltoreq.0.40, wherein d.sub.1 and d.sub.2 stand for the thicknesses (nm) of the pair of magnetic layers (providing d.sub.1 .gtoreq.d.sub.2). A soft magnetic layer of high resistance is disposed contiguously to that of the pair of magnetic layers which has the direction of magnetization thereof varied by an external magnetic layer. The total thickness of this soft magnetic layer and the magnetic layer contiguous thereto is in the range of from 5 to 40 nm.
    Type: Grant
    Filed: September 8, 1994
    Date of Patent: December 17, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yuzo Kamiguchi, Susumu Hashimoto, Hitoshi Iwasaki, Yuichi Ohsawa, Masashi Sahashi
  • Patent number: 5583474
    Abstract: Disclosed herein is a planar magnetic element comprising a substrate, a first magnetic layer arranged over the substrate, a first insulation layer arranged over the first magnetic layer, a planer coil formed of a conductor, having a plurality of turns, arranged over the first insulation layer and having a gap aspect ratio of at least 1, the gap aspect ratio being the ratio of the thickness of the conductor to the gap between any adjacent two of the turns, a second insulation layer arranged over the planar coil, and a second magnetic layer arranged over the second insulation layer. When used as an inductor, the planar magnetic element has a great quality coefficient Q. When used as a transformer, it has a large gain and a high voltage ratio. Since the element is small and thin, it is suitable for use in an integrated circuit, and can greatly contribute to miniaturization of electronic devices.
    Type: Grant
    Filed: May 25, 1994
    Date of Patent: December 10, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tetsuhiko Mizoguchi, Toshiro Sato, Masashi Sahashi, Michio Hasegawa, Hiroshi Tomita, Atsuhito Sawabe
  • Patent number: 5565830
    Abstract: A rare earth-cobalt supermagnetostrictive alloy having a composition represented by the general formula, in atomic fraction: R (Co.sub.1-x Fe.sub.x).sub.x, wherein 0.001.ltoreq.x.ltoreq.0.8, 0.2.ltoreq.z.ltoreq.15, and R is at least one element selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu and is consisting essentially of a cubic system whose easy axis of magnetization is generally <100> or <110> oriented; or R (Co.sub.1-x Fe.sub.x).sub.x, wherein 0.001.ltoreq.x.ltoreq.0.8, 0.2.ltoreq.z.ltoreq.15, and R is at least one element selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Sm, Gd, Dy, Er, Yb, and Lu. Such an alloy exhibits satisfactory magnetostriction in a wide range of temperatures from room temperature to liquid nitrogen temperature.
    Type: Grant
    Filed: November 29, 1993
    Date of Patent: October 15, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masashi Sahashi, Tadahiko Kobayashi
  • Patent number: 5552949
    Abstract: An exchange coupled film is presented, which has an antiferromagnetic film being made of N.sub.100-z Mn.sub.z (where N is at least one selected from the group consisting of Cu, Ru, Rh, Re, Pd, Pt, Ag, Au, Os, and Ir; and 24.ltoreq.z.ltoreq.75) and having a tetragonal crystalline structure or being made of Cr.sub.100-x M.sub.x (where M is at least one selected from the group consisting of elements of group 3b of periodic table, Cu, Ru, Rh, Re, Pt, Pd, Ag, Au, Os, Ir, Mn, Fe, Co, and V; and x is in the range of 0<x<30) and a ferromagnetic film at least part of which is laminated with the antiferromagnetic film. With such an antiferromagnetic film, an exchange coupled film with a good exchange coupling characteristic and high corrosive resistance can be obtained.
    Type: Grant
    Filed: March 2, 1994
    Date of Patent: September 3, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Susumu Hashimoto, Yuzo Kamiguchi, Hitoshi Iwasaki, Atsuhito Sawabe, Masashi Sahashi
  • Patent number: 5549978
    Abstract: It is an object of the present invention to provide a magnetoresistance effect element which has a film with a spin valve structure or an artificial lattice film having good soft magnetic characteristics, and which can be applied to a high-sensitivity magnetic head. The present invention provides a magnetoresistance effect element including a stacked film formed on a substrate by sequentially stacking a ferromagnetic film containing as its main constituents at least one elements selected from the group consisting of Co, Fe, and Ni, a nonmagnetic film, and the ferromagnetic film, wherein the two ferromagnetic films are not coupled with each other, and the closest packed plane of each ferromagnetic film is oriented in a direction perpendicular to the film surface.
    Type: Grant
    Filed: November 1, 1993
    Date of Patent: August 27, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hitoshi Iwasaki, Yuichi Ohsawa, Reiko Kondoh, Susumu Hashimoto, Atsuhito Sawabe, Yuzo Kamiguchi, Masashi Sahashi
  • Patent number: 5527398
    Abstract: The magnetostriction alloys of the present invention are composed basically of Tb--Dy-iron which is partially substituted by at least one element selected from the group consisting of Y, La, Ce, Pr, Nd and Sm, and have been grown in the direction of face index <110> or contain Mn and M element (at least one metallic element selected from the group consisting of C, Mg, Al, Si, Ca, Zr, Y, Ga and B. The magnetostrictive alloy may be formed by melting the constituent materials by high frequency induction dissolution. The molten materials are cast in a heated mold having a temperature gradient. The solidified material may be further treated by hot working.
    Type: Grant
    Filed: October 22, 1993
    Date of Patent: June 18, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomomi Funayama, Tadahiko Kobayashi, Isao Sakai, Masashi Sahashi
  • Patent number: 5493465
    Abstract: A magnetoresistance effect element has a pair of ferromagnetic layers with a middle non-magnetic metallic layer interposed therebetween. The middle non-magnetic metallic layer has lamination structure of non-magnetic metallic thin films formed of at least two kinds of non-magnetic metallic materials. In the lamination structure of the non-magnetic metallic thin film, Fermi energies of the non-magnetic metallic thin films disposed on interface sides of the ferromagnetic layers has a value closer to a Fermi energy in a direction of spin whose electron spin dependent mean free path is long among Fermi energies of the ferromagnetic layers. A non-magnetic metallic thin film is disposed between such two non-magnetic metallic thin films. Difference in Fermi energy between non-magnetic metallic thin films made of two kinds of non-magnetic metallic materials is 0.5 eV or more.
    Type: Grant
    Filed: March 14, 1994
    Date of Patent: February 20, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yuzo Kamiguchi, Susumu Hashimoto, Atsuhito Sawabe, Hitoshi Iwasaki, Masashi Sahashi
  • Patent number: 5482573
    Abstract: A magnetic material with an improved maximum energy product useful for high performance permanent magnet, bond magnet and other applications is disclosed. The magnetic material is expressed in a general formula R1.sub.x R2.sub.y M.sub.100-x-y where R1 is at least one element selected from the rare earth elements, R2 is at least one element selected from elements having an atomic radius in a range of 0.156 to 0.174 nm, M is at least one element selected from Fe and Co and x and y are atomic percent individually defined as x.gtoreq.2, y.gtoreq.0.01 and 4.ltoreq.x+y.ltoreq.20, and M occupying 90 atomic percent or more in the principal phase of the compound.
    Type: Grant
    Filed: October 16, 1992
    Date of Patent: January 9, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinya Sakurada, Takahiro Hirai, Akihiko Tsutai, Masashi Sahashi, Hideo Nagai, Tsutomu Yamashita
  • Patent number: 5480495
    Abstract: Disclosed is a magnetic material which suppresses formation of impurity phase of Fe, Co or Fe-Co alloy, possesses a stable ThMn.sub.12 crystal structure as the principal phase, and is excellent in magnetic properties and lower in cost. Such magnetic material is expressed in a general formula:R1.sub.x R2.sub.y Si.sub.z M.sub.u T.sub.vwhere R1is at least one element selected from Zr and Hf, R2is at least one element selected from rare earth element, M is at least one element selected from C, N and P, T is at least one element selected from Fe and Co, x+y+z+u+v=100, x, y, z, u, v are atomic percent individually defined as 0.1.ltoreq.x.ltoreq.20, 2.ltoreq.y.ltoreq.20, 0.5.ltoreq.z.ltoreq.20, 0.ltoreq.u.ltoreq.20, v.gtoreq.50, and of which principal phase possesses a ThMn.sub.12 crystal structure.
    Type: Grant
    Filed: July 6, 1993
    Date of Patent: January 2, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinya Sakurada, Takahiro Hirai, Akihiko Tsutai, Masashi Sahashi
  • Patent number: 5449416
    Abstract: The extremely low temperature cold accumulating material for use in refrigerators, for example, comprises particles containing at least one kind of rare earth element selected from a group consisting of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb. The proportion of particles each having a particle size of 0.01 to 3 mm is 70% or greater by weight with respect to the whole particles and the proportion of particles each having a shape such that the ratio of the major diameter to the minor diameter is not greater than 5 is 70% or greater by weight with respect to the whole particles. The particles are manufactured by quenching and solidifying a molten metal containing at least one kind of rear earth element described above. The thus manufacured extremely low temperature cold accumulating material is improved in cold accumulating efficiency and is specifically improved in mechanical strength and in chemical stability.
    Type: Grant
    Filed: February 3, 1995
    Date of Patent: September 12, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomohisa Arai, Naoyuki Sori, Masashi Sahashi, Yoichi Tokai
  • Patent number: 5416353
    Abstract: A magnetoresistance effect element is prepared by successively forming one upon the other a first magnetic layer, a P- or N-type semiconductor layer, a second magnetic layer, and a magnetization fixing layer in this order on an insulating substrate. A Schottky junction is formed between the first magnetic layer and the semiconductor layer and between the semiconductor layer and the second magnetic layer. The relative angle between the magnetization direction within the first magnetic layer and the magnetization direction within the second magnetic layer is changed depending on the intensity of the magnetic field, leading to a change in the tunnel conductance.
    Type: Grant
    Filed: September 10, 1993
    Date of Patent: May 16, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yuzo Kamiguchi, Atsuhito Sawabe, Masashi Sahashi, Hitoshi Iwasaki
  • Patent number: 5336337
    Abstract: The magnetostriction alloys of the present invention are composed basically of Tb-Dy-iron which is partially substituted by at least one element selected from the group consisting of Y, La, Cs, Pr, Nd and Sm, and have been grown in the direction of face index <110> or contain Mn and M element (at least one metallic element selected from the group consisting of C, Mg, Al, Si, Ca, Zr, Y, Ga and B. The magnetostrictive alloy may be formed by melting the constituent materials by high frequency induction dissolution. The molten materials are cast in a heated mold having a temperature gradient. The solidified material may be further treated by hot working.
    Type: Grant
    Filed: February 4, 1992
    Date of Patent: August 9, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomomi Funayama, Tadahiko Kobayashi, Isao Sakai, Masashi Sahashi
  • Patent number: 5269854
    Abstract: The present invention provides a regenerative material having a peak specific heat at a low temperature. The material is made of a solid solution of at least two different magnetic type metal compounds, for example, ferromagnetic Er.sub.3 Co and antiferromagnetic Er.sub.3 Ni. From these compounds, the regenerative material Er.sub.3 (Ni,Co) in solid-solution form is produced and the material has a lower magnetic phase transition point than each of the compounds. The regenerative material is utilized for a regenerator of a refrigerator.
    Type: Grant
    Filed: February 4, 1992
    Date of Patent: December 14, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akiko Takahashi, Yoichi Tokai, Masashi Sahashi
  • Patent number: 5260615
    Abstract: A magnetoelastic wave device comprising a substrate, a magnetostrictive film formed over the substrate, a wave generating section, a wave receiving section, and a modulation magnetic field generating section. The magnetostrictive film has an axis of easy magnetization which is substantially <uv0> axis and extends parallel to the major surfaces of the magnetostrictive film.
    Type: Grant
    Filed: June 28, 1991
    Date of Patent: November 9, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masashi Sahashi, Tadahiko Kobayashi, Tetsuhiko Mizoguchi