Patents by Inventor Hitoshi Yamanishi

Hitoshi Yamanishi 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: 5917682
    Abstract: A magnetic head includes a back core made of ferrite and a magnetic alloy film arranged in a vicinity of a magnetic gap and having an average composition expressed by TxMyNz wherein T is Fe or Co; M is at least one metal selected from a group consisting of Nb, Zr, Ta, Hf, Cr, W and Mo; N is nitrogen; and x, y and z are atomic percentages holding 65.ltoreq.x.ltoreq.94, 5.ltoreq.y.ltoreq.25, 0<z.ltoreq.20 and x+y+z=100. The head includes an oxygen diffusion prevention part of a higher concentration of nitrogen than included in the whole magnetic alloy film which is provided at the magnetic alloy film at an interfacial part to the ferrite core.
    Type: Grant
    Filed: September 8, 1997
    Date of Patent: June 29, 1999
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hitoshi Yamanishi, Isamu Aokura, Koichi Osano, Yasushi Inoue, Fumio Sakai
  • Patent number: 5626727
    Abstract: A sputtering apparatus uses a plurality of rectangular targets to form a thin film on a substrate, and includes a plurality of magnets disposed along both side edges of each target in such a manner that the polarities of adjacent magnets along the side edges of the targets are opposite, and polarities of the magnets confronting each other across the targets are opposite. The surfaces of at least two targets are inclined to a surface of the substrate at an angle not smaller than 30.degree. and not larger than 60.degree..
    Type: Grant
    Filed: July 20, 1995
    Date of Patent: May 6, 1997
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hitoshi Yamanishi, Isamu Aokura, Masahide Yokoyama, Takahiro Takisawa
  • Patent number: 5609739
    Abstract: A sputtering apparatus for performing sputtering operation by using a rectangular target made of ferromagnetic material, the apparatus includes an electrode in which one first permanent magnet is disposed on each side edge of a front surface of the target, polarities of the first magnets confronting each other with the target interposed between the first magnets are opposite to each other, one second permanent magnet is disposed on each side edge of a rear surface of the target, polarities of the second magnets confronting each other with the target interposed between the second magnets are opposite to each other, and the polarity of each second magnet disposed on the rear surface of the target is the same as that of the first magnet disposed on the front surface of the target.
    Type: Grant
    Filed: December 23, 1994
    Date of Patent: March 11, 1997
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Isamu Aokura, Hitoshi Yamanishi, Youichi Ohnishi, Tanejiro Ikeda
  • Patent number: 5600520
    Abstract: In a laminated magnetic head core, Fe--M--N system soft magnetic thin films (M being at least one element selected from the group consisting of Ta, Nb, Zr, and Hf) and non-magnetic insulating films are alternately laminated. Each of the soft magnetic thin films is 0.2-10 .mu.m thick. Each of the non-magnetic insulating films is 10 through 1000 nm thick. One of the soft magnetic thin films shows high magnetic permeability in a different direction from that of an adjacent soft magnetic thin film via the non-magnetic insulating film within a film surface of the soft magnetic thin film.
    Type: Grant
    Filed: May 16, 1995
    Date of Patent: February 4, 1997
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Isamu Aokura, Kumio Nago, Hitoshi Yamanishi, Hiroshi Sakakima, Youichi Ohnishi
  • Patent number: 5512156
    Abstract: A magnetron sputtering electrode assembly which is used in a sputtering system having a rectangular flat-plate target, includes permanent magnets arranged along the longitudinal edges of the target to pass lines of magnetic forces in parallel to the surface of the rectangular flat-plate target, and a driving device for reversing polarity of the magnets to change by 180 degrees the direction of the lines of magnetic force caused by the permanent magnets passing in parallel to the surface of the rectangular flat-plate target.
    Type: Grant
    Filed: June 24, 1994
    Date of Patent: April 30, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hitoshi Yamanishi, Isamu Aokura, Toshiyuki Suemitsu, Takahiro Takisawa
  • Patent number: 5429731
    Abstract: The present invention relates to a method for forming a layer of isotropic soft magnetic nitride alloy even by means of mass-production apparatus wherein a target size is large in comparison to a distance between a substrate and a target, by using a bias sputtering method wherein a negative bias voltage is continuously applied to a substrate and sputtering is carried out in Ar atmosphere mixed with nitrogen gas or periodically mixed with nitrogen gas. Furthermore, the present invention may include a heat treatment of the soft magnetic nitride alloy layer deposited on the substrate in a temperature of more than 300.degree..degree.C. to less than 800.degree. C. to improve a soft magnetic characteristic.
    Type: Grant
    Filed: July 6, 1993
    Date of Patent: July 4, 1995
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Koichi Osano, Hiroshi Sakakima, Keita Ihara, Mitsuo Satomi, Kumio Nago, Youichi Ohnishi, Kunio Tanaka, Hitoshi Yamanishi
  • Patent number: 5403457
    Abstract: The method of the invention provides a soft magnetic film having a high saturation magnetic flux density and an anisotropy of high magnetic permeability suitable for use in various types of magnetic heads at a high production yield by use of a sputtering apparatus provided with a sputtering electrode, which has permanent magnets arranged above a target 1 mainly of Fe or Co in such a way that lines of magnetic force 3 generated by said permanent magnets are in parallel to the surface of said target 1 and to the center line of said target 1 and have a magnetic strength pattern symmetric with respect to said center line while the lines of magnetic force to the right of said center line are of a reverse direction to those to the left of said center line.
    Type: Grant
    Filed: August 24, 1993
    Date of Patent: April 4, 1995
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kumio Nago, Isamu Aokura, Hitoshi Yamanishi, Koichi Osano, Hiroshi Sakakima, Toshiyuki Suemitsu
  • Patent number: 5322605
    Abstract: A reactive sputtering apparatus includes a vacuum chamber, a cathode fixed to an inner surface of the chamber, a power source for applying a voltage to the cathode, a magnetic circuit, installed in the cathode and having magnets for generating a magnetic field, a target, installed adjacent the magnets, having an opening at a portion corresponding to a region between the magnets of the magnetic circuit, a vacuum device for evacuating air inside the chamber to obtain vacuum, a first gasintroducing device, disposed at a wall of the chamber, for supplying reactive gas into the chamber, a second gas-introducing device for supplying discharge gas from the opening of the target into the chamber, a first gas flow rate control device for controlling the supply of the reactive gas, a second gas flow rate control device for controlling the supply of the discharge gas, and a substrate holder, disposed in opposition to the target inside the chamber, for securing a substrate thereto.
    Type: Grant
    Filed: September 10, 1992
    Date of Patent: June 21, 1994
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Hitoshi Yamanishi