Patents by Inventor Shigeru Shouji

Shigeru Shouji 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: 6061897
    Abstract: A first resist mask is formed on a rail, covering an area where none of a shallow surface and a deep surface are formed. A first etching process is performed to etch the rail not covered with the first resist mask to a depth corresponding to the shallow surface. Next, without removing the first resist mask, a second resist mask is formed covering an area where the shallow surface is formed. A second etching process is performed to etch the rail not covered with the first and second resist masks, to a depth corresponding to the deep surface. After the first and second etching processes, the first and second resist masks are removed from the rail.
    Type: Grant
    Filed: June 15, 1998
    Date of Patent: May 16, 2000
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Masahiro Sugiura
  • Patent number: 6033580
    Abstract: On a substrate, a lower pole is formed being embedded in a protective film on which a gap layer is formed. On this gap layer, a first upper pole is formed facing the lower pole. A protective film is formed coplanar to the upper surface of the first upper pole. On this protective film, a coil made of a plurality of coil layers is formed being embedded in an insulating film. On the insulating film, an upper core layer is formed whose tip portion constitutes a second upper pole stacked upon the first upper pole and magnetically coupled thereto. The first upper pole formed before the coil is formed and the second upper pole formed after the coil is formed, constitute an upper pole.
    Type: Grant
    Filed: December 30, 1997
    Date of Patent: March 7, 2000
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Shuichi Sawada
  • Patent number: 6010753
    Abstract: The leading edge of a lower pole is constituted by a protruded central parallel portion, opposite end parallel portions, and slanted portions coupling the central parallel portion and the opposite end parallel portions. The width T.sub.wc of the central parallel portion is set to 10 to 25% of the total width T.sub.wa of the lower pole. The thickness P1' of the opposite end portion is set in the range from 1/3 or thicker to 2/3 or thinner than the thickness P19 of the central parallel portion.
    Type: Grant
    Filed: January 28, 1998
    Date of Patent: January 4, 2000
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Atsushi Toyoda
  • Patent number: 5978187
    Abstract: The leading edge of a lower pole is constituted by a protruded central parallel portion, opposite end parallel portions, and slanted portions coupling the central parallel portion and the opposite end parallel portions. The width T.sub.wc of the central parallel portion is set to 10 to 25% of the total width T.sub.wa of the lower pole. The thickness P1' of the opposite end portion is set in the range from 3/1 or thicker to 3/2 or thinner than the thickness P1 of the central parallel portion.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: November 2, 1999
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Atsushi Toyoda
  • Patent number: 5943763
    Abstract: A thin film magnetic head made of material having the magneto-resistance (MR) effect and its manufacturing method are provided. A lower shield layer for magnetically shielding an MR film is formed with a trench of a gull-wing shape having a flat bottom surface and opposite slanted surfaces formed on both sides of the bottom surface. The MR film is formed on the lower shield layer conformal to the gull-wing shape. The region of the MR film on the flat bottom surface forms an effective magnetic active region. A track center shift and the generation of a side-lobe in the off-track characteristic specific to an MR head can be suppressed and high density recording and reproducing of narrow tracks are possible.
    Type: Grant
    Filed: April 22, 1997
    Date of Patent: August 31, 1999
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Atsushi Toyoda
  • Patent number: 5926348
    Abstract: A magneto-resistance type magnetic head having: a base; a longitudinal bias portion, formed over the base and having a first upper flat surface and a first slanted portion, for generating a longitudinal bias magnetic field; a lead portion laminated directly on the longitudinal bias portion so as to cover the first upper flat portion and to expose the first slanted portion of the longitudinal bias portion, wherein the lead portion is made of non-magnetic material and has a second upper flat surface and a second slanted portion, and wherein the first and second slanted portions collectively serve as a slanted surface; and a magneto-resistance material layer formed over the longitudinal bias portion and the lead portion, wherein the magneto-resistance material layer directly contacts an upper surface of the base and magnetically couples with the exposed longitudinal bias portion through the slanted surface of the longitudinal bias portion, wherein the magneto-resistance material layer is terminated on the slante
    Type: Grant
    Filed: August 27, 1997
    Date of Patent: July 20, 1999
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Atsushi Toyoda
  • Patent number: 5907459
    Abstract: A lower shield has an area smaller than an upper shield. A lead is constituted of a thin lead portion and a thick lead portion, the thin lead portion being formed in a reproduction gap between the upper and lower magnetic shield layers and the thick lead portion being formed spaced apart from the end of the lower magnetic shield layer in the depth direction and extending downward in the thickness direction at a level lower than the thin lead portion. The upper surface of the lead is not formed with a step. The thin and thick lead portions are connected via a contact hole formed through a lower reproduction gap layer.
    Type: Grant
    Filed: January 22, 1998
    Date of Patent: May 25, 1999
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Atsushi Toyoda
  • Patent number: 5903968
    Abstract: Thin film magnetic heads each having non-parallel asymmetric rails are manufactured by, forming a multiplicity of thin film magnetic transducers on a substrate, for a matrix distribution of magnetic heads to be produced from the substrate; testing all the magnetic transducers and discriminating them into good ones and failed ones; assigning a rail pattern to each of the magnetic heads, which pattern utilizes a good magnetic transducer; severing the substrate into respective rows; polishing an air bearing surface on each row; forming a resist layer on the air bearing surface of each row; positioning the rows in an exposing apparatus; exposing the assigned rail pattern on the resist layer in each magnetic head region of each row.
    Type: Grant
    Filed: March 23, 1995
    Date of Patent: May 18, 1999
    Assignee: Yamaha Corporation
    Inventor: Shigeru Shouji
  • Patent number: 5880910
    Abstract: On a lower magnetic shield film, a lower gap film is formed on which a conductive lead film and a magnet film is laminated. The magnet film forms a bias permanent magnet film for generating a single magnetic domain of a magneto-resistance film. This lead film is trenched to the lower gap layer (20) to form a trapezoid trench and separated leads. A sensor unit having the magneto-resistance film is formed conformally to the trench and electrically connected to the separated leads. An upper gap is formed on the sensor unit (28), and an upper shield is formed on the upper gap.
    Type: Grant
    Filed: March 20, 1997
    Date of Patent: March 9, 1999
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Atsushi Toyoda
  • Patent number: 5831801
    Abstract: On a substrate, a lower pole is formed being embedded in a protective film on which a gap layer is formed. On this gap layer, a first upper pole is formed facing the lower pole. A protective film is formed coplanar to the upper surface of the first upper pole. On this protective film, a coil made of a plurality of coil layers is formed being embedded in an insulating film. On the insulating film, an upper core layer is formed whose tip portion constitutes a second upper pole stacked upon the first upper pole and magnetically coupled thereto. The first upper pole formed before the coil is formed and the second upper pole formed after the coil is formed, constitute an upper pole.
    Type: Grant
    Filed: January 21, 1997
    Date of Patent: November 3, 1998
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Shuichi Sawada
  • Patent number: 5809636
    Abstract: A lower shield has an area smaller than an upper shield. A lead is constituted of a thin lead portion and a thick lead portion, the thin lead portion being formed in a reproduction gap between the upper and lower magnetic shield layers and the thick lead portion being formed spaced apart from the end of the lower magnetic shield layer in the depth direction and extending downward in the thickness direction at a level lower than the thin lead portion. The upper surface of the lead is not formed with a step. The thin and thick lead portions are connected via a contact hole formed through a lower reproduction gap layer.
    Type: Grant
    Filed: May 21, 1997
    Date of Patent: September 22, 1998
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Atsushi Toyoda
  • Patent number: 5799388
    Abstract: Thin film magnetic heads each having non-parallel asymmetric rails are manufactured by, forming a multiplicity of thin film magnetic transducers on a substrate, for a matrix distribution of magnetic heads to be produced from the substrate; testing all the magnetic transducers and discriminating them into good ones and failed ones; assigning a rail pattern to each of the magnetic heads, which pattern utilizes a good magnetic transducer; severing the substrate into respective rows; polishing an air bearing surface on each row; forming a resist layer on the air bearing surface of each row; positioning the rows in an exposing apparatus; exposing the assigned rail pattern on the resist layer in each magnetic head region of each row.
    Type: Grant
    Filed: November 18, 1996
    Date of Patent: September 1, 1998
    Assignee: Yamaha Corporation
    Inventor: Shigeru Shouji
  • Patent number: 5734536
    Abstract: A lower pole gradually increases its thickness in a section from the pole front end surface toward the depth direction. An upper pole gradually increases its thickness in a section from the pole front end surface toward the depth direction. The lower pole has a constriction at an area deeper than the gradually increasing section.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: March 31, 1998
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Atsushi Toyoda
  • Patent number: 5722157
    Abstract: In an induction- and MR-type composite magnetic head of the type that one of two shield films of an MR-type magnetic head serves as one of two cores of an induction-type magnetic head, conductive leads are thicker than an MR element so that steps are formed at the boundaries between an MR element sensitive region and the conductive leads. An upper gap layer has a constant thickness and has a recess 56 on its upper surface because of topographical transfer of the underlying steps. An upper shield--lower core layer has a downward convex at its lower surface, because of topographical transfer of the recess on the upper surface of the upper gap layer. However, the upper surface of the upper shield--lower core layer is flat and parallel to the MR element. Therefore, a write gap layer formed thereon is made flat and parallel to the MR element. Steps of the write gap can be removed and a record density can be increased.
    Type: Grant
    Filed: June 25, 1996
    Date of Patent: March 3, 1998
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Atsushi Toyoda
  • Patent number: 5668686
    Abstract: A thin film magnetic head made of material having the magneto-resistance (MR) effect and its manufacturing method are provided. A lower shield layer for magnetically shielding an MR film is formed with a trench of a gull-wing shape having a flat bottom surface and opposite slanted surfaces formed on both sides of the bottom surface. The MR film is formed on the lower shield layer conformal to the gull-wing shape. The region of the MR film on the flat bottom surface forms an effective magnetic active region. A track center shift and the generation of a side-lobe in the off-track characteristic specific to an MR head can be suppressed and high density recording and reproducing of narrow tracks are possible.
    Type: Grant
    Filed: December 28, 1995
    Date of Patent: September 16, 1997
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Atsushi Toyoda
  • Patent number: 5559653
    Abstract: A thin film magnetic head includes a lower core portion provided on a substrate and having a pole portion, a magnetic gap layer provided on the lower core portion, an insulating layer provided on the magnetic gap layer, conduction coils provided in the insulating layer, an upper core portion provided on the insulating layer, and an overcoat layer provided on the upper core portion. The upper core portion has a pole portion of a reduced width and a non-pole portion having a top-forming portion and an inclined section-forming portion formed on an inclined section of the insulating layer.
    Type: Grant
    Filed: December 2, 1994
    Date of Patent: September 24, 1996
    Assignee: Yamaha Corporation
    Inventors: Shigeru Shouji, Atsushi Toyoda