Patents by Inventor Kiyoaki Tsumura

Kiyoaki Tsumura 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: 6907053
    Abstract: A semiconductor laser element and a protective wall surrounding the element are provided on the surface of a metal frame of a semiconductor laser device. Circumferential portions are provided on an outer periphery of the metal frame for rotating the optical axis of light originating from a light-emitting point of the semiconductor laser element to a direction along the surface of the metal frame. By way of a guide of an optical pickup base corresponding to the circumferential portions, the semiconductor laser device is mounted on the optical pickup base.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: June 14, 2005
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Mitsumi Electric Co., Ltd.
    Inventors: Kenji Ohgiyama, Kiyoaki Tsumura, Koji Yamashita, Toshio Takeuchi, Susumu Ishida, Kenji Kan
  • Publication number: 20030123499
    Abstract: A semiconductor laser element and a protective wall surrounding the element are provided on the surface of a metal frame of a semiconductor laser device. Circumferential portions are provided on an outer periphery of the metal frame for rotating the optical axis of light originating from a light-emitting point of the semiconductor laser element to a direction along the surface of the metal frame. By way of a guide of an optical pickup base corresponding to the circumferential portions, the semiconductor laser device is mounted on the optical pickup base.
    Type: Application
    Filed: June 28, 2002
    Publication date: July 3, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kenji Ohgiyama, Kiyoaki Tsumura, Koji Yamashita, Toshio Takeuchi, Susumu Ishida, Kenji Kan
  • Patent number: 6288376
    Abstract: According to a method of melting a bump improved to omit processes of flux application, reflow, cleaning and drying, a bump formed on a substrate is heated and melted by electromagnetic induction using an induction heating coil in ambient of low oxygen concentration.
    Type: Grant
    Filed: July 29, 1999
    Date of Patent: September 11, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kiyoaki Tsumura
  • Patent number: 5565378
    Abstract: A passive state film is formed on a surface of a bonding pad as follows: A silicon substrate 71 is immersed in solution continuously supplied with ozone. Since ozone is continuously supplied, it is possible to maintain the concentration of the dissolved ozone in the solution above a predetermined concentration. Therefore, it is possible to make the speed of formation of the passive state film higher than the speed of fusion of aluminum, which is a main constituent of the bonding pad. Accordingly, it is possible to form a passive state film with no pinholes.
    Type: Grant
    Filed: December 29, 1992
    Date of Patent: October 15, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigeru Harada, Kimio Hagi, Kiyoaki Tsumura
  • Patent number: 5334803
    Abstract: A semiconductor device of the present invention accommodates a large semiconductor chip in a downsized package without impairing its reliability. The semiconductor chip is bonded on a relatively small die pad. Common inner leads and a plurality of inner leads are disposed opposite and spaced from the semiconductor chip by a gap ranging from 0.1 mm to 0.4 mm and the gap between the semiconductor chip and the common inner leads and the plurality of inner leads is filled with a resin which forms part of a resin package.
    Type: Grant
    Filed: October 28, 1992
    Date of Patent: August 2, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Ken Yamamura, Naoto Ueda, Kazunari Michii, Hitoshi Fujimoto, Kiyoaki Tsumura, Hitoshi Sasaki, Takashi Miyamoto
  • Patent number: 5293066
    Abstract: Leads near a die pad of a lead frame for a semiconductor device include terminal leads in a pattern on an insulating resin layer. The inner ends of the terminal leads are connected with gold wires to electrode pads of a semiconductor chip, and the outer ends of the terminal leads are also connected with gold wires to inner lead portions of the leads. Wide ground pads are provided which extend from the inner lead portions to the die pad. Ground electrodes on the semiconductor chip are connected with wires to the ground pads to which the insulating resin layer is bonded.
    Type: Grant
    Filed: March 6, 1992
    Date of Patent: March 8, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kiyoaki Tsumura
  • Patent number: 5229646
    Abstract: A semiconductor device formed by a semiconductor chip bonded to a lead frame die pad. The bonding material, such as a silicone resin, has an elasticity modulus ranging from 1 Kg/cm.sup.2 to 100 Kg/cm.sup.2 from room temperature to 400.degree. C. The lead frame electrodes are connected to the semiconductor chip electrodes by copper alloy wires.
    Type: Grant
    Filed: March 17, 1992
    Date of Patent: July 20, 1993
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kiyoaki Tsumura
  • Patent number: 5124277
    Abstract: In an internal wire bonding section of a semiconductor device, electrodes pads (e.g., Al pads) which are not connected to leads are ball-bonded with metallic balls (e.g., Au balls) to improve moisture resistance and to thereby reduce the rate of corrosion of internal portions of the semiconductor device. The operation of the semiconductor device manufacturing apparatus for ball bonding conforms to the conventional wire bonding operation, so that the existing process can be used without significantly improving the apparatus or significantly changing the semiconductor manufacturing method.
    Type: Grant
    Filed: January 9, 1991
    Date of Patent: June 23, 1992
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kiyoaki Tsumura
  • Patent number: 5116783
    Abstract: A method of producing a semiconductor device includes bonding a semiconductor chip to a die pad of a lead frame by means of a silicone resin, to bonding a copper wire and an aluminum electrode of the semiconductor chip in such a manner that intermetallic compound mainly consisting of CuAl.sub.2 is formed in the bonding region. This method suppresses the deterioration of the copper-aluminum alloy layer and these semiconductor devices have a high reliability at a high temperature, as well as uniform quality in the production.
    Type: Grant
    Filed: August 11, 1989
    Date of Patent: May 26, 1992
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kiyoaki Tsumura
  • Patent number: 5093712
    Abstract: A semiconductor device sealed with resin is disclosed. This semiconductor device comprises a semiconductor element, a lead, and a wire electrically connecting said semiconductor element and said lead. The semiconductor element, the wire, and a portion of the lead are sealed with sealing resin. Calcium hydroxide is added into the sealing resin to serve as a corrosion inhibitor. In the semiconductor device sealed with resin, corrosion of the copper wire can thus be suppressed in high temperature environments.
    Type: Grant
    Filed: November 13, 1990
    Date of Patent: March 3, 1992
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoshihiro Matsunaga, Tadao Nishimori, Hiromasa Matsuoka, Kozo Shimamoto, Kiyoaki Tsumura
  • Patent number: 5023697
    Abstract: A semiconductor device in accordance with the present invention includes a semiconductor chip which is bonded to a die pad using a solder having a liquidus temperature of 370.degree. C. or less. A copper ball is moved to contact an Al electrode pad on the semiconductor chip in less than 150 ms after formation of the ball. Plastic deformation takes place so that the copper ball is pressed against the aluminum electrode pad and the height of the copper ball becomes 25 .mu.m or less. It is possible to firmly wire the Al pad on the semiconductor chip and the inner lead frame without cracking the glass coating by utilizing a silver plating on the die pad and an Au-metallized layer on the rear side of the semiconductor chip. It is also possible to decrease the work hardening property of the Cu ball and prevent Al exudation when the Cu ball is bonded to the Al electrode pad.
    Type: Grant
    Filed: April 6, 1990
    Date of Patent: June 11, 1991
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kiyoaki Tsumura
  • Patent number: 5003373
    Abstract: A structure of an electrode junction for a semiconductor device comprises an insulating film covering the entire surface of a silicon substrate, an aluminum electrode layer which is formed on the insulating film, a copper ball bonded on the electrode layer, and a copper-aluminum alloy layer continuously formed from the copper ball to the aluminum electrode layer. The aluminum layer under the copper ball is not separated from the aluminum layer surrounding the copper ball, so that alloy layer deterioration along the periphery thereof does not cause the electrical resistance to increase. This structure will increase the device life time to the maximum level.
    Type: Grant
    Filed: October 26, 1988
    Date of Patent: March 26, 1991
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kiyoaki Tsumura, Hitoshi Fujimoto
  • Patent number: 4984056
    Abstract: A semiconductor integrated circuit device includes a tetraethylorthosilicate film between a TiN film and a field oxide film disposed. This structure greatly reduced the possibility of separation of films in the bonding structure and contact failure as part of a wire bonding structure.
    Type: Grant
    Filed: December 14, 1989
    Date of Patent: January 8, 1991
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hitoshi Fujimoto, Kiyoaki Tsumura
  • Patent number: 4886200
    Abstract: A wire bonding capillary tip is disclosed. A metal ball at the end of a bonding wire is positioned adjacent a material to be bonded, and pressed against the material to plastically deform the ball. The orientation of the load applied to the ball changes continuously and smoothly. Ultrasonic vibrations are applied to the metal ball to diffuse elements of the metal ball and the material mutually. The capillary tip includes a flat loading surface to press the metal ball, a through-hole opened to the loading surface for passing the wire therethrough, and a convex surface around the opening of the through-hole which connects the through-hole to the flat loading surface continuously and smoothly.
    Type: Grant
    Filed: August 10, 1988
    Date of Patent: December 12, 1989
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kiyoaki Tsumura
  • Patent number: 4821944
    Abstract: The method for bonding a wire of this invention comprises the steps of: positioning a metal ball or a wire on a material (to be bonded); applying a pressing force on the metal ball or the wire against the material (to be bonded) and deforming it; inducing eddy currents in the wire to generate heat energy, whereby elements of the wire and the material (to be bonded) are mutually diffused by means of the heat energy and the pressing force, and bonding is completed. The wire bonding apparatus of this invention comprises: a capillary tip having a through-hole which opens onto a end thereof and through which a wire is passed, the capillary tip pressing the wire against a material to be bonded by the end of the tip (flat face); an electromagnetic coil provided around the end of the capillary tip to surround the through-hole; and a power source for supplying a high-frequency current to the electromagnetic coil.
    Type: Grant
    Filed: August 9, 1988
    Date of Patent: April 18, 1989
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kiyoaki Tsumura
  • Patent number: RE35496
    Abstract: A semiconductor device of the present invention accommodates a large semiconductor chip in a downsized package without impairing its reliability. The semiconductor chip is bonded on a relatively small die pad. Common inner leads and a plurality of inner leads are disposed opposite and spaced from the semiconductor chip by a gap ranging from 0.1 mm to 0.4 mm and the gap between the semiconductor chip and the common inner leads and the plurality of inner leads is filled with a resin which forms pan of a resin package.
    Type: Grant
    Filed: September 8, 1995
    Date of Patent: April 29, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Ken Yamamura, Naoto Ueda, Kazunari Michii, Hitoshi Fujimoto, Kiyoaki Tsumura, Hitoshi Sasaki, Takashi Miyamoto