Patents by Inventor Masaaki Sone

Masaaki Sone 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: 6617200
    Abstract: The present invention provides a semiconductor device that makes it possible to expose the back side of a die pad as well as a method for fabricating the same. The semiconductor device can include a lead frame that has portions to be sandwiched by first and second molds and a die pad that is down set at a distance greater than the depth of a recessed part of the first mold. The die pad is placed on the bottom of the recessed part of the first mold and the lead frame is disposed so that the portions to be sandwiched are suspended above the first mold. The molding process is carried out as the second mold presses the portions of the lead frame to be sandwiched in the direction of the first mold.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: September 9, 2003
    Assignee: Seiko Epson Corporation
    Inventor: Masaaki Sone
  • Patent number: 6608369
    Abstract: The invention provides a highly reliable lead frame, in spite of its structure, in which a bottom surface of a die pad thereof is exposed. The invention also provides a semiconductor device, a method for manufacturing the semiconductor device, a circuit board and electronic equipment. The semiconductor device includes a semiconductor chip, a die pad having an end section formed with a thin portion that is thinner than a central section thereof, and a sealing material. One surface of the thin portion of the die pad is coplanar with one surface of the central section. The sealing material leaves the surfaces of the thin portion and the central section that are coplanar exposed, and seals the end section of the die pad.
    Type: Grant
    Filed: May 18, 2001
    Date of Patent: August 19, 2003
    Assignee: Seiko Epson Corporation
    Inventor: Masaaki Sone
  • Publication number: 20020022304
    Abstract: To provide a semiconductor device that makes it possible to expose the back side of a die pad, a method for fabricating the same, a circuit board and electronic devices, a lead frame 10 has portions to be sandwiched by first and second molds 36 and 38 and a die pad 14 that is down set at a distance greater than the depth of a recessed part of the first mold 36. The die pad 14 is placed on the bottom of the recessed part of the first mold 36 and the lead frame 10 is disposed so that the portions to be sandwiched are suspended above the first mold 36. The molding process is carried out as the second mold 38 presses the portions of the lead frame 10 to be sandwiched in the direction of the first mold 36.
    Type: Application
    Filed: June 29, 2001
    Publication date: February 21, 2002
    Applicant: Seiko Epson Corporation
    Inventor: Masaaki Sone
  • Publication number: 20020017706
    Abstract: To provide a highly reliable lead frame in spite of its structure in which a bottom surface of a die pad thereof is exposed, a semiconductor device and a method for manufacturing the same, a circuit board and electronic equipment, the semiconductor device includes a semiconductor chip 30, a die pad 14 having an end section formed with a thin portion 16 thinner than a central section 18 thereof, and a sealing material 42, wherein one surface of the thin portion 16 of the die pad 14 is formed to be coplanar with one surface of the central section 18, and the sealing material 42 leaves exposed the surfaces of the thin portion 16 and the central section 18 in the coplanar surface of the die pad 14, and seals the end section of the die pad 14.
    Type: Application
    Filed: May 18, 2001
    Publication date: February 14, 2002
    Applicant: Seiko Epson Corporation
    Inventor: Masaaki Sone