Patents by Inventor Tatsuo Tokue

Tatsuo Tokue 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).

  • Method of producing a semiconductor device
    Patent number: 6467666
    Abstract: A method of producing a semiconductor device of the present invention is applicable to a multilayer wafer for leadless chip carrier packages and breaks it on a package basis. The method begins with a step of forming a generally V-shaped groove in one major surfaces of the wafer in the direction of thickness of the wafer. A weak, cleaving portion is formed in the other major surface of the wafer in alignment with the groove. A cleaving force is exerted on the wafer to thereby form a break in the cleaving portion, so that the wafer is caused to break from the groove toward the cleaving portion in the direction of thickness of the wafer. The cleaving portion may be replaced with a strong, non-cleaving portion, in which case the break is formed in the interface between the non-cleaving portion and the wafer due to a difference in cleaving force.
    Type: Grant
    Filed: May 30, 2001
    Date of Patent: October 22, 2002
    Assignee: NEC Corporation
    Inventors: Seiji Ichikawa, Tatsuo Tokue, Nobuo Nagano, Fumie Ogihara, Taku Sato
  • Method of producing a semiconductor device
    Publication number: 20010048014
    Abstract: A method of producing a semiconductor device of the present invention is applicable to a multilayer wafer for leadless chip carrier packages and breaks it on a package basis. The method begins with a step of forming a generally V-shaped groove in one major surfaces of the wafer in the direction of thickness of the wafer. A weak, cleaving portion is formed in the other major surface of the wafer in alignment with the groove. A cleaving force is exerted on the wafer to thereby form a break in the cleaving portion, so that the wafer is caused to break from the groove toward the cleaving portion in the direction of thickness of the wafer. The cleaving portion may be replaced with a strong, non-cleaving portion, in which case the break is formed in the interface between the non-cleaving portion and the wafer due to a difference in cleaving force.
    Type: Application
    Filed: May 30, 2001
    Publication date: December 6, 2001
    Applicant: NEC Corporation
    Inventors: Seiji Ichikawa, Tatsuo Tokue, Nobuo Nagano, Fumie Ogihara, Taku Sato