Patents by Inventor Kazunao Tokunaga

Kazunao Tokunaga 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: 6077757
    Abstract: A method of fabricating a chip semiconductor device includes steps in which electrically conductive bumps are provided on electrodes of semiconductor elements on a wafer, an insulating substrate having an electrode pattern is combined onto the wafer so that the electrode pattern is made into contact with the bumps, only the wafer on which the semiconductor elements are provided is divided by grooves into a plurality of chips each of which has a semiconductor element, a liquid resin is flowed into the grooves and onto the chips for subsequent curing the resin, and the cured resin and the insulating substrate are concurrently cut along the grooves so that a plurality of semiconductor devices are formed.
    Type: Grant
    Filed: February 9, 1998
    Date of Patent: June 20, 2000
    Assignee: NEC Corporation
    Inventors: Hideki Mizuno, Kazunao Tokunaga
  • Patent number: 5786261
    Abstract: First, a non-doped AlGaAs layer and an n-GaAs layer serving as a conductive layer are formed in order on the surface of a semi-insulating GaAs substrate. Then, a photoresist film having an opening in its predetermined position is formed on the surface of the n-GaAs layer. Then, an electron beam is applied from the upside of the photoresist film by using the photoresist film as a mask. Thereby, a melted layer made of uniform AlGaAs is formed in a region of the n-GaAs layer, non-doped AlGaAs layer and upper portion of the GaAs substrate, which is under the opening 24a. Thereafter, the melted layer is recrystallized. In this case, the melted layer is formed into an amorphous or polycrystalline layer on the GaAs substrate and an device isolation layer is formed.
    Type: Grant
    Filed: February 4, 1997
    Date of Patent: July 28, 1998
    Assignee: NEC Corporation
    Inventor: Kazunao Tokunaga