Patents by Inventor Koyuki KAWAKAMI

Koyuki KAWAKAMI 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).

  • Composite wiring substrate and semiconductor device
    Patent number: 11706877
    Abstract: A composite wiring substrate includes a first wiring substrate including a first connection terminal, a second wiring substrate including a second connection terminal facing the first connection terminal, and a joint material joining the first connection terminal and the second connection terminal. The first outline of the first connection terminal is inside the second outline of the second connection terminal in a plan view. The joint material includes a first portion formed of an intermetallic alloy of copper and tin, and contacting each of the first connection terminal and the second connection terminal, and a second portion formed of an alloy of tin and bismuth, and including a portion between the first outline and the second outline in the plan view. The second portion contains the bismuth at a higher concentration than in the eutectic composition of a tin-bismuth alloy, and is separated from the second connection terminal.
    Type: Grant
    Filed: May 2, 2022
    Date of Patent: July 18, 2023
    Assignee: SHINKO ELECTRIC INDUSTRIES CO., LTD.
    Inventors: Shota Miki, Koyuki Kawakami, Kiyoshi Oi, Kei Murayama, Mitsuhiro Aizawa
  • COMPOSITE WIRING SUBSTRATE AND SEMICONDUCTOR DEVICE
    Publication number: 20220361342
    Abstract: A composite wiring substrate includes a first wiring substrate including a first connection terminal, a second wiring substrate including a second connection terminal facing the first connection terminal, and a joint material joining the first connection terminal and the second connection terminal. The first outline of the first connection terminal is inside the second outline of the second connection terminal in a plan view. The joint material includes a first portion formed of an intermetallic alloy of copper and tin, and contacting each of the first connection terminal and the second connection terminal, and a second portion formed of an alloy of tin and bismuth, and including a portion between the first outline and the second outline in the plan view. The second portion contains the bismuth at a higher concentration than in the eutectic composition of a tin-bismuth alloy, and is separated from the second connection terminal.
    Type: Application
    Filed: May 2, 2022
    Publication date: November 10, 2022
    Inventors: Shota MIKI, Koyuki KAWAKAMI, Kiyoshi OI, Kei MURAYAMA, Mitsuhiro AIZAWA