Patents by Inventor Mitsuaki OKUBO

Mitsuaki OKUBO 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).

  • Copper pillar bump having annular protrusion
    Patent number: 11380642
    Abstract: A copper pillar bump for an electrode pad of a semiconductor chip includes a first copper layer, a first metal layer formed directly on the first copper layer, a second copper layer formed directly on the first metal layer, and a second metal layer formed directly on the second copper layer, wherein the first metal layer and the second metal layer are made of a metal having a different etching rate than copper, wherein an outer perimeter ring of the first metal layer protrudes beyond a lateral surface of the first copper layer, and wherein an outer perimeter ring of the second metal layer protrudes beyond a lateral surface of the second copper layer.
    Type: Grant
    Filed: November 5, 2020
    Date of Patent: July 5, 2022
    Assignee: SHINKO ELECTRIC INDUSTRIES CO., LTD.
    Inventors: Kengo Yamamoto, Daisuke Ito, Mitsuaki Okubo, Kenji Uchida
  • COPPER PILLAR BUMP HAVING ANNULAR PROTRUSION
    Publication number: 20210175193
    Abstract: A copper pillar bump for an electrode pad of a semiconductor chip includes a first copper layer, a first metal layer formed directly on the first copper layer, a second copper layer formed directly on the first metal layer, and a second metal layer formed directly on the second copper layer, wherein the first metal layer and the second metal layer are made of a metal having a different etching rate than copper, wherein an outer perimeter ring of the first metal layer protrudes beyond a lateral surface of the first copper layer, and wherein an outer perimeter ring of the second metal layer protrudes beyond a lateral surface of the second copper layer.
    Type: Application
    Filed: November 5, 2020
    Publication date: June 10, 2021
    Inventors: Kengo YAMAMOTO, Daisuke ITO, Mitsuaki OKUBO, Kenji UCHIDA