Patents by Inventor Atsutomo Tohi

Atsutomo Tohi 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 making isolated semiconductor devices utilizing ion-implantation of aluminum and heat treating
    Patent number: 4295898
    Abstract: In forming p.sup.+ -type isolation region to define an isolated n-type island region in an n-type epitaxial layer grown on a p-type semiconductor substrate, the p.sup.+ -type isolation region is formed by burying, prior to the growing of the epitaxial layer, an Al-ion-implanted region in the p-type substrate by means of ion implantation and subsequent heat-treatment for driving-in, thereby enabling a very quick forming of the isolation region and an accurate control of the resistivity of the epitaxial layer.
    Type: Grant
    Filed: May 8, 1980
    Date of Patent: October 20, 1981
    Assignee: Matsushita Electronics Corporation
    Inventors: Masakatsu Yoshida, Yoshihiko Tochio, Atsutomo Tohi