Patents by Inventor Toshio Yokokawa

Toshio Yokokawa 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: 4704199
    Abstract: In a method of forming an iron oxide film of either Fe.sub.3 O.sub.4 or .alpha.-Fe.sub.2 O.sub.3 on a substrate with reactive sputtering of a target of iron, intensity of an emission spectrum of iron is previously determined as a predetermined value in connection with a desired one of Fe.sub.3 O.sub.4 and .alpha.-Fe.sub.2 O.sub.3 films. A light beam emitted from the glow discharge is measured to produce an electric signal representative of intensity of a measured spectrum of iron. Control operation is carried out to adjust the measured spectrum to the predetermined value. The electric signal may control either a flow rate of introducing oxygen gas into the space or intensity of an electric field produced between the substrate and the target.
    Type: Grant
    Filed: February 2, 1987
    Date of Patent: November 3, 1987
    Assignee: Anelva Corporation
    Inventors: Toshio Yokokawa, Yohichi Hirukawa