Patents by Inventor Friedrich Brunner

Friedrich Brunner 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).

  • Etchant for polyimides
    Patent number: 4039371
    Abstract: A composition for etching polyimide based polymers comprised of a tetraalkyl ammonium hydroxide and an organic acid selected from the group of acetic acid, tartaric acid and oxalic acid.The etchant may be used to texture polyimide films or form perforations through polyimide substrates or layers, particularly in the fabrication of printed circuits and semiconductor devices where via holes are required for interconnection of circuitry.
    Type: Grant
    Filed: August 30, 1976
    Date of Patent: August 2, 1977
    Assignee: International Business Machines Corporation
    Inventors: Friedrich Brunner, Peter Frasch, Friedrich Schwerdt