Patents by Inventor Frank David Lachenmaier

Frank David Lachenmaier 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).

  • Durable substrate subassembly for transistor switch module
    Patent number: 5895974
    Abstract: A durable substrate subassembly for a high power transistor switching module. The substrate subassembly is durable because wire bonds to the semiconductor device electrodes are replaced with a soldered metal/ceramic composite conductor. The part of the composite conductor contacting the semiconductor device has a coefficient of thermal expansion close to that of the semiconductor device. The metal of the composite conductor is preferably a strip of copper foil. The ceramic portion is a layer of alumina on the copper foil that is generally coextensive with the semiconductor device electrodes.
    Type: Grant
    Filed: April 6, 1998
    Date of Patent: April 20, 1999
    Assignee: Delco Electronics Corp.
    Inventors: Charles Tyler Eytcheson, Todd G. Nakanishi, Frank David Lachenmaier, Michael D. Bramel