Patents by Inventor Lawrence E. Tawyea

Lawrence E. Tawyea 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: 5536908
    Abstract: A printed circuit is provided that is capable of operating at temperatures above 200.degree. C. A printed wiring board has a plating scheme of Tin plating over sulfamate nickel plated over copper. The materials are electroplated in the pattern of the desired circuit. The copper provides a conductive material for carrying electrical current. The sulfamate nickel is a ductile material that serves as a barrier between the copper and the Tin and is able to maintain its strength under temperatures of above 200.degree. C. The Tin is compatible with the new solder compound that is used to solder electrical components to the board. The solder compound is comprised of Tin and Silver. This solder has a higher initial melting point than traditional Tin/Lead solders but has a lower solder reflow temperature than conventional HMP solder compounds. This new solder is also stronger than conventional HMP solder and contains virtually no Lead component.
    Type: Grant
    Filed: September 27, 1995
    Date of Patent: July 16, 1996
    Assignee: Schlumberger Technology Corporation
    Inventors: Richard K. Etchells, Lawrence E. Tawyea