Patents by Inventor David H. Kinghorn

David H. Kinghorn 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).

  • Solderable intergrated circuit lead frames plated with tin and palladium
    Patent number: 5635755
    Abstract: A solderable lead frame is disclosed which includes a copper base lead frame containing a one layer or plated tin or tin alloy and another layer of plated palladium. The tin plating covers only external portions of the leads, whereas the palladium covers the external regions including the tin plating, and extends into internal portions of the lead frame. A diffusion barrier, of cobalt or nickel, is provided on the base lead frame beneath the tin plating.
    Type: Grant
    Filed: June 27, 1996
    Date of Patent: June 3, 1997
    Assignee: National Semiconductor Corporation
    Inventor: David H. Kinghorn
  • Process for preparing solderable integrated circuit lead frames by plating with tin and palladium
    Patent number: 5454929
    Abstract: A process for preparing a solderable lead frame from a copper base lead frame is disclosed using plating of tin or tin alloys followed by plating of palladium. Preferably, the tin plating is a spot plating to deposit tin only on the external leads and the palladium plating is a flood plating to deposit palladium over the entire lead frame. A diffusion barrier, preferably of cobalt or nickel, can be applied by plating the base lead frame before tin plating.
    Type: Grant
    Filed: June 16, 1994
    Date of Patent: October 3, 1995
    Assignee: National Semiconductor Corporation
    Inventor: David H. Kinghorn