Patents by Inventor Darwin J. Brown

Darwin J. Brown 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).

  • High gain photoconductive semiconductor switch having tailored doping profile zones
    Patent number: 6248992
    Abstract: A photoconductive semiconductor switch with tailored doping profile zones beneath and extending laterally from the electrical contacts to the device. The zones are of sufficient depth and lateral extent to isolate the contacts from damage caused by the high current filaments that are created in the device when it is turned on. The zones may be formed by etching depressions into the substrate, then conducting epitaxial regrowth in the depressions with material of the desired doping profile. They may be formed by surface epitaxy. They may also be formed by deep diffusion processes. The zones act to reduce the energy density at the contacts by suppressing collective impact ionization and formation of filaments near the contact and by reducing current intensity at the contact through enhanced current spreading within the zones.
    Type: Grant
    Filed: June 18, 1999
    Date of Patent: June 19, 2001
    Assignee: Sandia Corporation
    Inventors: Albert G. Baca, Guillermo M. Loubriel, Alan Mar, Fred J Zutavern, Harold P. Hjalmarson, Andrew A. Allerman, Thomas E. Zipperian, Martin W. O'Malley, Wesley D. Helgeson, Gary J. Denison, Darwin J. Brown, Charles T. Sullivan, Hong Q. Hou