Patents by Inventor Andrew A. Allerman

Andrew A. Allerman 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
  • Method of making AlInSb by metal-organic chemical vapor deposition
    Patent number: 6071109
    Abstract: A method for producing aluminum-indium-antimony materials by metal-organic chemical vapor deposition (MOCVD). This invention provides a method of producing Al.sub.X In.sub.1-x Sb crystalline materials by MOCVD wherein an Al source material, an In source material and an Sb source material are supplied as a gas to a heated substrate in a chamber, said Al source material, In source material, and Sb source material decomposing at least partially below 525.degree. C. to produce Al.sub.x In.sub.1-x Sb crystalline materials wherein x is greater than 0.002 and less than one.
    Type: Grant
    Filed: February 24, 1999
    Date of Patent: June 6, 2000
    Assignee: Sandia Corporation
    Inventors: Robert M. Biefeld, Andrew A. Allerman, Kevin C. Baucom
  • Infrared light sources with semimetal electron injection
    Patent number: 5995529
    Abstract: An infrared light source is disclosed that comprises a layered semiconductor active region having a semimetal region and at least one quantum-well layer. The semimetal region, formed at an interface between a GaAsSb or GalnSb layer and an InAsSb layer, provides electrons and holes to the quantum-well layer to generate infrared light at a predetermined wavelength in the range of 2-6 .mu.m. Embodiments of the invention can be formed as electrically-activated light-emitting diodes (LEDs) or lasers, and as optically-pumped lasers. Since the active region is unipolar, multiple active regions can be stacked to form a broadband or multiple-wavelength infrared light source.
    Type: Grant
    Filed: April 10, 1997
    Date of Patent: November 30, 1999
    Assignee: Sandia Corporation
    Inventors: Steven R. Kurtz, Robert M. Biefeld, Andrew A. Allerman