Patents by Inventor Roger E. Welser

Roger E. Welser 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).

  • Biopolar transistor with lattice matched base layer
    Publication number: 20020121674
    Abstract: A semiconductor material which has a high carbon dopant concentration and is composed of gallium, indium, arsenic and nitrogen is disclosed. The material is useful in forming the base layer of gallium arsenide based heterojunction bipolar transistors because it can be lattice matched to gallium arsenide by controlling the concentration of indium and nitrogen. The disclosed semiconductor materials have a low sheet resistivity because of the high carbon dopant concentration obtained.
    Type: Application
    Filed: November 27, 2001
    Publication date: September 5, 2002
    Applicant: Kopin Corporation
    Inventors: Roger E. Welser, Paul M. Deluca, Noren Pan