Patents by Inventor Valerl F. Tsvetkov

Valerl F. Tsvetkov 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).

  • One hundred millimeter high purity semi-insulating single crystal silicon carbide wafer
    Patent number: 7601441
    Abstract: A single polytype single crystal silicon carbide wafer is disclosed having a diameter greater than three inches and less than five inches, resistivity greater than 10,000 ohm-cm, a micropipe density less than 200 cm?2, and a combined concentration of shallow level dopants less than 5E16 cm?3.
    Type: Grant
    Filed: June 25, 2004
    Date of Patent: October 13, 2009
    Assignee: Cree, Inc.
    Inventors: Jason Ronald Jenny, David Phillip Malta, Hudson McDonald Hobgood, Stephan Georg Mueller, Mark Brady, Robert Tyler Leonard, Adrian Powell, Valerl F. Tsvetkov