Patents by Inventor Vladimir L. Tassev

Vladimir L. Tassev 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).

  • Patent number: 9777402
    Abstract: A method of forming a layered OP material is provided, where the layered OP material comprises an OPGaAs template, and a layer of GaP on the OPGaAs template. The OPGaAs template comprises a patterned layer of GaAs having alternating features of inverted crystallographic polarity of GaAs. The patterned layer of GaAs comprises a first feature comprising a first crystallographic polarity form of GaAs having a first dimension, and a second feature comprising a second crystallographic polarity form of GaAs having a second dimension. The layer of GaP on the patterned layer of GaAs comprises alternating regions of inverted crystallographic polarity that generally correspond to their underlying first and second features of the patterned layer of GaAs. Additionally, each of the alternating regions of inverted crystallographic polarity of GaP are present at about 100 micron thickness or more.
    Type: Grant
    Filed: March 10, 2017
    Date of Patent: October 3, 2017
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Vladimir L. Tassev, Rita D. Peterson
  • Publication number: 20170183793
    Abstract: A method of forming a layered OP material is provided, where the layered OP material comprises an OPGaAs template, and a layer of GaP on the OPGaAs template. The OPGaAs template comprises a patterned layer of GaAs having alternating features of inverted crystallographic polarity of GaAs. The patterned layer of GaAs comprises a first feature comprising a first crystallographic polarity form of GaAs having a first dimension, and a second feature comprising a second crystallographic polarity form of GaAs having a second dimension. The layer of GaP on the patterned layer of GaAs comprises alternating regions of inverted crystallographic polarity that generally correspond to their underlying first and second features of the patterned layer of GaAs. Additionally, each of the alternating regions of inverted crystallographic polarity of GaP are present at about 100 micron thickness or more.
    Type: Application
    Filed: March 10, 2017
    Publication date: June 29, 2017
    Inventors: Vladimir L. Tassev, Rita D. Peterson
  • Patent number: 9647156
    Abstract: A layered OP material is provided that comprises an OPGaAs template, and a layer of GaP on the OPGaAs template. The OPGaAs template comprises a patterned layer of GaAs having alternating features of inverted crystallographic polarity of GaAs. The patterned layer of GaAs comprises a first feature comprising a first crystallographic polarity form of GaAs having a first dimension, and a second feature comprising a second crystallographic polarity form of GaAs having a second dimension. The layer of GaP on the patterned layer of GaAs comprises alternating regions of inverted crystallographic polarity that generally correspond to their underlying first and second features of the patterned layer of GaAs. Additionally, each of the alternating regions of inverted crystallographic polarity of GaP are present at about 100 micron thickness or more. A method of forming the OPGaP is also provided.
    Type: Grant
    Filed: November 6, 2015
    Date of Patent: May 9, 2017
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Vladimir L. Tassev, Rita D. Peterson
  • Patent number: 7524375
    Abstract: The invention provides for growing semiconductor and other crystals by loading a vessel in its lower portion with a seed crystal, loading a charge thereon in the vessel, heating the charge to a molten state and electromagnetically stirring the melt using magnetic and electric fields to obtain a more uniform composition of melt and slowly reducing the temperature of the melt over the crystal to grow a more uniform crystal from such stirred melt.
    Type: Grant
    Filed: April 1, 2004
    Date of Patent: April 28, 2009
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Gerald W. Iseler, David F. Bliss, Vladimir L. Tassev
  • Patent number: 7276121
    Abstract: Method and apparatus are provided for forming metal nitride (MN), wherein M is contacted with iodine vapor or hydrogen iodide (HI) vapor to form metal iodide (MI) and then contacting MI with ammonia to form the MN in a process of reduced or no toxicity. Such method is conducted in a reactor that is maintained at a pressure below one atmosphere for enhanced uniformity of gas flow and of MN product. The MN is then deposited on a substrate, on one or more seeds or it can self-nucleate on the walls of a growth chamber, to form high purity and uniform metal nitride material. The inventive MN material finds use in semiconductor materials, in nitride electronic devices, various color emitters, high power microwave sources and numerous other electronic applications.
    Type: Grant
    Filed: November 10, 2004
    Date of Patent: October 2, 2007
    Assignee: United States of America as represented by the Secretary of the Air Force
    Inventors: David F. Bliss, Vladimir L. Tassev, Michael J. Suscavage, John S. Bailey
  • Patent number: 6969426
    Abstract: Method and apparatus are provided for forming metal nitride (MN), wherein M is contacted with iodine vapor or hydrogen iodide (HI) vapor to form metal iodide (MI) and then contacting MI with ammonia to form the MN in a process of reduced or no toxicity. Such method is conducted in a reactor that is maintained at a pressure below one atmosphere for enhanced uniformity of gas flow and of MN product. The MN is then deposited on a substrate, on one or more seeds or it can self-nucleate on the walls of a growth chamber, to form high purity and uniform metal nitride material. The inventive MN material finds use in semiconductor materials, in nitride electronic devices, various color emitters, high power microwave sources and numerous other electronic applications.
    Type: Grant
    Filed: February 26, 2002
    Date of Patent: November 29, 2005
    Inventors: David F. Bliss, Vladimir L. Tassev, Michael J. Suscavage, John S. Bailey
  • Patent number: 6849121
    Abstract: The invention provides for growing semiconductor and other crystals by loading a vessel in its lower portion with a seed crystal, loading a charge thereon in the vessel, heating the charge to a molten state and electromagnetically stirring the melt using magnetic and electric fields to obtain a more uniform composition of melt and slowly reducing the temperature of the melt over the crystal to grow a more uniform crystal from such stirred melt.
    Type: Grant
    Filed: April 23, 2002
    Date of Patent: February 1, 2005
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Gerald W. Iseler, David F. Bliss, Vladimir L. Tassev