Patents by Inventor Nibir K. Dhar

Nibir K. Dhar 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).

  • Molecular beam epitaxy growth of ternary and quaternary metal chalcogenide films
    Patent number: 7518207
    Abstract: The ternary alloy CdSexTe1-x(2 1 1) and the quaternary alloy Cd1-zZnzSexTe1-x have been grown on Si(2 1 1) substrates using molecular beam epitaxy (MBE). The growth of CdSeTe is facilitated using a compound CdTe effusion source and a Se effusion source while the growth of CdZnSeTe is facilitated using a compound CdTe effusion source, a compound ZnTe effusion source, and an elemental Se source. The alloy compositions (x) and (z) of CdSexTe1-x ternary compound and Cd1-zZnzSexTe1-x are controlled through the Se/CdTe and ZnTe/CdTe flux ratios. The rate of Se incorporation is higher than the rate of Te incorporation as growth temperature increases. As-grown CdSeTe with 4% Se and CdZnSeTe with 4% Zn+Se, which is substantially lattice matched to long-wavelength infrared HgCdTe materials, exhibits excellent surface morphology, low surface defect density (less than 500 cm2), and a narrow X-ray rocking curve (a full-width at half maximum of 103 arcsec).
    Type: Grant
    Filed: March 19, 2004
    Date of Patent: April 14, 2009
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Yuanping Chen, Gregory Brill, Nibir K. Dhar