Patents by Inventor Jeffrey Y. Tsao

Jeffrey Y. Tsao 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).

  • Publication number: 20160087406
    Abstract: A laser-based white light illuminant comprises a III-nitride quantum dot laser diode and phosphors that convert the emitted laser light into white light. The laser light is emitted from an active region comprised of small quantum dots having a narrow size distribution, thereby providing narrower linewidths, decreased operating current density and increased peak efficiency. The white light illuminant has a number of advantages of LED-based solid state lighting, including higher power conversion efficiency, higher achievable luminous efficacy, and new and improved functionality.
    Type: Application
    Filed: December 1, 2015
    Publication date: March 24, 2016
    Inventors: Jonathan Wierer, JR., Jeffrey Y. Tsao, Arthur J. Fischer
  • Patent number: 9276382
    Abstract: Quantum-size-controlled photoelectrochemical (QSC-PEC) etching provides a new route to the precision fabrication of epitaxial semiconductor nanostructures in the sub-10-nm size regime. For example, quantum dots (QDs) can be QSC-PEC-etched from epitaxial InGaN thin films using narrowband laser photoexcitation, and the QD sizes (and hence bandgaps and photoluminescence wavelengths) are determined by the photoexcitation wavelength.
    Type: Grant
    Filed: February 17, 2015
    Date of Patent: March 1, 2016
    Assignee: Sandia Corporation
    Inventors: Arthur J. Fischer, Jeffrey Y. Tsao, Jonathan J. Wierer, Jr., Xiaoyin Xiao, George T. Wang
  • Publication number: 20150270136
    Abstract: Quantum-size-controlled photoelectrochemical (QSC-PEC) etching provides a new route to the precision fabrication of epitaxial semiconductor nanostructures in the sub-10-nm size regime. For example, quantum dots (QDs) can be QSC-PEC-etched from epitaxial InGaN thin films using narrowband laser photoexcitation, and the QD sizes (and hence bandgaps and photoluminescence wavelengths) are determined by the photoexcitation wavelength.
    Type: Application
    Filed: February 17, 2015
    Publication date: September 24, 2015
    Inventors: Arthur J. Fischer, Jeffrey Y. Tsao, Jonathan J. Wierer, JR., Xiaoyin Xiao, George T. Wang
  • Patent number: 7435297
    Abstract: A method for growing Group III nitride materials using a molten halide salt as a solvent to solubilize the Group-III ions and nitride ions that react to form the Group III nitride material. The concentration of at least one of the nitride ion or Group III cation is determined by electrochemical generation of the ions.
    Type: Grant
    Filed: April 8, 2005
    Date of Patent: October 14, 2008
    Assignee: Sandia Corporation
    Inventors: Karen E. Waldrip, Jeffrey Y. Tsao, Thomas M. Kerley
  • Patent number: 5389797
    Abstract: A photodetector that is responsive to a wavelength or wavelengths of interest which have heretofore been unrealized. The photodetector includes a resonant cavity structure bounded by first and second reflectors, the resonant cavity structure being resonant at the wavelength or wavelengths of interest for containing a plurality of standing waves therein. The photodetector further includes a radiation absorbing region disposed within the resonant cavity structure, the radiation absorbing region including a plurality of radiation absorbing layers spaced apart from one another by a distance substantially equal to a distance between antinodes of adjacent ones of the standing waves. Each of radiation absorbing layers is spatially positioned at a location of one of the antinodes of one of the standing waves such that radiation absorption is enhanced. The radiation absorbing layers may be either bulk layers or quantum wells includes a plurality of layers, each of which is comprised of a strained layer of InGaAs.
    Type: Grant
    Filed: February 24, 1993
    Date of Patent: February 14, 1995
    Assignee: The United States of America as represented by the Secretary of the Department of Energy
    Inventors: Robert P. Bryan, Gregory R. Olbright, Thomas M. Brennan, Jeffrey Y. Tsao
  • Patent number: 5171399
    Abstract: A method for on-line accurate monitoring and precise control of molecular beam epitaxial growth of Groups III-III-V or Groups III-V-V layers in an advanced semiconductor device incorporates reflection mass spectrometry. The reflection mass spectrometry is responsive to intentional perturbations in molecular fluxes incident on a substrate by accurately measuring the molecular fluxes reflected from the substrate.The reflected flux is extremely sensitive to the state of the growing surface and the measurements obtained enable control of newly forming surfaces that are dynamically changing as a result of growth.
    Type: Grant
    Filed: August 15, 1990
    Date of Patent: December 15, 1992
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Thomas M. Brennan, B. Eugene Hammons, Jeffrey Y. Tsao
  • Patent number: 4672254
    Abstract: A phase and amplitude compensated surface acoustic wave (SAW) structure is described in which computer controlled compensation is achieved by laser chemical etching of selective portions of a compound chemical film deposited on the surface of a piezoelectric SAW substrate in the path of propagation. The compound film comprises a layer of amplitude attenuating cermet material formed on the substrate and a phase compensating layer of molybdenum formed over the cermet material and in contact with the substrate surface.
    Type: Grant
    Filed: October 11, 1985
    Date of Patent: June 9, 1987
    Assignee: Massachusetts Institute of Technology
    Inventors: Victor S. Dolat, Daniel J. Ehrlich, Jeffrey Y. Tsao
  • Patent number: 4619894
    Abstract: A negative resist and masking process for microfabrication comprising an evaporated film of aluminum and oxygen which, in the as-deposited state, is highly conductive and has low resistance to etching, but when exposed to active radiation, such as by pulse laser thermal excitation, converts to a low electrical conductivity, high etchant resistive phase.
    Type: Grant
    Filed: April 12, 1985
    Date of Patent: October 28, 1986
    Assignee: Massachusetts Institute of Technology
    Inventors: Carl O. Bozler, Daniel J. Ehrlich, Jeffrey Y. Tsao