Patents by Inventor John Franz Geisz

John Franz Geisz 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).

  • Tunnel junctions for multijunction solar cells
    Patent number: 11527667
    Abstract: Tunnel junctions for multijunction solar cells are provided. According to an aspect of the invention, a tunnel junction includes a first layer including p-type AlGaAs, a second layer including n-type GaAs, wherein the second layer is a quantum well, and a third layer including n-type AlGaAs or n-type lattice matched AlGaInP. The quantum well can be GaAs or AlxGaAs with x being more than about 40%, and lattice matched GaInAsNSb in the Eg range of from about 0.8 to about 1.4 eV.
    Type: Grant
    Filed: April 27, 2018
    Date of Patent: December 13, 2022
    Assignees: Alliance for Sustainable Energy, LLC, The Regents of the University of California, A California Corporation
    Inventors: Nikhil Jain, Myles Aaron Steiner, John Franz Geisz, Emmett Edward Perl, Ryan Matthew France
  • Multijunction solar cells with graded buffer Bragg reflectors
    Patent number: 11205734
    Abstract: Distributed Bragg reflectors are incorporated into the compositionally graded buffers of metamorphic solar cells, adding functionality to the buffer without adding cost. The reflection aids in collection in subcells that are optically thin due to low diffusion length, high bulk recombination, radiation hardness, partially-absorbing quantum structures, or simply for cost savings. Performance enhancements are demonstrated in GaAs subcells with QWs, which is beneficial when GaAs is not the ideal bandgap.
    Type: Grant
    Filed: February 22, 2019
    Date of Patent: December 21, 2021
    Assignees: Alliance for Sustainable Energy, LLC, California Institute of Technology
    Inventors: Ryan Matthew France, John Franz Geisz, Pilar Espinet-Gonzalez
  • MULTIJUNCTION SOLAR CELLS WITH GRADED BUFFER BRAGG REFLECTORS
    Publication number: 20190259897
    Abstract: Distributed Bragg reflectors are incorporated into the compositionally graded buffers of metamorphic solar cells, adding functionality to the buffer without adding cost. The reflection aids in collection in subcells that are optically thin due to low diffusion length, high bulk recombination, radiation hardness, partially-absorbing quantum structures, or simply for cost savings. Performance enhancements are demonstrated in GaAs subcells with QWs, which is beneficial when GaAs is not the ideal bandgap.
    Type: Application
    Filed: February 22, 2019
    Publication date: August 22, 2019
    Inventors: Ryan Matthew France, John Franz Geisz, Pilar Espinet-Gonzalez
  • TUNNEL JUNCTIONS FOR MULTIJUNCTION SOLAR CELLS
    Publication number: 20180315879
    Abstract: Tunnel junctions for multijunction solar cells are provided. According to an aspect of the invention, a tunnel junction includes a first layer including p-type AlGaAs, a second layer including n-type GaAs, wherein the second layer is a quantum well, and a third layer including n-type AlGaAs or n-type lattice matched AlGaInP. The quantum well can be GaAs or AlxGaAs with x being more than about 40%, and lattice matched GaInAsNSb in the Eg range of from about 0.8 to about 1.4 eV.
    Type: Application
    Filed: April 27, 2018
    Publication date: November 1, 2018
    Inventors: Nikhil Jain, Myles Aaron Steiner, John Franz Geisz, Emmett Edward Perl, Ryan Matthew France