Patents by Inventor Francis J. Kub

Francis J. Kub 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: 20240120201
    Abstract: A technique for selective-area diffusion doping of III-N epitaxial material layers and for fabricating power device structures utilizing this technique. Dopant species such as Mg are introduced into the III-N material layer and are diffused into the III-N material by annealing under stable or metastable conditions. The dopant species can be introduced via deposition of a metal or alloy layer containing such species using sputtering, e-beam evaporation or other technique known to those skilled in the art. The dopant material layer is capped with a thermally stable layer to prevent decomposition and out-diffusion, and then is annealed under stable or metastable conditions to diffuse the dopant into the III-N material GaN without decomposing the surface.
    Type: Application
    Filed: March 31, 2023
    Publication date: April 11, 2024
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Travis J. Anderson, Mona A. Ebrish, Alan G. Jacobs, Karl D. Hobart, Francis J. Kub
  • Publication number: 20240097064
    Abstract: A light controlled semiconductor switch (LCSS), method of making, and method of using are provided. In embodiments, a vertical LCSS includes: a semiconductor body including a photoactive layer of gallium nitride (GaN) doped with carbon; a first electrode in contact with a first surface of the semiconductor body, the first electrode defining an area through which light energy from at least one light source can impinge on the first surface; and a second electrode in contact with a second surface of the semiconductor body opposed to the first surface, wherein the vertical LCSS is configured to switch from a non-conductive off-state to a conductive on-state when the light energy impinging on the semiconductor body is sufficient to raise electrons within the photoactive layer into a conduction band of the photoactive layer.
    Type: Application
    Filed: September 8, 2023
    Publication date: March 21, 2024
    Inventors: Andrew D. Koehler, Travis J. Anderson, Geoffrey M. Foster, Karl D. Hobart, Francis J. Kub, Michael A. Mastro
  • Patent number: 11649159
    Abstract: A method of fabricating suspended beam silicon carbide microelectromechanical (MEMS) structure with low capacitance and good thermal expansion match. A suspended material structure is attached to an anchor material structure that is direct wafer bonded to a substrate. The anchor material structure and the suspended material structure are formed from either a hexagonal single-crystal SiC material, and the anchor material structure is bonded to the substrate while the suspended material structure does not have to be attached to the substrate. The substrate may be a semi-insulating or insulating SiC substrate. The substrate may have an etched recess region on the substrate first surface to facilitate the formation of the movable suspended material structures. The substrate may have patterned electrical electrodes on the substrate first surface, within recesses etched into the substrate.
    Type: Grant
    Filed: September 14, 2020
    Date of Patent: May 16, 2023
    Inventors: Francis J. Kub, Karl D. Hobart, Eugene A. Imhoff, Rachael L. Myers-Ward
  • Patent number: 11342420
    Abstract: Current conducting devices and methods for their formation are disclosed. Described are vertical current devices that include a substrate, an n-type material layer, a plurality of p-type gates, and a source. The n-type material layer disposed on the substrate and includes a current channel. A plurality of p-type gates are disposed on opposite sides of the current channel. A source is disposed on a distal side of the current channel with respect to the substrate. The n-type material layer comprises beta-gallium oxide.
    Type: Grant
    Filed: September 15, 2020
    Date of Patent: May 24, 2022
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Francis J. Kub, Travis J. Anderson, Marko J. Tadjer, Andrew D. Koehler, Karl D. Hobart
  • Patent number: 11227943
    Abstract: A high electron mobility transistor (HEMT) and method of producing the same are provided. The HEMT includes a barrier layer formed on a GaN layer. The HEMT also includes a ZrO2 gate dielectric layer formed by either a ZTB precursor, a TDMA-Zr precursor, or both. The HEMT may also include a recess in the barrier layer in the gate region of the HEMT. The HEMTs may operate in an enhancement mode.
    Type: Grant
    Filed: June 25, 2018
    Date of Patent: January 18, 2022
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Travis J. Anderson, Virginia D. Wheeler, Karl D. Hobart, Francis J. Kub
  • Patent number: 11171055
    Abstract: A method of cleaving includes providing a substrate. Optionally, the substrate includes ?-gallium oxide, hexagonal zinc sulfide, or magnesium selenide. The substrate includes at least one natural cleave plane and a crystallinity. The substrate is cleaved along a first natural cleave plane of the at least one natural cleave plane. The cleaving the substrate along the first natural cleave plane includes the following. A micro-crack is generated in the substrate while maintaining the crystallinity adjacent to the micro-crack by generating a plurality of phonons in the substrate, the micro-crack comprising a micro-crack direction along the first natural cleave plane. The micro-crack is propagated along the first natural cleave plane while maintaining the crystallinity adjacent to the micro-crack. Optionally, generating a micro-crack in the substrate by generating a plurality of phonons in the substrate includes generating the plurality of phonons by electron-hole recombination.
    Type: Grant
    Filed: January 30, 2020
    Date of Patent: November 9, 2021
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Nadeemullah A. Mahadik, Robert E. Stahlbush, Marko J. Tadjer, Karl D. Hobart, Francis J. Kub
  • Publication number: 20210005721
    Abstract: Current conducting devices and methods for their formation are disclosed. Described are vertical current devices that include a substrate, an n-type material layer, a plurality of p-type gates, and a source. The n-type material layer disposed on the substrate and includes a current channel. A plurality of p-type gates are disposed on opposite sides of the current channel. A source is disposed on a distal side of the current channel with respect to the substrate. The n-type material layer comprises beta-gallium oxide.
    Type: Application
    Filed: September 15, 2020
    Publication date: January 7, 2021
    Inventors: Francis J. Kub, Travis J. Anderson, Marko J. Tadjer, Andrew D. Koehler, Karl D. Hobart
  • Publication number: 20200407213
    Abstract: A method of fabricating suspended beam silicon carbide microelectromechanical (MEMS) structure with low capacitance and good thermal expansion match. A suspended material structure is attached to an anchor material structure that is direct wafer bonded to a substrate. The anchor material structure and the suspended material structure are formed from either a hexagonal single-crystal SiC material, and the anchor material structure is bonded to the substrate while the suspended material structure does not have to be attached to the substrate. The substrate may be a semi-insulating or insulating SiC substrate. The substrate may have an etched recess region on the substrate first surface to facilitate the formation of the movable suspended material structures. The substrate may have patterned electrical electrodes on the substrate first surface, within recesses etched into the substrate.
    Type: Application
    Filed: September 14, 2020
    Publication date: December 31, 2020
    Inventors: Francis J. Kub, Karl D. Hobart, Eugene A. Imhoff, Rachael L. Myers-Ward
  • Patent number: 10854457
    Abstract: An enhanced symmetric multicycle rapid thermal annealing process for removing defects and activating implanted dopant impurities in a III-nitride semiconductor sample. A sample is placed in an enclosure and heated to a temperature T1 under an applied pressure P1 for a time t1. While the heating of the sample is maintained, the sample is subjected to a series of rapid laser irradiations under an applied pressure P2 and a baseline temperature T2. Each of the laser irradiations heats the sample to a temperature Tmax above its thermodynamic stability limit. After a predetermined number of temperature pulses or a predetermined period of time, the laser irradiations are stopped and the sample is brought to a temperature T3 and held at T3 for a time t3 to complete the annealing.
    Type: Grant
    Filed: April 30, 2019
    Date of Patent: December 1, 2020
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Boris N. Feigelson, Francis J. Kub, Alan G. Jacobs
  • Patent number: 10777644
    Abstract: Current conducting devices and methods for their formation are disclosed. Described are vertical current devices that include a substrate, an n-type material layer, a plurality of p-type gates, and a source. The n-type material layer disposed on the substrate and includes a current channel. A plurality of p-type gates are disposed on opposite sides of the current channel. A source is disposed on a distal side of the current channel with respect to the substrate. The n-type material layer comprises beta-gallium oxide.
    Type: Grant
    Filed: April 27, 2018
    Date of Patent: September 15, 2020
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Francis J. Kub, Travis J. Anderson, Marko J. Tadjer, Andrew D. Koehler, Karl D. Hobart
  • Publication number: 20200251389
    Abstract: A method of cleaving includes providing a substrate. Optionally, the substrate includes ?-gallium oxide, hexagonal zinc sulfide, or magnesium selenide. The substrate includes at least one natural cleave plane and a crystallinity. The substrate is cleaved along a first natural cleave plane of the at least one natural cleave plane. The cleaving the substrate along the first natural cleave plane includes the following. A micro-crack is generated in the substrate while maintaining the crystallinity adjacent to the micro-crack by generating a plurality of phonons in the substrate, the micro-crack comprising a micro-crack direction along the first natural cleave plane. The micro-crack is propagated along the first natural cleave plane while maintaining the crystallinity adjacent to the micro-crack. Optionally, generating a micro-crack in the substrate by generating a plurality of phonons in the substrate includes generating the plurality of phonons by electron-hole recombination.
    Type: Application
    Filed: January 30, 2020
    Publication date: August 6, 2020
    Inventors: NADEEMULLAH A. MAHADIK, Robert E. Stahlbush, Marko J. Tadjer, Karl D. Hobart, Francis J. Kub
  • Patent number: 10717642
    Abstract: Electromechanical device structures are provided, as well as methods for forming them. The device structures incorporate at least a first and second substrate separated by an interface material layer, where the first substrate comprises an anchor material structure and at least one suspended material structure, optionally a spring material structure, and optionally an electrostatic sense electrode. The device structures may be formed by methods that include providing an interface material layer on one or both of the first and second substrates, bonding the interface materials to the opposing first or second substrate or to the other interface material layer, followed by forming the suspended material structure by etching.
    Type: Grant
    Filed: December 13, 2019
    Date of Patent: July 21, 2020
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Francis J. Kub, Karl D. Hobart, Eugene A. Imhoff, Rachael L. Myers-Ward, Eugene Cook, Jonathan Bernstein, Marc Weinberg
  • Publication number: 20200115219
    Abstract: Electromechanical device structures are provided, as well as methods for forming them. The device structures incorporate at least a first and second substrate separated by an interface material layer, where the first substrate comprises an anchor material structure and at least one suspended material structure, optionally a spring material structure, and optionally an electrostatic sense electrode. The device structures may be formed by methods that include providing an interface material layer on one or both of the first and second substrates, bonding the interface materials to the opposing first or second substrate or to the other interface material layer, followed by forming the suspended material structure by etching.
    Type: Application
    Filed: December 13, 2019
    Publication date: April 16, 2020
    Applicants: The Government of the United States of America, as represented by the Secretary of the Navy, The Charles Stark Draper Company
    Inventors: Francis J. Kub, Karl D. Hobart, Eugene A. Imhoff, Rachael L. Myers-Ward, Eugene Cook, Jonathan Bernstein, Marc Weinberg
  • Patent number: 10589983
    Abstract: Electromechanical device structures are provided, as well as methods for forming them. The device structures incorporate at least a first and second substrate separated by an interface material layer, where the first substrate comprises an anchor material structure and at least one suspended material structure, optionally a spring material structure, and optionally an electrostatic sense electrode. The device structures may be formed by methods that include providing an interface material layer on one or both of the first and second substrates, bonding the interface materials to the opposing first or second substrate or to the other interface material layer, followed by forming the suspended material structure by etching.
    Type: Grant
    Filed: September 7, 2017
    Date of Patent: March 17, 2020
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Francis J. Kub, Karl D. Hobart, Eugene A. Imhoff, Rachael L. Myers-Ward, Eugene Cook, Jonathan Bernstein, Marc Weinberg
  • Patent number: 10513462
    Abstract: A method for making transparent nanocomposite ceramics and other solid bulk materials from nanoparticle powders and transparent nanocomposite ceramics and other solid bulk materials formed using that method. A nanoparticle powder is placed into a reaction chamber and is treated to produce a clean surface powder. The clean surface powder is coated with a second material by means of p-ALD to produce core/shell or core multi shell nanoparticles having a coating or coatings of a other material surrounding the nanoparticle. The core/shell nanoparticles are cleaned and formed into green compact which is sintered to produce a transparent nanocomposite ceramic or other solid bulk material consisting of nanoparticles or core/shell nanoparticles uniformly embedded in a matrix of a different material, particularly in a matrix of a different ceramic material, formed by outer shell of initial core/shell. All steps are performed without exposing the material to the ambient.
    Type: Grant
    Filed: September 9, 2016
    Date of Patent: December 24, 2019
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Boris N. Feigelson, James A. Wollmershauser, Kedar Manandhar, Francis J. Kub
  • Patent number: 10494738
    Abstract: A method of growing crystalline materials on two-dimensional inert materials comprising functionalizing a surface of a two-dimensional inert material, growing a nucleation layer on the functionalized surface, and growing a crystalline material. A crystalline material grown on a two-dimensional inert material made from the process comprising functionalizing a surface of a two-dimensional inert material, growing a nucleation layer on the functionalized surface, and growing a crystalline material.
    Type: Grant
    Filed: January 28, 2019
    Date of Patent: December 3, 2019
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Neeraj Nepal, Virginia Wheeler, Charles R. Eddy, Jr., Francis J. Kub, Travis J. Anderson, Michael A. Mastro, Rachael L. Myers-Ward, Sandra C. Hangarter
  • Publication number: 20190341261
    Abstract: An enhanced symmetric multicycle rapid thermal annealing process for removing defects and activating implanted dopant impurities in a III-nitride semiconductor sample. A sample is placed in an enclosure and heated to a temperature T1 under an applied pressure P1 for a time t1. While the heating of the sample is maintained, the sample is subjected to a series of rapid laser irradiations under an applied pressure P2 and a baseline temperature T2. Each of the laser irradiations heats the sample to a temperature Tmax above its thermodynamic stability limit. After a predetermined number of temperature pulses or a predetermined period of time, the laser irradiations are stopped and the sample is brought to a temperature T3 and held at T3 for a time t3 to complete the annealing.
    Type: Application
    Filed: April 30, 2019
    Publication date: November 7, 2019
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Boris N. Feigelson, Francis J. Kub, Alan G. Jacobs
  • Publication number: 20190305157
    Abstract: An extreme ultraviolet (EUV) photodetector is formed by providing a substrate having a first doping type of material; forming a photodetector body layer having the first doping type of material over the substrate, wherein the photodetector body layer includes a carrier collection region and a potential barrier maximum level; and forming a carrier collection material layer over the photodetector body layer. The carrier collection region includes a region between the potential barrier maximum level and the carrier collection material layer. The potential barrier maximum level includes a height within the photodetector body layer that prevents photogenerated carriers created at a depth deeper than the potential barrier maximum level from transporting to the carrier collection region and the carrier collection material layer.
    Type: Application
    Filed: April 2, 2018
    Publication date: October 3, 2019
    Inventors: Francis J. Kub, Travis J. Anderson, Karl D. Hobart, Andrew D. Koehler
  • Patent number: 10424643
    Abstract: A device structure and method for improving thermal management in highly scaled, high power electronic and optoelectronic devices such as GaN FET and AlGaN/GaN HEMT devices by implementing diamond air bridges into such devices to remove waste heat. The diamond air bridge can be formed from a polycrystalline diamond material layer which can be grown on the surface of a dielectric material layer, on the surface of a III-nitride material, or on the surface of a diamond polycrystalline nucleation layer, and may be optimized to have a high thermal conductivity at the growth interface with the underlying material.
    Type: Grant
    Filed: April 23, 2019
    Date of Patent: September 24, 2019
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Karl D. Hobart, Andrew D. Koehler, Francis J. Kub, Travis J. Anderson, Tatyana I. Feygelson, Marko J. Tadjer, Lunet E. Luna
  • Publication number: 20190252501
    Abstract: A device structure and method for improving thermal management in highly scaled, high power electronic and optoelectronic devices such as GaN FET and AlGaN/GaN HEMT devices by implementing diamond air bridges into such devices to remove waste heat. The diamond air bridge can be formed from a polycrystalline diamond material layer which can be grown on the surface of a dielectric material layer, on the surface of a III-nitride material, or on the surface of a diamond polycrystalline nucleation layer, and may be optimized to have a high thermal conductivity at the growth interface with the underlying material.
    Type: Application
    Filed: April 23, 2019
    Publication date: August 15, 2019
    Inventors: Karl D. Hobart, Andrew D. Koehler, Francis J. Kub, Travis J. Anderson, Tatyana I. Feygelson, Marko J. Tadjer, Lunet E. Luna