Patents by Inventor Karl D. Hobart

Karl D. Hobart 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: 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
  • Publication number: 20200400578
    Abstract: A method for mapping and analyzing a GaN substrate to identify areas of the substrate suitable for fabrication of electronic devices thereon. Raman spectroscopy is performed over the surface of a GaN substrate to produce maps of the E2 and A1 peaks at a plurality of areas on the substrate surface, the E2 and A1 peaks being associated with known concentrations of defects and charge carriers, so that areas of the GaN substrate having relatively high resistivity or conductivity which make those areas suitable or unsuitable for fabrication of electronic devices can be identified. The devices can then be fabricated only on suitable areas of the substrate, or the size of the devices can be tailored to maximize the yield of devices fabricated thereon. Substrates not meeting a threshold level of defect and/or charge carrier concentration can be discarded without fabrication of poor-quality devices thereon.
    Type: Application
    Filed: June 19, 2020
    Publication date: December 24, 2020
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Travis J. Anderson, Jennifer K. Hite, James C. Gallagher, Karl D. Hobart
  • 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
  • Publication number: 20190360117
    Abstract: A method for growing polycrystalline diamond films having engineered grain growth and microstructure. Grain growth of a polycrystalline diamond film on a substrate is manipulated by growing the diamond on a nanopatterned substrate having features on the order of the initial grain size of the diamond film. By growing the diamond on such nanopatterned substrates, the crystal texture of a polycrystalline diamond film can be engineered to favor the preferred <110> orientation texture, which in turn enhances the thermal conductivity of the diamond film.
    Type: Application
    Filed: May 23, 2019
    Publication date: November 28, 2019
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Karl D. Hobart, Tatyana I. Feygelson, Marko J. Tadjer, Travis J. Anderson, Andrew D. Koehler, Sam Graham, JR., Mark Goorsky, Zhe Cheng, Luke Yates, Tingyu Bai, Yekan Wang
  • 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
  • Patent number: 10343900
    Abstract: Material structures and methods for etching hexagonal, single-crystal silicon carbide (SiC) materials are provided, which include selection of on-axis or near on-axis hexagonal single-crystal SiC material as the material to be etched. The methods include etching of SiC bulk substrate material, etching of SiC material layers bonded to a silicon oxide layer, etching of suspended SiC material layers, and etching of a SiC material layer anodically bonded to a glass layer. Plasma-etched hexagonal single-crystal SiC materials of the invention may be used to form structures that include, but are not limited to, microelectromechanical beams, microelectromechanical membranes, microelectromechanical cantilevers, microelectromechanical bridges, and microelectromechanical field effect transistor devices.
    Type: Grant
    Filed: September 7, 2017
    Date of Patent: July 9, 2019
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Eugene A. Imhoff, Francis J. Kub, Karl D. Hobart, Rachael L. Myers-Ward
  • Patent number: 10317210
    Abstract: According to one aspect, embodiments herein provide a gyroscope comprising an axially symmetric structure, and a plurality of transducers, each configured to perform at least one of driving and sensing motion of the axially symmetric structure, wherein the plurality of transducers is configured to drive the axially symmetric structure in at least a first vibratory mode and a second vibratory mode, and wherein the gyroscope is implemented on a hexagonal crystal-based substrate.
    Type: Grant
    Filed: May 20, 2016
    Date of Patent: June 11, 2019
    Assignees: THE CHARLES STARK DRAPER LABORATORY, INC., The United States of America, as represented by the Secretary of the Navy
    Inventors: Francis J. Kub, Karl D. Hobart, Eugene Imhoff, Rachael Myers-Ward, Eugene H. Cook, Marc S. Weinberg, Jonathan J. Bernstein
  • Patent number: 10312175
    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 5, 2018
    Date of Patent: June 4, 2019
    Assignee: 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: 20190157181
    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 5, 2018
    Publication date: May 23, 2019
    Applicant: 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
  • Patent number: 10229839
    Abstract: An method of annealing by: providing a substrate having a III-nitride, sapphire, silicon, diamond, gallium arsenide, or silicon carbide surface; depositing a layer of a transition metal nitride directly on the surface; and annealing the substrate at at least 900° C. in an oxygen-free environment. An article having: a substrate having a III-nitride, sapphire, silicon, diamond, gallium arsenide, or silicon carbide surface; and a layer of a transition metal nitride directly on the surface.
    Type: Grant
    Filed: May 1, 2017
    Date of Patent: March 12, 2019
    Assignee: The United States of America, as Represented by the Secretary of the Navy
    Inventors: Travis J. Anderson, Boris N. Feygelson, Andrew D. Koehler, Karl D. Hobart, Francis J. Kub, Jordan Greenlee
  • Publication number: 20180374944
    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: Application
    Filed: June 25, 2018
    Publication date: December 27, 2018
    Inventors: Travis J. Anderson, Virginia D. Wheeler, Karl D. Hobart, Francis J. Kub
  • Publication number: 20180315820
    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: April 27, 2018
    Publication date: November 1, 2018
    Inventors: Francis J. Kub, Travis J. Anderson, Marko J. Tadjer, Andrew D. Koehler, Karl D. Hobart
  • Publication number: 20180244513
    Abstract: A structure and method of fabricating suspended beam silicon carbide 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: February 28, 2018
    Publication date: August 30, 2018
    Applicant: 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