Patents by Inventor Boris N. Feigelson

Boris N. Feigelson 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: 20220254639
    Abstract: A method for activating implanted dopants and repairing damage to dopant-implanted GaN to form n-type or p-type GaN. A GaN substrate is implanted with n- or p-type ions and is subjected to a high-temperature anneal to activate the implanted dopants and to produce planar n- or p-type doped areas within the GaN having an activated dopant concentration of about 1018-1022 cm?3. An initial annealing at a temperature at which the GaN is stable at a predetermined process temperature for a predetermined time can be conducted before the high-temperature anneal. A thermally stable cap can be applied to the GaN substrate to suppress nitrogen evolution from the GaN surface during the high-temperature annealing step. The high-temperature annealing can be conducted under N2 pressure to increase the stability of the GaN. The annealing can be conducted using laser annealing or rapid thermal annealing (RTA).
    Type: Application
    Filed: January 26, 2022
    Publication date: August 11, 2022
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Travis J. Anderson, James C. Gallagher, Marko J. Tadjer, Alan G. Jacobs, Boris N. Feigelson
  • Publication number: 20220059352
    Abstract: A method for activating implanted dopants and repairing damage to dopant-implanted GaN to form n-type or p-type GaN. A GaN substrate is implanted with n- or p-type ions and is subjected to a high-temperature anneal to activate the implanted dopants and to produce planar n- or p-type doped areas within the GaN having an activated dopant concentration of about 1018-1022 cm?3. An initial annealing at a temperature at which the GaN is stable at a predetermined process temperature for a predetermined time can be conducted before the high-temperature anneal. A thermally stable cap can be applied to the GaN substrate to suppress nitrogen evolution from the GaN surface during the high-temperature annealing step. The high-temperature annealing can be conducted under N2 pressure to increase the stability of the GaN. The annealing can be conducted using laser annealing or rapid thermal annealing (RTA).
    Type: Application
    Filed: November 8, 2021
    Publication date: February 24, 2022
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Travis J. Anderson, James C. Gallagher, Marko J. Tadjer, Alan G. Jacobs, Boris N. Feigelson
  • Publication number: 20220059353
    Abstract: A method for activating implanted dopants and repairing damage to dopant-implanted GaN to form n-type or p-type GaN. A GaN substrate is implanted with n- or p-type ions and is subjected to a high-temperature anneal to activate the implanted dopants and to produce planar n- or p-type doped areas within the GaN having an activated dopant concentration of about 1018-1022 cm?3. An initial annealing at a temperature at which the GaN is stable at a predetermined process temperature for a predetermined time can be conducted before the high-temperature anneal. A thermally stable cap can be applied to the GaN substrate to suppress nitrogen evolution from the GaN surface during the high-temperature annealing step. The high-temperature annealing can be conducted under N2 pressure to increase the stability of the GaN. The annealing can be conducted using laser annealing or rapid thermal annealing (RTA).
    Type: Application
    Filed: November 8, 2021
    Publication date: February 24, 2022
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Travis J. Anderson, James C. Gallagher, Marko J. Tadjer, Alan G. Jacobs, Boris N. Feigelson
  • Publication number: 20210400777
    Abstract: RF susceptors manufactured by means of 3D printing. 3D-printed susceptors in accordance with the invention include susceptors having solid or mesh walls, where the susceptors are in the form of hollow cylinders, pyramids, spheres, hemispheres, ellipsoids, paraboloids, toroids, or prisms; flat planes; or other hollow or solid three-dimensional shapes. The 3D-printed susceptors can be formed from any suitable starting material, such as tungsten powder, graphite, silicon carbide, molybdenum powder, tantalum powder, rhenium powder, or alloys thereof, or can be formed such that some portions of the susceptors are formed from one or more materials while other portions are formed from different material(s).
    Type: Application
    Filed: June 15, 2021
    Publication date: December 23, 2021
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Alan G. Jacobs, Boris N. Feigelson
  • Patent number: 11201058
    Abstract: A method for activating implanted dopants and repairing damage to dopant-implanted GaN to form n-type or p-type GaN. A GaN substrate is implanted with n- or p-type ions and is subjected to a high-temperature anneal to activate the implanted dopants and to produce planar n- or p-type doped areas within the GaN having an activated dopant concentration of about 1018-1022 cm?3. An initial annealing at a temperature at which the GaN is stable at a predetermined process temperature for a predetermined time can be conducted before the high-temperature anneal. A thermally stable cap can be applied to the GaN substrate to suppress nitrogen evolution from the GaN surface during the high-temperature annealing step. The high-temperature annealing can be conducted under N2 pressure to increase the stability of the GaN. The annealing can be conducted using laser annealing or rapid thermal annealing (RTA).
    Type: Grant
    Filed: July 13, 2020
    Date of Patent: December 14, 2021
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Travis J. Anderson, James C. Gallagher, Marko J. Tadjer, Alan G. Jacobs, Boris N. Feigelson
  • Patent number: 11075049
    Abstract: A thermionic dispenser cathode having a refractory metal matrix with scandium and barium compounds in contact with the metal matrix and methods for forming the same. The invention utilizes atomic layer deposition (ALD) to form a nanoscale, uniform, conformal distribution of a scandium compound on tungsten surfaces and further utilizes in situ high pressure consolidation/impregnation to enhance impregnation of a BaO—CaO—Al2O3 based emissive mixture into the scandate-coated tungsten matrix or to sinter a tungsten/scandate/barium composite structure. The result is a tungsten-scandate thermionic cathode having improved emission.
    Type: Grant
    Filed: October 15, 2019
    Date of Patent: July 27, 2021
    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
  • Publication number: 20210028020
    Abstract: A method for activating implanted dopants and repairing damage to dopant-implanted GaN to form n-type or p-type GaN. A GaN substrate is implanted with n- or p-type ions and is subjected to a high-temperature anneal to activate the implanted dopants and to produce planar n- or p-type doped areas within the GaN having an activated dopant concentration of about 1018-1022 cm?3. An initial annealing at a temperature at which the GaN is stable at a predetermined process temperature for a predetermined time can be conducted before the high-temperature anneal. A thermally stable cap can be applied to the GaN substrate to suppress nitrogen evolution from the GaN surface during the high-temperature annealing step. The high-temperature annealing can be conducted under N2 pressure to increase the stability of the GaN. The annealing can be conducted using laser annealing or rapid thermal annealing (RTA).
    Type: Application
    Filed: July 13, 2020
    Publication date: January 28, 2021
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Travis J. Anderson, James C. Gallagher, Marko J. Tadjer, Alan G. Jacobs, Boris N. Feigelson
  • 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: 10751801
    Abstract: A new Enhanced High Pressure Sintering (EHPS) method for making three-dimensional fully dense nanostructures and nano-heterostructures formed from nanoparticle powders, and three-dimensional fully dense nanostructures and nano-heterostructures formed using that method. A nanoparticle powder is placed into a reaction chamber and is treated at an elevated temperature under a gas flow to produce a cleaned powder. The cleaned powder is formed into a low density green compact which is then sintered at a temperature below conventional sintering temperatures to produce a fully dense bulk material having a retained nanostructure or nano-heterostructure corresponding to the nanostructure of the constituent nanoparticles. All steps are performed without exposing the nanoparticle powder to the ambient.
    Type: Grant
    Filed: November 14, 2014
    Date of Patent: August 25, 2020
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Boris N. Feigelson, James A. Wollmershauser
  • Patent number: 10562784
    Abstract: A process for producing metastable nanocrystalline alpha-alumina (?-Al2O3) having particle sizes smaller than 12 nm. Starting crystallites of ?-Al2O3 having a particle size larger than 12 nm, typically on the order of about 50 nm, are ball-milled at low temperatures to produce a nanocrystalline ?-Al2O3 powder having a particle size of less than 12 nm, i.e., below the theoretical room temperature thermodynamic size limit at which ?-Al2O3 changes phase to ?-Al2O3, wherein the powder remains in the ?-Al2O3 phase at all times.
    Type: Grant
    Filed: May 31, 2019
    Date of Patent: February 18, 2020
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: James A. Wollmershauser, John Drazin, Dana A. Kazerooni, Boris N. Feigelson, Edward P. Gorzkowski, III
  • Publication number: 20200043691
    Abstract: A thermionic dispenser cathode having a refractory metal matrix with scandium and barium compounds in contact with the metal matrix and methods for forming the same. The invention utilizes atomic layer deposition (ALD) to form a nanoscale, uniform, conformal distribution of a scandium compound on tungsten surfaces and further utilizes in situ high pressure consolidation/impregnation to enhance impregnation of a BaO—CaO—Al2O3 based emissive mixture into the scandate-coated tungsten matrix or to sinter a tungsten/scandate/barium composite structure. The result is a tungsten-scandate thermionic cathode having improved emission.
    Type: Application
    Filed: October 15, 2019
    Publication date: February 6, 2020
    Applicant: 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
  • 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: 10497530
    Abstract: A thermionic dispenser cathode having a refractory metal matrix with scandium and barium compounds in contact with the metal matrix and methods for forming the same. The invention utilizes atomic layer deposition (ALD) to form a nanoscale, uniform, conformal distribution of a scandium compound on tungsten surfaces and further utilizes in situ high pressure consolidation/impregnation to enhance impregnation of a BaO—CaO—Al2O3 based emissive mixture into the scandate-coated tungsten matrix or to sinter a tungsten/scandate/barium composite structure. The result is a tungsten-scandate thermionic cathode having improved emission.
    Type: Grant
    Filed: April 8, 2016
    Date of Patent: December 3, 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
  • 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
  • Patent number: 10403509
    Abstract: A method for removing existing basal plane dislocations (BPDs) from silicon carbide epilayers by using a pulsed rapid thermal annealing process where the BPDs in the epilayers were eliminated while preserving the epitaxial surface. This high temperature, high pressure method uses silicon carbide epitaxial layers with a carbon cap to protect the surface. These capped epilayers are subjected to a plurality of rapid heating and cooling cycles.
    Type: Grant
    Filed: April 6, 2015
    Date of Patent: September 3, 2019
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Marko J. Tadjer, Boris N. Feigelson, Nadeemullah A. Mahadik, Robert E. Stahlbush, Eugene A. Imhoff, Jordan Greenlee
  • Patent number: 10351435
    Abstract: A process for producing metastable nanocrystalline alpha-alumina (?-Al2O3) having particle sizes smaller than 12 nm. Starting crystallites of ?-Al2O3 having a particle size larger than 12 nm, typically on the order of about 50 nm, are ball-milled at low temperatures to produce a nanocrystalline ?-Al2O3 powder having a particle size of less than 12 nm, i.e., below the theoretical room temperature thermodynamic size limit at which ?-Al2O3 changes phase to ?-Al2O3, wherein the powder remains in the ?-Al2O3 phase at all times.
    Type: Grant
    Filed: October 12, 2017
    Date of Patent: July 16, 2019
    Assignee: The United States of America, as represented by the Secretary of the Navy
    Inventors: James A. Wollmershauser, John Drazin, Dana A. Kazerooni, Boris N. Feigelson, Edward P. Gorzkowski, III
  • Publication number: 20180111841
    Abstract: A process for producing metastable nanocrystalline alpha-alumina (?-Al2O3) having particle sizes smaller than 12 nm. Starting crystallites of ?-Al2O3 having a particle size larger than 12 nm, typically on the order of about 50 nm, are ball-milled at low temperatures to produce a nanocrystalline ?-Al2O3 powder having a particle size of less than 12 nm, i.e., below the theoretical room temperature thermodynamic size limit at which ?-Al2O3 changes phase to ?-Al2O3, wherein the powder remains in the ?-Al2O3 phase at all times.
    Type: Application
    Filed: October 12, 2017
    Publication date: April 26, 2018
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: James A. Wollmershauser, John Drazin, Dana A. Kazerooni, Boris N. Feigelson, Edward P. Gorzkowski, III
  • Publication number: 20170073276
    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: Application
    Filed: September 9, 2016
    Publication date: March 16, 2017
    Applicant: 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: 9543168
    Abstract: A symmetric multicycle rapid thermal annealing (SMRTA) method for annealing a semiconductor material without the material decomposing. The SMRTA method includes a first long-time annealing at a first temperature at which the material is thermodynamically stable, followed by multicycle rapid thermal annealing (MRTA) at temperatures at which the material is not thermodynamically stable, followed in turn by a second long-time annealing at a second temperature at which the material is thermodynamically stable. The SMRTA method can be used to form p-type and n-type semiconductor regions in doped III-nitride semiconductors, SiC, and diamond.
    Type: Grant
    Filed: February 4, 2016
    Date of Patent: January 10, 2017
    Assignee: The United States of America, as represented by the Secretary of the Navy
    Inventors: Boris N. Feigelson, Jordan Greenlee, Travis J. Anderson, Francis J. Kub
  • Publication number: 20160300684
    Abstract: A thermionic dispenser cathode having a refractory metal matrix with scandium and barium compounds in contact with the metal matrix and methods for forming the same. The invention utilizes atomic layer deposition (ALD) to form a nanoscale, uniform, conformal distribution of a scandium compound on tungsten surfaces and further utilizes in situ high pressure consolidation/impregnation to enhance impregnation of a BaO-CaO-Al2O3 based emissive mixture into the scandate-coated tungsten matrix or to sinter a tungsten/scandate/barium composite structure. The result is a tungsten-scandate thermionic cathode having improved emission.
    Type: Application
    Filed: April 8, 2016
    Publication date: October 13, 2016
    Applicant: 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