Patents by Inventor Glen Slack

Glen Slack 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).

  • Large aluminum nitride crystals with reduced defects and methods of making them
    Patent number: 11225731
    Abstract: Reducing the microvoid (MV) density in AlN ameliorates numerous problems related to cracking during crystal growth, etch pit generation during the polishing, reduction of the optical transparency in an AlN wafer, and, possibly, growth pit formation during epitaxial growth of AlN and/or AlGaN. This facilitates practical crystal production strategies and the formation of large, bulk AlN crystals with low defect densities—e.g., a dislocation density below 104 cm?2 and an inclusion density below 104 cm?3 and/or a MV density below 104 cm?3.
    Type: Grant
    Filed: February 8, 2017
    Date of Patent: January 18, 2022
    Assignee: CRYSTAL IS, INC.
    Inventors: Robert Bondokov, Kenneth E. Morgan, Glen A. Slack, Leo J. Schowalter
  • Doped aluminum nitride crystals and methods of making them
    Patent number: 11183567
    Abstract: Fabrication of doped AlN crystals and/or AlGaN epitaxial layers with high conductivity and mobility is accomplished by, for example, forming mixed crystals including a plurality of impurity species and electrically activating at least a portion of the crystal.
    Type: Grant
    Filed: May 15, 2020
    Date of Patent: November 23, 2021
    Assignee: Crystal IS, Inc.
    Inventors: Glen A. Slack, Leo J. Schowalter
  • Defect reduction in seeded aluminum nitride crystal growth
    Patent number: 11124892
    Abstract: Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density ?100 cm?2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.
    Type: Grant
    Filed: May 22, 2020
    Date of Patent: September 21, 2021
    Assignee: CRYSTAL IS, INC.
    Inventors: Robert T. Bondokov, Kenneth E. Morgan, Leo J. Schowalter, Glen A. Slack
  • Defect reduction in seeded aluminum nitride crystal growth
    Patent number: 11015263
    Abstract: Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density?100 cm?2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.
    Type: Grant
    Filed: July 9, 2019
    Date of Patent: May 25, 2021
    Assignee: CRYSTAL IS, INC.
    Inventors: Robert T. Bondokov, Leo J. Schowalter, Kenneth Morgan, Glen A. Slack, Shailaja P. Rao, Shawn Robert Gibb
  • DEFECT REDUCTION IN SEEDED ALUMINUM NITRIDE CRYSTAL GROWTH
    Publication number: 20200354852
    Abstract: Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density ?100 cm?2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.
    Type: Application
    Filed: May 22, 2020
    Publication date: November 12, 2020
    Inventors: Robert T. Bondokov, Kenneth E. Morgan, Leo J. Schowalter, Glen A. Slack
  • DOPED ALUMINUM NITRIDE CRYSTALS AND METHODS OF MAKING THEM
    Publication number: 20200350411
    Abstract: Fabrication of doped AlN crystals and/or AlGaN epitaxial layers with high conductivity and mobility is accomplished by, for example, forming mixed crystals including a plurality of impurity species and electrically activating at least a portion of the crystal.
    Type: Application
    Filed: May 15, 2020
    Publication date: November 5, 2020
    Inventors: Glen A. SLACK, Leo J. SCHOWALTER
  • Aluminum nitride bulk crystals having high transparency to ultraviolet light and methods of forming them
    Patent number: 10801127
    Abstract: In various embodiments, methods of forming single-crystal AlN include providing a substantially undoped polycrystalline AlN ceramic having an oxygen concentration less than approximately 100 ppm, forming a single-crystal bulk AlN crystal by a sublimation-recondensation process at a temperature greater than approximately 2000° C., and cooling the bulk AlN crystal to a first temperature between approximately 1500° C. and approximately 1800° C. at a first rate less than approximately 250° C./hour.
    Type: Grant
    Filed: April 26, 2019
    Date of Patent: October 13, 2020
    Assignee: CRYSTAL IS, INC.
    Inventors: Sandra B. Schujman, Shailaja P. Rao, Robert T. Bondokov, Kenneth E. Morgan, Glen A. Slack, Leo J. Schowalter
  • Defect reduction in seeded aluminum nitride crystal growth
    Patent number: 10697085
    Abstract: Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density?100 cm=2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.
    Type: Grant
    Filed: October 15, 2018
    Date of Patent: June 30, 2020
    Assignee: CRYSTAL IS, INC.
    Inventors: Robert T. Bondokov, Kenneth E. Morgan, Leo J. Schowalter, Glen A. Slack
  • Doped aluminum nitride crystals and methods of making them
    Patent number: 10692980
    Abstract: Fabrication of doped AlN crystals and/or AlGaN epitaxial layers with high conductivity and mobility is accomplished by, for example, forming mixed crystals including a plurality of impurity species and electrically activating at least a portion of the crystal.
    Type: Grant
    Filed: August 6, 2018
    Date of Patent: June 23, 2020
    Assignee: CRYSTAL IS, INC.
    Inventors: Glen A. Slack, Leo J. Schowalter
  • DEFECT REDUCTION IN SEEDED ALUMINUM NITRIDE CRYSTAL GROWTH
    Publication number: 20200002841
    Abstract: Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density?100 cm?2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.
    Type: Application
    Filed: July 9, 2019
    Publication date: January 2, 2020
    Inventors: Robert T. Bondokov, Leo J. Schowalter, Kenneth Morgan, Glen A. Slack, Shailaja P. Rao, Shawn Robert Gibb
  • ALUMINUM NITRIDE BULK CRYSTALS HAVING HIGH TRANSPARENCY TO ULTRAVIOLET LIGHT AND METHODS OF FORMING THEM
    Publication number: 20190316272
    Abstract: In various embodiments, methods of forming single-crystal AlN include providing a substantially undoped polycrystalline AlN ceramic having an oxygen concentration less than approximately 100 ppm, forming a single-crystal bulk AlN crystal by a sublimation-recondensation process at a temperature greater than approximately 2000° C., and cooling the bulk AlN crystal to a first temperature between approximately 1500° C. and approximately 1800° C. at a first rate less than approximately 250° C./hour.
    Type: Application
    Filed: April 26, 2019
    Publication date: October 17, 2019
    Inventors: Sandra B. Schujman, Shailaja P. Rao, Robert T. Bondokov, Kenneth E. Morgan, Glen A. Slack, Leo J. Schowalter
  • Defect reduction in seeded aluminum nitride crystal growth
    Patent number: 10392722
    Abstract: Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density ?100 cm?2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.
    Type: Grant
    Filed: August 24, 2017
    Date of Patent: August 27, 2019
    Assignee: CRYSTAL IS, INC.
    Inventors: Robert T. Bondokov, Leo J. Schowalter, Kenneth Morgan, Glen A. Slack, Shailaja P. Rao, Shawn Robert Gibb
  • Aluminum nitride bulk crystals having high transparency to ultraviolet light and methods of forming them
    Patent number: 10316428
    Abstract: In various embodiments, methods of forming single-crystal AlN include providing a substantially undoped polycrystalline AlN ceramic having an oxygen concentration less than approximately 100 ppm, forming a single-crystal bulk AlN crystal by a sublimation-recondensation process at a temperature greater than approximately 2000° C., and cooling the bulk AlN crystal to a first temperature between approximately 1500° C. and approximately 1800° C. at a first rate less than approximately 250° C./hour.
    Type: Grant
    Filed: August 15, 2016
    Date of Patent: June 11, 2019
    Assignee: Crystal IS, Inc.
    Inventors: Sandra B. Schujman, Shailaja P. Rao, Robert T. Bondokov, Kenneth E. Morgan, Glen A. Slack, Leo J. Schowalter
  • DEFECT REDUCTION IN SEEDED ALUMINUM NITRIDE CRYSTAL GROWTH
    Publication number: 20190106808
    Abstract: Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density ?100 cm=2, Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.
    Type: Application
    Filed: October 15, 2018
    Publication date: April 11, 2019
    Inventors: Robert T. Bondokov, Kenneth E. Morgan, Leo J. Schowalter, Glen A. Slack
  • DOPED ALUMINUM NITRIDE CRYSTALS AND METHODS OF MAKING THEM
    Publication number: 20190035898
    Abstract: Fabrication of doped AlN crystals and/or AlGaN epitaxial layers with high conductivity and mobility is accomplished by, for example, forming mixed crystals including a plurality of impurity species and electrically activating at least a portion of the crystal.
    Type: Application
    Filed: August 6, 2018
    Publication date: January 31, 2019
    Inventors: Glen A. SLACK, Leo J. SCHOWALTER
  • Defect reduction in seeded aluminum nitride crystal growth
    Patent number: 10125432
    Abstract: Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density?100 cm?2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.
    Type: Grant
    Filed: March 20, 2017
    Date of Patent: November 13, 2018
    Assignee: CRYSTAL IS , INC.
    Inventors: Robert T. Bondokov, Kenneth E. Morgan, Leo J. Schowalter, Glen A. Slack
  • Doped aluminum nitride crystals and methods of making them
    Patent number: 10068973
    Abstract: Fabrication of doped AlN crystals and/or AlGaN epitaxial layers with high conductivity and mobility is accomplished by, for example, forming mixed crystals including a plurality of impurity species and electrically activating at least a portion of the crystal.
    Type: Grant
    Filed: November 10, 2016
    Date of Patent: September 4, 2018
    Assignee: CRYSTAL IS, INC.
    Inventors: Glen A. Slack, Leo J. Schowalter
  • Method and apparatus for producing large, single-crystals of aluminum nitride
    Patent number: 9970127
    Abstract: Bulk single crystals of AlN having a diameter greater than about 25 mm and dislocation densities of about 10,000 cm?2 or less and high-quality AlN substrates having surfaces of any desired crystallographic orientation fabricated from these bulk crystals.
    Type: Grant
    Filed: August 8, 2016
    Date of Patent: May 15, 2018
    Assignee: CRYSTAL IS, INC.
    Inventors: Leo Schowalter, Glen A. Slack, Juan Carlos Rojo, Robert T. Bondokov, Kenneth E. Morgan, Joseph A. Smart
  • DEFECT REDUCTION IN SEEDED ALUMINUM NITRIDE CRYSTAL GROWTH
    Publication number: 20170350036
    Abstract: Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density?100 cm?2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.
    Type: Application
    Filed: August 24, 2017
    Publication date: December 7, 2017
    Inventors: Robert T. Bondokov, Leo J. Schowalter, Kenneth Morgan, Glen A. Slack, Shailaja P. Rao, Shawn Robert Gibb
  • Defect reduction in seeded aluminum nitride crystal growth
    Patent number: 9771666
    Abstract: Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density?100 cm?2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.
    Type: Grant
    Filed: April 13, 2015
    Date of Patent: September 26, 2017
    Assignee: CRYSTAL IS, INC.
    Inventors: Robert T. Bondokov, Leo J. Schowalter, Kenneth Morgan, Glen A. Slack, Shailaja P. Rao, Shawn Robert Gibb