Patents by Inventor Sandra B. Schujman

Sandra B. Schujman 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).

  • 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
  • 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
  • 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
  • ALUMINUM NITRIDE BULK CRYSTALS HAVING HIGH TRANSPARENCY TO ULTRAVIOLET LIGHT AND METHODS OF FORMING THEM
    Publication number: 20160348273
    Abstract: In various embodiments, methods of forming single-crystal AN include providing a substantially undoped polycrystalline AN ceramic having an oxygen concentration less than approximately 100 ppm, forming a single-crystal bulk AN crystal by a sublimation-recondensation process at a temperature greater than approximately 2000 ° C., and cooling the bulk AN 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: August 15, 2016
    Publication date: December 1, 2016
    Inventors: Sandra B. Schujman, Shailaja P. Rao, Robert T. Bondokov, Kenneth E. Morgan, Glen A. Slack, Leo J. Schowalter
  • Aluminum nitride bulk crystals having high transparency to untraviolet light and methods of forming them
    Patent number: 9447519
    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 16, 2015
    Date of Patent: September 20, 2016
    Assignee: Crystal IS, Inc.
    Inventors: Sandra B. Schujman, Shailaja P. Rao, Robert T. Bondokov, Kenneth E. Morgan, Glen A. Slack, Leo J. Schowalter
  • ALUMINUM NITRIDE BULK CRYSTALS HAVING HIGH TRANSPARENCY TO ULTRAVIOLET LIGHT AND METHODS OF FORMING THEM
    Publication number: 20150218729
    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 16, 2015
    Publication date: August 6, 2015
    Inventors: Sandra B. Schujman, Shailaja P. Rao, Robert T. Bondokov, Kenneth E. Morgan, Glen A. Slack, Leo J. Schowalter
  • Aluminum nitride bulk crystals having high transparency to ultraviolet light and methods of forming them
    Patent number: 9034103
    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: June 30, 2010
    Date of Patent: May 19, 2015
    Assignee: CRYSTAL IS, INC.
    Inventors: Sandra B. Schujman, Shailaja P. Rao, Robert T. Bondokov, Kenneth E. Morgan, Glen A. Slack, Leo J. Schowalter
  • Deep-eutectic melt growth of nitride crystals
    Patent number: 8088220
    Abstract: In accordance with various embodiments, crystalline structures are formed by providing, at a growth temperature, a liquid comprising AlN and having a quality factor greater than approximately 0.14 and forming solid AlN from the liquid, the growth temperature being lower than the melting point of AlN.
    Type: Grant
    Filed: May 23, 2008
    Date of Patent: January 3, 2012
    Assignee: Crystal IS, Inc.
    Inventors: Glen A. Slack, Sandra B. Schujman
  • ALUMINUM NITRIDE BULK CRYSTALS HAVING HIGH TRANSPARENCY TO ULTRAVIOLET LIGHT AND METHODS OF FORMING THEM
    Publication number: 20110008621
    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: June 30, 2010
    Publication date: January 13, 2011
    Inventors: Sandra B. Schujman, Shailaja P. Rao, Robert T. Bondokov, Kenneth E. Morgan, Glen A. Slack, Leo J. Schowalter
  • In-line Fluid Treatment by UV Radiation
    Publication number: 20100314551
    Abstract: A UV source is regulated according to one or more purification parameters to produce a desired germicidal effect in a liquid while minimizing wasted power.
    Type: Application
    Filed: June 10, 2010
    Publication date: December 16, 2010
    Inventors: Timothy J. Bettles, Steven Berger, Sandra B. Schujman, Leo J. Schowalter
  • DEEP-EUTECTIC MELT GROWTH OF NITRIDE CRYSTALS
    Publication number: 20090050050
    Abstract: Single-crystal materials are fabricated from a melt at temperatures below their melting points.
    Type: Application
    Filed: May 23, 2008
    Publication date: February 26, 2009
    Applicant: Crystal IS, Inc.
    Inventors: Glen A. Slack, Sandra B. Schujman