Patents by Inventor James R. Grandusky

James R. Grandusky 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 crystals having low urbach energy and high transparency to deep-ultraviolet wavelengths
    Patent number: 12264410
    Abstract: In various embodiments, single-crystal aluminum nitride boules and substrates have low Urbach energies and/or absorption coefficients at deep-ultraviolet wavelengths. The single-crystal aluminum nitride may function as a platform for the fabrication of light-emitting devices such as light-emitting diodes and lasers. The single-crystal aluminum nitride boules may advantageously have diameters that increase along at least portions of their lengths.
    Type: Grant
    Filed: December 13, 2022
    Date of Patent: April 1, 2025
    Assignee: CRYSTAL IS, INC.
    Inventors: Robert T. Bondokov, James R. Grandusky, Jianfeng Chen, Shichao Wang, Toru Kimura, Thomas Miebach, Keisuke Yamaoka, Leo J. Schowalter
  • Impurity control during formation of aluminum nitride crystals and thermal treatment of aluminum nitride crystals
    Patent number: 11939700
    Abstract: In various embodiments, single-crystal aluminum nitride boules and substrates are formed from the vapor phase with controlled levels of impurities such as carbon. Single-crystal aluminum nitride may be heat treated via quasi-isothermal annealing and controlled cooling to improve its ultraviolet absorption coefficient and/or Urbach energy.
    Type: Grant
    Filed: October 8, 2021
    Date of Patent: March 26, 2024
    Assignee: Crystal IS, Inc.
    Inventors: Robert T. Bondokov, James R. Grandusky, Jianfeng Chen, Shichao Wang, Toru Kimura, Thomas Miebach, Keisuke Yamaoka, Leo J. Schowalter
  • Aluminum nitride single crystals having controllable color and methods of forming them
    Patent number: 11840773
    Abstract: In various embodiments, single-crystal aluminum nitride boules and substrates are highly visibly transparent and have low Urbach energies and/or absorption coefficients at deep-ultraviolet wavelengths. The single-crystal aluminum nitride may function as a platform for the fabrication of light-emitting devices such as light-emitting diodes and lasers.
    Type: Grant
    Filed: December 8, 2021
    Date of Patent: December 12, 2023
    Assignee: Crystal IS, Inc.
    Inventors: Robert T. Bondokov, James R. Grandusky, Jianfeng Chen, Sean P. Branagan, Shichao Wang, Toru Kimura, Thomas Miebach, Keisuke Yamaoka, Leo J. Schowalter
  • Aluminum nitride crystals having low urbach energy and high transparency to deep-ultraviolet wavelengths
    Patent number: 11555256
    Abstract: In various embodiments, single-crystal aluminum nitride boules and substrates have low Urbach energies and/or absorption coefficients at deep-ultraviolet wavelengths. The single-crystal aluminum nitride may function as a platform for the fabrication of light-emitting devices such as light-emitting diodes and lasers.
    Type: Grant
    Filed: June 18, 2019
    Date of Patent: January 17, 2023
    Assignee: CRYSTAL IS, INC.
    Inventors: Robert T. Bondokov, James R. Grandusky, Jianfeng Chen, Shichao Wang, Toru Kimura, Thomas Miebach, Keisuke Yamaoka, Leo J. Schowalter
  • Photon extraction from ultraviolet light-emitting devices
    Patent number: 11515455
    Abstract: In various embodiments, a layer of organic encapsulant is provided over a surface of an ultraviolet (UV) light-emitting semiconductor die, and at least a portion of the encapsulant is exposed to UV light to convert at least some of said portion of the encapsulant into non-stoichiometric silica material. The non-stoichiometric silica material includes silicon, oxygen, and carbon, and a carbon content of the non-stoichiometric silica material is greater than 1 ppm and less than 40 atomic percent.
    Type: Grant
    Filed: October 29, 2020
    Date of Patent: November 29, 2022
    Assignee: CRYSTAL IS, INC.
    Inventors: Ken Kitamura, Masato Toita, Hironori Ishii, Yuting Wang, Leo J. Schowalter, Jianfeng Chen, James R. Grandusky
  • Two-stage seeded growth of large aluminum nitride single crystals
    Patent number: 11384449
    Abstract: In various embodiments, growth of large, high-quality single crystals of aluminum nitride is enabled via a two-stage process utilizing two different crystalline seeds.
    Type: Grant
    Filed: March 13, 2020
    Date of Patent: July 12, 2022
    Assignee: CRYSTAL IS, INC.
    Inventors: Leo J. Schowalter, Robert T. Bondokov, James R. Grandusky
  • Aluminum nitride substrate removal for ultraviolet light-emitting devices
    Patent number: 11355664
    Abstract: In various embodiments, extraction efficiency of light-emitting devices fabricated on aluminum nitride substrates is enhanced via removal of at least a portion of the substrate.
    Type: Grant
    Filed: July 15, 2020
    Date of Patent: June 7, 2022
    Assignee: CRYSTAL IS, INC.
    Inventors: James R. Grandusky, Leo J. Schowalter, Craig Moe
  • Pseudomorphic electronic and optoelectronic devices having planar contacts
    Patent number: 11251330
    Abstract: In various embodiments, light-emitting devices incorporate smooth contact layers and polarization doping (i.e., underlying layers substantially free of dopant impurities) and exhibit high photon extraction efficiencies.
    Type: Grant
    Filed: March 3, 2017
    Date of Patent: February 15, 2022
    Assignee: CRYSTAL IS, INC.
    Inventors: James R. Grandusky, Leo J. Schowalter, Muhammad Jamil, Mark C. Mendrick, Shawn R. Gibb
  • Impurity control during formation of aluminum nitride crystals and thermal treatment of aluminum nitride crystals
    Patent number: 11168411
    Abstract: In various embodiments, single-crystal aluminum nitride boules and substrates are formed from the vapor phase with controlled levels of impurities such as carbon. Single-crystal aluminum nitride may be heat treated via quasi-isothermal annealing and controlled cooling to improve its ultraviolet absorption coefficient and/or Urbach energy.
    Type: Grant
    Filed: June 18, 2019
    Date of Patent: November 9, 2021
    Assignee: CRYSTAL IS, INC.
    Inventors: Robert T. Bondokov, James R. Grandusky, Jianfeng Chen, Shichao Wang, Toru Kimura, Thomas Miebach, Keisuke Yamaoka, Leo J. Schowalter
  • Photon extraction from nitride ultraviolet light-emitting devices
    Patent number: 10971665
    Abstract: In various embodiments, a rigid lens is attached to a light-emitting semiconductor die via a layer of encapsulant having a thickness insufficient to prevent propagation of thermal expansion mismatch-induced strain between the rigid lens and the semiconductor die.
    Type: Grant
    Filed: February 26, 2020
    Date of Patent: April 6, 2021
    Assignee: CRYSTAL IS, INC.
    Inventors: Leo J. Schowalter, Jianfeng Chen, James R. Grandusky
  • Photon extraction from ultraviolet light-emitting devices
    Patent number: 10854797
    Abstract: In various embodiments, a layer of organic encapsulant is provided over a surface of an ultraviolet (UV) light-emitting semiconductor die, and at least a portion of the encapsulant is exposed to UV light to convert at least some of said portion of the encapsulant into non-stoichiometric silica material. The non-stoichiometric silica material includes silicon, oxygen, and carbon, and a carbon content of the non-stoichiometric silica material is greater than 1 ppm and less than 40 atomic percent.
    Type: Grant
    Filed: May 24, 2019
    Date of Patent: December 1, 2020
    Assignee: CRYSTALIS, INC.
    Inventors: Ken Kitamura, Masato Toita, Hironori Ishii, Yuting Wang, Leo J. Schowalter, Jianfeng Chen, James R. Grandusky
  • Aluminum nitride substrate removal for ultraviolet light-emitting devices
    Patent number: 10756234
    Abstract: In various embodiments, extraction efficiency of light-emitting devices fabricated on aluminum nitride substrates is enhanced via removal of at least a portion of the substrate.
    Type: Grant
    Filed: May 11, 2018
    Date of Patent: August 25, 2020
    Assignee: CRYSTAL IS, INC.
    Inventors: James R. Grandusky, Leo J. Schowalter, Craig Moe
  • Ultraviolet light-emitting devices incorporating graded layers and compositional offsets
    Patent number: 10700237
    Abstract: In various embodiments, light-emitting devices incorporate graded layers with compositional offsets at one or both end points of the graded layer to promote formation of two-dimensional carrier gases and polarization doping, thereby enhancing device performance.
    Type: Grant
    Filed: January 4, 2019
    Date of Patent: June 30, 2020
    Assignee: CRYSTAL IS, INC.
    Inventors: Craig Moe, James R. Grandusky, Shawn R. Gibb, Leo J. Schowalter, Kosuke Sato, Tomohiro Morishita
  • Photon extraction from nitride ultraviolet light-emitting devices
    Patent number: 10615322
    Abstract: In various embodiments, a rigid lens is attached to a light-emitting semiconductor die via a layer of encapsulant having a thickness insufficient to prevent propagation of thermal expansion mismatch-induced strain between the rigid lens and the semiconductor die.
    Type: Grant
    Filed: August 9, 2018
    Date of Patent: April 7, 2020
    Assignee: CRYSTAL IS, INC.
    Inventors: Leo J. Schowalter, Jianfeng Chen, James R. Grandusky
  • Two-stage seeded growth of large aluminum nitride single crystals
    Patent number: 10612156
    Abstract: In various embodiments, growth of large, high-quality single crystals of aluminum nitride is enabled via a two-stage process utilizing two different crystalline seeds.
    Type: Grant
    Filed: July 17, 2019
    Date of Patent: April 7, 2020
    Assignee: Crystal IS, Inc.
    Inventors: Leo J. Schowalter, Robert T. Bondokov, James R. Grandusky
  • THICK PSEUDOMORPHIC NITRIDE EPITAXIAL LAYERS
    Publication number: 20200058491
    Abstract: In various embodiments, a semiconductor device includes an aluminum nitride single-crystal substrate, a pseudomorphic strained layer disposed thereover that comprises at least one of AN, GaN, InN, or an alloy thereof, and, disposed over the strained layer, a semiconductor layer that is lattice-mismatched to the substrate and substantially relaxed.
    Type: Application
    Filed: September 3, 2019
    Publication date: February 20, 2020
    Inventors: James R. Grandusky, Leo J. Schowalter, Shawn R. Gibb, Joseph A. Smart, Shiwen Liu
  • PHOTON EXTRACTION FROM ULTRAVIOLET LIGHT-EMITTING DEVICES
    Publication number: 20190348581
    Abstract: In various embodiments, a layer of organic encapsulant is provided over a surface of an ultraviolet (UV) light-emitting semiconductor die, and at least a portion of the encapsulant is exposed to UV light to convert at least some of said portion of the encapsulant into non-stoichiometric silica material. The non-stoichiometric silica material includes silicon, oxygen, and carbon, and a carbon content of the non-stoichiometric silica material is greater than 1 ppm and less than 40 atomic percent.
    Type: Application
    Filed: May 24, 2019
    Publication date: November 14, 2019
    Inventors: Ken Kitamura, Masato Toita, Hironori Ishii, Yuting Wang, Leo J. Schowalter, Jianfeng Chen, James R. Grandusky
  • Thick pseudomorphic nitride epitaxial layers
    Patent number: 10446391
    Abstract: In various embodiments, a semiconductor device includes an aluminum nitride single-crystal substrate, a pseudomorphic strained layer disposed thereover that comprises at least one of AlN, GaN, InN, or an alloy thereof, and, disposed over the strained layer, a semiconductor layer that is lattice-mismatched to the substrate and substantially relaxed.
    Type: Grant
    Filed: November 17, 2011
    Date of Patent: October 15, 2019
    Assignee: CRYSTAL IS, INC.
    Inventors: James R. Grandusky, Leo J. Schowalter, Shawn R. Gibb, Joseph A. Smart, Shiwen Liu
  • Two-stage seeded growth of large aluminum nitride single crystals
    Patent number: 10407798
    Abstract: In various embodiments, growth of large, high-quality single crystals of aluminum nitride is enabled via a two-stage process utilizing two different crystalline seeds.
    Type: Grant
    Filed: June 14, 2018
    Date of Patent: September 10, 2019
    Assignee: CRYSTAL IS, INC.
    Inventors: Leo J. Schowalter, Robert T. Bondokov, James R. Grandusky
  • Photon extraction from ultraviolet light-emitting devices
    Patent number: 10347805
    Abstract: In various embodiments, a layer of organic encapsulant is provided over a surface of an ultraviolet (UV) light-emitting semiconductor die, and at least a portion of the encapsulant is exposed to UV light to convert at least some of said portion of the encapsulant into non-stoichiometric silica material. The non-stoichiometric silica material includes silicon, oxygen, and carbon, and a carbon content of the non-stoichiometric silica material is greater than 1 ppm and less than 40 atomic percent.
    Type: Grant
    Filed: February 16, 2018
    Date of Patent: July 9, 2019
    Assignee: CRYSTAL IS, INC.
    Inventors: Ken Kitamura, Masato Toita, Hironori Ishii, Yuting Wang, Leo J. Schowalter, Jianfeng Chen, James R. Grandusky