Patents by Inventor Steven Griffiths

Steven Griffiths 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: 20250006491
    Abstract: Silicon carbide (SiC) materials including SiC wafers and SiC boules and related methods are disclosed that provide large dimension SiC wafers with reduced crystallographic stress. Growth conditions for SiC materials include maintaining a generally convex growth surface of SiC crystals, adjusting differences in front-side to back-side thermal profiles of growing SiC crystals, supplying sufficient source flux to allow commercially viable growth rates for SiC crystals, and reducing the inclusion of contaminants or non-SiC particles in SiC source materials and corresponding SiC crystals. By forming larger dimension SiC crystals that exhibit lower crystallographic stress, overall dislocation densities that are associated with missing or additional planes of atoms may be reduced, thereby improving crystal quality and usable SiC crystal growth heights.
    Type: Application
    Filed: September 9, 2024
    Publication date: January 2, 2025
    Inventors: Yuri Khlebnikov, Varad R. Sakhalkar, Caleb A. Kent, Valeri F. Tsvetkov, Michael J. Paisley, Oleksandr Kramarenko, Matthew David Conrad, Eugene Deyneka, Steven Griffiths, Simon Bubel, Adrian R. Powell, Robert Tyler Leonard, Elif Balkas, Curt Progl, Michael Fusco, Alexander Shveyd, Kathy Doverspike, Lukas Nattermann
  • Publication number: 20240352622
    Abstract: Silicon carbide (SiC) wafers and related methods are disclosed that include large diameter SiC wafers with wafer shape characteristics suitable for semiconductor manufacturing. Large diameter SiC wafers are disclosed that have reduced deformation related to stress and strain effects associated with forming such SiC wafers. As described herein, wafer shape and flatness characteristics may be improved by reducing crystallographic stress profiles during growth of SiC crystal boules or ingots. Wafer shape and flatness characteristics may also be improved after individual SiC wafers have been separated from corresponding SiC crystal boules. In this regard, SiC wafers and related methods are disclosed that include large diameter SiC wafers with suitable crystal quality and wafer shape characteristics including low values for wafer bow, warp, and thickness variation.
    Type: Application
    Filed: July 3, 2024
    Publication date: October 24, 2024
    Inventors: Yuri Khlebnikov, Varad R. Sakhalkar, Caleb A. Kent, Valeri F. Tsvetkov, Michael J. Paisley, Oleksandr Kramarenko, Matthew David Conrad, Eugene Deyneka, Steven Griffiths, Simon Bubel, Adrian R. Powell, Robert Tyler Leonard, Elif Balkas, Jeffrey C. Seaman
  • Patent number: 12125701
    Abstract: Silicon carbide (SiC) materials including SiC wafers and SiC boules and related methods are disclosed that provide large dimension SiC wafers with reduced crystallographic stress. Growth conditions for SiC materials include maintaining a generally convex growth surface of SiC crystals, adjusting differences in front-side to back-side thermal profiles of growing SiC crystals, supplying sufficient source flux to allow commercially viable growth rates for SiC crystals, and reducing the inclusion of contaminants or non-SiC particles in SiC source materials and corresponding SiC crystals. By forming larger dimension SiC crystals that exhibit lower crystallographic stress, overall dislocation densities that are associated with missing or additional planes of atoms may be reduced, thereby improving crystal quality and usable SiC crystal growth heights.
    Type: Grant
    Filed: December 15, 2020
    Date of Patent: October 22, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Yuri Khlebnikov, Varad R. Sakhalkar, Caleb A. Kent, Valeri F. Tsvetkov, Michael J. Paisley, Oleksandr Kramarenko, Matthew David Conrad, Eugene Deyneka, Steven Griffiths, Simon Bubel, Adrian R. Powell, Robert Tyler Leonard, Elif Balkas, Curt Progl, Michael Fusco, Alexander Shveyd, Kathy Doverspike, Lukas Nattermann
  • Patent number: 12054850
    Abstract: Silicon carbide (SiC) wafers and related methods are disclosed that include large diameter SiC wafers with wafer shape characteristics suitable for semiconductor manufacturing. Large diameter SiC wafers are disclosed that have reduced deformation related to stress and strain effects associated with forming such SiC wafers. As described herein, wafer shape and flatness characteristics may be improved by reducing crystallographic stress profiles during growth of SiC crystal boules or ingots. Wafer shape and flatness characteristics may also be improved after individual SiC wafers have been separated from corresponding SiC crystal boules. In this regard, SiC wafers and related methods are disclosed that include large diameter SiC wafers with suitable crystal quality and wafer shape characteristics including low values for wafer bow, warp, and thickness variation.
    Type: Grant
    Filed: December 17, 2020
    Date of Patent: August 6, 2024
    Assignee: WOLFSPEED, INC.
    Inventors: Yuri Khlebnikov, Varad R. Sakhalkar, Caleb A. Kent, Valeri F. Tsvetkov, Michael J. Paisley, Oleksandr Kramarenko, Matthew David Conrad, Eugene Deyneka, Steven Griffiths, Simon Bubel, Adrian R. Powell, Robert Tyler Leonard, Elif Balkas, Jeffrey C. Seaman
  • Patent number: 11519098
    Abstract: Silicon carbide (SiC) wafers, SiC boules, and related methods are disclosed that provide improved dislocation distributions. SiC boules are provided that demonstrate reduced dislocation densities and improved dislocation uniformity across longer boule lengths. Corresponding SiC wafers include reduced total dislocation density (TDD) values and improved TDD radial uniformity. Growth conditions for SiC crystalline materials include providing source materials in oversaturated quantities where amounts of the source materials present during growth are significantly higher than what would typically be required. Such SiC crystalline materials and related methods are suitable for providing large diameter SiC boules and corresponding SiC wafers with improved crystalline quality.
    Type: Grant
    Filed: January 29, 2020
    Date of Patent: December 6, 2022
    Assignee: Wolfspeed, Inc.
    Inventors: Yuri Khlebnikov, Robert T. Leonard, Elif Balkas, Steven Griffiths, Valeri Tsvetkov, Michael Paisley
  • Publication number: 20220189768
    Abstract: Silicon carbide (SiC) materials including SiC wafers and SiC boules and related methods are disclosed that provide large dimension SiC wafers with reduced crystallographic stress. Growth conditions for SiC materials include maintaining a generally convex growth surface of SiC crystals, adjusting differences in front-side to back-side thermal profiles of growing SiC crystals, supplying sufficient source flux to allow commercially viable growth rates for SiC crystals, and reducing the inclusion of contaminants or non-SiC particles in SiC source materials and corresponding SiC crystals. By forming larger dimension SiC crystals that exhibit lower crystallographic stress, overall dislocation densities that are associated with missing or additional planes of atoms may be reduced, thereby improving crystal quality and usable SiC crystal growth heights.
    Type: Application
    Filed: December 15, 2020
    Publication date: June 16, 2022
    Inventors: Yuri Khlebnikov, Varad R. Sakhalkar, Caleb A. Kent, Valeri F. Tsvetkov, Michael J. Paisley, Oleksandr Kramarenko, Matthew David Conrad, Eugene Deyneka, Steven Griffiths, Simon Bubel, Adrian R. Powell, Robert Tyler Leonard, Elif Balkas, Curt Progl, Michael Fusco, Alexander Shveyd, Kathy Doverspike, Lukas Nattermann
  • Publication number: 20210230769
    Abstract: Silicon carbide (SiC) wafers, SiC boules, and related methods are disclosed that provide improved dislocation distributions. SiC boules are provided that demonstrate reduced dislocation densities and improved dislocation uniformity across longer boule lengths. Corresponding SiC wafers include reduced total dislocation density (TDD) values and improved TDD radial uniformity. Growth conditions for SiC crystalline materials include providing source materials in oversaturated quantities where amounts of the source materials present during growth are significantly higher than what would typically be required. Such SiC crystalline materials and related methods are suitable for providing large diameter SiC boules and corresponding SiC wafers with improved crystalline quality.
    Type: Application
    Filed: January 29, 2020
    Publication date: July 29, 2021
    Inventors: Yuri Khlebnikov, Robert T. Leonard, Elif Balkas, Steven Griffiths, Valeri Tsvetkov, Michael Paisley
  • Publication number: 20210198804
    Abstract: Silicon carbide (SiC) wafers and related methods are disclosed that include large diameter SiC wafers with wafer shape characteristics suitable for semiconductor manufacturing. Large diameter SiC wafers are disclosed that have reduced deformation related to stress and strain effects associated with forming such SiC wafers. As described herein, wafer shape and flatness characteristics may be improved by reducing crystallographic stress profiles during growth of SiC crystal boules or ingots. Wafer shape and flatness characteristics may also be improved after individual SiC wafers have been separated from corresponding SiC crystal boules. In this regard, SiC wafers and related methods are disclosed that include large diameter SiC wafers with suitable crystal quality and wafer shape characteristics including low values for wafer bow, warp, and thickness variation.
    Type: Application
    Filed: December 17, 2020
    Publication date: July 1, 2021
    Inventors: Yuri Khlebnikov, Varad R. Sakhalkar, Caleb A. Kent, Valeri F. Tsvetkov, Michael J. Paisley, Oleksandr Kramarenko, Matthew David Conrad, Eugene Deyneka, Steven Griffiths, Simon Bubel, Adrian R. Powell, Robert Tyler Leonard, Elif Balkas, Jeffrey C. Seaman
  • Publication number: 20200069884
    Abstract: An automatic injection device including a housing, a chamber with a first compartment and a second compartment, and a seal structure between the compartments. The seal structure is initially in a sealing condition that seals the first compartment from the second compartment, where the seal includes a plug and an outer sealing member. The plug is slidably movable within the outer sealing member to convert the seal structure from the sealing condition to a mixing condition by opening a path between the first compartment and the second compartment. The automatic injection device also includes a needle assembly and an activation assembly. Activation of the activation assembly causes (1) pressurization of the first compartment, (2) the seal structure to convert from the sealing condition to the mixing condition, and (3) the first and second medicament components to be mixed and forced through the needle assembly.
    Type: Application
    Filed: November 4, 2019
    Publication date: March 5, 2020
    Inventors: Steven Griffiths, Robert L. Hill
  • Publication number: 20180256824
    Abstract: An automatic injection device including a housing, a chamber with a first compartment and a second compartment, and a seal structure between the compartments. The seal structure is initially in a sealing condition that seals the first compartment from the second compartment, where the seal includes a plug and an outer sealing member. The plug is slidably movable within the outer sealing member to convert the seal structure from the sealing condition to a mixing condition by opening a path between the first compartment and the second compartment. The automatic injection device also includes a needle assembly and an activation assembly. Activation of the activation assembly causes (1) pressurization of the first compartment, (2) the seal structure to convert from the sealing condition to the mixing condition, and (3) the first and second medicament components to be mixed and forced through the needle assembly.
    Type: Application
    Filed: November 27, 2017
    Publication date: September 13, 2018
    Inventors: Steven Griffiths, Robert L. Hill
  • Publication number: 20160250419
    Abstract: An automatic injection device including a housing, a chamber with a first compartment and a second compartment, and a seal structure between the compartments. The seal structure is initially in a sealing condition that seals the first compartment from the second compartment, where the seal includes a plug and an outer sealing member. The plug is slidably movable within the outer sealing member to convert the seal structure from the sealing condition to a mixing condition by opening a path between the first compartment and the second compartment. The automatic injection device also includes a needle assembly and an activation assembly. Activation of the activation assembly causes (1) pressurization of the first compartment, (2) the seal structure to convert from the sealing condition to the mixing condition, and (3) the first and second medicament components to be mixed and forced through the needle assembly.
    Type: Application
    Filed: May 5, 2016
    Publication date: September 1, 2016
    Inventors: Steven Griffiths, Robert L. Hill
  • Publication number: 20150283327
    Abstract: An automatic injection device including a housing, a chamber with a first compartment and a second compartment, and a seal structure between the compartments. The seal structure is initially in a sealing condition that seals the first compartment from the second compartment, where the seal includes a plug and an outer sealing member. The plug is slidably movable within the outer sealing member to convert the seal structure from the sealing condition to a mixing condition by opening a path between the first compartment and the second compartment. The automatic injection device also includes a needle assembly and an activation assembly. Activation of the activation assembly causes (1) pressurization of the first compartment, (2) the seal structure to convert from the sealing condition to the mixing condition, and (3) the first and second medicament components to be mixed and forced through the needle assembly.
    Type: Application
    Filed: June 18, 2015
    Publication date: October 8, 2015
    Inventors: Steven Griffiths, Robert L. Hill
  • Publication number: 20150018761
    Abstract: An automatic injection device including a housing, a chamber with a first compartment and a second compartment, and a seal structure between the compartments. The seal structure is initially in a sealing condition that seals the first compartment from the second compartment, where the seal includes a plug and an outer sealing member. The plug is slidably movable within the outer sealing member to convert the seal structure from the sealing condition to a mixing condition by opening a path between the first compartment and the second compartment. The automatic injection device also includes a needle assembly and an activation assembly. Activation of the activation assembly causes (1) pressurization of the first compartment, (2) the seal structure to convert from the sealing condition to the mixing condition, and (3) the first and second medicament components to be mixed and forced through the needle assembly.
    Type: Application
    Filed: July 11, 2013
    Publication date: January 15, 2015
    Inventors: Steven Griffiths, Robert L. Hill
  • Publication number: 20120071630
    Abstract: The present invention provides the use of nucleic acid sequences and/or amino acid sequences in the preparation of a vaccine for the protection of fish against infectious salmon anaemia virus. Specifically, such vaccines contain at least one nucleic acid sequence which is derived from ISAV or synthetically prepared analogues thereof, or substantially homologous sequences. These nucleic acid sequences are transcripted and translated into peptide sequences which are incorporated into a vaccination strategy to induce and immune response to the surface antigens of ISAV and therefore ISAV itself. Therefore both the use of a vaccine against ISAV, and the incorporation of peptide sequences is herein described.
    Type: Application
    Filed: August 12, 2011
    Publication date: March 22, 2012
    Applicants: OTTAWA HEALTH RESEARCH INSTITUTE, NOVARTIS AG
    Inventors: STEVEN GRIFFITHS, RACHAEL JAME RITCHIE, JOEL HEPPELL
  • Patent number: 7998484
    Abstract: The present invention provides the use of nucleic acid sequences and/or amino acid sequences in the preparation of a vaccine for the protection of fish against infectious salmon anemia virus. Specifically, such vaccines contain at least one nucleic acid sequence which is derived from ISAV or synthetically prepared analogues thereof, or substantially homologous sequences. These nucleic acid sequences are transcripted and translated into peptide sequences which are incorporated into a vaccination strategy to induce and immune response to the surface antigens of ISAV and therefore ISAV itself. Therefore both the use of a vaccine against ISAV, and the incorporation of peptide sequences is herein described.
    Type: Grant
    Filed: November 24, 2009
    Date of Patent: August 16, 2011
    Assignees: Novartis AG, Ottawa Health Research Institute
    Inventors: Steven Griffiths, Rachael Jane Ritchie, Joel Heppell
  • Publication number: 20100136038
    Abstract: The present invention provides the use of nucleic acid sequences and/or amino acid sequences in the preparation of a vaccine for the protection of fish against infectious salmon anaemia virus. Specifically, such vaccines contain at least one nucleic acid sequence which is derived from ISAV or synthetically prepared analogues thereof, or substantially homologous sequences. These nucleic acid sequences are transcripted and translated into peptide sequences which are incorporated into a vaccination strategy to induce and immune response to the surface antigens of ISAV and therefore ISAV itself. Therefore both the use of a vaccine against ISAV, and the incorporation of peptide sequences is herein described.
    Type: Application
    Filed: November 24, 2009
    Publication date: June 3, 2010
    Inventors: Steven Griffiths, Rachael Jane Ritchie, Joel Heppell
  • Patent number: 7556614
    Abstract: A separation assembly for initially keeping a first component separate from a second component includes a generally cylindrical body slidably supported within a container between the first and second components. The body includes a seal structure having an inner seal member that initially seals the first component from the second component. In response to a predetermined operating condition, the inner seal member allows the first component to flow through at least one flow path in the seal structure to mix with the second component. The body further includes a flow distributing member disposed adjacent the seal structure to evenly distribute the first component into the second component. The seal structure and the flow distributing member form a single unit.
    Type: Grant
    Filed: September 3, 2003
    Date of Patent: July 7, 2009
    Assignee: Meridian Medical Technologies, Inc.
    Inventors: Steven Griffiths, Robert L. Hill, John G. Wilmot
  • Publication number: 20080077083
    Abstract: An automatic injector separately stores liquid and dry components in respective compartments. When the injector is activated, a fluid-directing member between the liquid and dry compartments causes the liquid component to form a vortex as the liquid flows into the dry compartment. This allows the two components to combine more thoroughly and quickly to form a liquid solution that is delivered to an injection site.
    Type: Application
    Filed: August 29, 2007
    Publication date: March 27, 2008
    Inventors: Steven Griffiths, Robert Hill, Matthew Robben
  • Publication number: 20070142768
    Abstract: An automatic medicament injector having a compartment for a dry medicament component and a compartment for a wet medicament component. The two compartments are separated by a seal structure that converts from a sealing condition into a mixing condition when the device is activated. The seal structure includes a wiper that scrapes the interior walls in the dry component compartment to prevent the dry component from accumulating at the seal/glass interface. A tapered insert funnels the mixed medicament components to an attached needle assembly, but can be removed when the device is filled. A filter is provided between the medicament compartments and the needle assembly. A chamber between the filter and the needle allows for better flow through the filter. An actuation assembly drives the seal structure into the mixing condition and forces the mixed medicament through the needle and into the user.
    Type: Application
    Filed: January 26, 2007
    Publication date: June 21, 2007
    Inventors: Steven Griffiths, Robert Hill
  • Publication number: 20070142769
    Abstract: An automatic medicament injector having a compartment for a dry medicament component and a compartment for a wet medicament component. The two compartments are separated by a seal structure that converts from a sealing condition to a mixing condition when the device is activated. The seal structure includes a wiper that scrapes the interior walls in the dry component compartment to prevent the dry component from accumulating at the seal/glass interface. A tapered insert funnels the mixed medicament components to an attached needle assembly, but can be removed when the device is filled. A filter is provided between the medicament compartments and the needle assembly. A chamber between the filter and the needle allows for better flow through the filter. An actuation assembly drives the seal structure into the mixing condition and forces the mixed medicament through the needle and into the user.
    Type: Application
    Filed: January 26, 2007
    Publication date: June 21, 2007
    Inventors: Steven Griffiths, Robert Hill