Patents by Inventor Timothy Grotjohn

Timothy Grotjohn 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: 20130153931
    Abstract: The disclosure relates to the formation of n-doped single crystal diamond (SCD). In general, a SCD substrate is preferentially anisotropically etched to provide one or more recesses in the SCD substrate, where the recesses are defined by (1 1 1) surface sidewalls resulting from the preferential anisotropic etching process. The recesses generally have a pyramidal shape. N-type doped SCD (e.g., using a phosphorous dopant) is then deposited into the preferentially anisotropically etched recesses. When the SCD substrate is a p-type diamond (e.g., using a boron dopant), the resulting structure can be used as a p-n junction, for example for use in various power electronic apparatus such as diodes, etc.
    Type: Application
    Filed: August 31, 2011
    Publication date: June 20, 2013
    Applicant: Board of Trustees of Michigan State University
    Inventors: Timothy A. Grotjohn, Jes Asmussen, Timothy Hogan
  • Patent number: 8316797
    Abstract: New and improved microwave plasma assisted reactors, for example chemical vapor deposition (MPCVD) reactors, are disclosed. The disclosed microwave plasma assisted reactors operate at pressures ranging from about 10 Torr to about 760 Torr. The disclosed microwave plasma assisted reactors include a movable lower sliding short and/or a reduced diameter conductive stage in a coaxial cavity of a plasma chamber. For a particular application, the lower sliding short position and/or the conductive stage diameter can be variably selected such that, relative to conventional reactors, the reactors can be tuned to operate over larger substrate areas, operate at higher pressures, and discharge absorbed power densities with increased diamond synthesis rates (carats per hour) and increased deposition uniformity.
    Type: Grant
    Filed: June 16, 2009
    Date of Patent: November 27, 2012
    Assignee: Board of Trustees of Michigan State University Fraunhofer USA
    Inventors: Jes Asmussen, Timothy Grotjohn, Donnie K. Reinhard, Thomas Schuelke, M. Kagan Yaran, Kadek W. Hemawan, Michael Becker, David King, Yajun Gu, Jing Lu
  • Publication number: 20120047950
    Abstract: The disclosure relates to the inclusion of an image embedded in or on a single crystal diamond such that the image is part of the single crystal diamond structure. The disclosed methods use a combination of gemstone deposition processes and patterning processes to create single crystal gemstones with embedded color variations that can create externally visible two-dimensional or three-dimensional images in a seamless single crystal matrix without visible internal lines/interfacial boundaries. The image embedded image is differently colored from the surrounding diamond matrix. The color variation is accomplished by a change in the diamond growth conditions or treatment of the diamond.
    Type: Application
    Filed: August 23, 2011
    Publication date: March 1, 2012
    Applicant: BOARD OF TRUSTEES OF MICHIGAN STATE UNIVERSITY
    Inventors: Timothy A. Grotjohn, Carolyn Randall
  • Publication number: 20100034984
    Abstract: New and improved microwave plasma assisted reactors, for example chemical vapor deposition (MPCVD) reactors, are disclosed. The disclosed microwave plasma assisted reactors operate at pressures ranging from about 10 Torr to about 760 Torr. The disclosed microwave plasma assisted reactors include a movable lower sliding short and/or a reduced diameter conductive stage in a coaxial cavity of a plasma chamber. For a particular application, the lower sliding short position and/or the conductive stage diameter can be variably selected such that, relative to conventional reactors, the reactors can be tuned to operate over larger substrate areas, operate at higher pressures, and discharge absorbed power densities with increased diamond synthesis rates (carats per hour) and increased deposition uniformity.
    Type: Application
    Filed: June 16, 2009
    Publication date: February 11, 2010
    Applicants: Board of Trustees of Michigan State University, Fraunhofer USA
    Inventors: Jes Asmussen, Timothy Grotjohn, Donnie K. Reinhard, Thomas Schuelke, M. Kagan Yaran, Kadek W. Hemawan, Michael Becker, David King, Yajun Gu, Jing Lu
  • Publication number: 20090239078
    Abstract: The present invention relates to a microwave plasma deposition process and apparatus for producing diamond, preferably as single crystal diamond (SCD). The process and apparatus enables the production of multiple layers of the diamond by the use of an extending device to increase the length and the volume of a recess in a holder containing a SCD substrate as layers of diamond are deposited. The diamond is used for abrasives, cutting tools, gems, electronic substrates, heat sinks, electrochemical electrodes, windows for high power radiation and electron beams, and detectors.
    Type: Application
    Filed: March 10, 2009
    Publication date: September 24, 2009
    Applicants: Board of Trustees of Michigan State University, Fraunhofer USA
    Inventors: Jes Asmussen, Timothy Grotjohn, Donnie Reinhard, Rahul Ramamurti, M. Kagan Yaran, Thomas Schuelke, Michael Becker, David King
  • Patent number: 7442271
    Abstract: A miniature microwave plasma torch apparatus (10) is described. The microwave plasma torch apparatus (10) is used for a variety of applications where rapid heating of a small amount of material is needed. The miniature microwave plasma torch apparatus (10) operates near or at atmospheric pressure for use in materials processing. The apparatus (10) provides a wide range of flow rates so that discharge properties vary from diffusional flow of radicals for gentle surface processing to high velocity, approaching supersonic, torch discharges for cutting and welding applications. The miniature microwave plasma torch apparatus (10) also has a very small materials processing spot size.
    Type: Grant
    Filed: April 6, 2005
    Date of Patent: October 28, 2008
    Assignee: Board of Trustees of Michigan State University
    Inventors: Jes Asmussen, Timothy Grotjohn, Shengxi Zuo, Kadek W. Hemawan
  • Patent number: 7262408
    Abstract: An apparatus and process for manufacturing changes of a substrate in a work region which is 100×100×100 microns or smaller is described. The apparatus uses a plasma source adjacent to the work region to produce radiation or matter which changes the surface. An atomic force microscope or laser can be used in addition. The process and apparatus can be used to produce MEMS devices on a substrate for use in a wide variety of applications.
    Type: Grant
    Filed: June 14, 2006
    Date of Patent: August 28, 2007
    Assignee: Board of Trustees of Michigan State University
    Inventors: Jes Asmussen, Timothy Grotjohn, Ning Xi, Timothy P. Hogan
  • Publication number: 20060284118
    Abstract: An apparatus and process for manufacturing changes of a substrate in a work region which is 100×100×100 microns or smaller is described. The apparatus uses a plasma source adjacent to the work region to produce radiation or matter which changes the surface. An atomic force microscope or laser can be used in addition. The process and apparatus can be used to produce MEMS devices on a substrate for use in a wide variety of applications.
    Type: Application
    Filed: June 14, 2006
    Publication date: December 21, 2006
    Applicant: Board of Trustees of Michigan State University
    Inventors: Jes Asmussen, Timothy Grotjohn, Ning Xi, Timothy Hogan
  • Patent number: 7147810
    Abstract: Wetted thin diamond films which are drapable are described. The films are mounted on various substrates and used as windows for electromagnetic radiation or form a surface coating on an article of manufacture.
    Type: Grant
    Filed: October 31, 2003
    Date of Patent: December 12, 2006
    Assignees: Fraunhofer USA, Inc., Board of Trustees of Michigan State University
    Inventors: Donnie K. Reinhard, Jes Asmussen, Michael F. Becker, Timothy A. Grotjohn, Thomas Schuelke, Roger Booth
  • Publication number: 20050223992
    Abstract: A miniature microwave plasma torch apparatus (10) is described. The microwave plasma torch apparatus (10) is used for a variety of applications where rapid heating of a small amount of material is needed. The miniature microwave plasma torch apparatus (10) operates near or at atmospheric pressure for use in materials processing. The apparatus (10) provides a wide range of flow rates so that discharge properties vary from diffusional flow of radicals for gentle surface processing to high velocity, approaching supersonic, torch discharges for cutting and welding applications. The miniature microwave plasma torch apparatus (10) also has a very small materials processing spot size.
    Type: Application
    Filed: April 6, 2005
    Publication date: October 13, 2005
    Applicant: Board of Trustees of MICHIGAN STATE UNIVERSITY
    Inventors: Jes Asmussen, Timothy Grotjohn, Shengxi Zuo, Kadek Hemawan
  • Patent number: 6890300
    Abstract: A MEMS chip sensor (10, 20, 30, 40, 50, 60, 70) based upon detection of an induced inductance in the sensor is described. The sensor is used in an environment for detection of fluid pressures. The method and system is particularly used in animals, including humans, to sense pressure changes, particularly pressure in the eyeball.
    Type: Grant
    Filed: August 26, 2003
    Date of Patent: May 10, 2005
    Assignee: Board of Trustees of Michigan State University
    Inventors: John R. Lloyd, Timothy A. Grotjohn, Arthur J. Weber, Frank R. Rosenbaum, Gregory A. Goodall
  • Publication number: 20050095429
    Abstract: Wetted thin diamond films which are drapable are described. The films are mounted on various substrates and used as windows for electromagnetic radiation or form a surface coating on an article of manufacture.
    Type: Application
    Filed: October 31, 2003
    Publication date: May 5, 2005
    Applicants: Board of Trustees of Michigan State University, Fraunhofer USA, Inc.
    Inventors: Donnie Reinhard, Jes Asmussen, Michael Becker, Timothy Grotjohn, Thomas Schuelke, Roger Booth
  • Patent number: 6759808
    Abstract: An apparatus and method which maintains plasma discharges (for instance 25) in containers (for instance 20) which have an internal section of 1 cm or less in width are described. The very small cross-section plasma discharges are useful in MEMS devices, in spectrometers and in spectroscopy.
    Type: Grant
    Filed: October 25, 2002
    Date of Patent: July 6, 2004
    Assignee: Board of Trustees of Michigan State University
    Inventors: Timothy A. Grotjohn, Jes Asmussen, Andy Wijaya
  • Publication number: 20040073137
    Abstract: A MEMS chip sensor (10, 20, 30, 40, 50, 60, 70) based upon detection of an induced inductance in the sensor is described. The sensor is used in an environment for detection of fluid pressures. The method and system is particularly used in animals, including humans, to sense pressure changes, particularly pressure in the eyeball.
    Type: Application
    Filed: August 26, 2003
    Publication date: April 15, 2004
    Applicant: Board of Trustees of Michigan State University
    Inventors: John R. Lloyd, Timothy A. Grotjohn, Arthur J. Weber, Frank Rosenbaum, Gregory A. Goodall
  • Publication number: 20030080685
    Abstract: An apparatus and method which maintains plasma discharges (for instance 25) in containers (for instance 20) which have an internal section of 1 cm or less in width are described. The very small cross-section plasma discharges are useful in MEMS devices, in spectrometers and in spectroscopy.
    Type: Application
    Filed: October 25, 2002
    Publication date: May 1, 2003
    Applicant: Board of Trustees of Michigan State University
    Inventors: Timothy A. Grotjohn, Jes Asmussen, Andy Wijaya