Patents by Inventor Shengzhong Liu

Shengzhong Liu 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: 20020119592
    Abstract: A photovoltaic cell comprising a supporting substrate, a front contact layer on the substrate, a layer or layers of semiconductor material and a back contact layer comprising a metal, the back contact having areas without metal thereby permitting the passage of light through the cell.
    Type: Application
    Filed: April 25, 2002
    Publication date: August 29, 2002
    Inventors: Robert S. Oswald, Shengzhong Liu
  • Publication number: 20020011641
    Abstract: A photovoltaic cell comprising a supporting substrate, a front contact layer on the substrate, a layer or layers of semiconductor material and a back contact layer comprising a metal, the back contact having areas without metal thereby permitting the passage of light through the cell.
    Type: Application
    Filed: June 26, 2001
    Publication date: January 31, 2002
    Inventors: Robert S. Oswald, Shengzhong Liu
  • Patent number: 5964963
    Abstract: Thermal stresses normally associated with brazing are alleviated by a low temperature brazing technique of the present invention. A low-temperature brazing paste, preferably suitable to be melted at temperatures of no greater than 200.degree. C. (e.g., 100-200.degree. C.), containing nanoscale (.ltoreq.100 nanometer) size particles of gold, cadmium, copper, zinc, tin, lead, silver, silicon, chromium, cobalt, antimony, bismuth, aluminum, iron, magnesium, nitrogen, carbon, boron, and alloys and composites of these materials, is applied as a bead or as a powder spray at the junction of two components desired to be joined together. Energy from a source such as a laser beam (for example a CO.sub.2 laser, an Nd-Yag laser or an excimer laser), flame, arc, plasma, or the like, is "walked" along the brazing material. The energy beam is sufficient to cause melting and re-crystallization of the nanoscale-particle-containing brazing paste.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: October 12, 1999
    Inventors: Manuel C. Turchan, Pravin Mistry, Shengzhong Liu
  • Patent number: 5902498
    Abstract: Thermal stresses normally associated with joining are alleviated by a low temperature joining technique of the present invention. A low-temperature joining material is applied (as a paste, or as a powder spray, or as a tape, or as a paint, or as a putty) at the junction of two components desired to be joined together. Energy from a source such as a laser beam (for example an Nd:YAG or a CO.sub.2 laser) or by a flame, arc, plasma, or the like, is either "walked" along the joining material to react the entire amount of joining material, or the joining material is self-sustaining and simply requires igniting a selected portion of the joining material by the energy source. In an exemplary application of the process, vanes are brazed to the bowl and/or to the shroud of an automatic transmission bowl (impeller or turbine) assembly, preferably using the low-temperature joining material. Systems for delivering the joining material and the energy are described. The fabrication of hollow vanes is described.
    Type: Grant
    Filed: March 24, 1997
    Date of Patent: May 11, 1999
    Assignee: QQC, Inc.
    Inventors: Pravin Mistry, Shengzhong Liu, Manuel C. Turchan
  • Patent number: 5900225
    Abstract: Diamond materials are formed by sandwiching a carbon-containing material in a gap between two electrodes. A high-amperage electric current is applied between the two electrode plates so as cause rapid-heating of the carbon-containing material. The current is sufficient to cause heating of the carbon-containing material at a rate of at least approximately 5,000.degree. C./sec, and need only be applied for a fraction of a second to elevate the temperature of the carbon-containing material at least approximately 1000.degree. C. Upon terminating the current, the carbon-containing material is subjected to rapid-quenching (cooling). This may take the form of placing one or more of the electrodes in contact with a heat sink, such as a large steel table. The carbon-containing material may be rapidly-heated and rapidly-quenched (RHRQ) repeatedly (e.g., in cycles), until a diamond material is fabricated from the carbon-containing material.
    Type: Grant
    Filed: May 14, 1996
    Date of Patent: May 4, 1999
    Assignee: QQC, Inc.
    Inventors: Pravin Mistry, Shengzhong Liu
  • Patent number: 5849079
    Abstract: A method and system for manufacturing diamond film. The method involves forming a carbonaceous vapor, providing a gas stream of argon, hydrogen and hydrocarbon and combining the gas with the carbonaceous vapor, passing the combined carbonaceous vapor and gas carrier stream into a chamber, forming a plasma in the chamber causing fragmentation of the carbonaceous and deposition of a diamond film on a substrate.
    Type: Grant
    Filed: April 4, 1995
    Date of Patent: December 15, 1998
    Assignee: The University of Chicago
    Inventors: Dieter M. Gruen, Alan R. Krauss, Shengzhong Liu, Xianzheng Pan, Christopher D. Zuiker
  • Patent number: 5620512
    Abstract: A method and system for manufacturing diamond film. The method involves forming a fullerene vapor, providing a noble gas stream and combining the gas with the fullerene vapor, passing the combined fullerene vapor and noble gas carrier stream into a chamber, forming a plasma in the chamber causing fragmentation of the fullerene and deposition of a diamond film on a substrate.
    Type: Grant
    Filed: October 27, 1993
    Date of Patent: April 15, 1997
    Assignee: University of Chicago
    Inventors: Dieter M. Gruen, Shengzhong Liu, Alan R. Krauss, Xianzheng Pan
  • Patent number: 5516500
    Abstract: Diamond materials are formed by sandwiching a carbon-containing material in a gap between two electrodes. A high-amperage electric current is applied between the two electrode plates so as cause rapid-heating of the carbon-containing material. The current is sufficient to cause heating of the carbon-containing material at a rate of at least approximately 5,000.degree. C./sec, and need only be applied for a fraction of a second to elevate the temperature of the carbon-containing material at least approximately 1000.degree. C. Upon terminating the current, the carbon-containing material is subjected to rapid-quenching (cooling). This may take the form of placing one or more of the electrodes in contact with a heat sink, such as a large steel table. The carbon-containing material may be rapidly-heated and rapidly-quenched (RHRQ) repeatedly (e.g., in cycles), until a diamond material is fabricated from the carbon-containing material.
    Type: Grant
    Filed: August 9, 1994
    Date of Patent: May 14, 1996
    Assignee: QQC, Inc.
    Inventors: Shengzhong Liu, Pravin Mistry