Patents by Inventor Junmin Xue

Junmin Xue 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: 20070190363
    Abstract: Heterolayered thin films having ferroelectric/piezoelectric layers of alternating crystal structures and methods of their preparation are provided. In the ferroelectric/piezoelectric thin film, a first layer has a rhombohedral crystal structure and a second layer adjacent the first layer has a tetragonal crystal structure. The layers have a (100) preferred orientation with a-axis normal to the surface of the film. The first layer can be a Zr-rich lead ziroconate titanate layer (e.g. PbZr0.8Ti0.2O3) and the second layer can be a Ti-rich PZT layer (e.g., PbZr0.2Ti0.8O3). Heterolayered ferroelectric/piezoelectric thin film comprising a plurality of such first and second layers in alternating sequence exhibits particularly improved electrical properties.
    Type: Application
    Filed: April 23, 2007
    Publication date: August 16, 2007
    Inventors: John Wang, Anthony Zhou, Junmin Xue
  • Patent number: 7229662
    Abstract: Heterolayered thin films having ferroelectric/piezoelectric layers of alternating crystal structures and methods of their preparation are provided. In the ferroelectric/piezoelectric thin film, a first layer has a rhombohedral crystal structure and a second layer adjacent the first layer has a tetragonal crystal structure. The layers have a (100) preferred orientation with ?-axis normal to the surface of the film. The first layer can be a Zr-rich lead ziroconate titanate layer (e.g., PbZr0.8Ti0.2O3) and the second layer can be a Ti-rich PZT layer (e.g., PbZr0.2Ti0.8O3). Heterolayered ferroelectric/piezoelectric thin film comprising a plurality of such first and second layers in alternating sequence exhibits particularly improved electrical properties.
    Type: Grant
    Filed: December 16, 2003
    Date of Patent: June 12, 2007
    Assignee: National University of Singapore
    Inventors: John Wang, Anthony Zhaohui Zhou, Junmin Xue
  • Publication number: 20050128675
    Abstract: Heterolayered thin films having ferroelectric/piezoelectric layers of alternating crystal structures and methods of their preparation are provided. In the ferroelectric/piezoelectric thin film, a first layer has a rhombohedral crystal structure and a second layer adjacent the first layer has a tetragonal crystal structure. The layers have a (100) preferred orientation with ?-axis normal to the surface of the film. The first layer can be a Zr-rich lead ziroconate titanate layer (e.g., PbZr0.8Ti0.2O3) and the second layer can be a Ti-rich PZT layer (e.g., PbZr0.2Ti0.8O3). Heterolayered ferroelectric/piezoelectric thin film comprising a plurality of such first and second layers in alternating sequence exhibits particularly improved electrical properties.
    Type: Application
    Filed: December 16, 2003
    Publication date: June 16, 2005
    Inventors: John Wang, Anthony Zhou, Junmin Xue
  • Patent number: 6627104
    Abstract: Mechanochemical fabrication produces electroceramics using oxides as starting materials. The fabrication starts with mixing industrial ceramic oxide powders. Electroceramic phases are formed by reacting the oxide powders in a mechanochemical chamber, which is a wear-resistant cylindrical vial with one or more solid balls inside. The formation of electroceramic phases of pervoskite structure and fine crystallinity are activated by mechanical energy or a combination of mechanical energy and thermal energy. Sintered electroceramic materials and components are fabricated when compacts or green bodies made of the resulting ceramic powders are densified at the sintering temperature.
    Type: Grant
    Filed: March 26, 2001
    Date of Patent: September 30, 2003
    Assignee: The National University of Singapore
    Inventors: John Wang, Dongmei Wan, Junmin Xue
  • Patent number: 6592805
    Abstract: A method for producing electroceramic materials of high sintered density from hydroxide and/or oxalate precursors is disclosed. In this method the precursor(s) are compacted to form a preform, thermally treated, recompacted and then sintered to form finished products.
    Type: Grant
    Filed: June 21, 2001
    Date of Patent: July 15, 2003
    Assignee: National University of Singapore
    Inventors: John Wang, Junmin Xue, Leong Ming Gan, Ser Choon Ng, Leong Chew Lim