Patents by Inventor Joyce A. Broka

Joyce A. Broka 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).

  • Purification of carbothermally produced aluminum nitride
    Patent number: 5100846
    Abstract: A method is disclosed for purifying aluminum nitride produced by carbothermal reaction of aluminum oxide, carbon and nitrogen. Precursor pellets including aluminum oxide and carbon are exposed to nitrogen under conditions sufficient to carbothermally produce aluminum oxide, thereby producing aluminum nitride pellets having surface portions relatively rich in thermal conductivity-lowering and color-causing impurities compared to core portions of the aluminum nitride pellets. Significant amounts of the surface portions are thereafter removed to thereby significantly increase the purity of the aluminum nitride pellets.
    Type: Grant
    Filed: September 13, 1990
    Date of Patent: March 31, 1992
    Assignee: The Dow Chemical Company
    Inventors: David A. Dunn, James A. Hughes, Joyce A. Broka, Michael S. Paquette