Patents by Inventor Kill Sung Lee

Kill Sung Lee 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).

  • Slurry composition for secondary polishing of silicon wafer
    Patent number: 7534277
    Abstract: Disclosed is a slurry composition for secondary polishing of silicon wafers comprising: 2˜10 weight % of colloidal silica having an average particle size of 30˜80 nm; 0.5˜1.5 % by weight of ammonia; 0.2˜1 weight % of a hydroxyalkycellulose-based polymer for modifying rheology of the composition; 0.03˜0.5 weight % of a polyoxyethylenealkylamine ether-based nonionic surfactant; 0.01˜1 weight % of a quaternary ammonium base and the balance of deionized water.
    Type: Grant
    Filed: July 30, 2003
    Date of Patent: May 19, 2009
    Assignee: Cheil Industries, Inc.
    Inventors: Hyun Soo Roh, Tae Won Park, Kill Sung Lee, In Kyung Lee