Patents Assigned to Wacker Chemitronic Gesellschaft
  • Process for preserving the surface of silicon wafers
    Patent number: 4973563
    Abstract: A process for preserving the surface of silicon wafers after the wafers are polished in a conventional polishing operation by converting the wafer surface to the hydrophobic state, in particular, by polishing, or with hydrofluoric acid and treating immediately afterwards with a reagent, e.g., alcohols, organosilanes or silanols and preferably in aqueous solution. The wafer becomes coated in this process with a protective layer which inhibits surface deterioration, and also permits long storage times.
    Type: Grant
    Filed: June 20, 1989
    Date of Patent: November 27, 1990
    Assignee: Wacker Chemitronic Gesellschaft
    Inventors: Helene Prigge, Anton Schnegg, Gerhard Brehm
  • Induction heating coil for the floating zone pulling of crystal rods
    Patent number: 4749837
    Abstract: An induction heating coil for a zone pulling of semiconductor rods assures the disturbance-free performance of the pulling process even at the high power densities required for large rod diameters (approximately 10 to 12 cm). According to the invention, the arc-over paths between surfaces in the region of the coil slot, which are at differing potentials, are covered by one or more movable planar structures of temperature-stable insulating material which are introduced into the coil slot.
    Type: Grant
    Filed: February 4, 1987
    Date of Patent: June 7, 1988
    Assignee: Wacker Chemitronic Gesellschaft
    Inventors: Wilfried von Ammon, Heinz Klinger