Patents Examined by Felisa Garett
  • Crystal pulling apparatus
    Patent number: 5707447
    Abstract: A crystal pulling apparatus for producing a crystal boule (17) from a material melted in a crucible (4) has, in a tank (1), a heater (5) surrounding the crucible (4). The tank (1) has in the area of the crucible (4) an annular chamber (8) defined on the heater (5) side by an inner protective wall (6) and connected to the shielding gas outlet (14, 15), and on the outside by an outer protective wall (7) behind which the thermal insulation (10) of the tank (1) is located.
    Type: Grant
    Filed: September 26, 1996
    Date of Patent: January 13, 1998
    Assignee: Balzers und Leybold Deutschland Holding AG
    Inventors: Winfried Schulmann, Johann Scholler