Crystal pulling apparatus

摘要

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.