Apparatus for drawing single crystals

摘要

A crucible is mounted on a crucible support bolt (11, 34) in a vacuum chamber (33) resting on a base stand (32) and can be heated by the thermal radiation of a heating element. A drawing element (35) is provided above the melt, by means of which the crystal can be drawn up from the surface of the melt into a transfer lock chamber (36), which can be pivoted laterally with respect to the base stand (32). A separating device is provided between the crystal and the drawing element (35) to separate the crystal from the drawing element (35). The base stand (32) is formed by a platform (38) supported by four posts (37) three additional legs (39) of equal length extend upward from three of the four corners of the rectangular platform (38) holding the vacuum chamber (33), these (39) being held together at their top ends by a horizontal frame (40), which forms a right triangle. The surface projected by this frame (40) onto the platform (38) encloses approximately half of the surface of the platform, and a boom or pivot arm (41) is mounted on at least one of the legs (39), for pivoting the transfer lock chamber (36) from a position above the crucible.