| 摘要 |
A long thin rod (16) of semi-conductor material is pulled by means of a pulling device (18) through a sealing device (72) from a molten zone produced by an induction coil (12) at the top of a thick rod (8) in a tube (1). The pulling device, which is adapted to accommodate rods of various diameters, pulls the thin rod at a constant pulling speed and simultaneously rotates it and maintains it axially aligned. The sealing device (Fig. 5) comprises ten spaced discs (94) of Teflon, each having a central aperture with radial slits for passage of the thin rod. Below the discs, in a casing (10), are situated three bearing rods (74) which maintain the thin rod axially aligned while accepting rods of varying diameter. The thick rod is supported on a rotary shaft (4) which is raised as pulling proceeds. A protective gas passes upwards through the tube and escapes between the thin rod and the discs. The distance between the bearing rods and the molten zone may be 1-7. |
