| 摘要 |
1,191,166. Floating zone-melting. SIEMENS A.G. 22 Sept., 1967 [24 Sept., 1966], No. 43362/67. Heading BIS. A rod of silicon is zone-melted by the successive passage of an annular and a complete molten zone. The annular molten zone has a depth of one-fifth to two-thirds of the radius of the rod. The two molten zones may be passed separately in the same or opposite directions or simultaneously in the same direction at a distance apart of 4-7 cm. The complete molten zone may pass upwards or downwards. As shown, an incandescent zone is passed from a carbon element 11 to a seed 13, whereafter an annular molten zone 17 followed by a complete molten zone 18 is passed from the seed in the opposite direction by means of surrounding induction coils 16 and 15. In a modification, coil 15 is dispensed with and the power to coil 16 is increased after the complete passage of the annular molten zone to form the complete molten zone. In another embodiment (Figs. 2 and 3), the annular molten zone is formed by rotating the rod and heating by means of an induction loop situated at one side of the rod. |
