| 摘要 |
953,538. Crystal pulling. PHILIPS ELECTRICAL INDUSTRIES Ltd. May 2, 1960 [May 5, 1959], No. 15348/60. Heading BIS. A monocrystalline rod is pulled from a relatively shallow portion of a melt, in a crucible, above a cylindrical projection having a flat upper surface. The rod may be rotated during pulling. The diameter of the crucible may be at least twice that of the projection. The distance of the upper surface of the projection from the bottom of the crucible may be at least one-third of the diameter of the projection. The surface of the melt may be up to 6 mm. above the upper surface of the projection. As shown in Fig. 1, a rod 12 is pulled from the portion of a rod 11 above a graphite disc 4 supported by a shaft 5 which is lowered, as pulling proceeds, through the base of a graphite crucible 8 heated by an induction coil 7. As shown in Fig. 2, rod is pulled from melt above a stationary projection 22, melt being supplied to the crucible from a piston-operated chamber 31 via a duct 32 which passes through the centre of two superimposed air-filled annular chambers 27 and 28. |
