SINGLE CRYSTAL PRODUCTION APPARATUS

PURPOSE:To produce a high-quality single crystal in high efficiency, by encircling a single crystal pulling zone with a heat-shielding member composed of an annular rim and a specific heat-shielding member, thereby forming a proper temperature gradient along the pulling direction while keeping excellent heat-insulation effect. CONSTITUTION:An annular space having a right-angled triangle cross-section is formed by integrating an annular outer ring part 43a having L-shaped cross-section with an inner ring part 43b having an inverted conical form. A heat-insulation material 43d is closely packed in the annular space to form a heat-shielding member 43. A heat-shielding part 4 is produced by engaging the heat-shielding member 43 with an inner circumferential edge of a thick-walled annular rim part 41 provided with a supporting cylinder 42 on the lower face near the outer circumferential edge via flanges 43e, 43f and a seat 41a of the annular rim part 41. The heat-shielding part 4 is arranged around a pulling zone through which a single crystal 8 is pulled up via a pulling shaft 7 and a seed crystal 6 from a double-walled crucible 1 having a quartz vessel 1b in a graphite vessel 1a of a Czochralski single crystal production apparatus. A single crystal 8 can be grown while effectively shielding the heat radiated from the crucible 1 and the molten liquid.