Single crystal pulling apparatus

Abstract

To impart flexibility suitable for recovery of a quartz crucible to a divided type graphite crucible and avoid damage to the quartz crucible due to the flexibility. A graphite crucible 10 is divided into two or more parts by radial dividing lines 14. An opening 11a is provided in a center of a bottom of the graphite crucible 10. A protrusion 21 fitting into the opening 11a is provided on a crucible placing surface of a crucible tray 20. An inner diameter d2 of the opening 11a is 0.04 to 0.9 times an inner diameter d1 of a straight body portion of the graphite crucible 10. An outer diameter D2 of the crucible tray 20 is 0.5 or more times an outer diameter D1 of the straight body portion of the graphite crucible 10. Minimum thickness of the crucible tray 20 is 15 mm or more.

Dependencies are inferred from the claim text.