SILICA GLASS CRUCIBLE HAVING MULTILAYERED STRUCTURE

摘要

Disclosed is a silica glass crucible employed in pulling silicon single crystals. The crucible comprises at least a transparent layer, semitransparent layer, and opaque layer disposed from the inner surface side to the outer surface side of the crucible. The content of bubbles in the transparent layer is less than 0.3 percent; the content of bubbles in the semitransparent layer falls within a range of from 0.3 to 0.6 percent; and the content of bubbles in the opaque layer is greater than 0.6 percent.