Method of manufacturing silica glass crucible for pulling silicon single crystals

摘要

A method of manufacturing a silica glass crucible for pulling silicon single crystals is disclosed. In the method, reduced pressure is imparted from the inner surface to the outer surface of a crucible-shaped molded product and the crucible-shaped molded product is arc-fused while rotating the same to form a silica glass crucible with a transparent layer on the inner surface side and a bubble layer on the outer surface side. The inner surface of the wall portion of the silica glass crucible is fused a second time by arc fusion to cause bubbles present in the transparent layer of the inner surface of the wall portion to be displaced toward the bottom portion of the inner surface of the wall portion. The inner surface of the bottom portion of the silica glass crucible is fused a second time by arc fusion to cause bubbles present in the transparent layer of the inner surface of the bottom portion to be displaced toward the periphery of the inner surface of the bottom portion. Either the step of displacement toward the bottom portion or the step of displacement toward the outer periphery is inverted first.