Crucible of fused vitreous silica

摘要

A crucible of pure transparent silica glass or pure translucent or opaque silica glass for the production of monocrystals used in making semiconductor elements which includes a hollow cylindrical part and a welded-on head. The head end of the hollow cylindrical part is formed from a tube with a head margin portion constricted towards the tube axis which is formed by shaping one end of the tube. A plate is welded into the aperture formed by the constricted head margin portion and has an area equal to at least one-tenth and at most four-fifths of the total head area made up by the head margin portion and the head.