Patent ID: 6916370
Filing Date: 2005-07-12
Classification: C03B,C30B,Y02P,Y10S,Y10T

Abstract:
1. A quartz glass crucible for pulling up silicon single crystal, said quartz glass crucible comprising a double layered structure comprising a naturally occurring quartz glass outer layer and a synthetic quartz glass inner layer, wherein said synthetic quartz glass inner layer contains at least one type of an alkali metal ion selected from the group consisting of Na ion, K ion, and Li ion diffused or moved from said naturally occurring quartz glass outer layer into said synthetic quartz glass inner layer, and wherein the quartz glass crucible has an inner surface, and, when the inner surface of said quartz glass crucible is brought into contact with a silicon melt, a crystalline layer in the inner surface is formed in the range of from 0.1 μm to 10 μm of thickness per hour of contact.