Patent ID: 7686887

Claim:
A quartz glass crucible for pulling up single crystal silicon, said crucible comprising a crucible base body having a bottom part having a lowest side and a side wall having an upper end plane, and an inner layer provided on an inner surface thereof, wherein said inner layer comprises: a) a first part consisting of a synthetic quartz extending from the bottom part to a height of at least 0.25 H; b) a second part made of a naturally occurring quartz glass or made of mixed quartz glass of naturally occurring and synthetic quartz glass, and extending in at least a range of from 0.5 H to 0.8 H; and c) a residual part made of quartz glass selected from the group consisting of synthetic quartz glass, naturally occurring quartz glass, and mixed quartz glass of naturally occurring and synthetic quartz glass, wherein H represents a height from the lowest side of the bottom part to the upper end plane of the wall.