| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a vitreous silica crucible suitable for repeated pulling (multi-pulling steps), in which erosion of the inner surface of the crucible during pulling is suppressed and brown rings or the like are hardly peeled. <P>SOLUTION: The vitreous silica crucible for pulling a silicon single crystal is characterized in that, relating to the concentration of OH groups included in an erosion thickness portion of the inner surface of the vitreous silica crucible, the OH group concentration in a range from a position corresponding to the liquid surface level of a silicon melt at the time of starting the pulling of a silicon single crystal to a position corresponding to the liquid surface level of a silicon melt at the time of finishing the pulling of the silicon single crystal is higher than the OH group concentration in a lower portion than the above range. Preferably, relating to the concentration of OH groups included in a transparent layer portion with 1 mm thickness from the inner surface of the crucible, the OH group concentration in a curved portion is higher than the OH group concentration in a bottom portion, and the OH concentration on a wall portion is higher than the OH concentration in the curved portion. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
