In this work, Czochralski silicon crystals were grown from a limited o
xygen source crucible to determine the dominant flow of oxygen transpo
rt in silicon melt. The oxygen concentration in silicon crystal was fo
und mainly to be controlled by the upward flow below the growth interf
ace, with the crucible bottom as the dominant oxygen source. In this p
henomenon, the region under the growth interface is assumed to remain
rich in oxygen. Numerical simulation in the same system as that used i
n the experiment showed the same tendency. It also indicates that the
concentration of this region strongly depends on the free surface regi
on, whose concentration is to a large extent determined by dissolution
from the crucible corner, which is heated to the highest temperature
during crystal growth.