Transient global modeling for the pulling process of Czochralski silicon crystal growth. II. Investigation on segregation of oxygen and carbon

We conducted the transient global simulations for the crystal pulling process of Czochralski silicon (CZ-Si) growth with the cusp-shaped magnetic field (CMF). The generation, transport, and segregation of oxygen (O) were considered for the crystal growing process. Further, the incorporation, accumulation, and segregation of carbon (C) were also predicted based on our previous studies on CZ-Si growth. The distributions of O and C at the growth interface were dynamically predicted for the diameter pulling stages, and their segregations were plotted as a function of solidified fraction and crystal length. The O level and uniformities at the growth interface exhibit a strong correlation with the depth of melt in the crucible and the flow structures inside the melt. The comparisons of different CMFs indicated that adjustments of the zero-Gauss plane (ZGP) have the potential to optimize the O segregation into the pulling crystal from the level, axial, and radial uniformities. Further, the C concentration increased with the increase in the crystal length because of the continuous contamination and the lower segregation coefficient. Hence, the developed dynamic global model also has applications in the segregation prediction of other dopants and impurities in the CZ-Si growing process.