Numerical Investigation of Coupled Effects of Rotational Speed Difference and Growth Rate on VO _x Defect Behavior in Czochralski Silicon

Abstract This study employs numerical simulation to analyze the coupled effects of rotation speed difference (Δω) and growth rate (V g ) on thermal stress and oxygen‐related defect behavior during Czochralski silicon single crystal growth. The results indicate that increasing Δω enhances shear convection, raises the stress level at the solid–liquid interface, and promotes vacancy formation; when Δω exceeds 12 rpm, vacancy concentration increases linearly, significantly enhancing the formation of VO and VO 2 complexes. Under the same Δω increase, accelerating the crystal rotation leads to a greater rise in VO x concentration compared to accelerating the crucible. As V g increases, the S–L interface shifts upward, temperature gradients and thermal stress intensify simultaneously, and the concentrations of VO and VO 2 increase by 26.1% and 25.88%, respectively. Therefore, Δω and V g exhibit a strong synergistic regulatory effect on the thermal field and point defect evolution. Improper control may lead to excessive generation and accumulation of VO x defects, ultimately degrading crystal quality. Hence, in practical CZ crystal growth, it is essential to optimize the coordination of Δω and V g to achieve both high growth efficiency and effective defect suppression.