在本研究使用數值模擬研究了在柴氏長晶法(Czochralski crystal growth，Cz)的過程中，爐體內的不同結構設計對熔湯內的熱場、流場和氧傳輸的影響，並在模擬中加入尖點形磁場。研究結果顯示，加大坩堝尺寸可以加大熔湯自由表面的面積並增加氧雜質的蒸發量，還可以降低熔湯和坩堝壁的接觸面積，進而減少氧雜質的析出。接著，透過縮短側加熱器長度，使得側加熱器的熱集中點遠離坩堝底部，因此坩堝底部的溫度降低，進而減少從坩堝壁底部析出的氧雜質，此區域也是晶體內氧雜質的主要來源。最後，透過在側加熱器下方加入L形絕緣層，此絕緣層可以避免熱散失，加強爐體的保溫效果，同時也可以解決熔湯中心底部發生過冷的問題，並且降低晶體內的熱應力和點缺陷，進而提升晶體品質。爐體結構設計優化後可以使晶體/熔湯界面的氧濃度比原先的爐體結構降低約6.6 ppma，且加熱器的功率也可以減少了約10.3%的能耗，而晶體中心的界面高度可以減少約6.3 mm。;This study uses a numerical simulation method to study the effects of different furnace structural designs on the thermal field, flow field and oxygen transport in the silicon melt during the Czochralski crystal growth process of a cusp-shaped magnetic field. The results showed that increasing the crucible size can enlarge the area of the free melt surface and increase the evaporation of oxygen impurities. It can also reduce the contact area between the silicon melt and the crucible wall, thereby decreasing the dissolution of oxygen impurities. Furthermore, by shortening the length of the side heater, the concentration point of heat from the side heater is moved far away from the bottom of the crucible, resulting in a decrease in temperature at the bottom crucible. Therefore, it reduces the oxygen impurities dissolved from the bottom crucible wall, which region serves as the primary source of oxygen impurities within the crystal. Finally, by adding the L-shaped insulation below the side heater, heat loss is prevented, thereby strengthening the insulation effect of the furnace. This also solves the problem of overcooling at the bottom of the silicon melt center and reduces thermal stress and point defects within the crystal, thereby improving crystal quality. Optimizing the furnace structure can reduce the oxygen concentration at the crystal/melt interface by approximately 6.6 ppma compared to the original furnace structure. Moreover, the power consumption of the heater can be reduced by approximately 10.3%, and the interface height at the center of the crystal can be decreased by about 6.3 mm.
