| 摘要: | 連續柴氏長晶法（Continuous Czochralski crystal growth, CCz）是在傳統柴氏長晶法（Czochralski crystal growth, Cz）的基礎上進行改良，以提升生產效率。CCz 方法透過持續向坩堝中加入多晶矽，使熔湯保持穩定液面高度及化學組成。然而，為避免尚未完全熔化的多晶矽影響晶體生長，本研究引入石英隔板以隔離進料區與晶體生長區，但隔板的加入同時改變了熔湯流動與熱傳分布，並可能引起氧雜質濃度增加。因此，本研究針對連續柴氏雙坩堝長晶中的氧濃度問題，透過設計爐體結構，並使用數值模擬進行分析在不同洞口位置及尺寸、不同上隔板位置、不同側加熱器長度、不同功率比及不同晶體旋轉速度下，對溫場、流場、氧濃度以及固液(晶體-熔湯)界面高度的影響。爐體結構設計優化後可以使固液(晶體-熔湯)界面的氧濃度比原先的爐體結構降低約3.4 ppma。在反向、同向旋轉下，觀察對溫場、流場、氧濃度、固液(晶體-熔湯)界面高度及熱應力的變化。;The Continuous Czochralski (CCz) method is an enhancement of the conventional Czochralski (Cz) process, developed to improve production efficiency. In CCz, polycrystalline silicon is continuously added into the crucible to maintain a stable melt level and chemical composition. To prevent incompletely melted polycrystalline silicon from affecting crystal growth, a quartz partition is introduced to separate the feed zone from the growth region. However, the presence of the partition alters melt flow and heat transfer, potentially increasing oxygen concentration.
This study investigates the oxygen concentration in a continuous Czochralski double-crucible system through furnace design optimization and numerical simulation. The effects of partition hole location and size, upper partition position, side heater length, heater power ratio, and crystal rotation rate on temperature distribution, flow pattern, oxygen concentration, and the solid–liquid (crystal–melt) interface height were analyzed. Optimization of the furnace structure resulted in a reduction of approximately 3.4 ppma in oxygen concentration at the solid–liquid interface compared to the original design. Additionally, the impacts of counter-rotation and co-rotation on temperature, flow, oxygen distribution, interface height, and thermal stress were examined. |
