單晶矽是生產半導體元件中基板的主要材料，為了在製造過程中達到高質量且低缺陷的矽晶體，但由於缺陷在製造過程中是無可避免的，如何製造低缺陷的矽晶體是相當重要的課題。其中在柴式法(Czochralski method,Cz)生長單晶矽過程中，本質點缺陷會在固液界面不斷重組與產生，因此透過改變晶轉與拉速等變因控制長晶過程中產生的缺陷以達到較高品質的晶體。但由於製造過程中所耗費的時間以及材料成本等因素，如何找到合適的晶轉與拉速等變因相當困難，因此需要通過數值模擬觀察改變晶轉與拉速等變因對晶體內部的影響，以此找到合適的製程參數。
本研究以 CGSim 軟體模擬柴式長晶法(CZ)生長 8 吋單晶矽製程中，其中晶體高度生長至500mm，探討不同晶體旋轉及拉速下晶體內的氧濃度變化，並觀察摻氧以及摻氮對晶體內點缺陷分布的影響，藉此了解不同的操作條件對缺陷密度的影響。研究發現使用逆向晶轉的晶體內缺陷密度低於使用同向晶轉的晶體內缺陷密度，缺陷密度種類包含空缺型缺陷以及氧沉澱物；提升拉速對於空缺型密度也會跟著提升。

Monocrystalline silicon is the main material used in the production of substrates for semiconductor devices. In order to achieve high quality silicon crystals with low defects in the manufacturing process, it is important to produce silicon crystals with low defects because defects are inevitable in the manufacturing process. In the Czochralski method (Cz) of single crystal silicon growth, intrinsic point defects are continuously recombined and generated at the melt/crystal interface, so the defects generated during the crystal growth process are controlled by changing the crystal rotation and pulling rate to achieve higher quality crystals. However, due to the time and material cost involved in the fabrication process, it is difficult to find the appropriate variables of crystal rotation and pulling rate, so numerical simulations are needed to observe the effect of changing the variables of crystal rotation and pulling rate on the interior of the crystal to find the appropriate process parameters.
In this study, CGSim software was used to simulate the growth of 8-inch single-crystal silicon by the CZ crystal method (CZ), in which the crystal height was grown to 500 mm to investigate the variation of oxygen concentration in the crystal under different crystal rotation and pulling speed, and to observe the effect of doping with oxygen and nitrogen on the distribution of point defects in the crystal, so as to understand the effect of different operating conditions on the defect density. It was found that the defect density in the crystals with reverse crystal rotation was lower than that in the crystals with isotropic crystal rotation, and the types of defects included vacancy-type defects and oxygen precipitates.

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