電漿在半導體製程中有很廣泛的應用，在近年先進的製程中，隨著元件尺寸逐漸縮小，電漿相關的製程也越發重要，而電感式耦合電漿源(Inductively coupled plasma source, ICP)近年來已經被普遍地使用於半導體製程中，此外三氟化氮(Nitrogen trifluoride, NF3)常被當作蝕刻氣體，其原因為NF3能夠有效的分解成氟自由基，且所有的反應產物都具揮發性，能避免汙染或在腔體內形成聚合物。在NF3中混合Ar，能夠平衡反應產生的大量負離子，並使放電更加穩定，且產生的電漿更加均勻，在半導體製程上添加更多優勢。
本研究使用商業用模擬軟體CFD-ACE+來進行模擬，使用CFD-ACE+內建資料庫，其中共考慮了二十種粒子及一百二十七條反應式，並以電感式耦合電漿源為模型腔體，建立一個二維軸對稱流體模型，模擬NF3混合Ar電漿的放電行為。
在吸收功率為1200 W，氣壓10 mTorr，NF3比例為1.25%時，電子密度約為1E16 1/m3，分解產生的氟原子附著電子，使得電子密度偏低，氟原子為最主要的自由基，在腔體表面可以得到均勻的氟原子通量，其值約為1.3E-8 kg/(m2×s)。在改變吸收功率的情況下，隨著功率吸收的上升，電子密度和電子溫度也跟著增加。當吸收功率增加，分解出更多氟原子，氟原子通量也跟著增加。本論文以1.25%、10%和30%三種不同比例的NF3電漿分析其特性，隨著NF3比例的增加，電子因附著反應而下降，氟原子通量因NF3比例而增加。在調整氣壓的情況下，當氣壓降低時，腔體內氣體較容易擴散，氟原子密度相較於高氣壓變得較均勻，到達腔體表面的氟原子通量也隨之增加。

Plasma is widely used in semiconductor manufacturing processes. In recent years, in advanced manufacturing processes, as the size of components gradually shrinks, plasma-related processes are becoming more and more important. Inductively coupled plasma source (ICP) In recent years, it has been widely used in the semiconductor manufacturing process. In addition, Nitrogen trifluoride (NF3) is often used as an etching gas. The reason is that NF3 can be effectively decomposed into fluorine radicals, and all reaction products have volatile to avoid contamination or polymer formation in the cavity. Mixing Ar in NF3 can balance the large number of negative ions generated by the reaction, make the discharge more stable, and the generated plasma more uniform, adding more advantages to the semiconductor process.
In this study, the commercial simulation software CFD-ACE+ was used to simulate, using the CFD-ACE+ built-in database, which considered a total of 20 particle and 127 reaction formulas, and used the inductively coupled plasma source as the model cavity to establish a two-dimensional axisymmetric fluid model to simulate the discharge behavior of NF3 mixed Ar plasma.
When the absorbed power is 1200 W, the pressure is 10 mTorr, the NF3 ratio is 1.25%, the electron density is about 1×1016 1/m3, and the fluorine atoms produced by decomposition attach electrons so that the electron density is low, and the fluorine atoms are the most important free radicals, and the uniform fluorine atomic flux can be obtained on the surface of the cavity, and its value is about 1.3×10-8 kg/(m2×s). In the case of changing the absorbed power, as the power absorption increases, the electron density and electron temperature also increase. When the absorption power increases, more fluorine atoms are decomposed, and the fluorine atom flux also increases. In this paper, the properties of NF3 plasma in three different ratios of 1.25%, 10%, and 30% were analyzed, and as the NF3 ratio increased, electrons decreased due to the attachment reaction, and the fluorine atomic flux increased due to the NF3 ratio. In the case of adjusting the pressure, when the pressure is reduced, the gas in the cavity is more easily diffused, the density of fluorine atoms becomes more uniform compared with the high pressure, and the flux of fluorine atoms reaching the surface of the cavity also increases.

摘要 1
Abstract 2
目錄 4
圖目錄 7
表目錄 14
第一章 緒論 15
1.1 研究背景 15
1.2 研究目的 16
第二章 文獻回顧 17
2.1 NF3電漿於半導體製程的應用 17
2.2 NF3電漿混合其他氣體之優點 23
2.3 NF3/Ar/O2 於遠距電漿源之模擬 25
2.4 文獻回顧總結 31
第三章 物理模型與研究方法 32
3.1 模擬軟體介紹 32
3.2 CFD-ACE+模擬之物理模型 33
3.3 模擬之幾何結構 38
3.4 反應式資料庫 39
3.5 邊界條件設定 51
第四章 NF3/Ar電漿放電模擬結果 53
4.1 NF3/Ar電漿放電 53
4.1.1 NF3/Ar電漿放電起始條件與參數設定 54
4.1.2 NF3/Ar電漿放電模擬結果分析 55
4.2 不同吸收功率對NF3/Ar電漿模擬結果比較 76
4.2.1 不同吸收功率對NF3/Ar電漿放電起始條件與參數設定 76
4.2.2 不同吸收功率對NF3/Ar電漿放電模擬結果分析 77
4.3 不同NF3比例對NF3/Ar電漿模擬結果比較 87
4.3.1 不同NF3比例對NF3/Ar電漿放電起始條件與參數設定 87
4.3.2 不同NF3比例對NF3/Ar電漿放電模擬結果分析 88
4.4 不同氣壓對NF3/Ar電漿模擬結果比較 102
4.4.1 不同氣壓對NF3/Ar電漿放電起始條件與參數設定 102
4.4.2 不同氣壓對NF3/Ar電漿放電模擬結果分析 103
4.5 與文獻結果之比較 120
4.6 模型改進 126
第五章 總結 128
附錄A CFD-ACE+內建資料庫Arrhenius form參數驗證 129
附錄B CFD-ACE+內建資料庫Cross section data驗證 138
附錄C 氟原子通量於腔體表面問題分析 150
附錄D 使用COMSOL模擬氬氣電漿外接射頻偏壓 154
D.1 使用COMSOL模擬氬氣電漿外接射頻偏壓參數設定 154
D.2 使用COMSOL模擬氬氣電漿外接射頻偏壓結果分析 155
參考文獻 162

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