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，電漿時常在關鍵製程中佔有一席之地，而電容耦合電漿源(Capacitively coupled plasma (CCP) sources)近年來已經被普遍地使用在材料製程中，此外氬氣/氫氣電漿在半導體上是常見的蝕刻製程氣體，使用氬氣混合氫氣之電漿可有效率地移除基板表面的氧化層，然而，在蝕刻製程中之操作氣壓是更低的，在此條件下，電子能量分佈函數將會偏離模擬軟體CFD-ACE+流體模式中假設之馬克斯威爾分佈，此差異最主要會影響到電漿中活性粒子的比例，進而導致模擬出來的電漿行為表現以及欲達到之製程效果產生誤差，而採用動力模式則可以透過求解波茲曼方程式得出電子能量分佈函數，進而避免此問題，且在該模式中藉由查詢表的做法，可使模擬所需要的時間大幅下降約50 %，因此本研究以CCP為模擬結構，以動力模式對氬氣/氫氣電漿進行暫態模擬。
本研究第一部份分別使用流體與動力模式模擬氬氣電漿，不僅分析其基本放電特性與活性粒子之分佈，也驗證了模擬軟體CFD-ACE+中的動力模式。第二部份之研究建立在第一部份研究之基礎上，以動力模式模擬了氬氣/氫氣電漿，分析了電漿中主要活性粒子(H、H3+、Ar+、ArH+)的濃度分佈。而氣壓改變對放電特性以及Ar+濃度分佈的演變皆詳細地呈現並且論述。接著則是比較在0.1 Torr時以動力模式與流體模式進行模擬後的結果，並且與Vladimir I. Kolobov團隊所作的結果相互對照與討論。最後是探討活性粒子到達基板表面之通量，此參數是攸關於影響製程效果之重要指標，由結果可看出在兩種模式下之通量比例具有明顯之差異，因此，使用動力模式可增加模擬之精確度以避免在流體模式中之假設所造成之誤差。

Plasma plays a vital role in semiconductor manufacturing process nowadays. In recent years, as the size of semiconductor device shrinking, plasma engineering becomes an essential skill in some critical processes. Capacitively coupled plasma (CCP) sources was used as a simulating structure in this study which is still the most used devices for routine plasma processing because of its simplicity and the possibility to produce large plasma volumes.
In the etching process, Ar/H2 plasma has better etching rate for oxide layer than Ar plasma, however, lower pressure condition is needed in etching process, the default assumption of electron energy distribution function (EEDF) in the fluid model of Plasma Module in CFD-ACE+ is a Maxwellian distribution for the sake of convenience which is not a proper method under lower pressure condition, because the EEDF will departure from Maxwellian distribution. Some reaction rate constants and transport coefficients depend sensitively on deviations from the EEDF, such as ionization and dissociation reaction caused by electron impact in molecular gas discharge, so the ratio of the species in the plasma will be changed. To prevent from the errors caused by the assumed EEDF, it is necessary to adopt kinetic model which solves simplified Boltzmann equation to obtain the real EEDF instead of assuming Maxwellian distribution. Having the EEDF, the electron reaction rate constant and transport coefficients will be collected in the Lookup Table (LUT) which is a great method to provide sufficient accuracy and reduce the computational requirements around 50%.
In the first part of this study, the comparison and analysis of the results of fluid model and kinetic model are presented and the kinetic model is verified as well. The second part of this study is about the electron kinetic simulation of Ar/H2 plasma which was conducted under 1, 0.5 and 0.1 Torr condition. The result of EEDF exhibits expectedly that the distribution of higher energy electron becomes larger because of less energy loss during the collision with lower pressure condition. On the other hand, the discharge behaviors and the distribution of species (H、H3+、Ar+、ArH+) in Ar/H2 plasma are analyzed completely. Furthermore, the differences and comparisons of Ar/H2 plasma with kinetic and fluid model are presented, the trends of the result are consistent with the literature. According to different EEDF applied to the models, the ratios of species flux on the powered electrode surface are significantly different which will affect etching process largely.

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