SF₆/O₂ plasma discharge has extensive applications in semi-conductor industry for anisotropic etching of silicon. Herein, a self-consistent fluid model has been used to investigate the capacitive coupled SF₆/O₂ plasma discharge. A complete set of reactions in gas phase which include electron impact reactions, ion-ion reactions, neutral–neutral reactions and charge transfer reactions in tandem with the primary processes such as dissociation excitation, and ionization were incorporated in the model. The densities of dominant plasma species (both neutral and charged) were calculated. Furthermore, the impact of O₂ concentration on the plasma characteristics was studied. The results showed a bell shape distribution for neutral species while uniform distribution for charged species at center of the discharge. Moreover, it was demonstrated that the dominant etching species in the discharge were F, O, S, SF₅⁺, FO, F⁺, O⁺, O₂⁺ and S⁺. With the increase of O₂ concentration in the plasma, there is a decrease in the ratio of neutral species (i.e., F/ O) and overall etch rate, signifying that chemical etching is the prominent process for the discharge. In conclusion, the anisotropic etching of Si substrate can be efficiently achieved using the optimum input parameters for SF₆/O₂plasma discharge.

SF ₆ / O ₂等离子放电在半导体工业中用于硅的各向异性刻蚀具有广泛的应用。在本文中，自洽流体模型已用于研究电容耦合SF ₆ / O ₂等离子体放电。该模型包括一整套气相反应，包括电子撞击反应，离子反应，中性-中性反应和电荷转移反应，以及诸如离解激发和电离等主要过程。计算了主要血浆物质（中性和带电）的密度。此外，O ₂的影响研究了浓度对血浆特性的影响。结果表明，中性物质呈钟形分布，而放电中心带电物质呈均匀分布。此外，已证明放电中的主要蚀刻种类为F，O，S，SF ₅ ⁺，FO，F ⁺，O ⁺，O ₂ ⁺和S ⁺。随着等离子体中O ₂浓度的增加，中性物质（即F / O）的比率和总蚀刻速率降低，这表明化学蚀刻是放电的主要过程。总之，使用SF的最佳输入参数可以有效地实现Si衬底的各向异性刻蚀₆ / O ₂等离子体放电。