You Ye-Bin, Lee Young-Seok, Kim Si-Jun, Cho Chul-Hee, Seong In-Ho, Jeong Won-Nyoung, Choi Min-Su, You Shin-Jae
Department of Physics, Chungnam National University, Daejeon 34134, Korea.
Institute of Quantum Systems (IQS), Chungnam National University, Daejeon 34134, Korea.
Nanomaterials (Basel). 2022 Oct 27;12(21):3798. doi: 10.3390/nano12213798.
One of the cleaning processes in semiconductor fabrication is the ashing process using oxygen plasma, which has been normally used N gas as additive gas to increase the ashing rate, and it is known that the ashing rate is strongly related to the concentration of oxygen radicals measured OES. However, by performing a comprehensive experiment of the O plasma ashing process in various N/O mixing ratios and RF powers, our investigation revealed that the tendency of the density measured using only OES did not exactly match the ashing rate. This problematic issue can be solved by considering the plasma parameter, such as electron density. This study can suggest a method inferring the exact maximum condition of the ashing rate based on the plasma diagnostics such as OES, Langmuir probe, and cutoff probe, which might be useful for the next-generation plasma process.
半导体制造中的清洗工艺之一是使用氧等离子体的灰化工艺，通常使用氮气作为添加气体来提高灰化速率，并且已知灰化速率与通过发射光谱法（OES）测量的氧自由基浓度密切相关。然而，通过在各种氮/氧混合比和射频功率下对氧等离子体灰化工艺进行全面实验，我们的研究表明，仅使用发射光谱法测量的密度趋势与灰化速率并不完全匹配。通过考虑诸如电子密度等等离子体参数，可以解决这个问题。本研究可以提出一种基于发射光谱法、朗缪尔探针和截止探针等等离子体诊断方法来推断灰化速率精确最大条件的方法，这可能对下一代等离子体工艺有用。
