Sheath model for radio-frequency-biased, high-density plasmas valid for all omega/omega(i)
Sheath model for radio-frequency-biased, high-density plasmas valid for all omega/omega(i)
复制标题
射频偏置、高密度等离子体的鞘模型对所有 omega/omega(i) 均有效
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
M. Sobolewski
中科院分区：
文献类型：
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作者：
M. Sobolewski
提出了一个高密度放电鞘层的模型，在频率omega与ω (i)相当的频率上施加射频（rf）偏置，ω (i)是鞘层边缘的离子等离子体频率。该模型使用流体方程处理离子动力学，包括所有与时间相关的项。将模型预测的电流、阻抗和功率与在1.33 Pa （10 mTorr）氩气高密度放电中进行的测量结果进行了比较，rf偏置频率为0.1至10 MHz (ω / ω (i)从0.006到1.8)，rf偏置电压为1至200 V。模型预测结果与测量结果非常吻合，比忽略时间依赖动力学的模型得到的结果要好得多。特别是，功率测量值与先前模型预测的功率之间高达40- 50%的差异现在得到了解释和消除。该模型还解释了为什么使用以前的鞘层模型从电测量中提取等离子体参数的方法可能会失败，并提出了更准确的提取这些参数的方法。
A model is proposed for sheaths in high-density discharges, with radio-frequency (rf) bias applied at frequencies omega comparable to omega(i), the ion plasma frequency at the edge of the sheath. The model treats ion dynamics using fluid equations, including all time-dependent terms. Model predictions for current, impedance, and power were compared to measurements performed in high-density discharges in argon at 1.33 Pa (10 mTorr) at rf bias frequencies from 0.1 to 10 MHz (omega/omega(i) from 0.006 to 1.8) and rf bias voltages from 1 to 200 V. Model predictions were in good agreement with measurements, much better than that obtained by models that neglect time-dependent ion dynamics. In particular, differences of as much as 40-50 % between power measurements and the power predicted by previous models are now explained and eliminated. The model also explains why methods of extracting plasma parameters from electrical measurements using previous sheath models may fail, and it suggests more accurate methods of extracting these parameters.