Validity of actinometry to monitor oxygen atom concentration in microwave discharges created by surface wave in O2‐N2 mixtures
Validity of actinometry to monitor oxygen atom concentration in microwave discharges created by surface wave in O2‐N2 mixtures
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DOI：
10.1063/1.355897
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发表时间：
1994
影响因子：
3.2
通讯作者：
A. Granier;D. Chéreau;K. Henda;R. Safari;P. Leprince
中科院分区：
文献类型：
--
作者：
A. Granier;D. Chéreau;K. Henda;R. Safari;P. Leprince
研究了光光测定法监测表面波产生的 O2-N2 微波放电中氧原子浓度的有效性。在内径 16 毫米的石英管中，在托尔范围内的压力下，通过气流产生等离子体。首先，表明可以从光量测定信号的纵向轮廓推断出光量测定的可靠性。其次，氧原子的绝对浓度是根据实验光光测量信号估计的，并且与等离子体下游真空紫外（VUV）吸收同时测量的浓度令人满意地一致。此外，在改变氮百分比（0%–100%）时，有证据表明光化信号与 VUV 吸收测量的浓度成正比。此外，研究表明，纯氧等离子体中氧解离率仅为2%，而氮含量超过20%的混合物则达到15%（433 MHz）或30%（2450 MHz）。添加后 [O] 急剧增加...
The validity of actinometry to monitor oxygen atom concentration in O2‐N2 microwave discharges created by surface wave is investigated. The plasma is created with a gas flow in a quartz tube of inner diameter 16 mm at pressures in the Torr range. First, it is shown that the reliability of actinometry can be deduced from the longitudinal profile of the actinometry signal. Second, absolute concentrations of oxygen atoms are estimated from the experimental actinometry signal and agree satisfactorily with concentrations simultaneously measured by vacuum ultraviolet (VUV) absorption downstream from the plasma. Moreover, upon varying the nitrogen percentage (0%–100%), it is evidenced that the actinometry signal is proportional to the concentration measured by VUV absorption. Furthermore, it is evidenced that the oxygen dissociation rate is only 2% in pure oxygen plasmas, while it reaches 15% (433 MHz) or 30% (2450 MHz) for mixtures containing more than 20% of nitrogen. This drastic increase in [O] upon the addi...