基于波导耦合反应腔串联的线形微波等离子体源

Novel Type of Linear Microwave Plasma Source with Two Waveguide Coupling Reactors Connected in Series

通过将两个波导耦合反应腔串联,得到了具有线形结构的微波等离子体源。利用光纤光谱仪沿等离子体轴向测量不同位置的等离子体发射光谱,对等离子体中不同基团的发射光谱强度进行了比较分析,研究了反应腔结构对等离子体均匀性的影响。实验结果表明:通过将波导耦合反应腔串联可以在引导天线表面产生圆柱状的线形等离子体,等离子体沿轴向的均匀性与引导天线外径尺寸和两端的模式转换棒的位置有关,当引导天线外径为4 mm,模式匹配棒伸入量为10 mm时,等离子体的不均匀性小于10%。

A novel type of linear microwave plasma source was developed by connecting in series two waveguide coupling reactors. The influence of the reaction cavity structure on the axial plasma distribution was investigated by measuring the optical emission spectrum at different axial positions withfiber optical spectrometer and by comparing the intensity emitted from different groups in the plasma. The results show that the newly-developed linear microwave plasma source is capable of stably generating a linear cylindrical plasma around the guide-antenna surface,and that the outer diameter of the guide-antenna and locations of the mode conversion control rods strongly affect the uniformity of axial plasm distribution. The axial non-uniformity of the plasma,generated by the novel linear microwave plasma source,with the guide antenna 4 mm in diameter and the mode conversion control rods inserted10 mm into the quartz tube on both ends,was estimated to be less than 10%.