极板类型及极性对容性耦合等离子体均匀性的影响

Influence of Electrode Type and Polarity on Uniformity of Capacitive Coupled Plasma

使用朗缪尔双探针诊断方法,研究了圆孔刻槽极板和极性电极(相位差Δφ=00和Δφ=1800)在不同条件下对13.56 MHz容性耦合等离子体均匀性的影响。同时提到了点亮问题对等离子体分布的影响。实验结果表明:圆孔刻槽极板和极性电极均可避免点亮问题,提高等离子的均匀性。圆孔刻槽极板将电子密度的均匀性由85.6%提高到93.7%(功率为50W),由63.6%提高到84.6%(功率为300 W);反相位极性电极的电子密度的均匀性可达到90%以上(功率为50 W)和80%以上(功率为300 W)。

Here,we experimentally addressed the light-up issue of the 13. 56 MHz,capacitive coupled plasma.The effect of the two electrode configurations,one with an array of blind holes and the other with a phase difference（ Δφ in 00~ 1800range）,on the plasma uniformity was investigated with Langmuir double-probe. The results show that the electrode with the two electrode configurations can solve the light-up problem and improve the plasma uniformity. To be specific,the electrode with an array of blind holes improved the uniformity of the electron density from 85. 6% to 93. 7% at a power of 50 W and from 63. 6% to 84. 6% at 300 W,respectively. And the electrode with a phase difference of 180° increased the uniformity of electron density to over 90% at 50 W and above 80% at300 W,respectively. Possible mechanisms responsible for the uniformity improvement were also tentatively discussed.