放电参量对射频容性耦合等离子体电子密度的影响

Influence of discharge parameters on electron density of RF capacitively coupled plasma

为了提高射频容性耦合等离子体电子密度,研究放电参量对其的影响。通过采用朗缪双探针法诊断分析了放电气压、气体组分、射频功率以及掺Hg等放电参量对圆柱形射频容性耦合等离子体放电装置的电子密度的影响。结果表明:随放电气压的增加,电子密度呈现出先增大后减小的变化,在30Pa-550Pa下,电子密度随气压的增大而增加,在550Pa-650Pa下,电子密度随气压的增大而减小;往Ar中通入一定体积分数的He,有增加等离子体电子密度的影响,且当He的体积分数为15%时,电子密度最大;等离子体电子密度随射频功率的增大而增加;向Ar中掺少量的Hg,有明显增加等离子体电子密度的效果。

Effects of discharge parameters on the electron density was studied to improve the electron density of RF capacitively coupled plasma. The electron density of Cylindrical radio frequency capacitively coupled plasma discharge device was studied by using Langmuir double probe with RF discharge pressure, gas composition, RF power and doped Hg. The results show that the electron density increases first and then decreases with the increase of discharge pressure. The electron density raises with the increase of the pressure at 30Pa-550 Pa, and reduces with the increase of the pressure at 550Pa-650 Pa. A certain volume fraction of He has an effect on increasing plasma electron density. When the volume fraction of He is 15%, the electron density is the largest. The electron density raises with the increase of RF power. And adding a small amount of Hg to Ar has a significant effect on increasing the plasma electron density.