为了提高射频空心阴极放电中的等离子体密度,通过实验和数值模拟研究了氩气环境下孔深对射频空心阴极放电的影响.在实验上利用Langmuir探针测量了射频空心阴极放电等离子体的电子数密度,并对不同孔深条件下获得的电子数密度进行了比较.利用二维流体模型模拟了空心阴极结构下的射频放电,获得了电子数密度和电离速率的分布随孔深的变化规律.模拟结果表明:大的孔深可以增加孔内强电离区域的大小,并使等离子体密度增加,这一规律与实验结果相符;当孔深与孔径的比值大于3时,等离子体密度基本达到饱和.
In order to increase the plasma density in radio-frequency (RF) hollow cathode discharge(HCD), we studied theinfluence of hole depth on RFHCD in Ar gas through experiments and numerical simulations. In the experiments, wemeasured the electron density of RFHCD using Langmuir probe, and compared the electron densities of different holedepths. We obtained the spatial-distribution of plasma density and ionization rate along with various hole depths using2-D fluid model to simulate the RFHCD. The numerical results show that increasing the hole depth can enlarge high ioni-zation region and increase plasma density in RF HCD, which is in accordance with the experimental results. Moreover,when the ratio of hole depth to hole diameter is higher than 3, the plasma density will reach its saturation value.