The exhaust ion stream from an electron cyclotron resonance (ECR) plasma source is investigated in detail. Two sets of coils allow for different shapes of the external field under which the plasma is created. Parameters in the form of electron density $n_{e}$ , electron temperature $T_{e}$ , and ion energy distribution function (IEDF) are evaluated using Langmuir probes and retarding field energy analyzers (RFEAs). Parameters are evaluated under 10 and 20 W of microwave energy at pressures in argon between $1\times 10^{-3}$ and $2\times 10^{-3}$ mbar. In the middle of the plasma, we see electron temperatures in the range of 4–5 eV for most measurements and electron densities of up to $5\times 10^{16}/\text{m}^{3}$ in agreement with particle and power balance models. For a purely expanding magnetic field, the detailed IEDFs indicate a directed ion speed within the plasma column of up to $3.1\times 10^{3}$ m/s with respect to the low-energy background. With increasing downstream magnetic field, the low-energy part of the IEDFs vanishes downstream of the magnetic mirror. Structures with energies increasing in the radial direction appear as radial confinement improves.

中文翻译：

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小型 ECR 等离子体源下游的详细密度和离子能量分布

详细研究了来自电子回旋共振 (ECR) 等离子体源的排出离子流。两组线圈允许产生等离子体的不同形状的外场。电子密度形式的参数 $n_{e}$ , 电子温度 $T_{e}$ 和离子能量分布函数 (IEDF) 使用朗缪尔探针和延迟场能量分析仪 (RFEA) 进行评估。参数是在 10 和 20 W 微波能量下在氩气压力下评估的 $1\乘以 10^{-3}$ 和 $2\times 10^{-3}$ 毫巴。在等离子体的中间，我们看到大多数测量的电子温度在 4-5 eV 范围内，电子密度高达 $5\times 10^{16}/\text{m}^{3}$ 与粒子和功率平衡模型一致。对于纯粹扩展的磁场，详细的 IEDF 表明等离子体柱内的定向离子速度高达 $3.1\乘以 10^{3}$ m/s 相对于低能量背景。随着下游磁场的增加，IEDF 的低能量部分在磁镜下游消失。随着径向限制的改善，出现径向能量增加的结构。