低气压下空心阴极辉光放电等离子体的特性

Characteristics of hollow cathode glow discharge plasma under low pressure

为掌握10-2Pa～10-3Pa的低气压、磁场条件下空心阴极辉光等离子体的特性及其与常规辉光放电伏安特性的区别,我们对其伏安特性和电子密度进行了测量。实验结果表明:低气压、磁场条件下空心阴极辉光放电的整个过程可分为三个不同阶段,即随着电流的增大,依次为起辉阶段、空心阴极放电阶段和反常辉光放电阶段。其中,起辉阶段与空心阴极放电阶段的伏安特性与常规辉光放电的伏安特性曲线不同,而反常辉光放电阶段类似。实验证实了电子密度随电流增大而增大的关系,实验结果表明,在轴线方向上,阳极附近的电子密度大于阴极附近的;在与轴线垂直的平面上,电子密度差别不大。

In order to know the characteristics of hollow cathode glow plasma under the condition of low pressure （10-2Pa~ 10-3pa） and magnetic field, and the differences between the volt-ampere characteristic under those conditions and the conventional glow discharge, we measured the volt-ampere characteristic and electron density. The experimental results show that the whole discharge process of the hollow cathode glow discharge under the condition of low pressure and magnetic field can be divided into three stages. From the low current to the high current, they are starter stage, hollow cathode discharge stage and abnormal glow discharge stage. In the starter stage and hollow cathode discharge stage, the volt-ampere characteristic is different from the conventional glow discharge, while in the abnormal glow discharge stage, the two volt- ampere characteristics are similar to each other. The results confirmed that the electron density increases with the increasing of glow current. And in the axial direction, the electron density near the anode is greater than that near the cathode; in the vertical plane of the axis, the electron density changes little.