混合离子束阴极真空弧等离子体鞘层特性

基于无碰撞模型，建立了混合离子束阴极真空弧等离子体鞘层动力学模型，给出了解析表达式。针对材料改性中应用的H-Ti混合离子束，模拟计算了鞘层厚度和靶表面电场强度分别随离子密度和偏置靶压的演变规律。针对实际应用中出现的鞘层击穿和离子束散焦现象进行了理论分析，发现离子束稳定工作区域强烈依赖于离子密度和偏置靶压等参数，降低离子密度和提高靶压会增加稳定工作区域范围。

Sheath characteristics of vacuum arc plasma for mixed ion beam

The dynamic sheath model and the analytic expression of the vacuum arc plasma for mixed ion beam are presented based on the collision less model. The variations of the sheath width and electric-field strength as the function of the ion density and substrate bias voltage are calculated respectively for H-Ti mixed ion beam. The phenomena of sheath breakdown and ion beam defocusing, which usually arise in the practical application, are analyzed. It is found that the stable operating region for the mixed ion beam extremely depends on the ion density and substrate bias voltage, and reducing the ion density and increasing the substrate bias voltage can expand the stable operating region.