旋转横向磁场对电弧离子镀弧斑运动的影响

Influence of Rotating Transverse Magnetic Field on Motion of Cathode Spot in Arc Ion Plating

研究了旋转横向磁场对电弧离子镀弧斑运动的影响规律，采用有限元分析软件FEMM对旋转横向磁场的分布进行了模拟，考察了不同频率（80～210Hz）及电磁线圈励磁电流对弧斑运动的影响。从电弧斑点放电的物理机制出发，探讨了不同频率和磁场线圈电流对电弧离子镀弧斑运动的影响机制。结果表明，随着旋转横向磁场强度和频率的提高，使弧斑逐渐从聚集的斑点态（或者弱分散的团絮态）转变为大面积分布在靶面较强的分散弧斑絮线，最后转变为完全分布在整个靶面的强分散弧斑线，弧斑分裂强烈，产生的弧光等离子体更加均匀细腻。随着瞬态弧斑线在靶面分布面积的增加，弧压增加，弧电流密度急剧下降，靶材利用率达到85％以上。旋转横向磁场的应用，带来了弧斑大面积稳定放电、等离子离化率、密度及靶材利用率大幅度提高的多重效应。

The motion of cathode arc-spots, originated from the newly-developed technique of rotating transverse magnetic field （RTMF）generated with an adjustable electromagnetic coil in arc ion plating reactor, was experimentally e- valuated, empirically approximated, physically modeled and numerically simulated in finite element method. The influence of the frequency and current of the coil on the magnetic field distribution and motion of the arc-spots was investigated. The results show that the RTMF frequency and intensity strongly affect the arc-spots motion, arc discharge and arc plasma. For instance, as the frequency and intensity increased, the slow-moving, aggregated, big bright spots （fragmented group floe- state） gradually changed into irregularly and widely dispersed strong floc-lines, accompanied by the larger coverage on tar- get surface, faster arc-spots motion, rapidly reduced current density, more uniform plasma and bigger target utility rate （up to 85 % or higher）. We conclude that the novel RTMF technique results in largearea steady discharge and significant in- creases of plasma ionization rate, plasma intensity, and target utility rate.