摘要
在磁控溅射系统阴极靶施加同轴可调约束磁场显著改善了系统放电特性。研究了在Ar气放电系统伏安特性随不同的气压、溅射电压变化规律。采用同轴平面探针诊断距阴极 60mm、1 1 0mm和 2 30mm三个不同位置收集电流密度 ,负偏压 1 50V。实验结果表明存在不同的开放约束磁场和气压下放电特性符合I∝Vn(n≈ 1 2～ 1 5) ,开放约束磁场降低了系统的放电电压 ,增强了等离子体的引出效果 ,提高了系统在较低真空度的放电稳定性。轴向开放约束磁场显著提高了收集电流密度 ,离子收集通量在距阴极 2 30mm的位置达到 9 5mA/cm2 。收集电流密度达到饱和值后不再受轴向开放约束磁场强度和工作电流的影响。根据磁流体理论讨论了引起系统中伏安放电特性的变化原因。
Application of an open, adjustable, and co-axially oriented confining magnetic field to the cathode favorably improves the discharge characteristics in magnetron sputtering. Influence of Ar pressure and sputtering voltage on the discharge characteristics were studied. It was found that the I-V characteristics follow the rule of I∝Vn (n=1.2-1.5) for different magnetic field distributions and gas pressures. The results also showed that the magnetic field lowers the discharge voltage, improves the plasma extraction, and betters the discharge stability in fairly low vacuum. In addition, the magnetic field considerably increases the collection current. For instance, the ion flux can be as high as 9.5 mA/cm2, 230 mm away from the cathode under an Argon pressure of 0.18 Pa. After saturation, little influence of the field on the collection current can be observed. Possible mechanism was discussed with magneto hydrodynamics theory.
出处
《真空科学与技术》
EI
CSCD
北大核心
2003年第4期243-247,共5页
Vacuum Science and Technology
