摘要
离子源是磁偏转质谱计的核心,离子源的聚焦和离子引出效率对其工作性能有着重要影响。采用SIMI-ON-3D 8.0软件建立了应用于小型磁偏转质谱计的电子轰击型离子源模型,计算了离子的运动轨迹,采用相空间分析方法,得到静电透镜聚焦处离子的位置聚焦半径和速度聚焦半径,分析了离子源各参数对聚焦和离子引出效率的影响。研究结果表明当S和α狭缝分别加负偏压时,离子束在运动过程中能够两次聚焦,从而得到很好的聚焦性能和引出效率,为离子源优化设计提供重要的理论依据和实验指导。
Focusing and extraction efficiency have a significant effect on electron impact ion source （EI）. Themotion of the individual EI of a MiniatureMagnetic Sector Mass Spectrometerwas simulated by means of the ion optics simulation software package, SIMION-3DS. 0, to analyze its position and velocity. Theinfluence on its characteristics, including the focusing and velocity divergence of the emitted ion beam of the EI, through the EI parameters was evaluated. The simulated results show that If S slit and c^slit are respectively applied negative high bias potential, the ion beam can focuses two times in a individual motive process. We suggest that fine electron impact ion source can be designed, fabricated, and integrated with themass a- nalysis by optimizing the EI parameters.
出处
《真空与低温》
2013年第1期40-45,共6页
Vacuum and Cryogenics
关键词
离子源
聚焦半径
引出率
模拟
Ion source
focusing radius
extractionefficiency
simulation
