电子轰击离子源离子聚焦性能仿真研究  

Simulation Study on Ion Focusing Performance of Electron Impact Ion Source

作　　者：李冠华 冯焱[1] 成永军[1] 孙雯君[1] 陈联[1] 冯天佑[1] 王星辉 杨喆 LI Guanhua;FENG Yan;CHENG Yongjun;SUN Wenjun;CHEN Lian;FENG Tianyou;WANG Xinghui;YANG Zhe(Science and Technology on Vacuum Technology and Physics Laboratory,Lanzhou Institute of Physics,Lanzhou 730000,China)

机构地区：[1]兰州空间技术物理研究所真空技术与物理重点实验室,兰州730000

出　　处：《真空与低温》2025年第2期148-155,共8页Vacuum and Cryogenics

基　　金：甘肃省首席科学家负责制项目(23ZDKA016)。

摘　　要：针对兰州空间技术物理研究所自研小型四极质谱计的电子轰击离子源(EI源),对其聚焦性能进行了仿真研究。利用仿真软件Simion8.0,采用控制变量法研究了EI源聚焦极电参数、极板间距离、极板孔径大小对离子聚焦性能的影响。结果表明:聚焦极电压与电离室电压压差越大,聚焦性能越好,当聚焦极电压增大且逐渐接近电离室电压时,其聚焦性能会快速变差;同时增大各极板间距时,离子聚焦性能先变好后变差,最佳聚焦性能出现在电离室下极板和聚焦极以及聚焦极和引出极的间距都为1.25 mm时;减小电离室下极板孔径以及引出极极板孔径时,聚焦性能会显著变好,但传输效率会明显降低,当电离室下极板和引出极极板孔径不变时,改变聚焦极极板孔径,其聚焦性能随着聚焦极极板孔径变小而变好,当聚焦极孔径为1.6 mm或2.0 mm时聚焦性能最佳。以上仿真结果为EI源的工程化设计与优化提供了关键数据支撑。In order to simulate the focusing performance of the electron impact ion source(EI source)of the small quadrupole mass spectrometer developed by Lanzhou Institute of Physics,the effects of the focusing electrode parameters of the EI source,the distance between the plates,and the pore size of the plate on the ion focusing performance were studied by using the simulation software Simion8.0.The results show that the greater the voltage difference between the focusing pole voltage and the ionization chamber voltage,the better the focusing performance,and the focusing performance will deteriorate rapidly when the focusing pole voltage increases and gradually approaches the ionization chamber voltage.When the,spacing of each plate is increased at the same time,the ion focusing performance first gets better and then worse,the optimal focusing performance occurs when the distance between the electrode plate and the focusing electrode,as well as between the focusing electrode and the extraction electrode,in the ionization chamber is 1.25 mm.When the aperture of the lower plate and the aperture of the leading plate are reduced at the same time,the focusing performance will be significantly improved,and when the aperture of the lower plate and the leading plate of the ionization chamber remain unchanged,the aperture of the focusing plate will be changed,and the focusing performance will generally improve with the decrease of the aperture of the focusing plate,but the transmission efficiency will be reduced,and the best focusing performance mainly occurs when the aperture of the focusing pole is 1.6 mm or 2.0 mm.The above simulation results provide a data reference for the subsequent production of EI sources.

关 键 词：EI源 数值仿真 聚焦离子束 

分 类 号：TB773[一般工业技术—真空技术]