高性能电子枪的物理设计  

Physical Design of High Performance Electron Gun

作　　者：石晓倩 刘佳辉 陈雪颖 郭方准[1] SHI Xiao-qian;LIU Jia-hui;CHEN Xue-ying;GUO Fang-zhun(School of Mechanical Engineering,Dalian Jiaotong University,Dalian 116028,China)

机构地区：[1]大连交通大学机械工程学院,辽宁大连116028

出　　处：《真空》2023年第3期62-66,共5页Vacuum

基　　金：辽宁省教育厅“攀登学者”项目资助(8800002)。

摘　　要：为测量电导率较低材料的二次电子发射系数,设计了一种能量在0~2keV之间可调、束斑直径可调、可偏转、可脉冲的高性能电子枪。根据电子枪的性能指标对其电子发射、电子光学系统和电位关系进行物理设计,通过对控制极施加脉冲电压,实现电子束的脉冲发射。利用CST软件对电子枪建模并进行仿真分析,得到不同聚焦极电压对束斑尺寸的影响。仿真结果表明,在阴极电压为-1000V、控制极为-1005V、第一阳极为-880V时,随着聚焦电压由-400V增加到1000V,束斑直径由0.2mm增加到10mm,两者几乎成正比例关系。通过对比两种偏转组件,得出四极静电偏转器更适合在同一空间内使用,在工作距离为30mm、偏转电压为200V时,偏转灵敏度可达到34mm/kV,对应的偏转角为12.8°。The measurement of secondary electron emission coefficient is very important for the development of vacuum electronic devices.To measure the secondary electron emission coefficient of materials with low electrical conductivity,it is necessary to design a high performance electron gun with adjustable energy,beam spot diameter,deflection and pulse.According to the performance index of the electron gun,its electron emission,electron optical system and potential relationship are preliminarily designed.The pulse emission of electron beam was realized by applying pulse voltage to the control pole.The CST software was used to model and simulate the electron gun,the influence of focusing pole voltage on the beam spot size was obtained,and the effect of the deflector electrode was simulated.The results show that when the cathode voltage is-1000V,the control electrode voltage is-1005V,and the first anode voltage is-880V,as the focusing voltage increases from-400V to 1000V,the beam spot diameter increases from 0.2mm to 10mm,the relationship between them is almost directly proportional.The quadrupole electrostatic deflector is more suitable for use in the same space by comparing two deflection components.When the working distance is 30mm and the deflection voltage is 200V,the deflection sensitivity can reach 34mm/kV and the corresponding deflection angle is 12.8°.The design of the electron gun is reasonable and meets the requirements of the index,it can be used to measure the secondary electron launcher.

关 键 词：电子枪 电子光学系统 CST仿真 二次电子 

分 类 号：TL82[核科学技术—核技术及应用]