金属材料二次电子发射系数的复合半经验模型  

Combined Semi-empirical Model for Secondary Electron Yield of Metals

作　　者：张雨婷 杨晶[1] 杨兆伦 张娜[1] 崔万照[1] ZHANG Yuting;YANG Jing;YANG Zhaolun;ZHANG Na;CUI Wanzhao(National Key Laboratory of Science and Technology on Space Microwave,China Academy of Space Technology(Xi’an),Xi’an 710110,China;School of Astronautics,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China)

机构地区：[1]中国空间技术研究院西安分院空间微波技术重点实验室,西安710110 [2]南京航空航天大学航天学院,南京211106

出　　处：《高电压技术》2023年第9期3819-3826,共8页High Voltage Engineering

基　　金：国家自然科学基金(62101434);空间微波重点实验室基金(6142411112205)。

摘　　要：二次电子发射模型的精度对精确预测空间大功率微波部件微放电阈值有很大影响。针对现有二次电子发射唯象模型的不足,采用分段函数的思想建立了一种计算金属材料二次电子发射系数(secondary electron yield,SEY)的复合半经验模型。该模型以Vaughan模型计算入射能量Ep<Epm(二次电子发射系数最大值所对应的入射电子能量)时材料的二次电子发射系数,以文中建立的半经验模型计算入射能量Ep≥Epm时材料的二次电子发射系数,并利用钼和银两种材料二次电子发射系数的测试结果对复合半经验模型进行了验证。模拟结果表明,复合半经验模型能够对溅射清洗前后及不同入射极角条件下的SEY进行精确表征,相对误差的平均值和均方差明显低于Vaughan模型和半经验模型,且在不同入射极角条件下该模型具有较好的稳定性,在很大程度上提高了二次电子发射模型与实验数据拟合的准确性。该模型有望应用于空间大功率微波部件的微放电功率阈值的模拟。The accuracy of the secondary electron yield(SEY)model has a significant impact on the exact prediction of the multipcator thresholds.In view of the shortcomings of the existing SEY(secondary electron yield)phenomenological model,a new combined semi-empirical model for calculating the SEY is established by using the idea of piecewise function.The model utilizes the corrected Vaughan model to calculate the SEY when the incident energy Ep<Epm(Epm refers to the incident electron energy corresponding to the maximum value of secondary electron emission yield),and a semi-empirical model is establishedto calculate the SEY when the incident energy Ep≥Epm.The combined semi-empirical model is validated by experimental results of the SEY for molybdenum and silver.The simulation results show that the combined semi-empirical model can accurately characterize the SEY before and after sputtering cleaning as well as different incident angles.The average and mean square deviation of relative errors are significantly lower than those of the Vaughan model and semi-empirical model.Moreover,the model has good stability under different incident electron angles,which can greatly improve the fitting accuracy between the simulation results of secondary electron emission model and test data.This model is expected to be applied to simulate the multipactor threshold of high-power microwave components in space.

关 键 词：二次电子发射 空间大功率微波部件 唯象模型 分段函数 微放电 

分 类 号：O462.2[理学—电子物理学]