摘要
本文以扫描电镜中样品负荷问题为背景。用Monte-Carlo法模拟了绝缘样品PMMA(C_5H_8O_2)在不同入射能量Ep(0.5-20Kev)和入射角θ_0(0°～45°)在扫描电镜中的二次电子产生和逃逸过程。模拟中考虑了背散射电子和二次电子的再激发对总二次电子产额的贡献,得到样品出射电子数与入射电子数之比δ的变化规律。模拟结果表明,δ随Ep的增加而下降、并随θ_0增加而增加。当Ep=0.5Kev,θ_0=45°时,δ=0.793,即接近电荷平衡。
In order to solve the charge problem in SEM, A Monte Carlo method is used to simulate the secondaries' generating and escaping in insulator, for example PMMA, with primary en-ergy Ep from 0.5 to 20kev and incident angle θ_0from 0°to 45°. Both the re-exciting proce-sses of backscattering electrons and secondaries have been considered. The curves for δ, which is the ratio of unmber for injected electrons to that for emission electrons, have been ob tained The result shows δ increases as Ep decreases and θ_0 increases. When EP=0.5kev and θ_0=45, δ=0.793. The specimen can keep charge balance nearly.
出处
《电子显微学报》
CAS
CSCD
1989年第1期27-33,共7页
Journal of Chinese Electron Microscopy Society
