Fig. 1. Interaction between high-energy electrons and PMMA thin film.高能电子与PMMA薄膜相互作用示意图

Fig. 2. Flow diagram of the charging process.计算流程示意图

Fig. 3. Simulated (lines) and experimental (squares) electron total yields.电子总产额的模拟(线条)和测量(方块)结果

Fig. 4. Charges distribution along the incident direction: (a) Electron density ; (b) net charge density.样品内部入射方向电荷分布　(a) 电子密度; (b) 净电荷密度

Fig. 5. (a) Space potential and (b) electric field along the incident direction.(a) 空间电位; (b) 电场强度沿入射方向分布

Fig. 6. The surface potential V_S and emission current I_σ as function of time. 表面电位V_S和出射电子电流I_σ时变特性

Fig. 7. The transmission current I_TE and the sample current I_S as function of time. 透射电流I_TE和样品电流I_S时变特性

Fig. 8. Charging characteristics under different thicknesses: (a) Surface potential; (b) surface emission current; (c) sample current; (d) transmission current.不同厚度下的带电特性　(a) 表面电位; (b) 表面出射电流; (c) 样品电流; (d) 透射电流

Fig. 9. Charging characteristics under different beam energies: (a) Surface potential; (b) surface emission current; (c) sample current; (d) transmission current.不同入射能量下带电特性　(a) 表面电位; (b) 表面出射电流; (c) 样品电流; (d) 透射电流