不同带电情况下介质材料二次电子发射特性研究

Study of Characteristic for Secondary Electron Emission of Dielectric with Different Surface Chargings

摘要: 空间材料二次电子发射特性是决定航天器表面带电速率和充电平衡电位水平的重要参数。本文利用1～5 keV的脉冲电子束开展了聚酰亚胺（kapton）、玻璃盖片和光学太阳反射镜（OSR）材料的二次电子发射系数（δ）测试，并完成了介质材料表面不同充电情况下的二次电子发射特性研究。研究结果表明，在入射电子能量为1～5 keV范围内材料二次电子发射系数随入射电子能量上升而下降，同时当二次电子发射系数大于1时，材料表面将累积正电荷，二次电子发射系数下降，当二次电子发射系数小于1时，材料表面将累积负电荷，二次电子发射系数将增加。

Abstract: The secondary electron emission (SEE) process is very important for spacecraft surface charged rate and balanced potential. The SEE coefficients (δ) of kapton，cover glass and optical solar reflector (OSR) materials were measured with 1.5 keV pulsed electron irradiation, and the SEE yield of dielectric material with different surface charges was investigated. The results indicate that the SEE yield is observed to be larger at lower projectile energy in the region of 1.5 keV. The SEE coefficients decrease with positive charging of dielectric when δ is more than 1 and increase with negative charging of dielectric when δ is lower than 1.