Cazaux Jacques
Laboratoire d'Analyse des Solides Surfaces et Interfaces, Faculté des Sciences, Boite Postale 1039, 51687 Reims Cedex 2, France.
Microsc Microanal. 2004 Dec;10(6):670-84. doi: 10.1017/s1431927604040619.
The physical mechanisms involved in electron irradiation of insulating specimens are investigated by combining some simple considerations of solid-state physics (trapping mechanisms of electrons and secondary electron emission) with basic equations of electrostatics. To facilitate the understanding of the involved mechanisms only widely irradiated samples having a uniform distribution of trapping sites are considered. This starting hypothesis allows development of simple models for the trapped charge distributions in ground-coated specimens as investigated in electron probe microanalysis (EPMA) as well as for the bare specimens investigated in scanning electron microscopy (SEM) and environmental SEM (ESEM). Governed by self-regulation processes, the evolution of the electric parameters during the irradiation are also considered for the first time and practical consequences in EPMA, SEM, and ESEM are deduced. In particular, the widespread idea that the noncharging condition of SEM is obtained at a critical energy E2 (where delta + eta = 1 with delta and eta yields obtained in noncharging experiments) is critically discussed.
通过将固态物理学的一些简单考量（电子俘获机制和二次电子发射）与静电学基本方程相结合，研究了绝缘样品电子辐照所涉及的物理机制。为便于理解所涉及的机制，仅考虑具有均匀俘获位点分布的广泛辐照样品。这一初始假设使得能够为电子探针微分析（EPMA）中研究的接地涂层样品以及扫描电子显微镜（SEM）和环境扫描电子显微镜（ESEM）中研究的裸样品的俘获电荷分布建立简单模型。在自调节过程的支配下，首次考虑了辐照过程中电参数的演变，并推导了在EPMA、SEM和ESEM中的实际后果。特别是，对广泛存在的一种观点进行了批判性讨论，即认为在临界能量E2（在非充电实验中得到的δ + η = 1，其中δ和η为产额）下可实现SEM的非充电状态。
