气体对低能可变压力扫描电子显微镜中背散射电子发射和检测的影响。

Gas effect on the emission and detection of the backscattered electrons in a VP-SEM at low energy.

作者信息

Hafsi Z, Mansour O, Kadoun A, Khouchaf L, Mathieu C

机构信息

L2MSM Laboratory, Physics Department, Faculty of Exact Sciences, Djilali Liabes University BP.89 Sidi Bel-Abbes 22000, Algeria.

L2MSM Laboratory, Physics Department, Faculty of Exact Sciences, Djilali Liabes University BP.89 Sidi Bel-Abbes 22000, Algeria..

出版信息

Ultramicroscopy. 2018 Jan;184(Pt A):17-23. doi: 10.1016/j.ultramic.2017.08.002. Epub 2017 Aug 12.

DOI:10.1016/j.ultramic.2017.08.002

PMID:28837892

Abstract

The effect of the electron beam skirting on the emission and detection of the backscattered electrons (BSE) in a low vacuum scanning electron microscope is investigated at low energy regime. Monte Carlo computed dependencies of the BSE distribution on the water vapor and air pressure shown a significant increase of the extent of the BSE exit zone. The pressure variation has however a little effect when helium gas is used. A new approach based on the comparison between the sizes of the skirt and the BSE exit zone on the specimen surface provides a useful tool to determine the operating pressure range that ensures minimal degradation of the lateral resolution in BSE imaging mode.

摘要

在低能状态下，研究了低真空扫描电子显微镜中电子束边缘对背散射电子（BSE）发射和检测的影响。蒙特卡洛计算得出的BSE分布与水蒸气和气压的相关性表明，BSE出射区域的范围显著增加。然而，当使用氦气时，压力变化的影响较小。一种基于比较样品表面边缘尺寸和BSE出射区域大小的新方法，为确定操作压力范围提供了一个有用的工具，该压力范围可确保BSE成像模式下横向分辨率的最小退化。