Open AccessElectron‐gas interactions in the environmental scanning electron microscopes gaseous detector
Author(s) -
Meredith P.,
Donald A. M.,
Thiel B.
Publication year - 1996
Publication title -
scanning
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.359
H-Index - 47
eISSN - 1932-8745
pISSN - 0161-0457
DOI - 10.1002/sca.1996.4950180701
Subject(s) - electron , environmental scanning electron microscope , signal (programming language) , electron microscope , scanning electron microscope , noise (video) , process (computing) , detector , microscope , cathode ray , electron beam induced deposition , optics , computer science , materials science , nanotechnology , physics , scanning transmission electron microscopy , computer vision , image (mathematics) , quantum mechanics , programming language , operating system
The construction of high signal‐to‐noise, artefact‐free secondary electron images in the elevated pressure conditions of an environmental SEM is a nontrivial process. The interactions of information carrying species, as well as probe beam electrons, with the chamber gas are the major reasons for such complications. In this paper, we discuss and review the present understanding of these phenomena. In addition, we outline procedures for assessing the signal‐amplifying and charge‐neutralising capabilities of an environmental gas. It is only with a knowledge of such parameters and an appreciation of the gas‐electron collision processes that one can optimise the microscope's operating parameters. Moreover, such information enables the separation of topographic detail from artefactual features in the detected electron images.