Usage of Segmental Ionization Detector in Environmental Conditions

0205646 - UPT-D 20030028 RIV US eng J - Journal Article
Autrata, Rudolf - Jirák, J. - Schneider, L.
Usage of Segmental Ionization Detector in Environmental Conditions.
Microscopy and Microanalysis. Roč. 9, Sup. 3 (2003), s. 142 - 143. ISSN 1431-9276. E-ISSN 1435-8115.
[MC 2003. Dresden, 07.09.2003-12.09.2003]
R&D Projects: GA AV ČR IBS2065107; GA ČR GA102/01/1271
Institutional research plan: CEZ:AV0Z2065902
Keywords : segmental ionization detector * scanning electron microscope * gaseous environment
Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering
Impact factor: 1.648, year: 2003

Environmental scanning electron microscope operates with the gaseous environment in the specimen chamber. This environment causes specific conditions for the detection of signal electrons. Classical Everhart-Thornley detector cannot be exploited for the detection of secondary electrons because of the impossibility to use high enough electric field in a gaseous environment to add sufficient energy to secondary electrons for efficient scintillation. Ionization detector is therefore used for the detection of signal electrons in environmental SEM most frequently. At this detector a plate electrode with positive potential is positioned above the specimen, which lays on a grounded specimen holder. At operation signal electrons from the specimen are accelerated in electrical field to the positive electrode and are amplified in the process of impact ionisation in a gaseous environment. The positive electrode of the ionisation detects products of ionisation collisions caused by secondary, backscattered and primary electrons.
Permanent Link: http://hdl.handle.net/11104/0101259