Journal article
Charging of carbon thin films in scanning and phase-plate transmission electron microscopy
A systematic study on charging of carbon thin films under intense electron-beam irradiation was performed in a transmission electron microscope to identify the underlying physics for the functionality of hole-free phase plates. Thin amorphous carbon films fabricated by different deposition techniques and single-layer graphene were studied.
Clean thin films at moderate temperatures show small negative charging while thin films kept at an elevated temperature are stable and not prone to beam-generated charging. The charging is attributed to electron-stimulated desorption (ESD) of chemisorbed water molecules from the thin-film surfaces and an accompanying change of work function.
The ESD interpretation is supported by experimental results obtained by electron-energy loss spectroscopy, hole-free phase plate imaging, secondary electron detection and x-ray photoelectron spectroscopy as well as simulations of the electrostatic potential distribution. The described ESD-based model explains previous experimental findings and is of general interest to any phase-related technique in a transmission electron microscope.
Language: | English |
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Year: | 2018 |
Pages: | 252-266 |
ISSN: | 18792723 and 03043991 |
Types: | Journal article |
DOI: | 10.1016/j.ultramic.2017.09.009 |
ORCIDs: | Beleggia, Marco |