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Non-topographic current contrast in scanning field emission microscopy.

ABSTRACT: In scanning field emission microscopy (SFEM), a tip (the source) is approached to few (or a few tens of) nanometres distance from a surface (the collector) and biased to field-emit electrons. In a previous study (Zanin et al. 2016 Proc. R. Soc. A 472, 20160475. (doi:10.1098/rspa.2016.0475)), the field-emitted current was found to change by approximately 1% at a monatomic surface step (approx. 200 pm thick). Here we prepare surface domains of adjacent different materials that, in some instances, have a topographic contrast smaller than 15 pm. Nevertheless, we observe a contrast in the field-emitted current as high as 10%. This non-topographic collector material dependence is a yet unexplored degree of freedom calling for a new understanding of the quantum mechanical tunnelling barrier at the source site that takes into account the properties of the material at the collector site.

SUBMITTER: Bertolini G

PROVIDER: S-EPMC8278050 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Non-topographic current contrast in scanning field emission microscopy.

Bertolini G G Gürlü O O Pröbsting R R Westholm D D Wei J J Ramsperger U U Zanin D A DA Cabrera H H Pescia D D Xanthakis J P JP Schnedler M M Dunin-Borkowski R E RE

Royal Society open science 20210714 7

In scanning field emission microscopy (SFEM), a tip (the source) is approached to few (or a few tens of) nanometres distance from a surface (the collector) and biased to field-emit electrons. In a previous study (Zanin et al. 2016 Proc. R. Soc. A 472, 20160475. (doi:10.1098/rspa.2016.0475)), the field-emitted current was found to change by approximately 1% at a monatomic surface step (approx. 200 pm thick). Here we prepare surface domains of adjacent different materials that ...[more]

PMID: 34295530

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