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.
Original language | English |
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Article number | 5009064 |
Journal | Royal Society Open Science |
Volume | 8 |
Issue number | 7 |
DOIs | |
Publication status | Published - Jul 2021 |
Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2021 The Authors.
Keywords
- current-voltage characteristics
- field emission
- scanning tunnelling microscopy
- surface imaging