Nanosurf easyScan E-STM, Руководство по эксплуатации

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• If each image looks different:
• If the scan lines in ‘LineView’ are unstable and the image in the ‘TopView’
is not ‘sharp’:
The graphite surface
In a good top view image of graphite you will see a pattern consisting of
white, grey and black spots. It looks like a three dimensional image of balls
lying next to each other, but be careful: these are not the single atoms!
To interpret the image correctly you must first be aware that bright spots
show high points and dark spots low ones (except in ‘LineMath’ ‘Derive’).
In the lattice model of graphite one can see that there are two different
positions of the carbon atoms in the graphite crystal lattice: One with a
neighbouring atom in the plane below (grey) and one without a neighbour
in the lattice below (white). As a consequence, the electrical conductivity of
the graphite surface varies locally slightly so that the atoms without neigh-
bours appear higher than the others.
F
IRST
M
EASUREMENTS
T
HE GRAPHITE SURFACE