Nanosurf easyScan E-STM, Руководство по эксплуатации

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Approaching the tip
To start measuring, the sample must be very close to the tip to enable a
tunneling current to flow. Approaching the sample without touching the
tip, is a delicate operation carried out in three steps. The LED on the scan
head tells you about the distance between the tip and the sample:
LED orange:
z-piezo fully extended toward the sample: the distance
is too big, not tunneling current can be detected.
LED red: z-piezo fully retracted: The tip touched or ‘crashed into’
the sample, the tunneling current is too high.
LED green: z- piezo within the measuring range: tunneling cur-
rent should be flowing.
1. Coarse approach by hand
- Push the sample holder (figure components, 8 f) carefully to within 1mm
distance of the tip.
F
IRST
M
EASUREMENTS
A
PPROACHING THE TIP