Operating instructions

SPREADING RESISTANCE
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- If necessary, increase the size of the window to make space for the new
chart.
- Select the ‘Color map’ chart type by .
- Select the ‘Amplitude’ signal by .
Spreading Resistance
The Spreading Resistance mode is an extension of the static force mode.
The static force acting on the cantilever is used to produce a topography
image of the sample. Simultaneously, changes in the spreading resistance
from the cantilever tip to a ground contact on a sample can be imaged by
measuring changes in tip current whilst a fixed voltage is applied to the tip.
Proceed as follows to operate the easyScan 2 AFM in the Spreading Resist-
ance mode:
- Electrically connect the sample to the Ground connector on the easyScan
2 AFM Scan head (figure Parts of the scan head (p.15)) via a 100 kOhm
resistor, in order to prevent damage to the tip due to an excessive current.
For best results, the sample should be electrically isolated except for the
connection mentioned above.
- Select a cantilever:
CDT-NCLR should be used for samples where a high force is needed to
penetrate a surface oxide layer.
CONT-PtIr cantilevers can be used on delicate samples. The applied volt-
age should be small, because high currents may cause the conducting layer
on the tip to evaporate. Also, applied forces should be very small to prevent
damage to the conducting layer.
NCL-PtIr cantilevers could be used in combination with non-contact
topography measurements, but damage to the tip is likely.
Important!
• Standard CONTR cantilevers can not be used due to the surface oxide
on the tip, and the semiconducting contact between the tip and the sam-