Nanosurf easyScan 2 AFM, Руководство по эксплуатации

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TATIC
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ORCE
65
Measurement modes
This chapter instructs you on how to use the Dynamic Force, Static Force,
Phase contrast, the Force Modulation, and Spreading Resistance modes. If
you are unfamiliar with the Atomic Force Microscopy Technique, it is rec-
ommended to first read the chapter
AFM Theory (p.83).
The amount of available modes depends on the Scan head and the available
modules built into the easyScan 2 controller. The modules required to be
able to use a certain operating mode are listed in table
Operating modes and
required modules . The modes can be divided into the static operating modes
that control the Z-position control using the Cantilever deflection, the
dynamic operating modes that control the Z-position using the vibration
amplitude.
Static Force
In the Static Force mode, the ‘static’ deflection of the cantilever is used as
the error signal for the Z-Controller. The Set point in Newton is calculated
by multiplying the deflection with the spring constant of the selected can-
tilever. In order to minimize tip/sample wear, the force set point should be
made as small as possible. In some cases, even a negative set point (i.e. an
adhesive force) may work, but when the tip momentarily loses contact with
the sample due to some disturbance, the Z-Controller will always fully
retract the cantilever from the sample. Moreover, working in this range may
cause image artefacts due to instabilities in the tip-sample contact.
Operating mode Required modules
Static force AFM Basic
Dynamic force AFM Basic, AFM Dynamic
Phase contrast AFM Basic, AFM Dynamic, AFM Mode Extension
Force Modulation AFM Basic, AFM Dynamic, AFM Mode Extension
Spreading Resistance AFM Basic, AFM Dynamic, AFM Mode Extension
Operating modes and required modules