６
ANALYSIS OPERATION
Friction Force Calibration
Perform cantilever calibration for calculating friction force from the torsion of the
cantilever.
The friction force is calculated based on the following equation.
]
[
10
2
)
(
6
0
nN
d
V
V
ka
F
×
−
=
•
Apply
When the “Apply” check box is checked, the friction force image is displayed with a
friction-force value calculated from the applied voltage.
•
Spring Constant k [N/rad]
Enter the spring constant of the cantilever in the torsional direction in the “Spring
Constant k [N/rad]” input box. The spring constant is calculated from the following
equation.
(
)
2
/
3
3
t
h
l
G
wt
k
+
=
W
Substrate
Tip
l
h
t
Cantilever
•
Sensitivity a [nm/V]
This value depends upon the instrument used. Change the photodiode position (in
the X-axis), and then calibrate the sensitivity using the FFM value shown on the
AFM AMP indicator.
X-axis position
adjusting knob
X-axis+
Y-axis position
adjusting knob
Y-axis+
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TMPM5200-2
