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ANALYSIS OPERATION
6.17 SPM SCAN MENU
In the process mode you can select only Cantilever Calibration and Scanner Calibration.
■
Cantilever Calibration
Selecting Cantilever Calibration from the SPM Scan menu opens the Cantilever
Calibration window, in which you can specify the cantilever calibration values for
calculating interatomic force and friction force that are obtained from bending and
torsion of the cantilever respectively.
Force Calibration
Perform cantilever calibration for calculating interatomic force from the bending of the
cantilever.
The interatomic force is calculated based on the following equation.
]
)[
(
0
nN
V
V
ka
F
−
=
•
Apply
When the Apply check box is checked, the force image or force curve is displayed
with an interatomic-force value calculated from the applied voltage.
•
Spring Constant k [N/m]
Enter the spring constant of the cantilever in this input box.
•
Sensitivity a [nm/V]
This is the factor related to the sensitivity of the optical lever method.
•
Reference V
0
[V]
Enter the Force signal value that is obtained when the force applied to the cantilever
is zero in the Reference V0 [V] input box. This value depends upon the instrument
or cantilever used. Click on the Apply check box to remove the check mark; acquire
a force curve; then calculate it. When the
following force curve is obtained,
calculate each parameter as follows.
V
d
d
1
V
2
V
1
V
0
d
2
1
2
1
2
V
V
d
d
a
−
−
=
TMPM5200-2
6-113
