５
MEASUREMENT OPERATION
TMPM5200-2
5-169
■
Cantile
Selec
Calib
calcu
torsi
Force Ca
Perfo
er calibration for calculating the interatomic force from the bending of
ver Calibration
ting Cantilever Calibration from the SPM Scan menu opens the Cantilever
ration window, in which you can specify the cantilever calibration values for
lating interatomic force and friction force that are obtained from bending and
on of the cantilever, respectively.
libration
rm cantilev
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 appears 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 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
d
2
v
0
v
1
v
2
1
2
1
2
V
V
d
d
a
−
−
=
