JEOL JSPM-5200 Instructions Manual page 161

５ MEASUREMENT OPERATION
■ Observation of an image
1.
To start scans, click on the Scan button of the SPM Parameters window.
The following images will be obtained.
2.
Increase the input sensitivity of the lock-in ampl
d irection) using the SENSITIVITY setting key (▼) in the range in which the
signa
3.
Specify the SPM parameters for usual operation so that you can obtain an
optimum topography image.
4.
Change the following parameters so that you can obtain an optimum friction
image.
• Oscillation level (OSC Level/V)
5-98
Sometimes an oscillating sound is made depending upon the characteristic
frequency of the scanner t
(OSC Level/V), or shift the present oscillation frequency (OSC Fre-
quency/kHz) setting position until the sound is not made.
ls from the lock-in amplifie
When using Model 5110 and the signal becomes saturated, the OLVD LED
lights up.
The area in which Asinφ (friction image) becomes white is the one in which
friction is large.
Oscillation level depends upon the scan range.
In this system, if the maximum scan range is scanned, the voltage of 300Vp-p or
400Vp-p will be applied to the scanner. Therefore, there is the following rela-
tionship between the scan range and the voltage applied to the scanner.
Observatio
− =
Vp p
128
(It is difficult to determine an exact Y sensitivity, since you have to execute dis-
tortion correction. However, the Y sensitivity can be estimated all the observa-
tion range/300 V.)
In practice, the output value is a little smaller than the calculated one, because a
low pass filter is contained in the high voltage amplifier.
In lateral modulation FFM, set an excitation voltage to lateral amplitude of sev-
eral nm to several tens of nm of the voltage applied to the scanner. The voltage
amplitude applied to the scanner is 20 times larger than the amplitude input to
the ADY. To obtain exact Y/20, use the optional oscilloscope.
Acos φ
Topography
(Topography
image)
Asin φ
(Friction
image)
hat you use. If it happens, reduce the oscillation level
r do not saturate.
n range
÷
Y Sensitivi
ifier (from 1 mV to 100 nV
÷
ty 15
TMPM5200-2