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MEASUREMENT OPERATION
TMPM5200-2
5-139
hen applying an optionally designated bias voltage while keeping the
distance betw
and data averaging at designated points on the specimen can also be obtained from the
and an image is created at each pixel during tip scanning, so there is no influence of
spec
perfe
■
CITS image observation
A CITS (Current Imaging Tunneling Spectroscopy) image is a tunneling-current image
produced w
een the tip and the specimen surface (determined by the topographic-image
observation conditions such as tunneling current and bias voltage) constant. I-V curves
image captured in the CITS menu. In the case of CITS, unlike STS, I-V data is measured
imen drift or hysteresis so that the I-V curve at an arbitrary point of the image
ctly corresponds to the image points.
Tip
I-V cur ve is measured at ever y pixel
128 points
128 points
I-V measurement
15 points
standard)
One method of determining the bias voltage is as follows.
Select a point where the image contrast varies greatly on an STM image and measure an
I-V curve at that point once; then select the bias voltage of the position where the I-V
curve varies
CITS
Voltage and High Voltage are the same as
Ob
1.
Select the CITS radio button at the left bottom of the STM tab window.
greatly.
measurement parameters such as Low
those set in the I-V Parameters.
serve a CITS image using the following procedure.
