JEOL JSPM-5200 Instructions Manual page 202

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