Lake Shore Cryotronics CRX-6.5K, Руководство пользователя

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102 CHAPTER 4: Basic Operation
Model CRX-6.5K Probe Station
7. Focus must be adjusted repeatedly as the image is zoomed in and further refined.
It is necessary to focus clearly on the sample surface in order to properly
land probes.
8. The shaft collar is set at Lake Shore for relatively thin samples. If thicker samples
are outside of the focal range of the microscope, the shaft collar should be raised
(section 6.3.4.5).
The camera has a specified working distance, which is the distance from the sample
to the lens. Raising or lowering the microscope outside this working distance will not
improve magnification or resolution.
4.6.2 Landing the Probe Follow this procedure to manipulate a probe to the sample and make contact.
The sample stage and probe arms should be at a steady temperature before landing a
probe. Failure to do so will potentially cause damage to the probe tip or scratch the
sample surface.
1. Swing the microscope away from the viewport.
2. Use the z-axis micrometers to raise all probes 3 to 4 mm above the sample. Fail-
ure to do so will potentially cause damage to the probe tip or scratch the
sample surface.
3. Position the probe tips over the sample or landing pads using the x-axis hand dial
and y-axis micrometer.
4. Swing the microscope over the viewport.
5. Adjust the microscope to fill the monitor with the sample image and focus at the
height of the landing pads or landing surface.
6. Use the z-axis micrometer to move the probe tip up and down until the tip begins
to come into focus. At this point the tip is only 30 µm to 60 µm away from
the sample.
7. Continue lowering the probe slowly, stopping to position it as needed so the tip
lands on the outside edge of the landing pad.
8. Once it lands on the pad (which is indicated by a forward movement, known as
skating), continue lowering it until it skates on the pad by a consistent amount. A
typical amount of skating is 20 µm to 25 µm, which is roughly the same as two
scale graduations on the z-axis hand dial.
9. The desired position of the probes with respect to the edge of the pads and the
desired amount of skating should be determined and used as a lab standard to
ensure consistent results.
Raise all probes 3 mm to 4 mm above the sample before changing temperature or vacuum.