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CHAPTER 4:
Basic Operation
Model CRX-6.5K Probe Station
4.3 Sample
Exchange
This section covers the steps required to load and unload a sample.
Wear nitrile gloves when handling anything inside the probe station. Hand oils will
contaminate the surfaces, resulting in poor vacuum and thermal performance.
4.3.1 Opening the
Vacuum Chamber and
Radiation Shield
The probe station should always be stored with the system under vacuum to help
prevent contamination and oxidation. This section is written assuming the chamber
is under vacuum, the vacuum pump is turned off, and the vacuum isolation valve is
closed. Follow this procedure to open the vacuum chamber and radiation shield.
1.
Raise
each probe 3 mm to 4 mm above the sample holder using the z-axis
micrometers.
2.
Center
all probes using the y-axis micrometers.
3.
Retract
all probes away from the sample stage using the x-axis hand dials. This
will provide maximum access to the sample stage.
4.
Recommended:
connect a tank of dry, inert gas such as nitrogen or argon to the
purge valve and follow the instructions for purging the vacuum chamber
(section 4.4.4). Input 6.9 kPa to 13.8 kPa (1 to 2 psi) into the chamber during the
remainder of this procedure.
Alternate:
to release the vacuum to atmosphere, slowly open the purge valve by
turning the hand knob on the top of the valve counterclockwise.
5. Using the 2.5 mm hex driver, unlock the four captive quarter-turn fasteners on
the vacuum chamber lid.
6. Pull up gently on the lid to remove it. A light bump may be required to release the
o-ring seal if the chamber was closed for a long time.
7. Place the vacuum chamber lid in a safe place where it will not get scratched or
contaminated.
8. Using the 2.5 mm hex driver, loosen the eight M3 screws from the outer edge of
the radiation shield lid. The screws are captive and stay with the radiation
shield lid.
9. Place the radiation shield lid with the vacuum chamber lid. Bumpers are built
into the radiation shield lid for it to rest on.
FIGURE 4-3
Left: Vacuum isolation valve on the probe station;
Right: Probe station vacuum chamber lid removal