Raith 150, Руководство по эксплуатации системы

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5.4 Sample holders
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5.3.2 Nitrogen and air
Monitoring N
2
, used for venting, and compressed air, used for valves
and pneumatic bellows, pressure regulators:
•
The Nitrogen venting pressure should not exceed 0.3 bar (5 psi).
•
The compressed air pressure should be set between 7 – 8 bar (100
– 120 psi).
5.3.3 Isolation
Checking system for sources of vibration coupling to SEM:
•
If you suspect that the vibrations are affecting your imaging,
check the cables and hoses going into the system. In particular,
make sure the metal vacuum line is not touching anything
between the white isolation block and the turbo pump. The metal
hose is flexible, but do not over bend it.
•
Also, ensure that the bellows of the internal isolation table are
inflated to about 5 mm, and that the chamber is floating.
•
If a separate, external isolation platform is used, check also this
for correct inflation and functionality.
5.4 Sample holders
The most critical sample holder is the electrostatic chuck which will
be described separately. The other sample holders are less critical.
Please pay special attention when pre-leveling the holders using the
sapphire insets. Pre-leveling is described in a separate manual.
Contact Raith for information on spare parts.
5.4.1 Universal sample holder, mask holder, wafer
carrier
Periodically clean the sample holders in an ultrasonic bath. Clean as
often as necessary. The sample surface must be kept clean. Avoid
using conductive paste/paint products on the surface since any
material on the surface will affect how flat the sample pieces are held.
For the same reason, avoid using metal tweezers since they can easily
scratch the top surface.
The under-side of the sample holder must also be clean. The titanium
or sapphire inserts that make contact with the posts on the top the
stage must be kept clean since this effects positioning repeatability of
the holder. The under-side of the sample holder also makes contact to
a lead on the top of the stage for measuring the beam current from the