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PIPS II Owners Manual and Users Guide
With the ion guns on at 5 kV, 5 degrees, and dual beam modulation a bulk
sample (e.g., Ta) mounted in a clamp-type DuoPost will increase in
temperature by about 25-50 °C. The temperature of a thin specimen will
increase more, depending on the thermal conductivity of the sample, the
thickness of the sample, and the power density of the ion beam. In general,
lower energy and a more defocused (broader) beam will result in a smaller
temperature rise during milling.
The temperature measured at the cold conductor is typically about 50-75 °C
cooler than the temperature at the sample. In addition, there is a time delay of
about fifteen minutes between a change in cold conductor temperature and the
corresponding change in sample temperature. For instance, if the stage is
lowered and you fill the dewar with liquid nitrogen, the conductor will reach -
100 °C about fifteen minutes before the sample.
Figure 7-3 Sample and cold conductor temperature over time.
Stage was lowered at zero minutes. Dewar was filled and cold prior to this test.
NOTE:
When the stage is raised into the airlock, the temperature of the
sample post will typically increase to nearly room temperature in fifteen
minutes.
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200
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150
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100
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50
0
50
0
15
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60
Tem
p
e
ra
tur
e
(de
g
C)
Time
(min)
PIPS
II
Cold
Stage
Lower
while
dewar
is
cold
Cold
Finger
Sample
