3 – 3
RSH-600 Operating Manual
Thermal instability: large
changes in thickness reading
during source warm-up
(usually causes thickness
reading to decrease) and
after the termination of
deposition (usually causes
thickness reading to
increase)
Inadequate cooling
water/cooling water
temperature too high
Check cooling water flow
rate, be certain that cooling
water temperature is less
than 30°C
Excessive heat input to the
crystal
If heat is due to radiation
from the evaporation source,
move sensor further away
from source and use
sputtering crystals for better
thermal stability
Crystal not seated properly in
holder
Clean or polish the crystal
seating surface on the crystal
holder
Poor thickness
reproducibility
Variable source flux
distribution
Move sensor to a more
central location to reliably
sample evaporant, ensure
constant relative pool height
of melt, avoid tunneling into
the melt
Sweep, dither, or position
where the electron beam
strikes the melt has been
changed since the last
deposition
Maintain consistent source
distribution by maintaining
consistent sweep
frequencies, sweep
amplitude and electron beam
position settings
Material does not adhere to
the crystal
Make certain the crystal
surface is clean; avoid
touching crystal with fingers,
make use of an intermediate
adhesion layer
Table 3-1 General troubleshooting (continued)
SYMPTOM
CAUSE
REMEDY