CRYSTALSIX - Schoonover, Inc.

CrystalSix Sensor Operating Manual
Table 4-1 Troubleshooting (continued)
IPN 074-155G
Symptom Cause Remedy
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)
Poor thickness
reproducibility
Crystal not properly
seated.
Excessive heat input to
the crystal.
No cooling water.
Poor thermal transfer
from water tube to body.
Erratic source emission
characteristics.
Check and clean crystal
seating surface of the
crystal holder.
If heat is due to radiation
from the evaporation
source, move sensor
further away from source
and use sputtering
crystals for better thermal
stablity.
Check cooling water flow
rate. Flow rate should be
minimum of 150-200
c/min @ 30 °C max.
Use a new water tube
whenever the clamping
assembly has been
removed from the body. If
a new water tube is not
available, use a single
layer of common
aluminum foil between
the cooling tube and the
sensor body, if your
process allows.
Move sensor to a
different location; check
the evaporation source
for proper operating
conditions; insure
relatively constant pool
height and avoid
tunneling into the melt.
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