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XTC/3 Operating Manual
NOTE:
Crystal life is highly dependent on process conditions of rate, power radiated
from source, location, material, and residual gas composition.
3. crystal does not oscillate
or oscillates intermittently
(both in vacuum and in air)
a. intermittent or poor
electrical contact (contacts
oxidized)
a. use an ohm meter or
DVM to check electrical
continuity, clean contacts
b. leaf springs have lost
retentivity (ceramic retainer,
center insulator)
b. bend leaves to
approximately 45°
c. RF interference from
sputtering power supply
c. verify earth ground, use
ground strap adequate for
RF ground, change location
of XTC/3 and oscillator
cabling away from RF
power lines, connect XTC/3
to a different power line
d. cables/oscillator not
connected, or connected to
wrong sensor input
d. verify proper
connections, and inputs
relative to programmed
sensor parameter
4. crystal oscillates in
vacuum but stops
oscillation after open to air
a. crystal was near the end
of its life; opening to air
causes film oxidation which
increases film stress
a. replace crystal
b. excessive moisture
accumulates on the crystal
b. turn off cooling water to
sensor prior to venting, flow
warm water through sensor
while chamber is open
Table 6-2 Troubleshooting transducers/sensors (continued)
SYMPTOM
CAUSE
REMEDY