INFICON Cygnus Thin Film Deposition Controller - Manual (Page 180)

8 - 14
IP
N 07
4-
37
9-
P1
K
Cygnus Operating Manual
2. crystal ceases to oscillate
during deposition before it
reaches its "normal" life a. crystal struck by
particulate or "spatter" from
molten source a. thermally condition the
source thoroughly before
deposition, use a shutter to
protect the crystal during
source conditioning
b. material on crystal holder
partially masking crystal
cover aperture b. clean crystal holder
c. existence of electrical
short or open condition c.using an ohm meter or
DVM, check for electrical
continuity in the sensor
cable, connector, contact
springs, connecting wire
inside sensor, and
feedthroughs
d. check for thermally
induced electrical short or
open condition d. see C above
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 instrument and oscillator
cabling away from RF
power lines, connect
instrument 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
Table 8-2 Troubleshooting Transducers/Sensors (continued)
SYMPTOM CAUSE REMEDY