INFICON XTC/3 Thin Film Deposition Controller Operating Manual User Manual

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XTC/3 Operating Manual

Table 6-2 Troubleshooting transducers/sensors

SYMPTOM

CAUSE

REMEDY

1. large jumps of thickness
reading during deposition

a. mode hopping due to
defective crystal

a. replace crystal

b. stress causes film to peel
from crystal surface

b. replace crystal

c. particulate or "spatter" from
molten source striking crystal

c. thermally condition the
source thoroughly before
deposition, use a shutter to
protect the crystal during
source conditioning

d. scratches or foreign
particles on the crystal holder
seating surface (improper
crystal seating)

d. clean and polish the crystal
seating surface on the crystal
holder

e. small pieces of material fell
on crystal (for crystal facing up
sputtering situation)

e. check the crystal surface
and blow it off with clean air

f. small pieces of magnetic
material being attracted by the
sensor magnet and contacting
the crystal (sputtering sensor
head)

f. check the sensor cover's
aperture and remove any
foreign material that may be
restricting full crystal coverage

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.