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

Page 177

6 - 15

XTC/3 Operating Manual

6. poor thickness
reproducibility

a. variable source flux
distribution

a. move sensor to a more
central location to reliably
sample evaporant, ensure
constant relative pool height of
melt, avoid tunneling into the
melt

b. sweep, dither, or position
where the electron beam
strikes the melt has been
changed since the last
deposition

b. maintain consistent source
distribution by maintaining
consistent sweep frequencies,
sweep amplitude and electron
beam position settings

c. material does not adhere to
the crystal

c. make certain the crystal
surface is clean; avoid
touching crystal with fingers,
make use of an intermediate
adhesion layer

d. cyclic change in rate

d. make certain source's
sweep frequency is not
"beating" with XTC/3
measurement frequency

7. large drift in thickness
(greater than 200 A for a
density of 5.00 g/cc) after
termination of sputtering

a. crystal heating due to poor
thermal contact

a. clean or polish the crystal
seating surface on the crystal
holder

b. external magnetic field
interfering with the sensor's
magnetic field (sputtering
sensor)

b. rotate sensor magnet to
proper orientation with external
magnetic field, refer to the
sputtering sensor manual (CD
PN 074-5000)

c. sensor magnet cracked or
demagnetized (sputtering
sensor)

c. check sensor magnetic field
strength, the maximum field at
the center of the aperture
should be 700 gauss or greater

Table 6-2 Troubleshooting transducers/sensors (continued)

SYMPTOM

CAUSE

REMEDY