INFICON XTM/2 Thin Film Deposition Monitor - Manual (Page 52)

2 - 26
IP
N 07
4-
18
6S
XTM/2 Operating Manual
2.7.6 Contamination Detection
The measurement of a crystal’s mass loss or gain is enhanced by utilizing the
averaging and displayed units configuration switches, refer to
section 2.5.2 on
page 2-15 . These may be used to directly display the mass change in
micrograms (µgm) or milligrams (mg). In addition, the displayed resolution may
be enhanced by increasing the measurement time averaging to as long as 16
seconds. This technique reduces the relative noise in the ratio of the square
root of the sample time.
The limiting problem will most probably be either temperature changes of the
monitor crystal or the instrument’s reference crystal. Careful temperature
control can minimize these effects.