INFICON Guardian EIES Controller - Manual (Page 95)

4 - 3
IP
N 07
4-
51
7-
P1
D
Guardian Co-Deposition Controller Operating Manual
Figure 4-2 EIES Gas Compensating Sensor 016-601-Gxx
4.2.1 Sensor Position
Location of the sensor within the vacuum system is the most significant factor in
determining EIES system performance. The optical signal generated by the sensor
is often small, especially when the deposition rate for a material is low. The
objective in EIES system installation is to maximize the light output from the sensor,
and deliver as much of that optical signal as possible to the detector(s).
Position the sensor to maximize the material vapor flux passing through it.
The best location is directly above the evaporant source, with the sensor opening
perpendicular to the vapor flux, so the material passes straight through the
opening. When multiple sources are involved, you will have to make a best
estimate of the average flux from all sources.
NOTE: If the sensor is not aligned properly to allow material vapor flux to pass
through it, sensitivity will be reduced. Also, material will accumulate inside
the sensor and sensor life will be shortened.