INFICON SQM-242 Thin Film Deposition Controller Card Operating Manual - Manual (Page 36)

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SQM-242 Operating Manual
Sensors Frame . . . . . . . . . . . . . . . . Settings in this frame control a sensor’s
calculation of rate and thickness. They also
allow a sensor to be assigned as a Final
Thickness monitor, independent of any
output control assignment.
Density . . . . . . . . . . . . . . . . . . . . . . The density of the material measured by this
quartz sensor, in grams per cubic centimeter.
Material density can be found in
Table A-1
and numerous handbooks.
Z-Ratio. . . . . . . . . . . . . . . . . . . . . . . Z-Ratio compensates for the mechanical
stress a material causes to the quartz crystal.
Z-Ratio has an effect only during the last 70%
of crystal life. If you cannot find the Z-Ratio of
a material, set the value to 1 and change
crystals when the crystal Life approaches
70%. See
Table A-1 for known values of
some materials.
Tooling . . . . . . . . . . . . . . . . . . . . . . Adjusts for measured deposition rates that
differ from the actual substrate deposition
rate. If the sensor sees only 50% of the
substrate rate, set the value to 200. This
multiplies the sensor reading by 2. Use
Figure 3-6 as a general guard for
approximating tooling factor.
Figure 3-6 Tooling Factor Approximation
Substrate
Substrate
Tooling
Over 100%
Tooling
Under 100%