INFICON TM-400 Thin Film Deposition Monitor - Manual (Page 59)

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TM-350/400 Operating Manual
Chapter 9
Establishing The Deposition Parameters
9.1 Introduction
The following is a guide to establishing the deposition parameters. Valid reasons
may occur to deviate from the recommendations and these reasons of course
would take precedence.
9.2 Tooling Factor
The Tooling Factor parameter compensates for geometric factors in the deposition
system, which result in a difference between the deposition rate on the substrates
and the rate on the sensing crystal. The TM-350 has only one tooling parameter for
its one sensor input. The TM-400 has two tooling parameters, one for each sensor.
Since they are in different locations, they most likely will require different values.
The tooling is entered in percent units and 100% corresponds to equal rates at the
substrate and at the sensing crystal. For initial approximation the tooling factor can
be calculated using the following equation:
[1]
where:
dc = Distance from the source to the crystal
ds = Distance from the source to the substrate.
Equation 1 assumes that the angle from normal between the source and sensor
and the source and substrate is zero. To account for the angle of the crystal and
the substrate, use equation 2:
[2]
where:
dc = Distance from the source to the crystal
ds = Distance from the source to the substrate.
φ c = The angle of the crystal off of normal from the source.
φ s = The angle of the substrate off of normal from the source.
This equation assumes the crystal face is perpendicular to the source.
Empirical calibration of the tooling factor is described in
section 9.6.2 on page
9-3 .
Tooling%
dc
ds
------
⎝ ⎠
⎛ ⎞
2
100 ⋅
=
Tooling%
dc
ds
------
⎝ ⎠
⎛ ⎞
2
100
φ cos s
φ cos c
---------------
⎝ ⎠
⎛ ⎞
⋅ ⋅
=