1 related manuals – INFICON SQM-242 Thin Film Deposition Controller Card Operating Manual User Manual
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SQM-242 Operating Manual
The optional SQS-242 software allows multi-layer deposition recipes, graphics,
flexible PLC-based digital I/O and RS-232/Ethernet external control.
The SQM-242 card is a PID loop process controller designed for use primarily in
physical vapor deposition. The SQM-242 card monitors and/or controls the rate
and thickness of thin film depositions. The SQM-242 reads frequency from an
in-vacuum 1 to 10 MHz quartz crystal driven by a small external oscillator module.
The oscillator module uses the in-vacuum crystal as the feedback element of an IC
oscillator circuit to amplify the crystal signal to about 0.75 volts peak to peak. The
SQM-242 card supplies 5 V (dc) to the oscillator module, and reads the module's
frequency output signal on a single BNC cable. On the SQM-242, a 200 MHz
reference oscillator sets a known measurement period. By counting the input
transitions during the measurement period, a frequency is calculated.
Deposition rate and thickness are inferred from the frequency change induced by
mass added to a quartz crystal. This technique positions sensors in the path
between, or to the side of, the target substrate and the source of vaporized
material. The sensor incorporates an exposed oscillating quartz crystal whose
frequency decreases as material accumulates. The change in frequency provides
information to determine rate and thickness and to continually control the
evaporation power source. With user supplied time, thickness and power limits and
with desired rates and material characteristics, the SQM-242 card is capable of
automatically controlling the process in a precise and repeatable manner. User
interaction is accomplished via the front panel or serial communications and
consists of selection or entry of parameters to define the process.
When reading this SQM-242 Manual, please pay particular attention to the
NOTES, CAUTIONS, and WARNINGS found throughout the text. The Notes,
Cautions, and Warnings are defined in
.
1.1.1 Related Manuals
Sensors are covered in separate manuals. PDF files of these manuals are
contained in the 074-5000-G1 CD, part of the Ship Kit.
074-154 - Bakeable Sensor
074-156 - Front Load Sensor, Single/Dual
074-157 - Sputtering Sensor
147-800 - Cool Drawer Sensor, Single/Dual