INFICON SQC-310 Thin Film Deposition Controller User Manual
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SQC-310 Operating Manual
Verify that the sensors, oscillator and cabling are connected as shown in
. Assure that a good ground connection has been made to the
SQC-310 chassis.
Replace the quartz crystal. Crystals sometimes fail unexpectedly, or exhibit erratic
frequency shifts before total failure. Depending on the material being deposited,
crystals may fail well before the typical 5 MHz value. If you find that crystals
consistently fail early, you may want to set Min Frequency in the System Menu to
a value higher than 5 MHz.
In the System Menu, assure that Simulate Mode is OFF, and Frequency Min/Max
are set properly for your crystals (typically Freq Min=5.0 MHz, Freq Max=6.0 MHz).
Some manufacturer's crystals exceed 6 MHz when new. Setting Frequency Max to
6.1 MHz will correct that problem, with no bearing on instrument accuracy.
Press Sensor Info and assure that the proper sensors are enabled. While not
depositing, observe the % Life display for each active sensor. The value should be
stable, between 20% and 100%.
If the % Life reading is zero or unstable: Recheck the wiring from the sensor to the
SQC-310, and verify that the SQC-310 is properly grounded. Also check that the
crystal is seated properly in the sensor head. You can swap the sensor to the other
SQC-310 input. If both SQC-310 inputs show zero or unstable readings, the
problem is almost certainly a wiring or sensor problem.
If the % Life is less than 50%: Replace the crystal and assure that % Life is near
100%, very stable. If % Life is not near 100%, check the Frequency Min/Max limits.
If the problem is not corrected: Referring to
, disconnect the 6” M/F BNC
cable from the external oscillator module. A 5.5 MHz test crystal and BNC barrel
adapter is supplied with each oscillator kit. Attach the test crystal to the oscillator
Sensor connector. The display should read about 5.5 MHz, very stable. If not,
contact INFICON technical support.
When the frequency reading is stable, reconnect the source supply and sensor.
Start the deposition process in Manual mode with 0% power. The % Life readings
should remain stable.
Slowly raise the % Power until a rate reading is displayed above the graph. As
material is deposited on the crystal, the % Life reading should remain stable, or
drop slowly and consistently. If not, check your source supply for erratic output.
Also assure that the sensor is not too close to the source (particularly in sputtering).
Incorrect Rate or Thickness Measurement
First, complete the procedures in the beginning of
to assure reliable
sensor operation.
Set the Xtal Tooling as described in
section 3.11, System Menu, on page 3-19
.
Incorrect Xtal Tooling values will cause consistently low or high rate/thickness
values for every material.