INFICON MDC-260 Thin Film Deposition Controller - Manual (Page 132)

MDC-260 DEPOSITION CONTROLLER
THEORY OF OPERATION 10-8
Configure Sensors parameters to select which sensors will be used to measure this
material.
Next, scroll down to Calibrate Sensors and press the right arrow key to get to the
Calibrate Sensors screen. Enter the desired calibration thickness and press the
Start key to start the calibration run. The calibration thickness should as thick or
thicker as you’re actual coatings.
Once started, the MDC-260 will condition the source as programmed, open the
source shutter and deposit until the calibration thickness is reached as displayed in
the main thickness display.
Once the calibration run is complete, determine the average film thickness on the
test substrates by using an alternate measurement device such as a surface
profilometer. Enter the measured substrate thickness in the Measured Thickness
field in the Calibration Screen and press Enter. The MDC-260 will calculate the
new tooling factors for all sensors enabled during calibration. The new sensor
tooling factors will be displayed in the NewTlng field in the calibration screen.
The MDC-260 will then ask the user if the new tooling factors should be saved.
10.5.3 ACOUSTIC IMPEDANCE
Establishment of the acoustic impedance requires that the crystal be heavily
loaded. Continue to deposit on the sensor crystal until the crystal health
approaches 50% or until the crystal is approaching the end of its useful life.
Deposit another trial run as above but this time use the manual power mode
instead of the automatic mode. Measure the average film thickness on the test
substrates and this adjust the acoustic impedance parameter up or down to bring
the displayed thickness into agreement with the measured thickness. This
calibrates the acoustic impedance parameter.
The MDC-260 is now fully calibrated for the film in question and should produce
consistent and accurate films.