Inficon IC6, Operating Manual

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IC6 Operating Manual
The Rate Filter Time may be used for enhanced resolution. If a source has a
long time constant, rate may be taken as constant over longer intervals
Averaging provides an opportunity to reduce rate noise. Depending on the
source of the noise, averaging can improve rate resolution:
 If the noise is crystal frequency resolution limited—the thickness change
over one second provides ten times the thickness change vs. the thickness
change measured over a tenth of a second. A one second averaging
interval will improve rate resolution by 10 times.
 If the sensor noise is random, then RMS reduction of rate noise is provided
by the square root of the number of point’s averaged (example a 10 point
average provides a factor of 3.1 noise reduction).
The selection of the appropriate Rate Filter Time value will be dependent on the
characteristics of the source. The default value is One Tenth.
NOTE: To obtain rate display resolution of 0.001 Å/s for the range of 0.000 to
9.999 Å/s, set the Rate Filter Time to 10 s or greater.
TIME POWER AVERAGING TIME . 0 to 30 min (default = 0)
This parameter value determines the amount of time used in calculating the
average rate and average power for use in Time Power and Non-Deposit Hold
states if a crystal fails. It also determines the duration of the RateWatcher
Sample period (see
RateWatcher™ Sample and Hold Feature on page 5-19 ).
When the Averaging Time parameter value is 0, then a 2.5 second average,
ignoring the most recent 0.5 second, is the averaging interval.
The status message ABBR(EVIATED) AVERAGE is generated if the averaging
interval has not been reached, but there was at least a complete whole minute
of data to average.
The status message NO or NEG AVERAGE is generated if a crystal fail
occurred within the first minute of control with Averaging Time set >0. This error
also occurs if there is a crystal fail during the first 2.5 seconds of control with
the Averaging TIme = 0. (There are also remote communication commands to
get and set the average rate and average power values.)
ION ASSIST DEPOSIT . . . . . . . . . . No (0), Yes (1).
Sets the logic condition to True if Yes (1) is selected and the Deposit state is
entered. Default is No (0).
ON FINAL THICKNESS . . . . . . . . . . Continue (0), Post-Dep (1), NonDepCont (2).
Selects the state to enter after reaching Final Thickness. Standard processing
will continue with Post-Deposit (1), the default setting. In special cases,
Non-Dep(osit)Cont(rol) (2) may be appropriate. In this state, the rate is
controlled but thickness is not incremented and the source shutter relay is not
active. Continue (0) ignores reaching Final Thickness but the logic condition is
set to True.