7.9.1 Selecting recommended operating modes
Fig. 19:
Default parameters of the Ion Source Tuning program of the Quadera software
Fig. 20:
Optimized ion source parameters for spectrum with nitrogen and oxygen, using a
CB-IQ as an example
Using "Ion Source Tuning"
The "
Mass Mode: SCAN-N
" is highly suitable for optimization tasks, as it shows the unfiltered peaks.
1. Use "
Autorange Mode
":
AUTO
.
2. Select a small "
Width
" (
5 – 10 u
).
3. Set "
First
" to a value where the peaks of interest are in the middle of the displayed range.
– The logarithmic 3-decade visualization of the ion current makes it possible to clearly see the
resolution, the peak shape and peak height. Depending on the aim of the optimization, a line-
ar or logarithmic visualization across e.g. 6 decades can be more advantageous.
4. For the optimization, first use "
Detector Type: FARADAY
" and then "
SEM
".
5. Set the deflection voltage at "
Inner Deflection
"
8)
and readjust "
Field Axis
" slightly, if necessary.
6. Prior to the optimization, let the device warm up for 30 minutes with the emission switched on.
– Wait for the initial outgassing process.
8)
Only in the case of detector type SEM
Operation
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