One can now specify multiple apertures for JEOL instruments in the Probewin.ini file. This is so that one can switch apertures and still be able to set the beam current automatically from the PFE software.
However, each JEOL instrument has slightly different conventions for the beam current parameters due to changes in the way that JEOL defines the condenser lens values for each successive EPMA model (8900/8200/8x30).
For example, with the JEOL 8900, the condenser lens parameters vary from a low condenser value (high beam current) to a high condenser value (low beam current) and the condenser lens values displayed in the JEOL software reflects that convention. The beam calibration parameters should look something like this (note that a semi-colon indicates a comment follows):
[pending]
However, the JEOL 8200 instrument is different in that the condenser lens values are internally the same as the 8900, but the displayed values in the JEOL software are "inverted" in that they show a low condenser lens parameter for low beam currents and a high condenser lens value for high beam currents like this:
; Lens ranges for 8x00 instruments:
; Coarse CC 0-95 for 8900 and 8200, CC 0-85 and 16-101 for 8500 CC 36-85 for 8530
; Fine CF 0-255 for 8900, 0-511 for all other models
; condenser lens settings for 8900 and 8200 are internally the same but display on 8200 and 8500 is reversed
; To convert 8200 to internal units take displayed value and set CC = 95-x and CF = 511-x
; Typical 8900 for aperture 1 are low=20 med=35 high=56 for 225nA 25nA and 1 nA
; Typical 8200 for aperture 2 are low=3 med=21 high=44 for 225nA 25nA and 1 nA
; 3-10-07 WU8200 bias affects these settings, today @15kv low=10 med=28, high=49
; WU8200 aperture 1 15kv low=4 med=23 high=46 for 225nA 25nA and 1 nA
; WU8200 aperture 2 15kv low=0 med=20 high=43 for 225nA 125nA 25nA and 1 nA (6 for 125nA)
; WU8200 aperture 3 15kv low=2 med=16 high=40 for 125nA 25nA and 1 nA
; WU8200 aperture 4 15kv low=4 med=19 high=32 for 29nA 5nA and 1 nA
; NOTE All calibrations made with CF set to midrange (128 for 8900 and 255 for all others)
; CC is then set to give probe current closest to target values
JeolCondenserCoarseCalibrationMode= 1
JeolCondenserNumberOfApertures=2 ; Number of apertures for which CL settings to be read
JeolCoarseCondenserCalibrationDelay=0.5 ; Delay in seconds between coarse CL settings for calibration
JeolCondenserCoarseCalibrationSettingLow=8,3 ; High cl current coarse range for search ~several hundred nA
JeolCondenserCoarseCalibrationSettingMedium=25,21 ; Middle cl current coare range for search ~25nA
JeolCondenserCoarseCalibrationSettingHigh=47,44 ; Low cl current coarse range for search ~ 1nA
JeolCondenserFineCalibrationSetting=255 ; Middle of fine cl range is 128 for 8900 and 256 for 8200
; high probe current setting -- target value is ~225nA
JeolCondenserCoarseCalibrationBeamLow=286.35,265.85 ; last modified 12/19/2011 11:45:26 AM
; medium probe current setting -- target value is normal working probe current ~25nA
JeolCondenserCoarseCalibrationBeamMedium=34.75,29.45 ; last modified 12/19/2011 11:45:26 AM
; low probe current setting corresponding to high CL -- target value is ~ 1nA
JeolCondenserCoarseCalibrationBeamHigh=1.4062,1.0827 ; last modified 12/19/2011 11:45:26 AM
On the 8x30 (8230/8530) JEOL instruments, the internal and displayed condenser lens parameters are the same but both are inverted from the traditional sense as seen in the 8900. The beam current calibration values for the 8230/8530 look like this:
JeolCondenserCoarseCalibrationSettingLow=65,71,78,80 ; CC high current ~several hundred nA
JeolCondenserCoarseCalibrationSettingMedium=40,57,65,75 ; CC medium current ~25nA
JeolCondenserCoarseCalibrationSettingHigh=36,43,36,36 ; CC low current ~ 1nA
JeolCondenserCoarseCalibrationBeamLow=609.9,107.71,111.71,37.85 ; low probe current setting, last modified 7/31/2013 11:14:49 AM
JeolCondenserCoarseCalibrationBeamMedium=13.836,10.2,10.354,14.09 ; medium probe current setting, last modified 7/31/2013 11:14:49 AM
JeolCondenserCoarseCalibrationBeamHigh=7.491,1.1001,.10031,.023 ; high probe current setting corresponding to high CL, last modified 7/31/2013 11:14:49 AM
JeolCondenserFineCalibrationSetting=255 ; middle of fine cl range is 255 for 8530
JeolCondenserCoarseCalibrationMode= 1
JeolCondenserNumberOfApertures=4 ; number of sets of probe current calibration data expected
JeolCoarseCondenserCalibrationDelay=1.0
When you edit the Probewin.ini file to add apertures or adjust the condenser settings, it is usually easiest to edit the JeolCondenserCoarseCalibrationSettingLow, JeolCondenserCoarseCalibrationSettingMedium, JeolCondenserCoarseCalibrationSettingHigh values and then calibrate the actual beam currents using the Calibrate Set Beam Current button in the Analytical Conditions dialog as seen here:
http://probesoftware.com/smf/index.php?topic=113.msg409#msg409
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