Conditions
Although Probe for EPMA normally acquires automated samples based on the last unknown sample conditions, the program will support the automatic acquisition of samples under various analytical conditions (if the interface hardware supports it).
There are two different options for analytical conditions, the first is using specified values for kilovolts, beam current and beam size, the second is using a specified string to indicate a column condition that is stored internally in the instrument. In this latter case, because the actual value of the operating voltage (kilovolts) in the column condition string is ambiguous, the user should be sure that the single value fields are also correctly specified based on the column condition string specified.
Note that three different magnifications may be specified. A “default” magnification for the normal state of the instrument (after data or images are acquired), an “analytical” magnification for when acquiring standard, unknown or wavescan data when in Analog Scan mode, and an “imaging” magnification used for image acquisition. Allowable range of magnifications for different platforms is documented here:
Minimum magnification = 40 ‘ JEOL 8900/8200/8500/8x30 (InterfaceType = 2)
Maximum magnification = 300000
Minimum magnification = 63 ‘ SX100/SXFive (InterfaceType = 5)
Maximum magnification = 200000
Therefore, if the column condition option is selected, and the column condition string is specified as "15_keV_30 nA_0_um.PCC" (indicating a column condition at 15 keV), then the user should also be sure that the kilovolts field is correctly specified as 15 keV. Failure to properly specify the kilovolts field when using column condition strings will cause the ZAF or Phi-Rho-Z matrix corrections to be inaccurate.
For accurate documentation purposes it is also preferred that the beam current and beam size fields are also properly specified when using column condition strings. If, as in the above example, the "15_keV_30 nA_0_um.PCC " column condition string also includes a beam current of 30 nA and a beam size of 0 um, then those values should also be specified in the single values fields even though are not actually used in the acquisition procedure. This maintains the accuracy of the documented sample conditions.
By using either the analytical conditions and column condition methods, it is possible to automatically acquire a number of digitized positions using a different kilovolts/beam current/beam size values. This is useful for many purposes, for example, automated thin film analysis, where the acquisition of k-ratios at various operating voltages can improve the analysis considerably.
To utilize this acquisition type, be sure to select the Use Digitized Sample Conditions option before clicking the Run Selected Samples button.