Page 8 - Shimadzu EPMA-8050G
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Unprecedented Spatial Resolution                                                                                   Large Beam Current Enabling


                                                                                                                                        Ultra-High-Sensitivity Analysis



                     The system offers the ultimate in secondary-electron image resolution under the beam current                       In SEM and EPMA with the FE type, the uniquely large beam current (up to 3  A with a 30 kV
                     conditions used for analysis. (With a 10 kV accelerating voltage, 20 nm at 10 nA / 50 nm at 100                    accelerating voltage) dramatically enhances the detection sensitivity for ultra trace elements. This
                     nA / 150 nm at 1  A). The results are very clear in comparison to a conventional electron gun                      enables ultra-trace component imaging in element mapping.
                     (CeB6, tungsten).                                                                                                  In addition, there is no need to replace the objective aperture across the entire beam current
                     The same resolution image can be obtained with a dramatically larger beam current than with a                      range, so the analysis process can be fully automated, with no concerns about axis offset.
                     conventional electron gun, so extremely high-sensitivity X-ray analysis can be performed.                          These three images show the results* of a mapping analysis of approx. 1 % Si in stainless steel,
                     A further point of interest is SEM imaging with a 1  A beam current. Only the EPMA-8050G                           using different beam currents. The roughness decreases as the beam current increases, enabling
                     provides a beam current of at least 1  A, and moreover, finely focuses the beam to this point.                     the areas containing Si to be precisely identified.
                                                                                                                                        * In all of the measurements, the accelerating voltage was 10 kV and the sampling interval was 50 msec. The measurements required approx. 1 hour.

                                    FE                         CeB6                      Tungsten






                  10nA

                                                                                                                                                          100nA







                                                                                                                                                                  Si
                 100nA                                                                                                                                                                             5µm








                                                                                                                                                          500nA

                   1µA                               This current cannot be set.  This current cannot be set.




                                                                                                                                                                  Si
                                                                                                                                                                                                   5µm
                                      Comparison of Electron Gun Beam Characteristics (10 kV accelerating voltage)







                                               EPMA-8050G           Irradiation Current  Resolution                                                        1.5µA
                                                                          10 nA       20 nm
                                      Resolution at each current condition  100 nA    50 nm
                                        (Acceleration voltage is 10 kV)
                                                                        1000 nA       150 nm
                                     *The resolution described is the secondary electron resolution under each condition.
                                     *Switching and adjustment of the objective aperture are not necessary.
                                                                                                                                                                  Si
                                                                                                                                                                                                   5µm
                                                                                                                                                                                                                        EPMA-8050G
                                                                                                                                                                                                                         Electron Probe Microanalyzer
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