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The innovative GEMINI® column concept provides superior beam brightness with ultra high resolution over the complete voltage range together with high probe currents for analytical applications.
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Operating principle of the GEMINI® field emission column.
U1 - extractor voltage at first anode
U0 - accelerator voltage at second anode
UB - booster voltage |
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A beam booster is an integral part of the GEMINI® electron optical column. The beam booster always maintains a high beam energy throughout the entire column, regardless of the electron beam energy selected by the operator. Only after passing through the scanning system is the electron beam decelerated to its selected landing energy. The electron beam path has been designed to eliminate cross over of beam electrons between source and specimen.
Furthermore, the high beam energy throughout the column ensures that the GEMINI® column is extremely well protected against stray magnetic fields, even when operated at very low voltages. The tolerable stray magnetic field limit is therefore independent of the selected voltages. An electromagnetic, multi-hole aperture changer is incorporated close to the electron source, in combination with a magnetic field lens to select the optimum beam aperture angle and to tune the probe current. The combination of the high beam energy and cross-over free electron beam path also minimise the statistical Coulomb interactions between beam electrons, which tend to reduce the brightness and hence the resolution limit of the microscope. As a result, the GEMINI® column always provides optimum beam brightness, especially when needed at the lowest electron probe energies. | |
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SEM Microscopes
CrossBeam® Workstations (FIB-SEM) |