Design and Testing of a Quadrupole/Octupole C3/C5 Aberration Corrector
نویسنده
چکیده
The ideal location for an aberration corrector in an electron-optical column is exactly at the place where the aberration to be corrected is introduced. In practice, this of course cannot be achieved. The resultant separation between where an aberration is introduced and where it is removed produces combination aberrations for all aberrations of higher than first order. A case of particular importance to electron optics is third order aberration (Cs) correctors. For which a physical separation between the objective lens, which introduces the aberration and the corrector, which removes it, results in fifth order spherical aberration (C5,0).
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Optimized Quadrupole-Octupole C3/C5 Aberration Corrector for STEM
The ideal location for an aberration corrector in an electron-optical column is at the place where the aberration is introduced. In practice, this of course typically cannot be achieved. The resultant separation between where an aberration is introduced and where it is removed produces combination aberrations for all aberrations of higher than first order. In the case of third-order aberration ...
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