Correction of parasitic aberrations of hexapole corrector using differential algebra method

0508150 - ÚPT 2020 RIV NL eng J - Journal Article
Radlička, Tomáš
Correction of parasitic aberrations of hexapole corrector using differential algebra method.
Ultramicroscopy. Roč. 204, SEP (2019), s. 81-90. ISSN 0304-3991. E-ISSN 1879-2723
R&D Projects: GA TA ČR(CZ) TE01020118; GA MŠMT(CZ) LO1212; GA MŠMT ED0017/01/01
Institutional support: RVO:68081731
Keywords : electron optics * correctors * aberrations * differential algebra method
OECD category: Electrical and electronic engineering
Impact factor: 2.452, year: 2019
Method of publishing: Limited access
https://www.sciencedirect.com/science/article/pii/S030439911930035X?via%3Dihub

We demonstrate an application of the differential algebraic method in optimization of a hexapole corrector of spherical aberration for the transmission regime of the standard scanning electron microscope. We introduce the method by visualization of the effect of all correcting elements to illustrate the principle of the corrector. Special interest is given to parasitic aberrations and their correction using additional deflectors before and inside the corrector. They can alter the off-axial position and tilt of the beam in the hexapoles. The critical values of the parasitic aberration coefficients are calculated using a wave-optical method, which determines the stability of the deflection system, the lens doublet, and the hexapoles. The derived properties of the parasitic aberrations are used in an alignment procedure of the system with the corrector.
Permanent Link: http://hdl.handle.net/11104/0299133