Axial geometrical aberration correction up to 5th order with N-SYLC

•Novel corrector for 5th order geometrical aberrations is proposed.•The corrector is a superposition of sextupole, octupole and dodecapole fields.•Each multipole field is generated by N-SYLC.•The corrector is free of magnetic material unlike conventional correctors. We present N-SYLC (N-fold symmetric line currents) models to correct 5th order axial geometrical aberrations in electron microscopes. In our previous paper, we showed that 3rd order spherical aberration can be corrected by 3-SYLC doublet. After that, mainly the 5th order aberrations remain to limit the resolution. In this paper, we extend the doublet to quadruplet models also including octupole and dodecapole fields for correcting these higher order aberrations, without introducing any new unwanted ones. We prove the validity of our models by analytical calculations. Also by computer simulations, we show that for beam energy of 5keV and initial angle 10mrad at the corrector object plane, beam size of less than 0.5nm is achieved at the corrector image plane.