Print Email Facebook Twitter In multi electron beam systems, “Neighbours Matter” Title In multi electron beam systems, “Neighbours Matter” Author Mohammadi Gheidari, A. (TU Delft ImPhys/Hoogenboom group; Thermo Fisher Scientific) Kieft, E. R. (Thermo Fisher Scientific) Guo, X. (TU Delft ImPhys/Hoogenboom group) Wisse, M. (TU Delft ImPhys/Microscopy Instrumentation & Techniques) Kruit, P. (TU Delft ImPhys/Hoogenboom group) Date 2023 Abstract In the Multi beam source (MBS) of our Multi Beam Scanning Electron Microscope (MBSEM), an aperture lens array (ALA) splits the emission cone of the Schottky field emitter into multiple beamlets. When the apertures in the ALA are close to each other, the ALA can introduce aberrations to these beamlets through the electrostatic interaction of neighbouring apertures with each aperture's lens field. When the apertures are arranged in a square grid pattern, the aberration causes fourfold astigmatism. The effect on the beam spot is analyzed through a combination of 3D simulations and experimental validation. To counterbalance the fourfold astigmatism, a correction scheme is proposed in which a slightly non-round profile is applied to the aperture lenses. Subject ALAInteractionsMBSMBSEMNeighboring-apertures To reference this document use: http://resolver.tudelft.nl/uuid:ffec82d5-e4d4-4c72-895f-e375e1a8aea8 DOI https://doi.org/10.1016/j.ultramic.2023.113735 ISSN 0304-3991 Source Ultramicroscopy, 249 Part of collection Institutional Repository Document type journal article Rights © 2023 A. Mohammadi Gheidari, E. R. Kieft, X. Guo, M. Wisse, P. Kruit Files PDF 1_s2.0_S0304399123000529_main.pdf 17.66 MB Close viewer /islandora/object/uuid:ffec82d5-e4d4-4c72-895f-e375e1a8aea8/datastream/OBJ/view