Open AccessAberration model of a multibeam scanning microscope for electron beam‐induced deposition
Author(s) -
van Bruggen M. J.,
van Someren B.,
Kruit P.
Publication year - 2006
Publication title -
scanning
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.359
H-Index - 47
eISSN - 1932-8745
pISSN - 0161-0457
DOI - 10.1002/sca.4950280107
Subject(s) - optics , lens (geology) , projection (relational algebra) , scanning electron microscope , wafer , materials science , fabrication , beam (structure) , physics , optoelectronics , computer science , medicine , alternative medicine , algorithm , pathology
Abstract A multibeam electron beam‐induced deposition (EBID) system is presented, which aims at the fabrication of sub‐10 nm structures with EBID. This system consists of a multibeam source (MBS) module, delivering 100 virtual sources and a standard scanning electron microscope (SEM) column to image the 100 sources onto a wafer. In the proposed concept, beamlets are traveling off‐axis through the projection lenses, introducing off‐axis aberrations. An analytical description of the projection lens aberrations is derived and the system is optimized by tuning a field lens, which only affects the direction of the beamlets as they enter the projection system. It is found that this lens must be excited such that all beamlets go through the center of the last projection lens. This is an important design rule for the total system.