Ion-optical review of the new Melbourne two-stage microprobe

Abstract

A new two-stage microprobe is currently under construction at Melbourne. A magnetic quadrupole doublet in the first stage forms an intermediate beam focus midway along the beam line. The demagnified image is then demagnified again, by another doublet lens in the second stage. The calculated first-order properties, and aberration coefficients, of the system are presented. The relative advantages and disadvantages of the system are discussed. The two-stage microprobe is part of the ion-optical development program at Melbourne. Its current and envisaged role in this program is discussed. © 1991.