KLA Corporation
HIGH RESOLUTION ELECTRON BEAM APPARATUS WITH DUAL-APERTURE SCHEMES

Abstract:

An electron source emits an electron beam. The electron beam is received by a beam limiting assembly. The beam limiting assembly has a first beam limiting aperture with a first diameter and a second beam limiting aperture with a second diameter larger than the first diameter. The first beam limiting aperture receives the electron beam. This beam limiting assembly reduces the influence of Coulomb interactions.