Imaging surfaces with reflected electrons from a field emission scanning tunnelling microscope: image contrast mechanisms

Abstract

Electrons backscattered from a scanning tunnelling microscope operating in the field emission mode have been collected to produce images of a rough Si(1 1 1) surface. We have obtained a spatial resolution of about 40 nm in such images. Comparison between backscattered electron images and topographic images reveals that edge enhancement and shadowing are important contrast mechanisms.