Encapsulation of atomic-scale Bi wires in epitaxial silicon without loss of structure

Abstract

We demonstrate, using x-ray diffraction, that we have taken one-dimensional Bi nanolines fabricated on a Si(001) surface, and buried them in crystalline silicon while retaining both their one-dimensional characters and important aspects of their structure. In particular, after burial, the nanolines retain the two-by periodicity associated with their surface structure along their length. We have used density functional theory calculations to model a structure for these buried nanolines, whose minimum length can be estimated to be 100 nm from the coherence length of the x-ray measurements.