Single2×1domain orientation on Si(001) surfaces using aperiodic Bi line arrays

Abstract

Studies of Bi heteroepitaxy on Si(001) have shown that lines grow to lengths of up to $500\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ if the substrate is heated to above the Bi desorption temperature $(500\phantom{\rule{0.2em}{0ex}}\ifmmode^\circ\else\textdegree\fi{}\mathrm{C})$ during or after Bi deposition. Unlike many other nanoline systems, the lines formed by this nonequilibrium growth process have no detectable width dispersion. Although much attention has been given to the atomic geometery of the line, in this paper, we focus on how the lines can be used to create a majority $2\ifmmode\times\else\texttimes\fi{}1$ domain orientation. It is demonstrated that the Bi lines can be used to produce a single-domain orientation on Si(001) if the lines are grown on Si(001) surfaces with a regular distribution of single height steps. This is a compelling example of how a nanoscale motif can be used to modify mesoscopic surface structure on Si(001).