Kinetics and reconstruction of steps at the Si(001) surface

Abstract
The stability ranges of monatomic and diatomic steps on the Si(001) surface are determined by high-resolution spot-profile analysis of low-energy diffracted electrons. Diatomic steps are predominantly observed at temperatures below 1200 K. With increasing annealing temperature the steps coagulate and we identify (113) facets stabilized by a (3×1) reconstruction. These facets are stable above 1200 K, and up to 1450 K. Annealing to higher temperatures results in the formation of monatomic steps with a terrace width above the experimental coherence length.