Scanning Tunneling Microscopy Observation of the Formation of the Smallest Dimer–Adatom–Stacking-fault Domain on a Quenched Si(111) Surface

Abstract

We have observed the formation of the Dimer–Adatom–Stacking-fault (DAS) domain in unreconstructed regions on quenched Si(111) surfaces by scanning tunneling microscopy at 370–380°C. It is observed that a single faulted (F)-half of the unit cell of the DAS structure is created from a corner hole of existing odd-sized F-halves at the edge of the DAS domain. It is demonstrated that the formation of the F-half in the domain growth follows the sequential size-change (SSC) model, which was proposed earlier as the formation mechanism of single isolated F-halves. The smallest DAS domain consists of three F-halves of the same size, arranged as a triangle. We have summarized the characteristic steps of the formation towards the smallest domain under the SSC model.