Indium-induced triple-period atomic wires on a vicinal Si(111) surface: Ln/Si(557)

Abstract

An indium-induced one-dimensional (ID) surface reconstruction on a Si(557) surface was studied by the combined approach of scanning tunneling microscopy (STM) and first principles calculations. Low-energy electron diffraction revealed a (1 x 3) phase with a triple-period along the step edge direction, which was also confirmed by STM. The STM images showed that the ID structure consists of two atomic chains. One is located on the terrace and consists of triple-period bright protrusions. The other shows a weak x3 modulation at the step edge. Five atomic structure models based on the In adatom of a In/Si(lll)-√3 x √3 surface were considered to figure out the underlying structure of the STM images of the In/Si(557)-1 x 3 surface. Interestingly, a heterogeneous In-Si adatom chain model reproduced most of the features of STM images and was the most stable energetically at a wide range of In chemical potential. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.