4×1 reconstruction of indium deposited on vicinal Si(111) surfaces

The Si(111)-(4×1) In reconstruction normally exists in three domains of double-row ridges along three equivalent 〈1¯10〉 directions on a flat Si(111) substrate. Using vicinal Si(111) surfaces as substrates, scanning-tunneling-microscopy images show the existence of only a single domain of the (4×1) reconstruction with the double rows aligning with the [1¯10] step edges when the surface is misoriented toward the [1¯ 1¯2] direction. When the vicinal sample is misoriented toward the opposite, i.e., [112¯], direction, however, all three domains are present. We performed impact-collision ion-scattering spectrometry experiments on the single-domain surface and the results confirm a model in which In adatoms occupy ${\mathit{H}}_3$ and ${\mathit{T}}_4$ sites with 1/2-monolayer coverage.