Reaction of Sb on In/Si(111) surfaces: Heteroepitaxial InSb(111) formation

Sb deposition and reaction on In/Si(111) were investigated by low-energy electron microscopy, low-energy electron diffraction, synchrotron radiation micro X-ray photoelectron spectroscopy and synchrotron radiation X-ray photo-emission electron microscopy. The Sb deposition process strongly depends on the initial In/Si(111) phases such as √3×√3, √31×√31 and 4×1. On the In/Si(111) surface where two phases co-exist, the diffusion of In atoms, which are released by the attack of Sb, modifies the deposition and reaction process of Sb. On a mixed In/Si(111) √31×√31+4×1 surface, an InSb(111) 2×2 structure with elongated domains initially forms along steps. Then In atoms are replaced by Sb atoms and InSb(111) 2×2 transforms into Sb/Si(111) 2×1 by further reaction with Sb atoms. Here, the existence of the 4×1 phase promotes the formation of larger InSb(111) 2×2 domains.