Quantum-sized Au structures on Si(111) studied by spectroscopic ellipsometry

Abstract

Spectroscopic ellipsometry has been used to follow the initial stages of the growth of Au on both singular and vicinal Si(111) surfaces. The imaginary part of the pseudo dielectric function shows an distinctive sharp peak at 2.7 eV, at the point where the single-domain pseudo-5 × 1 low energy electron diffraction pattern is strongest for Au growth on the stepped Si(111) surface. The singular system behaves differently. The unusual optical behaviour of the Au-induced 5 × 2 reconstruction is attributed to the recently-discovered quasi one-dimensional electronic structure of this system.