Effect of oblique-angle deposition on early stage of Fe-Si growth

We have investigated the initial stage of Fe growth on an Si substrate during reactive oblique-angle deposition (ROAD) at 470 °C by means of atomic force microscopy, reflection high-energy electron diffraction, and high-resolution Rutherford backscattering spectroscopy. During deposition along the normal direction, many Si atoms are displaced from their lattice positions because of reactions with the deposited Fe. However, for ROAD, the number of displaced Si atoms decreases significantly along with a selective growth of nanoislands with diameters of a few 10 nm. Evidently, the local nucleation processes required for iron silicide formation are modified by the geometrical deposition conditions.