Real-Time Observation of Self-Interstitial Reactions on an Atomically Smooth Silicon Surface

•The submonolayer gold deposition onto the silicon surface at high temperatures is supplemented by the self-interstitial formation in the subsurface area and the consequent out-diffusion to the surface sinks, which initiates the formation of two-dimensional islands.•The kinetic growth behavior of the nucleated two-dimensional islands is dominated by the reactions at the atomic step edges.•The activation energy for the interaction of self-interstitials with the surface and energy barrier for gold penetration into the silicon bulk through the surface are estimated.