Optimal conditions for submonolayer nanoisland growth in ion beam assisted deposition

We study the optimal conditions for nanoisland growth in ion beam assisted deposition (IBAD). This situation occurs when adatom islands remain small enough to prevent the onset of three-dimensional growth, while at the same time preventing ion-induced surface erosion. We develop a rate equation model, which includes continuous deposition of adatoms and creation of vacancies, recombination of vacancies at adatom island edges and recombination of adatoms at vacancy island edges. Using this model we demonsrate that at onset between the rough and smooth layer-by-layer growth regimes there is a simple exponential relation between the largest size of the vacancy islands and the external control parameters of the growth