Growth of metallic nano-clusters and control over their size, chemical composition and density are critically important for catalysis. In this work we combine a method to deposit metallic and oxide nano-clusters using weakly bound buffer layer as an intermediate substance to control the clusters size with laser patterning that modulates their surface density. Employing multiple deposition cycles, the density of nano-clusters can be varied over several orders of magnitude, reaching densities that cannot be acheived by direct metallic deposition. Using optical probes, the size selected diffusion of gold nano-clusters on metallic and oxygen modified surfaces has been studied. Information on clusters mobility is important for understanding and control the thermal stability of clusters toward the development of sintering resistant catalysts.
The same technique was further developed at thicker film thickness to pattern the layer at the sub-micron scale employing a single laser pulse. This technique is discussed as a novel approach for lithography.
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