Ordered arrays of Ag nanoparticles grown by constrained self-organization

In a postdeposition annealing process, the Ag deposited at low temperature on a Si(100) substrate aggregates to regions that have been exposed to adequate dose of energetic ions. By patterning an array of such aggregation centers on the substrate, using a 50keV focused Ga+ ion beam, the migration of Ag on the patterned area during the subsequent annealing is constrained and ordered arrays of Ag nanoparticles with uniform size distribution are formed spontaneously. The mechanism and the optimum conditions for constraining the self-organization of Ag on Si by focused-ion-beam patterning are discussed.