Influence of annealing atmosphere on metal and metal alloy nanoclusters produced by ion implantation in silica

The evolution of binary alloy clusters in sequentially ion-implanted Au/Cu or Ag/Au silica glasses has been studied as a function of the annealing atmosphere. Alloy formation has been unambiguously evidenced in the as-implanted samples. In the case of Au/Cu system, the selective effect of reducing (hydrogen containing) or oxidizing lair) atmosphere during subsequent annealing can be used to either modify the structure of the alloy or to separate the two species, respectively. On the contrary, no remarkable difference between reducing or oxidizing post-implantation annealing can be evidenced in the Au/Ag system.