Synthesis and characterization in AuCu–Si nanostructures

Au/Cu bilayers with different Au:Cu concentrations (25:75, 50:50 and 75:25at.%) were deposited on Si(100) substrates by thermal evaporation. The thicknesses of all Au/Cu bilayers were 150nm. The alloys were prepared by thermal diffusion into a vacuum oven with argon atmosphere at 690K during 1h. X-ray diffraction analysis revealed different phases of AuCu and CuSi alloys in the samples after annealing process. CuSi alloys were mainly obtained for 25:75at.% samples, meanwhile the AuCuII phase dominates for samples prepared with 50:50at.%. Additionally, the Au:Cu alloys with 75:25at.%, produce Au2Cu3 and Au3Cu phases. The formed alloys were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) to study the morphology and the elemental concentration of the formed alloys. •AuCu/Si alloy thin films were prepared by thermal diffusion.•Alloys prepared with 50at.% of Au produce the AuCuII phase.•Alloys prepared with 75at.% of Au produce Au3Cu and Au2Cu3 phases.•All alloys present diffusion of Si and Cu through the CuSi alloy formation.