Synthesis of Nanostructured Ag and Ag-Cu Alloy Thin Films

In the present work, thin alloy films of pure silver and silver-copper (Ag-Cu) have been deposited by DC magnetron co-sputtering at room temperature on silicon substrates. The elemental composition is determined by Rutherford backscattering spectrometry (RBS). X-ray diffraction (XRD) spectra of the deposited thin films confirm the formation of alloys. The films were further annealed in an inert (Ar) atmosphere at 200, 400 and 600 °C for one hour each. Nanoparticles are formed on the surface after annealing, as confirmed by field emission scanning electron microscopy (FESEM) images. The size of the nanoparticles increases with annealing temperature. Nanostructured alloy films of Ag-Cu have various plasmonics based applications. They are more durable due to their immunity to oxidation. Moreover, the tunability of surface plasmon resonance in alloy films adds to their versatility.