Implantation and laser annealing of Cu nanoparticles in silica

Silica samples with Cu nanoparticles synthesized by ion implantation at an energy of 50 keV, dose of 8×1016 ions/cm2 and current density of 10 μA/cm2 were annealed using several pulses from a high-power KrF excimer laser at ultraviolet wavelength. The formation and modification of metal nanoparticles after implantation and laser treatment were studied by optical reflectance and transmittance. Generally, changes induced by laser pulses suggest a reduction in the size of the metallic nanoparticles or/and their oxidation without diffusion of Cu atoms inward in the silica matrix. The particle size and oxidation of copper particles are discussed within the framework of the Mie theory.