Laser annealing of SiO2 glass with copper nanoparticles

Composite layers formed in SiO2 by implantation of 50‐keV Cu+ ions with a dose of 8·1016 cm−2 at an ion current density of 10 μA/cm2 have been investigated. It is shown that ion implantation carried out under the chosen conditions allows one to synthesize copper nanoparticles in the surface region of a dielectric. The exposure of composites to high‐power pulses of an excimer krypton laser at a wavelength in the SiO2 transmission region has been investigated. In the absence of effective optical absorption by a glass substrate, the dynamics of the change in the structure of the layer with metallic nanoparticles is determined by the number of laser pulses. It has been established that at the initial stage of pulsed irradiation fragmentation of the largest nanoparticles occurs followed by the inverse process of their agglomeration as a result of slight heating of the glass matrix; further exposure to the laser irradiation leads to an effective accumulation of energy in the particles and, as a consequence, to their melting and dissociation into small clusters and individual atoms.