Thermal evolution and optical properties of Cu nanoparticles in SiO2 by ion implantation

Abstract

SiO2 samples were implanted by 45keV Cu ions at a dose of 1×1017/cm2, and subjected to furnace annealing at temperatures ranging from 200 to 600°C in nitrogen atmosphere. The results indicate that the Cu nanoparticles have been synthesized by Cu ion implantation, and subsequent annealing induces the diffusion and nucleation of nanoparticles partially. The results from XPS measurements show that the Cu0 is the dominate charge state in the implanted and subsequent annealed samples. With increasing annealing temperature, the size and distribution of Cu nanoparticles have been modified gradually. The surface plasmon resonance (SPR) of Cu nanoparticles at 570nm has been observed by optical transmission spectroscopy. The strongest SPR signal at 400–600°C indicates that lots of Cu nanoparticles have grown and show good optical properties. Moreover, the luminescence has been investigated in Cu implanted and subsequent annealed samples. Possible luminescence mechanisms, such as radiation induced defects, Cu (ions or atoms) related luminescence centers, etc., have been discussed.