Excimer laser induced spatially resolved formation and implantation of plasmonic particles in glass

Abstract

Metallic nanoparticles are important building blocks for plasmonic applications. The spatially defined arrangement of these nanoparticles in a stable glass matrix is obtained here by nanosecond excimer laser irradiation at 193 nm. Two approaches are addressed: (1) Laser induced formation of particles from a dopant material pre-incorporated in the glass, (2) Particle formation and implantation by irradiation of material pre-coated on top of the glass. Silver nanoparticles are formed inside Ag+ doped glass (method 1). Gold nanoparticles are implanted by irradiation of gold coated glass (method 2). In the latter case, with a few laser pulses the original gold film disintegrates into particles which are then embedded in the softened glass matrix. A micron sized spatial resolution (periodic arrangements with 2 µm period) is obtained in both cases by irradiating the samples with an interference beam pattern generated by a phase mask. The plasmonic absorption of the nanoparticles leads to a contrast of the optical density between irradiated and non-irradiated lines of up to 0.6.