Study ofsilicananoparticlesproduced by ultrashort laser pulses

Abstract

Fused silicasamples were exposed to tightly focused ultrashort laser pulses in air for creating laser tracks.
The produced laser tracks and nanoparticles were examined by field emission scanning electron
microscopy (FESEM) for the study of their morphological characteristicswhile energy dispersive x-ray
analysis (EDS) was used to ascertain the chemical composition of the particles. For further investigation
the particles collected from the tracks by ultra-sonication in ethanol were analyzed by transmission
electron microscopy (TEM)and selected electron diffraction (SAED). The electron diffraction revealed
amorphous structure of the ablation particles. The mechanism of particle formation with different
morphology has been proposed based on the electron microscopy observations.Fine particles were
directly ejected from the specimen surface in the plasma plume while larger particles and filaments were
resulted from agglomeration of fine particles during condensation while irregular shaped particles with
sharp edges were resulted bydirect exfoliation from the surface