Study of the optical properties of fused quartz after a sequential implantation with Si and Au ions

Implantation of Au ions into Si-implanted fused quartz strongly enhances the photoluminescence (PL) intensity around 630 nm measured after subsequent sample annealing at 900 degrees C. This effect is attributed to the enhancement of the formation of Si nanocrystals by the presence of Au ions and not by ion-implantation-induced defects. This conclusion was deduced by monitoring the defect formation in fused silica by 2 MeV Si ion implantation with doses ranging from 2 x 10(16) to 1 x 10(17) Si/cm(2). Some of the 4 x 10(16) Si/cm(2)-implanted samples were reimplanted at a similar depth with 10 MeV Au ions at. doses of 4 x 10(16) and 1.2 x 10(17) Au/cm(2). The absorption spectroscopy, electron paramagnetic resonance and PL measurements show the presence of B-2 and E' matrix point defects in as-prepared Si-implanted samples. As these defects disappear after annealing at 600 degrees C, the presence of a strong PL peak in samples implanted and annealed at 900 degrees C strongly suggests that the observed luminescence is produced by Si nanoparticle formation. (C) 1998 American Institute of Physics.