Influence of the implantation and annealing parameters on the photoluminescence produced by Si hot implantation

We report an investigation on the effect of the fluence and annealing time on the photoluminescence (PL) from Si nanocrystals produced by hot implantation of Si into a SiO2 matrix followed by thermal treatment in nitrogen. We have varied the implantation fluence in a wide range, from 0.35 × 1017 to 4 × 1017 Si/cm2. In addition, the PL evolution with the annealing time (1 up to 15 h) was studied for the samples implanted with fluences between 1 × 1017 and 4 × 1017 Si/cm2. After annealing the spectra present two PL bands: one centered at 780 nm and a second one around 1000 nm. The influence of the studied parameters on the PL behavior of both bands suggests different origins for their emission. The results are discussed in terms of current models.