Blue-light emission from sputtered Si:SiO2 films without annealing

We observed a photoluminescence (PL) spectrum at room temperature that had a peak with full width of half maximum (FWHM) of 0.38 eV near the band gap energy of 3.2 eV from a Si:SiO2 sputtered film without annealing. Blue-light emission could be seen by the naked eye. A low-intensity PL peak with FWHM of 0.20 eV was also observed at around 1.6 eV. We have already demonstrated that our method automatically forms Si clusters contributing to visible emission. Our results did not contradict the well-founded conjecture that there were two mechanisms of emission from Si clusters: emission at 1.6-1.7 eV due to the surface state of the oxidized Si nanocrystals and emission at the band gap energy originating from the quantum confinement effect. (C) 2003 American Institute of Physics.