EFFECTS OF GAMMA-RAY IRRADIATION ON PHOTOLUMINESCENCE SPECTRA FROM SI-RICH SILICON-OXIDE

Si-rich silicon oxide films with thicknesses of about 1.2 mu m were de posited on p-type Si substrates by the RF magnetron sputtering techniq ue. After annealing at different temperatures in a N-2, atmosphere, th e photoluminescence spectra of all samples show two main peaks located at about 710 and 800 nm. After gamma-ray irradiation, these two PL pe aks increase 3-5 times in intensity. Moreover, a strong new 580 nm pea k emerges from the Pt spectra in all samples. The positions of all thr ee Pt peaks do not show any evident shift when the measurement tempera ture increases from 10 to 300 K. These experimental results can best b e explained by the model that photoemission occurs through the lumines cence centers, rather than the nanometer silicon particles, in the Si- rich silicon oxide films. Copyright (C) 1997 Elsevier Science Ltd.