ANNEALING-INDUCED BLUE-SHIFT IN LUMINESCENCE BAND FROM SI-IMPLANTED SIO2 LAYER

The SiO2 layers thermally grown on Si wafers were implanted by 130 keV Si ions at liquid nitrogen temperature to a dose of 1x10(17) ions/cm( 2). From the as-implanted samples, a visible photoluminescence band ce ntered around 2.0 eV was observed. After postannealing at 1100 degrees C for 90 min another visible band in the range of 1.7 eV was detected . Interestingly, with increasing thermal annealing time, a blue shift in peak energy and an intensity variation of the 1.7 eV band were obse rved. A possible interpretation for the observations was discussed in terms of a so-called three-region model. (C) 1997 American Institute o f Phyics.