The main luminescence bands in silica SiO2are the red luminescence R (650 nm, 1.9 eV) of thenon-bridging oxygen hole center, and the blue band B (460 nm, 2.7 eV) and ultraviolet luminescence UV (290 nm,4.3 eV), both commonly related to oxygen-deficient centers. In the present work, we will enhance or replaceeither the first or second constituent of SiO2, i.e., silicon or oxygen, isoelectronically by additional implantationof the respective ions. Thus, thermally oxidized SiO2layers have been implanted by different ions of theIV group (C, Si, Ge, Sn, Pb) and of the VI group (O, S, Se) with doses up to 5×1016cm–2, leading to an atomicdopant fraction of about 4 at % at the half depth of the SiO2layers. Very surprisingly, the cathodoluminescencespectra of oxygen- and sulfur-implanted SiO2layers show, besides the characteristic bands, a sharp and intensivemultimodal structure beginning at the green region at 500 nm up to the near infrared. The energy step differencesof the sublevels equal on average 120 meV, and indicate vibration associated electronic states, probablyof interstitial molecules.
Pleiades publishing , 2007. Vol. 41, 453-457 p.