Origins of optical absorption between 4.8 and 4.9eV in silica implanted with Si and with O ions

Diffusion and reactions of interstitial oxygen species in amorphous SiO2: A review

“…Paramagnetic species found in some non-porous a-SiO 2 samples exposed to c-rays [109,110] may be HO Å 2 rather than O ÅÀ 2 . Recently, a new EPR signal, probably attributed to oxygen related centers, has been reported in heavily O + -ion-implanted a-SiO 2 , in which a large fraction of the implanted oxygen is considered to be turned to interstitial species [111].…”

Review of some experiments in the 50 year saga of the E′ center and suggestions for future research

“…The stoichiometry, x, in a layer $600 nm thick was varied over the range 0.025 < x < 2.5 at.% by implanting Si or O over a range of energies to produce a layer with constant concentration, ±5%, of implanted ions in Type III silica samples [20]. This results in the generation, of a series of EPR-active centers in various intensities [21,22]. The concentrations of E 0 spins, peroxy radicals (POR), non-bridging oxygen hole centers (NBOHC) and a new EPR component, the OS center, were determined by double numerical integration of EPR spectra using a comparison technique involving a fixed Si:P standard sample [23].…”

The effect of implanting nitrogen on the optical absorption and electron paramagnetic resonance spectra of silica

“…This task however is generally complicated by overlap of the various observed EPR spectral components. The method of unraveling the components and the density determination of the various individual defect types (components) has been outlined in detail elsewhere [26]. The defect density inference was much aided by computer-assisted simulation of the observed powder pattern spectra, in particular for the broad powder pattern such as exhibited by POR.…”