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Photochemical generation of E' centre from Si-H in amorphous SiO2 under pulsed ultraviolet laser radiation

F. Messina·M. Cannas
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Abstract

In situ optical absorption spectroscopy was used to study the generation of E' centres in amorphous SiO_2 occurring by photo-induced breaking of Si-H groups under 4.7eV pulsed laser radiation. The dependence from laser intensity of the defect generation rate is consistent with a two-photon mechanism for Si-H rupture, while the growth and the saturation of the defects are conditioned by their concurrent annealing due to reaction with mobile hydrogen arising from the same precursor. A rate equation is proposed to model the kinetics of the defects and tested on experimental data.

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F. Messina, M. Cannas. 2007-03-02. Photochemical generation of E' centre from Si-H in amorphous SiO2 under pulsed ultraviolet laser radiation. https://arxiv.org/abs/cond-mat/0703061

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