title: Generation of defects in amorphous SiO(2) assisted by two-step absorption on impurity sites.
abstract: Generation of the Si dangling bond defect in amorphous SiO(2) (E' centre) induced by tunable pulsed UV laser radiation was investigated by in situ optical absorption measurements. The defect generation efficiency peaks when the photon energy equals ∼5.1 eV, it depends quadratically on laser intensity and is correlated with the native linear absorption due to Ge impurities. We propose a model in which the generation of E' is assisted by a two-step absorption process occurring on Ge impurity sites.
authors.affiliation: Dipartimento di Scienze Fisiche ed Astronomiche, Università di Palermo, Via Archirafi 36, I-90123 Palermo, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Messina
authors.forename: M
authors.initials: M
authors.lastname: Cannas
authors.forename: R
authors.initials: R
authors.lastname: Boscaino