Effect of co-doping on photosensitivity of teos sol-gel glasses

The creation of photosensitive centers in germano-silica sol-gel glasses related to oxygen deficient centers has been analyzed. The principal objectives are fabrication and studies of properties of germanium oxygen deficient centers (GODCs) and new centers in glass system. Dopants as aluminum and lithium ions were introduced in the glass. Formation and transformation of oxygen deficient centers are studied through the variation of optical absorption spectra of these specimens. Effect of UV irradiation on the samples was analyzed. Presence of small concentrations of lithium ions in germano-silica glasses promotes the formation of GODCs and enhances the photosensitive response of them improving the photochemical conversion of GODC to other centers. A new center [GeO4-/Li+] is formed. Summarizing, the doping of glass with aluminum and lithium ions enhances its photosensitivity, thus opening a new avenue in application of developed technique in fabrication of photosensitive devices for telecommunication industry.