MICROSTRUCTURE AND OPTICAL PROPERTIES OF ERBIUM DOPED SILICA-BASED FILMS VIA FLAME HYDROLYSIS DEPOSITION AND AEROSOL DOPING

Silica-based films on Si fabricated by flame hydrolysis deposition were doped with erbium ions using an aerosol doping technique, and co-doped with GeO2, P2O5 and B2O3. The erbium solution concentration was varied from 4 to 8wt%. The results show that the refractive index of the films is not changed with erbium addition and no OH group is detected for erbium doped silica-based films. An obvious peak was observed at 1.542 mu m with the FWHM of 65 nm, which corresponds to the I-4(13/2) -> I-4(15/2) transition. With the increase of Er solution concentration, the photoluminescence (PL) intensity first increases, then decreases above 6wt% Er solution concentration. The decrease in PL intensity with concentration is attributed to concentration quenching caused by Er-Er interaction. The dependence of PL intensity on pump power intensity further confirms the concentration quenching is cooperative upconversion.