Impact of the annealing temperature on the optical performances of Er-doped Si-rich Silica systems
Résumé
Series of Er-doped Si-rich silicon oxide (SRSO:Er) layers were grown by magnetron sputtering at different temperatures from ambient to 500°C and then annealed between 600°C and 1100°C. They were characterized by spectroscopic and time-resolved photoluminescence (PL) measurements. Significant PL was detected at 1533 nm from the as-grown samples at T300°C excited by a non-resonant wavelength (476 nm), hence indicating the formation of Si-based sensitizers during the growth process. The PL intensity and the decay lifetime of Er3+ ions were both greatly increased with the annealing temperature. An optimum temperature of annealing is obtained at 800°C, which is expected to favor the formation of very dense and small sensitizers. The fraction of Er coupled to sensitizers was found nearly 6-7 times higher than that reported so far in the literature.