Photoluminescence emission under thermal annealing of Silica and Titania nanospheres arrays

Experimental results on the influence of the annealing time on the photoluminescence (PL) emission of silica array is presented. Bilayers of titania and silica with a thickness of 100 nm and 600 nm, respectively were uniformly deposited on crystalline silicon (c-Si) substrates, and exposed to annealing process from 0 to 60 minutes in intervals of 10 minutes at 1100°C in a nitrogen atmosphere. Our results showed that annealed samples during 30 minutes present PL emission 110 times larger than samples without annealing. Influence of the nanoparticles array distribution on the PL intensity before and after the annealing process is also presented.