Controlling the photoluminescence of ZnO:Si nano-composite films by heat-treatment (original) (raw)
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Author's personal copy White-light emission from annealed ZnO:Si nanocomposite thin films
Journal of Luminescence
a b s t r a c t As grown ZnO:Si nanocomposites of different compositional ratios were fabricated by thermal evaporation techniques. These films were subjected to post-deposition annealing under high vacuum at a temperature of 250 1C for 90 min. The photoluminescence (PL) spectra of annealed samples have shown marked improvements both in terms of intensity and broadening. Structural and Raman analyses show formation of a Zn–Si–O shell around ZnO nanoclusters wherein on heating Zn 2 SiO 4 compound forms resulting in huge UV, orange and red peaks at 310, 570 and 640 nm in PL. The new emissions due to Zn 2 SiO 4 completes white light spectrum. The study not only suggests that 1:2 ratio is the best suited for material manipulation but also shows process at the interface of ZnO nanoclusters and silicon matrix leads to new PL emissions. & 2012 Elsevier B.V. All rights reserved.
White-light emission from annealed ZnO:Si nanocomposite thin films
Journal of Luminescence, 2012
As grown ZnO:Si nanocomposites of different compositional ratios were fabricated by thermal evaporation techniques. These films were subjected to post deposition annealing under high vacuum at a temperature of 250C o for 90min. The photoluminescence (PL) spectra of annealed samples have shown marked improvements both in terms of intensity and broadening. For the first time in ZnO:Si nanocomposite films we see huge UV, red and orange peaks at 310, 570 and 640nm. Structural and Raman analysis show formation of a Zn-Si-O shell around ZnO nano clusters wherein on heating Zn2SiO4 compound forms. The new emissions are due to Zn2SiO4 which completes white light spectrum.
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