The XPS, depth profile analysis and photoluminescence studies of pulsed laser deposited SrAl2O4:Eu2+, Dy3+ thin films prepared using different laser fluencies [ READ ]
P.D. Nsimama, O.M. Ntwaeaborwa and H.C Swart
SrAl2O4:Eu2+, Dy3+ thin films were grown on silicon (Si) (111) substrates using the pulsed laser deposition (PLD) technique to investigate the influence of the laser fluence on the structure, morphology and photoluminescent properties of the films. The atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray Diffraction (XRD), energy dispersive x-ray spectroscopy (EDS), photoluminescence (PL) spectroscopy and the x-ray photoelectron spectroscopy (XPS) were used to characterize the films. The SrAl2O4:Eu2+, Dy3+ thin films gave two green PL emissions peaks coming from Eu2+ ions occupying the two Sr2+ sites in the SrAl2O4 host lattice. The green emissions were attributed to 4f65d1 ? 4f7 transitions of Eu2+. The films with well-defined grains gave superior PL intensity and long afterglow characteristics. The EDS and XPS results showed that the films consisted of all the major elements (i.e. Sr, Al and O) present in SrAl2O4:Eu2+, Dy3+ material. The carbon (C) and the Si peak from the substrate were also identified. The XPS depth profile results showed a linear relationship of the film thickness with the laser fluence. The variations of surface morphological and topographical properties of the films with the laser fluencies are discussed.
P.D. Nsimama, O.M. Ntwaeaborwa and H.C Swart
SrAl2O4:Eu2+, Dy3+ thin films were grown on silicon (Si) (111) substrates using the pulsed laser deposition (PLD) technique to investigate the influence of the laser fluence on the structure, morphology and photoluminescent properties of the films. The atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray Diffraction (XRD), energy dispersive x-ray spectroscopy (EDS), photoluminescence (PL) spectroscopy and the x-ray photoelectron spectroscopy (XPS) were used to characterize the films. The SrAl2O4:Eu2+, Dy3+ thin films gave two green PL emissions peaks coming from Eu2+ ions occupying the two Sr2+ sites in the SrAl2O4 host lattice. The green emissions were attributed to 4f65d1 ? 4f7 transitions of Eu2+. The films with well-defined grains gave superior PL intensity and long afterglow characteristics. The EDS and XPS results showed that the films consisted of all the major elements (i.e. Sr, Al and O) present in SrAl2O4:Eu2+, Dy3+ material. The carbon (C) and the Si peak from the substrate were also identified. The XPS depth profile results showed a linear relationship of the film thickness with the laser fluence. The variations of surface morphological and topographical properties of the films with the laser fluencies are discussed.
