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Gd 1.82 Eu 0.10 Li 0.08 O 3 luminescent films have been grown on Al 2 O 3 ( 0 0 0 1 ) , Si(1 0 0) and quartz substrates using pulsed laser deposition technique. On varying the substrate, the film show different surface morphologies and luminescent characteristics. While considering the distributions of size of nanoparticles grown on different substrates, out of the two types of nucleation mechanisms viz., homogeneous (in gas phase) and heterogeneous (on the substrate), the AFM observations made in this work emphasizes the major role of heterogeneous mechanism in determining the morphology of laser ablated luminescent thin films. It is suggested that Al 2 O 3 ( 0 0 0 1 ) substrate supports cubic phase of Gd 1.82 Eu 0.10 Li 0.08 O 3 films and enabling it to be better crystalline with more rougher surface than Si(1 0 0) and quartz substrates. The intensities of the f–f transitions were parameterized within the frame work of the Judd–Ofelt theory.

Nanocrystalline indium oxide films have been deposited using pulsed laser ablation technique. The effect of post-deposition annealing on the structural, morphological, electrical and optical properties of the as-deposited indium oxide thin films prepared by non-reactive pulsed laser ablation has been studied systematically using X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), UV–vis spectra, photoluminescence spectra and DC electrical measurements. X-ray diffraction analysis reveals that at higher annealing temperatures, all the films exhibit a polycrystalline structure with a preferred orientation along (4 0 0) lattice plane instead of mostly occurring (2 2 2) reflection plane. The lattice constants, biaxial strain and lattice strain of the films are calculated and correlated with annealing temperature. Particle size calculated using Debye Scherrer's formula reveals the presence of quantum dots in the films annealed at 473 K and 773 K and confirmed via SEM and AFM analysis. Mass transport mechanisms have been proposed using SEM and AFM to account for the grain coalescence process viz., Ostwald ripening mechanism, sintering, and cluster migration. A blue shift in the band gap energy values are obtained for the films and is due to quantum confinement effect as a result of their nanostructured nature. Enhanced quantum confinement effect due to the increase in porosity in the films is also observed. Efficient photoluminescence emission is observed in all the films in the UV region and corresponds well with the band gap values obtained for the films. Electrical measurements show that the electrical conductivity in the films increases with decrease in dot size.

Nanostructured Gd2O3:Eu3+ thin films were prepared by pulsed laser ablation technique. The dependence of structural, morphological and optical properties of these films on photoluminescence was systematically studied by varying the annealing temperature, Eu 3 + incorporation concentration and laser fluence. The intensity of the XRD peak from (2 2 2) crystal plane was found to increase with annealing temperature in the range 973–1173 K. Films annealed at 1173 K show a preferential growth along (2 2 2) crystal plane of the cubic Gd 2 O 3 and enhanced photoluminescence at 612 nm. XRD and Micro-Raman spectra and lattice strain investigations suggest that Eu 3 + incorporation introduce a strong lattice distortion in Gd 2 O 3 matrix. Morphological investigations using atomic force microscopy indicate a strong influence of the annealing process on the surface roughness and particle size. This kind of transparent thin film phosphors may promise for applications in flat-panel displays and X-ray imaging systems.

Nanostructured Gd2O3:Eu3+ and Li+ doped Gd2O3:Eu3+ thin films were prepared by pulsed laser ablation technique. The effects of annealing and Li+ doping on the structural, morphological, optical and luminescent properties are discussed. X-ray diffraction and Micro-Raman investigations indicate a phase transformation from amorphous to nanocrystalline phase and an early crystallization was observed in Li+ doped Gd2O3:Eu3+ thin films on annealing. AFM images of Li+ doped Gd2O3:Eu3+ films annealed at different temperatures especially at 973 K show a spontaneous ordering of the nanocrystals distributed uniformly all over the surface, with a hillocks (or tips) like self-assembly of nanoparticles driven by thermodynamic and kinetic considerations. Enhanced photoemission from locations corresponding to the tips suggest their use in high resolution display devices. An investigation on the photoluminescence of Gd2−xEuxO3 ( x = 0.10 ) and Gd2−x−yEuxLiyO3 ( x = 0.10 , y = 0.08 ) thin films annealed at 973 K reveals that the enhancement in luminescence intensity of about 3.04 times on Li+ doping is solely due to the increase in oxygen vacancies and the flux effect of Li+ ions. The observed decrease in the values of asymmetric ratio from the luminescence spectra of Li+ doped Gd2O3:Eu3+ films at high temperature region is discussed in terms of increased Eu O bond length as a result of Li+ doping.

Nanostructured Gd2O3: Eu3+ thin films were prepared by pulsed laser ablation technique. The dependence of structural, morphological and optical properties of these films on photoluminescence was systematically studied by varying the Eu3+ incorporation concentration. Micro-Raman and XRD analysis indicate that Eu3+ incorporation strongly perturbs the cubic Gd2O3 structure and suppresses the grain growth. For 0.10 mol Eu3+ doped Gd2O3 films deposited under a vacuum of 10-6 mbar when subjected to annealing at 1173 K give transparent films exhibiting intense photoemission at 612 nm due to 5D0-7F2 transition. The Eu3+ incorporation concentration above 10 mol %, decreased the luminance intensity may be due to concentration quenching effect.