%0 Journal Article %T Luminescence and ellipsometry investigations of annealing effects on nano-granular ZnO. %+ Laboratoire d'Ingéniérie et Science des Matériaux - EA 4695 (LISM) %+ Laboratoire de Nanotechnologie et d'Instrumentation Optique (LNIO) %A Gilliot, Mickaël %A Hadjadj, Aomar %A Martin, Jérôme %< avec comité de lecture %@ 0022-2313 %J Journal of Luminescence %I Elsevier %V 192 %P 25-32 %8 2017-12 %D 2017 %R 10.1016/j.jlumin.2017.06.017 %K ZnO %K Ellipsometry %K Photoluminescence %K Dielectric function %K Burstein-Moss %K Renormalization %K Non-parabolicity %Z Engineering Sciences [physics]/Optics / PhotonicJournal articles %X We propose an investigation of nano-granular ZnO very thin layers ( 100 nm ), which morphologies are varied by changing the annealing temperature between 300 and 650° C. A detailed investigation of the optical properties is performed by coupling emission obtained from photoluminescence and dielectric function obtained from spectroscopic ellipsometry. The dielectric function shows a strong excitonic behavior increasing with annealing temperature. The UV emission is optimal at 450° C and the defect related visible bands gradually increase with annealing temperature. A particular attention is paid on i) the blueshift between emission and absorption UV onsets which is analyzed using contribution such as phonon replicas, carriers, bandgap renormalization, band filling and non-parabolicity; ii) the correlated evolution of absorption and emission intensities which is analyzed in terms of simultaneous curing of morphological defects and activation of intrinsic defects with temperature. %G English %L hal-02381565 %U https://utt.hal.science/hal-02381565 %~ CNRS %~ URCA %~ UNIV-TROYES %~ LISM %~ UTT