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Abstract: (00l) CeO2 films deposited on r-cut sapphire were irradiated by N+ ions at fluences of 1×1016, 5×1016 and 1×1017 ion/cm2 at room temperature and then annealed at 200–900°C in O2 ambient. X-ray diffraction results showed that there was no change for the orientation and crystallinity of CeO2 film after irradiation. However, the diffraction peaks became sharper after annealing at 900°C. Atomic force microscope measurements revealed isolated voids after ion irradiation. The optical transmittance spectra indicated a blueshift of band gap due to the valence transition of Ce3+→Ce4+ induced by thermal annealing. As-deposited films exhibited three photoluminescence bands at 300–390, 380–550, and 460–550nm. A new emission band peaked at 670nm appeared while the emission band at 460–550nm disappeared after annealing. The CeO2 films show good thermal stability and irradiation resistance except some isolated voids in this work. [Copyright &y& Elsevier]

Abstract: ZnO:Al thin films doped with different aluminum concentrations were deposited on (0001) sapphire substrates by the sol–gel technique. Thermal annealing of ZnO:Al films was carried out in an argon ambient at various annealing temperatures from 600 to 950°C. The effects of thermal annealing and dopant concentration on the optical properties of ZnO:Al thin films were investigated. It is found that near band edge UV emission is enhanced by increasing the annealing temperature and dopant concentration. But defect-related deep-level emission decreases with the increasing dopant concentration and thermal annealing has little influence as the deep-level emission. The optical band gap of ZnO:Al films increases from 3.21 to 3.25eV on increasing the dopant concentration from 0.01% to 1%. The optical transmittance decreases in the visible region, while it increases in the ultraviolet region with an increase in the annealing temperature. [Copyright &y& Elsevier]