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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: Pseudobinary SmCo7− x Cu x intermetallic compound films with a TbCu7-type structure were prepared by sputtered (SmCo7/Cu) n multilayer. After annealing, the spacer layer Cu (0.5–1.5 nm) diffused into the SmCo7 matrix and stabilized the SmCo7 meta-stable phase. The resulting microstructure was investigated by transmission electron microscopy. Perpendicular anisotropy was obtained by introducing a Cu/Ti dual underlayer during sputtering, resulting in prefer-orientated SmCo7 (00L) X-ray diffraction peaks. This study observes a maze-like domain pattern in perpendicular anisotropy films and finds single- and multi-domain particles in correlated AFM and MFM images. [Copyright &y& Elsevier]

Abstract: This study discusses the effects of a CrPt3 alloy underlayer on the magnetic properties and microstructure of FePt films. The L12 CrPt3 phase was chemical long-range ordered at a temperature above 600°C, and the 120-nm thick CrPt3 film annealed at 800°C, resulting in ferrimagnetic behavior. The long-range ordered CrPt3 underlayer slightly increased the ordering of the L10 FePt film, as evidenced by the individual L12 CrPt3 and L10 FePt (001) superlattice peaks. An X-ray slow scan of the [FePt/CrPt3(T °C)]400°C bilayer shows that the integrated intensity of the L10 FePt (001) peaks was higher on the long-range order L12-type CrPt3 (T =600, 800) underlayer and lower on the partial short-range order L12 and A1-types CrPt3 (T =400) underlayer. However, optimal magnetic properties were obtained in the [FePt/CrPt3(400°C)]400°C bilayer. When a FePt film is deposited on a ferrimagnetic CrPt3(800°C) underlayer, the resulting bilayer shows isotropic magnetic hysteresis loops and cannot be saturated at 1.8T. Atomic force microscopy (AFM) and transition electron microscopy (TEM) show that the L12 CrPt3(800°C) underlayer exhibits coarse surface roughness and plate-like grains, respectively. From TEM images, all the FePt grains were isolated uniformly by CrPt3 matrix. [Copyright &y& Elsevier]