| As a direct wide band gap semiconductor, ZnO have attracted much attention forits excellent properties in the field of field emitters, UV light detectors, SAW device,light-emitting diodes, transparent electrodes and so on.Pure ZnO thin films and Co-, Al-doped ZnO thin films with a goodc-axis-orientation were prepared using electron beam evaporation. The pressure ofoxygen gas had an important effect on the appearance and properties on the ZnO thinfilm. With the increase of oxygen pressure, the films become more dense, thetransmittance went into higher and the square resistance increase with it. With theincrease of the substrate temperature, the films’ orientation to be going well, thetransmittance increased and the absorption edge became clearer. The doping of Coreduce orientation and make the crystallization worse. The increase of the Coconcentration made the transmittance reduced, the absorption edge becomeambiguous and the band gap narrowed. The crystal of Co doped ZnO thin films wouldchange to pillars. The doping of Al improved the quality and the compaction of thefilms. The transmittance was enhanced, the band gap had a larger value and the squareresistance raised first and then lowered, while the concentration of Al increased. Theanneal temperature had a great impact on the structures and optical properties. Withthe anneal temperature rising from300℃to400℃, the grains turned to the sheetstrcture and spherical structures and the optical transmittance significantly increased.ZnO and Zn0.9Ni0.1O nanorods were synthesized by a sol-gel method, and thestructure, morphology and properties of the samples were investigated. The calcinedtemperature has great influence on morphology. Nanorods-structure were obtained,while the calcined temperature was400℃. And the sample turned to the particlesfrom rods with the temperature raised. ZnO nanorods had strong emission in theultraviolet light. Zn0.9Ni0.1O nanorod shows ferromagnetism under the roomtemperature. |
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