Zno Polycrystalline Thin Films And Nano-powder Preparation And Characterization

ZnO films areⅡ-Ⅵcompound semiconductor materials with excellent piezoelectricity,photoelectricity,gas,sensitivity properties. ZnO films have many realized and potential applications such as transparent electrodes, surface acoustic wave devices, ultraviolet photodetectors, piezoelectric devices, varistors, gas sensors, photoelectron devices, etc.ZnO films are prepared by successive ionic layer adsorption and reaction method on glass sildes in this paper.The crystallographic structure and the particles of the ZnO films were analyzed with X-ray diffraction(XRD). The surface morphology and microstructure of the ZnO films were characterized by SEM. The optical properties of the ZnO films was recorded using photolum inescence spectra(PL) and UV-visible transmission spectrum. The electrical resistivity of the ZnO films was measured using four probe instrument. We gained polycrystalline ZnO films that have (002) preferred orientation, uniformity and dense morphology. The technology condition effected microstructure ZnO are analyzed and optimaled. From PL soectra,we find that ZnO films have two peaks,one is bule band on 2.72eV,one is purple band on 3.09eV,another is ultraviolet at 3.44eV. From transmission spectrum,wo find thatλon 380nm is ultraviolet absorbed. And same time, we analyses the effects of annealed temperature of ZnO films properties, will recrystallized on 450oC,the resistance decreases with increasing annealed temperature.we are use direct precipitation method prepare ZnO nanopowders in this paper, The crystallographic structure of the ZnO nanopowders was analyzed with X-ray diffraction(XRD). The surface morphology and particle size of the ZnO nanopowderss were characterized by SEM. We gained ZnO nanopowders that is a single-crystal hexagonal wurtzite structure, particle diameter about 80nm and disperse well. Meanwhile we analyses the different staples prepared ZnO nanopowders properties,wo find that particle size by ZnCl₂ and NaOH prepared is smallness then by ZnCl₂ and prepared, dispersing by ZnCl₂ and Na₂CO₃ prepared is well then by ZnCl₂ and NaOH prepared. we analyses the effects of different consistency of ZnCl₂ of ZnO nanopowders particle diameter, the optimal technology condition was that the consistency of ZnCl2 is 1.0mol/L. we analyses the effects of different decompounded temperture of ZnO nanopowders particle,the optimal decompounded temperature is 500oC.