Zno Nanowire Self-assembly Controlled Growth Study

ZnO nanowires have been grown on metal coated substrates by Chemical Vapor deposition and catalytic technology and studied the factors which effect the growth of ZnO nanowires. The growth mechanism of ZnO nanowires was also discussed. This paper reports the UV sensitive characteristic and spectral responsibility of ZnO nanowires.The structure, morphology and photoelectric properties of ZnO nanowires have been studied by X-ray diffraction (XRD), scanning electron microscope (SEM) and atom force microscope (AFM). We found that ZnO powder can be optimally decomposed in 1350℃. The diameter and growth area of ZnO nanowires strongly depended the size and distribution of catalyst. We can get different dimension in the different growth temperature. Then the ZnO nanowires arrays with the optimum properties were obtained by improving the process conditions. Experiment proved the growth of ZnO nanowires is based VLS mechanism, but have some different with traditional VLS mechanism. While using Ag as the catalyst, the catalyst appers in the bottom of the nanowires, we think it is because Ag and Si have formed Ag-Si alloy. We have proposed the growth model of ZnO nanowires wile using two kinds of catalyst.The photoelectric characteristic research of ZnO nanowires shows that a-b orientation ZnO nanowires arrays has very strong UV sensitive characteristic, and it is very fast response (smaller than 50mS). Finally, we discussion the impact on response speed of light of ZnO nanowires in the different oxygen atmosphere, the result shows that the photocurrent increases with decline that oxygen presses, but electric current resumes become slow.