AlN Nanowires Are Synthesized By Al-Sn Flux Method

Aluminum nitride(AlN)nanowires have excellent properties such as high thermal conductivity,low thermal expansion coefficient,strong breakdown field,low dielectric constant,high electron saturation rate.AlN nanowires also have high specific area and quantum size effect of nanostructures,which are widely used in electronic and optoelectronic devices.In recent years,the synthesis and properties of AlN nanowires have attracted great interest of people.Current synthesis methods of AlN nanowires cannot simultaneously take into account the advantages of high quality,high purity and low cost.Therefore,it is necessary to develop a low-cost,easy to control and repeatable growth technology of AlN nanowires.In this paper,Al-Sn flux method was used to synthesize AlN nanowires.The effects of technological parameters on the crystallization quality and morphology of the synthesized AlN nanowires were studied by control variable method.The technological parameters we studied include raw material ratio,nitrogen pressure and growth temperature.And the growth mechanism of AlN nanowires was briefly analyzed.On the basis of the above process,the growth system was optimized,sapphire was used as the substrate,and about 47.3 ?m thick AlN film was grown by Al-Sn flux method.X-ray diffraction and Raman spectroscopy analysis showed that the AlN nanowires had a single crystal structure and good crystal quality.By scanning electron microscopy and transmission electron microscopy analysis,the diameter of the AlN nanowires is about200-500 nm and the length is up to 200 ?m,and the growth direction is perpendicular to the c axis.Finally,the luminescence properties of AlN nanowires were studied by ultraviolet-visible absorption spectrum and photoluminescence spectrum,and the defect luminescence was analyzed.The results show that AlN nanowires have broad development prospects in the field of deep ultraviolet devices and optoelectronic devices.