Investigation of the Photoelectric Characteristics of ZnO Nanowires on AZO Thin Film

摘要

This experiment applied the vapor transport method and the AZO catalyst, and successfully grew ZnO nanowires on silicon substrate. The results showed that the factors such as the position of growth substrate, temperature, temperature rising rate, growth time, gas flow volume, and the proportion of ZnO and carbon composition powder, could decide the quality and characteristics of ZnO nanowire. Optimal conditions for ZnO nanowire growth were: carbon and ZnO powders mixed at a 1:1 weight ratio to serve as the material for growing nanowires, located at a distance of 10 cm from the silicon substrate which already had AZO thin film deposed on it; the growth temperature was set at 1100°C for a continuous duration of 70 minutes; the flow volumes of the nitrogen and oxygen gases within the furnace pipe were 70 and 60 sccm, and the furnace pipe temperature rising rate was 20°C/min. In addition, it was observed by FE-SEM that when the substrate was away from the source material by 10 cm, there was nanowire with the radius of 0.11 μm and length of 9.3μm. By X-ray we found the characteristic wave summit of ZnO with lattice parameter a = 0.3249 nm and c = 0.5206 nm, was in fine single crystal structure and the directions were all in (002). In field emission measurements, when the current densities was 0.1 μA/cm2, the lower initial electric fields corresponding to it was 0.11 V/μm and had the best field enhancement factor with a value of 1782.