氨气浓度对碳纳米管生长影响的研究

Study on Influences of Ammonia Concentration on Growth of Carbon Nanotubes

利用等离子体增强化学气相沉积系统,用CH4、NH3和H2为反应气体,在沉积有100nm厚Ta过渡层和60nm厚NiFe催化剂层的Si衬底上制备了碳纳米管,并用扫描电子显微镜研究了它们的生长和结构。结果表明当氨气浓度为20%、40%和60%时,碳纳米管的平均长度分别为3.88μm、4.52μm和6.79μm,而其平均直径变化不大,均在240nm左右。最后,分析讨论了氨气浓度对碳纳米管生长和结构的影响。

Carbon nanotubes were synthesized on Si substrates deposited with 100nm Ta buffer and 60nm NiFe films in plasma-enhanced chemical vapor deposition system using CH_4, NH_3 and H_2, and their growth and structure were investigated by scanning electron microscopy. The results indicate that the average length of the carbon nanotubes is 3.88μm, 4.52μm and 6.79μm when the concentration of NH_3 is 20%, 40% and 60%, respectively, and their average diameter is seldom changed with the concentration of NH_3, they are all about 240nm. Finally, the influences of ammonia concentration on the growth of carbon nanotubes were analyzed and discussed.