接触电阻对碳纳米管场发射的影响

摘要

After accounting for a contact resistance between carbon nanotube（CNT） and substrate,the local electric filed of top of CNT were calculated by combining an improved floated sphere model and the Fowler-Nordheim theory for understand the effect of the contact resistance on field emission from CNT.It is found that the field emission current is limited and current saturation and nonlinear characteristics of the Fowler-Nordheim plots are produced by the contact resistance in region of high electric field.The origin can be attributed to the local electric filed of top of CNT remarkably debases as compared to without the contact resistance.%基于改进的悬浮球模型。计算了碳纳米管和衬底间的接触电阻存在时碳纳米管顶端的局域电场,并结合FowlerNordhenim（F-N）场发射规律研究了接触电阻对碳纳米管场发射的影响.研究表明,接触电阻的存在,在高电场区域接触电阻抑制了碳纳米管的电子场发射,导致在高电场区域出现电流饱和及FN直线偏折现象.其原因可归结为接触电阻使得在碳纳米管顶端的局域电场相对于没有接触电阻时相对地减少.