碳纳米管场致发射结构的研究

Study of the Field Emission Structure of Carbon Nanotubes

碳纳米管以其特有的电学性质而成为一种优良的冷阴极材料。在场致发射器件中 ,真空度是决定发射稳定性的一个重要因素。如果碳纳米管阴极附近的真空度太低 ,将产生打火、气体电离、离子回轰阴极等问题 ,将导致阴极发射电流的迅速衰减。本文通过对基于碳纳米管冷阴极的二极管和三极管的场发射特性的实验 ,分析了残余气体压强与外加电压、发射体工作时间的关系以及碳纳米管阵列的I E曲线 。

With its unique electric characteristics,carbon nanotube is an excellent material for cold cathode. In the field emission devices, the vacuum determines the emission stability obviously .If the vacuum near the cathode is too poor, it will generate spark, gas ionization and ion bombardment on cathode, which can result in a fast attenuation of the emission current. In this paper, the field emission experiments of a diode and a triode based on carbon nanotube cold cathode are performed, the relationship between the gas pressure and the applied voltage, the working time of the emitter are studied. The results can be useful to optimize the designation of the triode structure of carbon nanotubes.