碳納米管薄膜的場發射特性研究*

碳納米管薄膜是一種能應用于場發射平面顯示器等器件中的新型冷陰極材料。該文用Ni作為催化劑，采用催化熱解法在硅片上制備了多壁碳納米管薄膜場發射陰極，反應氣體為乙炔、氫氣和氮氣。用SEM和TEM分析了其結構，證明了碳納米管的直徑在50~70 nm間。進而采用二極管結構，在優于10-4Pa的真空度下，測試了它的場發射特性，理論分析表明碳納米管薄膜的場發射實際上來源于突出于薄膜表面的部分碳納米管頂端。該陰極的開啟電場為8 V/μm；在11 V/μm時測試到了最大的發射電流密度2 mA/cm2，滿足場發射平面顯示器的要求。

In this paper, Nanotubes films are grown by thermal chemical vapour deposition on silicon substrates with nickel as a catalyst particle. The SEM, TEM has been used in order to determine the structure of the films, which show that the diameters of nanotubes are 50~70 nm. characterization has been measured on the CNT-anode setup room temperature and in a vacuum chamber. The Fowler-Nordheim plot shows a good linear fit, indicating that the emission current only comes from the protruded nanotubes. Threshold field strength of this nanotubes film is about 8 V/μm for an emission current of 1 μA, and the most field emission current densities of more than 2 mA/cm2 are measured for 11 V/μm. In addition, the bright light spot can be observed, while emitted electron bombardment fluorescent screen.