大电流密度碳纳米管场致发射阴极阵列的研制

Fabrication of large current density carbon nanotube based field emitters

设计了一种由TiN,Al,Fe和牺牲层构成的堆栈式催化剂层结构,采用微波等离子体化学气相沉积法实现碳纳米管阵列高速笔直生长。SEM和TEM结果表明,生长出来的碳纳米管为典型的多壁碳纳米管,长度和直径均匀,排列整齐并垂直于基底,生长速率大于5μm/min,晶格缺陷少。场致发射测试结果表明:碳纳米管的发射阵列具有良好的电流发射稳定性,最大电流密度大于6 A/cm2。紫外光电子能谱法(UPS)测试出碳纳米管的功函数为4.59 eV,则相应的场致发射陈列的场增强因子大于1 400。

A synthesis of carbon nanotubes（CNT） for field emission was grown speedly and vertically by microwave plasma chemical vapor deposition with a multi-layered stack as the catalyst lay. The SEM and TEM analysis results of the CNT samples showed that as-grown CNT were typical multi-layered ones with few defects, aligned and straight, and uniform in diameter and length. The growth rate of CNT was more than 5 μm/min. The field emission results showed that the as-grown CNT emission array presented excellent and stable field emission with current density more than 6 A /cm^3. The work function of the as-grown CNT was 4.59 eV measured by UPS and the corresponding field factor was about 1 400.