碳纳米管阴极的强流脉冲发射性能研究  

Research on intense pulsed emission of carbon nanotube cathode

作　　者：廖庆亮[1] 张跃[1,2] 夏连胜[3] 黄运华[1] 齐俊杰[1] 高战军[1] 张篁[3] 

机构地区：[1]北京科技大学材料物理与化学系 [2]北京科技大学新金属材料国家重点实验室,北京100083 [3]中国工程物理研究院流体物理研究所

出　　处：《物理学报》2007年第9期5335-5340,共6页Acta Physica Sinica

基　　金：国家杰出青年基金(批准号:50325209);国家重大国际(地区)合作研究项目(批准号:50620120439;2006DFB51000)资助的课题.~~

摘　　要：采用丝网印刷和涂敷方法制备了两种碳纳米管阴极,并研究了两种阴极的强流脉冲发射特性,表征了阴极表面碳纳米管的形貌及分布.研究结果表明在脉冲宽度为100ns、电压为1.64×106V的脉冲电场下,涂敷法制备阴极的场发射电流最高达5.11kA,最高发射电流密度达260A/cm2.丝网印刷法制备阴极的场发射稳定性优于涂敷法制备阴极,但其发射电流低.阴极表面发射体的形貌与分布影响了阴极的脉冲发射性能.碳纳米管阴极的脉冲发射机理为爆炸电子发射.碳纳米管阴极可以作为强流电子束源在高能微波器件中得到应用.Two different carbon nanotube （CNT） cathodes have been made by using screen-printing and also by coating. Pulse emission properties of the two cathodes were studied, and the cathode＇s surface morphology was characterized. Research results show that the CNT cathode is capable of generating pulsed beams of a few kilo-amperes. The pulsed field emission properties of the cathode were tested in a diode structure powered by a high-voltage generator（under conditions of 2×10 ^-3 Pa, 100ns, 1.64MV）. The results reveal that the emission current of the cathode made by coating can attain 5.11 kA, and the highest emission current density is 260 A/cm^2. The stability of cathode made by screen-printing is better than that made by coating. The pulsed emission mechanism of carbon nanotubes is shown to be explosive electron emission. This carbon nanotube cathode appears to be suitable for high-power microwave device applications.

关 键 词：碳纳米管 阴极 脉冲发射 强电流 

分 类 号：O462[理学—电子物理学]