针对碳纳米管场致发射冷阴极在微波、毫米波电真空辐射源器件中的应用需求, 采用2 μs, 20 kV的脉冲高压对碳纳米管场致发射冷阴极的脉冲发射特性进行了实验研究. 通过改变阴阳极间距, 对碳纳米管冷阴极发射电流特性及发生脉冲高压打火后的碳纳米管冷阴极发射特性进行了测试研究. 在直径为4 mm的圆形平面碳纳米管冷阴极上获得最大发射电流16 mA, 电流密度为127 mA/cm2. 以实验测试数据为基础, 结合粒子模拟软件建立碳纳米管冷阴极场致发射仿真模型, 给出了该仿真模型的相关参数, 为下一步设计研制碳纳米管冷阴极电子光学系统及相关辐射源器件奠定基础.
For the application requirement of a carbon nanotube clod cathode (CNCC) used in the microwave and millimeter wave electric vacuum radiation source devices, pulsed field emission characteristics of CNCC are experimentally investigated by a 2 μs/20 kV high-voltage modulator in this paper. The pulsed field emission currents for different distances between anode and cathode and those of CNCC after the pulsed high-tension arc has occurred many times are studied. A maximal emission current of 16 mA is tested for CNCC with a 4 mm diameter emission disk, and the emission current density is achieved to be 127 mA/cm2. Based on the experimental results, the field emission simulation model of CNCC is established by PIC simulation software. Simulation results show that this simulation model is suited for describing the experimental results and laying the foundation for the development of CNCC electron optical system and radiation source devices.