State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou, 510275 China.
Nanoscale. 2019 Feb 14;11(7):3370-3377. doi: 10.1039/c8nr08984a.
In pursuing high emission current density and high brightness, it is difficult to avoid vacuum breakdown in nanowire cold cathode systems, which will shorten the lifetime of the electron sources. Therefore, investigations on the vacuum breakdown process are important for semiconductor nanowire point electron sources. In this study, non-catastrophic breakdown phenomena that could extend the lifetime of the nanowire electron source were observed in the field emission processes of individual defective WO3-x nanowires. In this non-catastrophic breakdown process, only part of the nanowire emitter was destroyed. After the breakdown, the remaining part of the nanowire could still emit electrons, and due to the shortening of its length, the maximum field emission current density of the remaining nanowire was increased. These results are consistent with the prediction given by theoretical calculations. A defect-related electrical transport induced breakdown mechanism and Nottingham effect induced cooling effect were proposed to be the main causes of this phenomenon. Our work provides an approach for designing long lifetime semiconductor nanowire point electron sources.
在追求高发射电流密度和高亮度的过程中，纳米线冷阴极系统很难避免真空击穿，这将缩短电子源的寿命。因此，研究半导体纳米线点电子源的真空击穿过程非常重要。在这项研究中，在单个缺陷 WO3-x 纳米线的场发射过程中观察到了可以延长纳米线电子源寿命的非灾难性击穿现象。在这个非灾难性击穿过程中，只有纳米线发射器的一部分被破坏。击穿后，纳米线的剩余部分仍能发射电子，并且由于其长度缩短，剩余纳米线的最大场发射电流密度增加。这些结果与理论计算的预测一致。提出了一种与缺陷相关的电输运诱导击穿机制和诺丁汉效应诱导冷却效应，作为这种现象的主要原因。我们的工作为设计长寿命半导体纳米线点电子源提供了一种方法。
