整齐排列的氧化锌纳米针阵列的场发射性能

Field emission properties of well-ordered ZnO nanoneedle arrays

采用简单的热蒸发方法,不使用任何催化剂,在硅基底上制备出了两种垂直于基底、整齐排列的氧化锌纳米针阵列.它们具有均匀的分布以及一致的取向和高度.场发射性能研究表明它们同时具有较低的开启和阈值场强,稳定的发射电流和长时间维持发射的能力.较低的开启和阈值场强来源于它们较高的长径比和较细的尖端;稳定发射电流和长时间维持发射的能力来源于它们在基底上均匀一致的分布以及由于较粗的根部带来的与基底的良好接触.实验结果表明整齐的氧化锌针状纳米结构阵列是一种理想的平面场发射材料.

Two kinds of vertically aligned,well-ordered zinc oxide nanoneedle arrays were synthesized on silicon substrates without any catalyst by a simple thermal evaporation method.The nanoneedle arrays have uniform distribution and unique orientation and height.The field emission study shows that both of them have not only low turn-on field and threshold field,but also the ability of stable and long time emission.The low turn-on field and threshold field result from the high aspect ratio and thin apex of the nanoneedles.The stable and long time emission are due to the uniform distribution and good contact between the nanoneedles and the substrate.The results show that regular nanoneedle arrays are ideal candidates for flat panel field emission applications.