Zheng He, Liu Yu, Cao Fan, Wu Shujing, Jia Shuangfeng, Cao Ajing, Zhao Dongshan, Wang Jianbo
School of Physics and Technology, Center for Electron Microscopy and MOE Key Laboratory of Artificial Micro- and Nano-structures, Wuhan University, Wuhan 430072, China.
Sci Rep. 2013;3:1920. doi: 10.1038/srep01920.
Nanopore-based sensing has emerged as a promising candidate for affordable and powerful DNA sequencing technologies. Herein, we demonstrate that nanopores can be successfully fabricated in Mg alloys via focused electron beam (e-beam) technology. Employing in situ high-resolution transmission electron microscopy techniques, we obtained unambiguous evidence that layer-by-layer growth of atomic planes at the nanopore periphery occurs when the e-beam is spread out, leading to the shrinkage and eventual disappearance of nanopores. The proposed healing process was attributed to the e-beam-induced anisotropic diffusion of Mg atoms in the vicinity of nanopore edges. A plausible diffusion mechanism that describes the observed phenomena is discussed. Our results constitute the first experimental investigation of nanopores in Mg alloys. Direct evidence of the healing process has advanced our fundamental understanding of surface science, which is of great practical importance for many technological applications, including thin film deposition and surface nanopatterning.
基于纳米孔的传感技术已成为一种有前景的候选技术，有望用于实现经济实惠且功能强大的DNA测序技术。在此，我们证明了通过聚焦电子束（电子束）技术可以在镁合金中成功制造纳米孔。利用原位高分辨率透射电子显微镜技术，我们获得了明确的证据，即当电子束扩散时，纳米孔周边会发生原子平面的逐层生长，导致纳米孔收缩并最终消失。所提出的修复过程归因于电子束诱导的镁原子在纳米孔边缘附近的各向异性扩散。讨论了一种描述所观察到现象的合理扩散机制。我们的结果构成了对镁合金中纳米孔的首次实验研究。修复过程的直接证据推进了我们对表面科学的基本理解，这对许多技术应用具有重要的实际意义，包括薄膜沉积和表面纳米图案化。
