Department of Materials Engineering, Technion-Israel Institute of Technology, Haifa, Israel.
Nanotechnology. 2010 Nov 26;21(47):475301. doi: 10.1088/0957-4484/21/47/475301. Epub 2010 Oct 29.
Nanometer length-scale holes (nanopores) are often formed in amorphous materials for fundamental studies of molecular mass transport. In the current study, electron beam irradiation in the transmission electron microscope was used to form nanopores in a crystalline material (Si). Analysis of the nanopores showed that they are formed by knock-on of atoms by the high energy incident electron beam, and surface diffusion is partially responsible for the hour-glass shapes that are found for some nanopores. Energetically favorable three-dimensional shapes of nanopores were simulated, and the nanopores simulated in the model crystalline material were found to be more stable than the nanopores simulated in the amorphous material. The nanopore shape was also found to depend on the nanopore diameter-to-length ratio. Based on the above, we demonstrate the advantage in using a crystalline material for nanopore formation and show that control of the three-dimensional shape of nanopores formed by electron beam irradiation is possible.
纳米尺度的孔（纳米孔）通常在非晶材料中形成，用于研究分子质量传输的基本原理。在当前的研究中，电子束辐照在透射电子显微镜中用于在晶态材料（Si）中形成纳米孔。对纳米孔的分析表明，它们是由高能入射电子束的原子碰撞形成的，表面扩散部分负责形成沙漏形状，而沙漏形状是某些纳米孔所具有的特征。对纳米孔的有利的三维形状进行了模拟，并且在模型晶态材料中模拟的纳米孔比在非晶态材料中模拟的纳米孔更稳定。还发现纳米孔的形状取决于纳米孔直径与长度的比值。基于以上研究，我们证明了在纳米孔形成中使用晶态材料的优势，并表明可以控制电子束辐照形成的纳米孔的三维形状。
