Atomistic mechanical processing and visualization

采用空间分辨率为0.1nm，时间分辨率为1/60 s的时间分辨高分辨率透射电子显微镜对机械加工的原子过程进行原位直接观察。在200千伏电子显微镜下，利用压电驱动技术，纳米尺寸的金和硅尖端接近、接触、结合、变形和断裂。在金、硅/氧化硅/硅隧道结和硅/金簇/硅的量子点中，产生了几个原子柱宽度的接触边界。靠近表面和接触边界的一些层负责键合和分离过程。采用与扫描探针显微镜相似的原子尺度接触式或非接触式表面扫描方法。还证明了一个原子层的机械去除。提出了摩擦试验、压缩试验、拉伸试验和剪切变形试验等新型原子尺度力学试验方法。

Atomic processes of mechanical processing were performed and directly observed in situ by time-resolved high-resolution transmission electron microscopy at spatial resolution of 0.1nm and time resolution of 1/60 s.Nanometer-sized tips of gold and silicon approached, and were contacted, bonded, deformed and fractured inside a 200 kV electron microscope using a piezo-driving. Contact boundaries of a few atomic columns width in gold, silicon/silicon-oxide/silicon tunnel junctions, and quantum dots of silicon/gold-cluster/silicon were produced. A few layers near the surfaces and contact-boundaries were responsible for the bonding and separation processes. Atomic scale contact or non-contact type surface-scanning similar to that in scanning probe microscopy was performed by the same method. The mechanical removal of one atomic layer was also demonstrated. New kinds of atomic scale mechanical tests, such as friction test, compressing, tensile and shear deformation tests were proposed.