Quantitative comparison of transmission electron microscopy techniques for the study of localized ordering on a nanoscale
Quantitative comparison of transmission electron microscopy techniques for the study of localized ordering on a nanoscale
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用于研究纳米尺度局部有序的透射电子显微镜技术的定量比较
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
R. Newnham
中科院分区：
文献类型：
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作者：
Xiaoqing Pan;W. Kaplan;M. Rühle;R. Newnham
比较了不同的透射电子显微镜技术对无序基质相中纳米尺度有序区域的探测和尺寸测量。以不同掺杂量La的钙钛矿型Nb镁铅酸盐为模型体系进行了实验研究。选区电子衍射可以揭示有序结构的存在，而暗场对比度显微镜通常用于揭示有序区域的空间分布和大小。然而，对于直径几纳米的小有序区域，由于投影的叠加，测量结果不再准确。高分辨电子显微镜(HRTEM)与图像处理相结合的技术被证明是提供这种局域有序化的定量测量的合适技术。利用实验结果和HRTEM图像模拟，详细讨论了该方法的检测极限。
Different transmission electron microscopy techniques have been compared for the detection and size measurements of ordered regions on a nanometer scale in a disordered matrix phase. As a model system, the perovskite lead magnesium niobate doped with varying amounts of La has been chosen for the present study. While selected area electron diffraction can reveal the existence of ordered structures, dark-field contrast micrographs are usually used to reveal the spatial distribution and the size of ordered regions. However, for small ordered regions, a few nanometers in diameter, the measurements are no longer accurate because of superposition in projection. High-resolution transmission electron microscopy (HRTEM) combined with image processing is shown to be a suitable technique to provide a quantitative measurement of such localized ordering. The detection limit of this method is discussed in detail, using the experimental results and HRTEM image simulations.