High-resolution three-dimensional imaging of dislocations
High-resolution three-dimensional imaging of dislocations
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DOI：
10.1126/science.1125783
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发表时间：
2006-07-21
期刊：
影响因子：
56.9
通讯作者：
Midgley, P. A.
中科院分区：
文献类型：
--
作者：
Barnard, J. S.;Sharp, J.;Midgley, P. A.
位错及其相互作用控制着许多材料的特性，从金属的加工硬化到半导体激光二极管的器件病理学。然而，传统的电子显微照片只是三维（3D）结构的二维投影，甚至立体显微镜也无法揭示缺陷结构的真实3D复杂性。在这里，我们描述了一种电子断层扫描方法，该方法可以产生位错网络的 3D 重建，其空间分辨率比以前的工作好三个数量级。我们通过研究 GaN 外延层中的位错来说明该方法的成功，其中位错密度通常为每平方厘米 1010 个。
Dislocations and their interactions govern the properties of many materials, ranging from work hardening in metals to device pathology in semiconductor laser diodes. However, conventional electron micrographs are simply two-dimensional projections of three-dimensional (3D) structures, and even stereo microscopy cannot reveal the true 3D complexity of defect structures. Here, we describe an electron tomographic method that yields 3D reconstructions of dislocation networks with a spatial resolution three orders of magnitude better than previous work. We illustrate the method's success with a study of dislocations in a GaN epilayer, where dislocation densities of 1010 per square centimeter are common.