Electron holographic material analysis at atomic dimensions
Electron holographic material analysis at atomic dimensions
复制标题
原子维度的电子全息材料分析
DOI：
10.1002/crat.200410318
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发表时间：
2005
影响因子：
1.5
通讯作者：
Hannes Lichte
中科院分区：
文献类型：
--
作者：
M. Lehmann;Hannes Lichte
在[110]取向的GaAs中，由于Ga和As的原子序数相差很小（ZGa = 31, ZAs = 33），因此用常规透射电镜（TEM）很难区分这两种类型的原子柱。定量离轴电子全息可以明确地确定GaAs在[110]取向上的结构极性，其中，除了横向分辨率外，相位信号的灵敏度起着最重要的作用。为了将相位信号仅归因于不同类型的原子，使用相同的楔形GaAs晶体进行了两次全息实验，在第二次实验中，将样品倒置插入支架中，产生相反的GaAs结构极性。（©2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim）
In [110]‐oriented GaAs, both types of atomic columns can hardly be distinguished by conventional transmission electron microscopy (TEM) because of the small difference of atomic numbers for Ga and As with ZGa = 31 and ZAs = 33. Quantitative off‐axis electron holography allows unambiguously determining the structural polarity of GaAs in [110]‐orientation, where, besides lateral resolution, the sensitivity of the phase signal plays the most important role. In order to attribute the phase signal only to the different types of atoms, two holographic experiments were performed using the same wedge‐shaped GaAs‐crystal, where for the second experiment, the sample was inserted into the holder upside down yielding an inverse structural polarity of GaAs. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)