High-resolution transmission electron microscopy with an electrostatic Zach phase plate
High-resolution transmission electron microscopy with an electrostatic Zach phase plate
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DOI：
10.1088/1367-2630/18/5/053005
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发表时间：
2016-05-06
影响因子：
3.3
通讯作者：
Gerthsen, D.
中科院分区：
文献类型：
--
作者：
Hettler, S.;Dries, M.;Gerthsen, D.
提出了一种利用物理相位板控制高分辨透射电子显微镜（HRTEM）图像中点阵条纹衬度的新方法。PP通常与光学显微镜中的Zernike PP类似，用于增强具有nm尺寸特征的弱相位物体的相位对比度，这经常发生在生命科学应用中。这样的对象，否则需要强大的散焦，这会导致仪器分辨率的退化，并妨碍直观的图像解释。通过对单晶Si和Ge样品的研究，证明了静电Zach PP在HRTEM中的成功应用。Zach PP对成像过程的影响通过分析功率谱中的（111）反射的幅度来评估，功率谱中的（111）反射的幅度在理论预测的一定条件下显示出对诱导相移的余弦型依赖性。
A new method to control lattice-fringe contrast in high-resolution transmission electron microscopy (HRTEM) images by the implementation of a physical phase plate (PP) is proposed. PPs are commonly used in analogy to Zernike PPs in light microscopy to enhance the phase contrast of weak-phase objects with nm-sized features, which often occur in life science applications. Such objects otherwise require strong defocusing, which leads to a degradation of the instrumental resolution and impedes intuitive image interpretation. The successful application of an electrostatic Zach PP in HRTEM is demonstrated by the investigation of single crystalline Si and Ge samples. The influence of the Zach PP on the image formation process is assessed by analyzing the amplitudes of (111) reflections in power spectra which show a cosine-type dependence on the induced phase shift under certain conditions as predicted by theory.