arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1209.3558cond-mat.mtrl-scicond-mat.other
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像差校正高分辨透射电子显微术中点扩散的研究

Study of point spread in aberration-corrected high-resolution transmission electron microscopy

Binghui Ge, Yumei Wang, Yuan Yao, Fanghua Li

摘要:

对于定量电子显微镜,高精度的位置信息是必要的,使得除了足够的分辨率和足够强的原子对比度之外,还需要在结构图像中代表原子的峰的小宽度。当点分辨率达到亚埃量级时,峰的大小由仪器的点扩展(PS)和原子的点扩展决定,因此仪器的PS与原子的PS相当。本文利用动态图像模拟方法研究了铯原子负成像(NCSI)和铯原子正成像(PCSI)模式下PS与原子序数、样品厚度和球差系数的关系。通过比较不同厚度和不同球差值下的峰宽,发现NCSI模式优于PCSI模式,因为结构图像中的峰宽较小。

英文摘要:

For quantitative electron microscopy high precision position information is necessary so that besides an adequate resolution and sufficiently strong contrast of atoms, small width of peaks which represent atoms in structural images is needed. Size of peak is determined by point spread (PS) of instruments as well as that of atoms when point resolution reach the subangstrom scale and thus PS of instruments is comparable with that of atoms. In this article, relationship between PS with atomic numbers, sample thickness, and spherical aberration coefficients will be studied in both negative Cs imaging (NCSI) and positive Cs imaging (PCSI) modes by means of dynamical image simulation. Through comparing the peak width with different thickness and different values of spherical aberration, NCSI mode is found to be superior to PCSI considering smaller peak width in the structural image.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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