Electron dose dependence of signal-to-noise ratio, atom contrast and resolution in transmission electron microscope images.

نویسندگان

  • Z Lee
  • H Rose
  • O Lehtinen
  • J Biskupek
  • U Kaiser
چکیده

In order to achieve the highest resolution in aberration-corrected (AC) high-resolution transmission electron microscopy (HRTEM) images, high electron doses are required which only a few samples can withstand. In this paper we perform dose-dependent AC-HRTEM image calculations, and study the dependence of the signal-to-noise ratio, atom contrast and resolution on electron dose and sampling. We introduce dose-dependent contrast, which can be used to evaluate the visibility of objects under different dose conditions. Based on our calculations, we determine optimum samplings for high and low electron dose imaging conditions.

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عنوان ژورنال:
  • Ultramicroscopy

دوره 145  شماره 

صفحات  -

تاریخ انتشار 2014