Effects of Dynamical Electron Diffraction on Phase Shift Detected by Electron Holography

Abstract

Recently, the effect of dynamical electron diffraction on the phase shift in electromagnetic field analysis using transmission electron microscopy has become increasingly important. In the present study, we investigated the effect of dynamical electron diffraction on the phase shift in electron holograms recorded from a wedge-shaped specimen of single-crystal Si around a Bragg diffraction condition. The results show that the effective inner potential depends on the direction of the incident electron beam, especially near Bragg conditions. The characteristic phase shift was analyzed using dynamical electron diffraction theory (Bethe method).

Fig. 1 Multi-beam dynamical electron diffraction theory (Bethe method) calculations. The columns (a)–(e) show different diffraction conditions. (i) The complex value ψ₀ exp (−2πi |χ|t) plotted on a complex plane with thickness as a parameter. (ii) Intensity and (iii) phase shift plotted as a function of thickness. The data from 20 nm to 80 nm are plotted by red bold lines.