Aberration-corrected transmission electron microscopy with Zernike phase plates

Simon Hettler; Raul Arenal

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arXiv · 2202.00960

Aberration-corrected transmission electron microscopy with Zernike phase plates

Simon Hettler·Raul Arenal

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Abstract

We explore the possibility of applying physical phase plates (PPs) in combination with aberration-corrected transmission electron microscopy. Phase-contrast transfer characteristics are calculated and compared for a thin-film based Zernike PP, a hole-free (HF) or Volta PP and an electrostatic Zach PP, considering their phase-shifting properties in combination with partial spatial coherence. The effect of slightly converging illumination conditions, often used in high-resolution applications, on imaging with PPs is discussed. Experiments with an unheated Zernike PP applied to various nanomaterial specimens and a qualitative analysis clearly demonstrates the general compatibility of PPs and aberration-corrected transmission electron microscopy. Calculations and experiments show the benefits of the approach, among which is a strong phase-contrast enhancement of a large range of spatial frequencies. This allows the simultaneous imaging of atomic-resolution structures and morphological features at the nanometer scale, with maximum phase contrast. The calculations can explain why the HFPP damps contrast transfer at higher spatial frequencies.

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Simon Hettler, Raul Arenal. 2022-02-02. Aberration-corrected transmission electron microscopy with Zernike phase plates. https://arxiv.org/abs/2202.00960

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