New technique boosts electron microscope’s clarity

Fig. 1: Gold on amorphous carbon reconstruction results. (a) Exit wave produced by simulating the propagation of an electron plane wave through the multi-slice model produced by a ptychographic reconstruction on experimental 20 keV electron diffraction data obtained from gold particles supported on amorphous carbon, and (b) enlarged region of the reconstructed exit-wave. The colour scale for (a and b) is in the lower right corner of (b), where the colour wheel’s azimuthal angle, ϕ, represents the phase (spanning 0 – 2π) and the radial coordinate represents the amplitude of the wave, spanning an amplitude of 0.43 – 2.35. c Amplitude of the Fourier transform (FT) of the intensity of the reconstructed exit wave. In (c), the intensity is gamma adjusted by 0.9, the upper and lower 1% of pixels are saturated, and the colour scale, which linearly represents the amplitude0.9 is inset at the lower right. Scalebars: (a) – 10 nm, (b) – 5 nm, (c) – 1 Å−¹. @ Nature Communications 16, 8977 (2025). https://doi.org/10.1038/s41467-025-64133-3

A team of researchers at the University of Victoria (UVic) have achieved a major breakthrough in electron microscopy that will allow scientists to visualize atomic-scale structures with unprecedented clarity using lower-cost and lower-energy microscopes than ever before.

Led by Arthur Blackburn, co-director of UVic’s Advanced Microscopy Facility, the team developed a novel imaging technique that allowed them to achieve sub-Ångström resolution (less than one ten-billionth of a meter) using a compact, low-energy scanning electron microscope (SEM)—a feat previously possible only with a large, high-cost transmission electron microscope (TEM).

The research, published in Nature Communications, opens the door to more accessible microscopy for labs around the world. The new technique allows for high-resolution, atomic-scale images without the previously prohibitive cost, space and personnel requirements.

The breakthrough was made possible by applying a technique called ptychography, which uses overlapping patterns of scattered electrons to build a highly detailed picture of a sample. Using this technique, the team was able to reach a resolution of just 0.67 Ångström—less than the size of an atom, and 1/10,000 the width of a human hair—using a low-energy beam on a SEM. Previously, achieving sub-Ångström resolution required a high-energy beam and a TEM.

“This could be transformative for fields like materials science, nanotechnology and structural biology,” says Blackburn. “The advance will most immediately benefit the research and production of 2D materials, which are promising in the development of next-generation electronics. Long term, it could also assist in determining the structure of small proteins, leading to advances in health and disease research.”

Reference Sub-ångström resolution ptychography in a scanning electron microscope at 20 keV

Arthur M. Blackburn, Cristina Cordoba, Matthew R. Fitzpatrick & Robert A. McLeod

https://www.nature.com/articles/s41467-025-64133-3

University of Victoria