Aberration Correction for Large-Angle Illumination Scanning Transmission Electron Microscopy by Using Iterative...

Area of Science:

• Materials Science
• Physics
• Electron Microscopy

Background:

• Modern aberration correctors in scanning transmission electron microscopy (STEM) enhance spatial resolution and enable atomic-scale analysis at low voltages.
• Aberration correction for large-angle illumination is challenging, limiting advancements in super-resolution, 3D atomic depth, and surface morphology analyses.

Purpose of the Study:

• To demonstrate the feasibility of aberration correction for large-angle illumination in STEM using electron ptychography.
• To overcome current technological limitations in high-angle aberration correction for advanced microscopy applications.

Main Methods:

• Utilized electron ptychography with four-dimensional STEM data acquisition.
• Employed regularized ptychographic iterative engine algorithms to reconstruct 4D datasets.
• Acquired data using a complementary metal-oxide-semiconductor camera at relatively low efficiency.

Main Results:

• Achieved successful aberration correction for large-angle illumination (50-60 mrad).
• Demonstrated super-resolution imaging with a resolution of 0.71 Å.
• Operated under a low accelerating voltage of 60 kV.

Conclusions:

• Electron ptychography offers a viable post-processing strategy to surpass limitations in STEM aberration correction.
• This method enables high-resolution atomic-scale imaging with large-angle illumination at reduced accelerating voltages.