Atomic resolution elemental mapping using energy-filtered imaging scanning transmission electron microscopy with...

Area of Science:

• Materials Science
• Microscopy
• Spectroscopy

Background:

• Established methods like electron energy-loss spectroscopy (EELS) in scanning transmission electron microscopy (STEM) provide elemental maps but face limitations.
• Preservation of elastic contrast in energy-filtered transmission electron microscopy (EFTEM) can lead to inaccurate elemental distribution visualization.

Purpose of the Study:

• To demonstrate a novel approach for atomic resolution elemental mapping using energy-filtered imaging scanning transmission electron microscopy (EFISTEM).
• To showcase EFISTEM's capability to produce elemental maps with resolution comparable to established techniques.
• To highlight EFISTEM's advantages over EFTEM, particularly in mitigating artifacts.

Main Methods:

• Development and experimental validation of EFISTEM, a technique leveraging chromatic aberration correction.
• Application of EFISTEM to a proof-of-principle study on strontium titanate.
• Utilizing quantum mechanical image simulations to support experimental findings and understand image formation.

Main Results:

• EFISTEM achieves atomic resolution elemental mapping with comparable resolution to EELS-STEM.
• Elemental maps generated by EFISTEM are immune to spatial incoherence, lens aberrations, and probe jitter.
• EFISTEM significantly reduces the preservation of elastic contrast, a common issue in EFTEM, leading to more accurate elemental distribution and stable contrast.

Conclusions:

• EFISTEM represents a significant advancement in atomic resolution elemental mapping.
• The technique offers improved accuracy and stability in elemental mapping compared to existing methods.
• EFISTEM holds promise for detailed nanoscale chemical analysis in materials science.