Accurate post-mortem alignment for Focused Ion Beam and Scanning Electron Microscopy (FIB-SEM) tomography

Area of Science:

• Materials Science
• Microscopy
• Nanotechnology

Background:

• Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) tomography is crucial for 3D microstructural analysis.
• Sample drifts during FIB-SEM slice-and-view experiments introduce significant inaccuracies in volume reconstruction.
• Current alignment methods like cross-correlation are prone to errors and can be unreliable.

Purpose of the Study:

• To develop and evaluate a novel image alignment procedure for FIB-SEM tomography.
• To address the inaccuracies caused by sample drifts in 3D reconstruction.
• To compare the performance of the new method against existing techniques.

Main Methods:

• A new alignment procedure was developed based on quantifying the topography of the sample surface.
• This novel method was compared with standard cross-correlation alignment.
• An alternative approach using an artificial reference marker fabricated during the FIB process was also evaluated.

Main Results:

• The novel topography-based alignment procedure demonstrated superior accuracy and reliability.
• Cross-correlation methods were shown to be potentially flawed and hazardous for image alignment.
• The performance of all evaluated methods was discussed in terms of their accuracy and liability.

Conclusions:

• Quantifying sample surface topography provides a more accurate and reliable method for aligning FIB-SEM images.
• This new approach mitigates inaccuracies in 3D volume reconstruction and morphological parameter quantification.
• The developed method offers a significant improvement for high-fidelity 3D microstructural analysis using FIB-SEM tomography.