Fabrication of a versatile substrate for finding samples on the nanometer scale

Area of Science:

• Materials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Relocating nanometer-scale objects across different analytical systems presents a significant research challenge.
• Existing transmission electron microscope (TEM) grids have limited resolution for precise nanoscale localization.

Purpose of the Study:

• To introduce a novel technique for creating universal substrates for nanoscale analysis.
• To enable accurate relocation of regions of interest (ROI) across diverse imaging modalities.

Main Methods:

• Utilizing focused ion beam (FIB) milling to create precise reference grids on various substrates.
• Demonstrating the technique on both commercial TEM grids and bulk glass samples.
• Employing multiple analytical techniques including optical microscopy, FIB, SEM, TEM, and AFM for validation.

Main Results:

• Achieved sub-micrometer resolution for reference grids, significantly improving upon standard TEM grid spacings.
• Successfully demonstrated the ability to relocate nanoscale features (e.g., 25 nm gold nanoparticles) using the milled grids.
• Validated the technique's applicability across a range of analytical instruments without special sample preparation.

Conclusions:

• The FIB-milled reference grid technique provides a universal solution for nanoscale sample navigation.
• This method enhances the precision and ease of relocating ROIs in advanced microscopy and analysis.
• The technique is versatile, applicable to various substrates and compatible with multiple imaging techniques.